Merge tag 'arc-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

Pull ARC updates from Vineet Gupta:
"Finally a big pile of changes for ARC (atomics/mm). These are from our
internal arc64 tree, preparing mainline for eventual arc64 support.
I'm spreading them out to avoid tsunami of patches in one release.

- MM rework:
- Implement up to 4 paging levels
- Enable STRICT_MM_TYPECHECK
- switch pgtable_t back to 'struct page *'

- Atomics rework / implement relaxed accessors

- Retire legacy MMUv1,v2; ARC750 cores

- A few other build errors, typos"

* tag 'arc-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (33 commits)
ARC: mm: vmalloc sync from kernel to user table to update PMD ...
ARC: mm: support 4 levels of page tables
ARC: mm: support 3 levels of page tables
ARC: mm: switch to asm-generic/pgalloc.h
ARC: mm: switch pgtable_t back to struct page *
ARC: mm: hack to allow 2 level build with 4 level code
ARC: mm: disintegrate pgtable.h into levels and flags
ARC: mm: disintegrate mmu.h (arcv2 bits out)
ARC: mm: move MMU specific bits out of entry code ...
ARC: mm: move MMU specific bits out of ASID allocator
ARC: mm: non-functional code movement/cleanup
ARC: mm: pmd_populate* to use the canonical set_pmd (and drop pmd_set)
ARC: ioremap: use more commonly used PAGE_KERNEL based uncached flag
ARC: mm: Enable STRICT_MM_TYPECHECKS
ARC: mm: Fixes to allow STRICT_MM_TYPECHECKS
ARC: mm: move mmu/cache externs out to setup.h
ARC: mm: remove tlb paranoid code
ARC: mm: use SCRATCH_DATA0 register for caching pgdir in ARCv2 only
ARC: retire MMUv1 and MMUv2 support
ARC: retire ARC750 support
...

arch/arc/Kconfig

···
 	default ARC_CPU_770 if ISA_ARCOMPACT
 	default ARC_CPU_HS if ISA_ARCV2
 
-if ISA_ARCOMPACT
-
-config ARC_CPU_750D
-	bool "ARC750D"
-	select ARC_CANT_LLSC
-	help
-	  Support for ARC750 core
-
 config ARC_CPU_770
 	bool "ARC770"
+	depends on ISA_ARCOMPACT
 	select ARC_HAS_SWAPE
 	help
 	  Support for ARC770 core introduced with Rel 4.10 (Summer 2011)
···
 	           Shared Address Spaces (for sharing TLB entries in MMU)
 	  -Caches: New Prog Model, Region Flush
 	  -Insns: endian swap, load-locked/store-conditional, time-stamp-ctr
-
-endif #ISA_ARCOMPACT
 
 config ARC_CPU_HS
 	bool "ARC-HS"
···
 
 choice
 	prompt "MMU Version"
-	default ARC_MMU_V3 if ARC_CPU_770
-	default ARC_MMU_V2 if ARC_CPU_750D
-	default ARC_MMU_V4 if ARC_CPU_HS
-
-if ISA_ARCOMPACT
-
-config ARC_MMU_V1
-	bool "MMU v1"
-	help
-	  Orig ARC700 MMU
-
-config ARC_MMU_V2
-	bool "MMU v2"
-	help
-	  Fixed the deficiency of v1 - possible thrashing in memcpy scenario
-	  when 2 D-TLB and 1 I-TLB entries index into same 2way set.
+	default ARC_MMU_V3 if ISA_ARCOMPACT
+	default ARC_MMU_V4 if ISA_ARCV2
 
 config ARC_MMU_V3
 	bool "MMU v3"
-	depends on ARC_CPU_770
+	depends on ISA_ARCOMPACT
 	help
 	  Introduced with ARC700 4.10: New Features
 	  Variable Page size (1k-16k), var JTLB size 128 x (2 or 4)
 	  Shared Address Spaces (SASID)
-
-endif
 
 config ARC_MMU_V4
 	bool "MMU v4"
···
 
 config ARC_PAGE_SIZE_16K
 	bool "16KB"
-	depends on ARC_MMU_V3 || ARC_MMU_V4
 
 config ARC_PAGE_SIZE_4K
 	bool "4KB"
···
 	bool "16MB"
 
 endchoice
+
+config PGTABLE_LEVELS
+	int "Number of Page table levels"
+	default 2
 
 config ARC_COMPACT_IRQ_LEVELS
 	depends on ISA_ARCOMPACT
···
 	  but not slower, and it will give very useful debugging information.
 	  If you don't debug the kernel, you can say N, but we may not be able
 	  to solve problems without frame unwind information
-
-config ARC_DBG_TLB_PARANOIA
-	bool "Paranoia Checks in Low Level TLB Handlers"
 
 config ARC_DBG_JUMP_LABEL
 	bool "Paranoid checks in Static Keys (jump labels) code"

arch/arc/include/asm/atomic-llsc.h

···
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef _ASM_ARC_ATOMIC_LLSC_H
+#define _ASM_ARC_ATOMIC_LLSC_H
+
+#define arch_atomic_set(v, i) WRITE_ONCE(((v)->counter), (i))
+
+#define ATOMIC_OP(op, c_op, asm_op)					\
+static inline void arch_atomic_##op(int i, atomic_t *v)			\
+{									\
+	unsigned int val;						\
+									\
+	__asm__ __volatile__(						\
+	"1:	llock   %[val], [%[ctr]]		\n"		\
+	"	" #asm_op " %[val], %[val], %[i]	\n"		\
+	"	scond   %[val], [%[ctr]]		\n"		\
+	"	bnz     1b				\n"		\
+	: [val]	"=&r"	(val) /* Early clobber to prevent reg reuse */	\
+	: [ctr]	"r"	(&v->counter), /* Not "m": llock only supports reg direct addr mode */	\
+	  [i]	"ir"	(i)						\
+	: "cc");							\
+}									\
+
+#define ATOMIC_OP_RETURN(op, c_op, asm_op)				\
+static inline int arch_atomic_##op##_return_relaxed(int i, atomic_t *v)	\
+{									\
+	unsigned int val;						\
+									\
+	__asm__ __volatile__(						\
+	"1:	llock   %[val], [%[ctr]]		\n"		\
+	"	" #asm_op " %[val], %[val], %[i]	\n"		\
+	"	scond   %[val], [%[ctr]]		\n"		\
+	"	bnz     1b				\n"		\
+	: [val]	"=&r"	(val)						\
+	: [ctr]	"r"	(&v->counter),					\
+	  [i]	"ir"	(i)						\
+	: "cc");							\
+									\
+	return val;							\
+}
+
+#define arch_atomic_add_return_relaxed		arch_atomic_add_return_relaxed
+#define arch_atomic_sub_return_relaxed		arch_atomic_sub_return_relaxed
+
+#define ATOMIC_FETCH_OP(op, c_op, asm_op)				\
+static inline int arch_atomic_fetch_##op##_relaxed(int i, atomic_t *v)	\
+{									\
+	unsigned int val, orig;						\
+									\
+	__asm__ __volatile__(						\
+	"1:	llock   %[orig], [%[ctr]]		\n"		\
+	"	" #asm_op " %[val], %[orig], %[i]	\n"		\
+	"	scond   %[val], [%[ctr]]		\n"		\
+	"	bnz     1b				\n"		\
+	: [val]	"=&r"	(val),						\
+	  [orig] "=&r" (orig)						\
+	: [ctr]	"r"	(&v->counter),					\
+	  [i]	"ir"	(i)						\
+	: "cc");							\
+									\
+	return orig;							\
+}
+
+#define arch_atomic_fetch_add_relaxed		arch_atomic_fetch_add_relaxed
+#define arch_atomic_fetch_sub_relaxed		arch_atomic_fetch_sub_relaxed
+
+#define arch_atomic_fetch_and_relaxed		arch_atomic_fetch_and_relaxed
+#define arch_atomic_fetch_andnot_relaxed	arch_atomic_fetch_andnot_relaxed
+#define arch_atomic_fetch_or_relaxed		arch_atomic_fetch_or_relaxed
+#define arch_atomic_fetch_xor_relaxed		arch_atomic_fetch_xor_relaxed
+
+#define ATOMIC_OPS(op, c_op, asm_op)					\
+	ATOMIC_OP(op, c_op, asm_op)					\
+	ATOMIC_OP_RETURN(op, c_op, asm_op)				\
+	ATOMIC_FETCH_OP(op, c_op, asm_op)
+
+ATOMIC_OPS(add, +=, add)
+ATOMIC_OPS(sub, -=, sub)
+
+#undef ATOMIC_OPS
+#define ATOMIC_OPS(op, c_op, asm_op)					\
+	ATOMIC_OP(op, c_op, asm_op)					\
+	ATOMIC_FETCH_OP(op, c_op, asm_op)
+
+ATOMIC_OPS(and, &=, and)
+ATOMIC_OPS(andnot, &= ~, bic)
+ATOMIC_OPS(or, |=, or)
+ATOMIC_OPS(xor, ^=, xor)
+
+#define arch_atomic_andnot		arch_atomic_andnot
+
+#undef ATOMIC_OPS
+#undef ATOMIC_FETCH_OP
+#undef ATOMIC_OP_RETURN
+#undef ATOMIC_OP
+
+#endif

arch/arc/include/asm/atomic-spinlock.h

···
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef _ASM_ARC_ATOMIC_SPLOCK_H
+#define _ASM_ARC_ATOMIC_SPLOCK_H
+
+/*
+ * Non hardware assisted Atomic-R-M-W
+ * Locking would change to irq-disabling only (UP) and spinlocks (SMP)
+ */
+
+static inline void arch_atomic_set(atomic_t *v, int i)
+{
+	/*
+	 * Independent of hardware support, all of the atomic_xxx() APIs need
+	 * to follow the same locking rules to make sure that a "hardware"
+	 * atomic insn (e.g. LD) doesn't clobber an "emulated" atomic insn
+	 * sequence
+	 *
+	 * Thus atomic_set() despite being 1 insn (and seemingly atomic)
+	 * requires the locking.
+	 */
+	unsigned long flags;
+
+	atomic_ops_lock(flags);
+	WRITE_ONCE(v->counter, i);
+	atomic_ops_unlock(flags);
+}
+
+#define arch_atomic_set_release(v, i)	arch_atomic_set((v), (i))
+
+#define ATOMIC_OP(op, c_op, asm_op)					\
+static inline void arch_atomic_##op(int i, atomic_t *v)			\
+{									\
+	unsigned long flags;						\
+									\
+	atomic_ops_lock(flags);						\
+	v->counter c_op i;						\
+	atomic_ops_unlock(flags);					\
+}
+
+#define ATOMIC_OP_RETURN(op, c_op, asm_op)				\
+static inline int arch_atomic_##op##_return(int i, atomic_t *v)		\
+{									\
+	unsigned long flags;						\
+	unsigned int temp;						\
+									\
+	/*								\
+	 * spin lock/unlock provides the needed smp_mb() before/after	\
+	 */								\
+	atomic_ops_lock(flags);						\
+	temp = v->counter;						\
+	temp c_op i;							\
+	v->counter = temp;						\
+	atomic_ops_unlock(flags);					\
+									\
+	return temp;							\
+}
+
+#define ATOMIC_FETCH_OP(op, c_op, asm_op)				\
+static inline int arch_atomic_fetch_##op(int i, atomic_t *v)		\
+{									\
+	unsigned long flags;						\
+	unsigned int orig;						\
+									\
+	/*								\
+	 * spin lock/unlock provides the needed smp_mb() before/after	\
+	 */								\
+	atomic_ops_lock(flags);						\
+	orig = v->counter;						\
+	v->counter c_op i;						\
+	atomic_ops_unlock(flags);					\
+									\
+	return orig;							\
+}
+
+#define ATOMIC_OPS(op, c_op, asm_op)					\
+	ATOMIC_OP(op, c_op, asm_op)					\
+	ATOMIC_OP_RETURN(op, c_op, asm_op)				\
+	ATOMIC_FETCH_OP(op, c_op, asm_op)
+
+ATOMIC_OPS(add, +=, add)
+ATOMIC_OPS(sub, -=, sub)
+
+#undef ATOMIC_OPS
+#define ATOMIC_OPS(op, c_op, asm_op)					\
+	ATOMIC_OP(op, c_op, asm_op)					\
+	ATOMIC_FETCH_OP(op, c_op, asm_op)
+
+ATOMIC_OPS(and, &=, and)
+ATOMIC_OPS(andnot, &= ~, bic)
+ATOMIC_OPS(or, |=, or)
+ATOMIC_OPS(xor, ^=, xor)
+
+#define arch_atomic_andnot		arch_atomic_andnot
+#define arch_atomic_fetch_andnot	arch_atomic_fetch_andnot
+
+#undef ATOMIC_OPS
+#undef ATOMIC_FETCH_OP
+#undef ATOMIC_OP_RETURN
+#undef ATOMIC_OP
+
+#endif

arch/arc/include/asm/atomic.h

···
 #define arch_atomic_read(v)  READ_ONCE((v)->counter)
 
 #ifdef CONFIG_ARC_HAS_LLSC
-
-#define arch_atomic_set(v, i) WRITE_ONCE(((v)->counter), (i))
-
-#define ATOMIC_OP(op, c_op, asm_op)					\
-static inline void arch_atomic_##op(int i, atomic_t *v)			\
-{									\
-	unsigned int val;						\
-									\
-	__asm__ __volatile__(						\
-	"1:	llock   %[val], [%[ctr]]		\n"		\
-	"	" #asm_op " %[val], %[val], %[i]	\n"		\
-	"	scond   %[val], [%[ctr]]		\n"		\
-	"	bnz     1b				\n"		\
-	: [val]	"=&r"	(val) /* Early clobber to prevent reg reuse */	\
-	: [ctr]	"r"	(&v->counter), /* Not "m": llock only supports reg direct addr mode */	\
-	  [i]	"ir"	(i)						\
-	: "cc");							\
-}									\
-
-#define ATOMIC_OP_RETURN(op, c_op, asm_op)				\
-static inline int arch_atomic_##op##_return(int i, atomic_t *v)		\
-{									\
-	unsigned int val;						\
-									\
-	/*								\
-	 * Explicit full memory barrier needed before/after as		\
-	 * LLOCK/SCOND themselves don't provide any such semantics	\
-	 */								\
-	smp_mb();							\
-									\
-	__asm__ __volatile__(						\
-	"1:	llock   %[val], [%[ctr]]		\n"		\
-	"	" #asm_op " %[val], %[val], %[i]	\n"		\
-	"	scond   %[val], [%[ctr]]		\n"		\
-	"	bnz     1b				\n"		\
-	: [val]	"=&r"	(val)						\
-	: [ctr]	"r"	(&v->counter),					\
-	  [i]	"ir"	(i)						\
-	: "cc");							\
-									\
-	smp_mb();							\
-									\
-	return val;							\
-}
-
-#define ATOMIC_FETCH_OP(op, c_op, asm_op)				\
-static inline int arch_atomic_fetch_##op(int i, atomic_t *v)		\
-{									\
-	unsigned int val, orig;						\
-									\
-	/*								\
-	 * Explicit full memory barrier needed before/after as		\
-	 * LLOCK/SCOND themselves don't provide any such semantics	\
-	 */								\
-	smp_mb();							\
-									\
-	__asm__ __volatile__(						\
-	"1:	llock   %[orig], [%[ctr]]		\n"		\
-	"	" #asm_op " %[val], %[orig], %[i]	\n"		\
-	"	scond   %[val], [%[ctr]]		\n"		\
-	"	bnz     1b				\n"		\
-	: [val]	"=&r"	(val),						\
-	  [orig] "=&r" (orig)						\
-	: [ctr]	"r"	(&v->counter),					\
-	  [i]	"ir"	(i)						\
-	: "cc");							\
-									\
-	smp_mb();							\
-									\
-	return orig;							\
-}
-
-#else	/* !CONFIG_ARC_HAS_LLSC */
-
-#ifndef CONFIG_SMP
-
- /* violating atomic_xxx API locking protocol in UP for optimization sake */
-#define arch_atomic_set(v, i) WRITE_ONCE(((v)->counter), (i))
-
+#include <asm/atomic-llsc.h>
 #else
+#include <asm/atomic-spinlock.h>
+#endif
 
-static inline void arch_atomic_set(atomic_t *v, int i)
-{
-	/*
-	 * Independent of hardware support, all of the atomic_xxx() APIs need
-	 * to follow the same locking rules to make sure that a "hardware"
-	 * atomic insn (e.g. LD) doesn't clobber an "emulated" atomic insn
-	 * sequence
-	 *
-	 * Thus atomic_set() despite being 1 insn (and seemingly atomic)
-	 * requires the locking.
-	 */
-	unsigned long flags;
+#define arch_atomic_cmpxchg(v, o, n)					\
+({									\
+	arch_cmpxchg(&((v)->counter), (o), (n));			\
+})
 
-	atomic_ops_lock(flags);
-	WRITE_ONCE(v->counter, i);
-	atomic_ops_unlock(flags);
-}
+#ifdef arch_cmpxchg_relaxed
+#define arch_atomic_cmpxchg_relaxed(v, o, n)				\
+({									\
+	arch_cmpxchg_relaxed(&((v)->counter), (o), (n));		\
+})
+#endif
 
-#define arch_atomic_set_release(v, i)	arch_atomic_set((v), (i))
+#define arch_atomic_xchg(v, n)						\
+({									\
+	arch_xchg(&((v)->counter), (n));				\
+})
 
+#ifdef arch_xchg_relaxed
+#define arch_atomic_xchg_relaxed(v, n)					\
+({									\
+	arch_xchg_relaxed(&((v)->counter), (n));			\
+})
 #endif
 
 /*
- * Non hardware assisted Atomic-R-M-W
- * Locking would change to irq-disabling only (UP) and spinlocks (SMP)
+ * 64-bit atomics
  */
-
-#define ATOMIC_OP(op, c_op, asm_op)					\
-static inline void arch_atomic_##op(int i, atomic_t *v)			\
-{									\
-	unsigned long flags;						\
-									\
-	atomic_ops_lock(flags);						\
-	v->counter c_op i;						\
-	atomic_ops_unlock(flags);					\
-}
-
-#define ATOMIC_OP_RETURN(op, c_op, asm_op)				\
-static inline int arch_atomic_##op##_return(int i, atomic_t *v)		\
-{									\
-	unsigned long flags;						\
-	unsigned long temp;						\
-									\
-	/*								\
-	 * spin lock/unlock provides the needed smp_mb() before/after	\
-	 */								\
-	atomic_ops_lock(flags);						\
-	temp = v->counter;						\
-	temp c_op i;							\
-	v->counter = temp;						\
-	atomic_ops_unlock(flags);					\
-									\
-	return temp;							\
-}
-
-#define ATOMIC_FETCH_OP(op, c_op, asm_op)				\
-static inline int arch_atomic_fetch_##op(int i, atomic_t *v)		\
-{									\
-	unsigned long flags;						\
-	unsigned long orig;						\
-									\
-	/*								\
-	 * spin lock/unlock provides the needed smp_mb() before/after	\
-	 */								\
-	atomic_ops_lock(flags);						\
-	orig = v->counter;						\
-	v->counter c_op i;						\
-	atomic_ops_unlock(flags);					\
-									\
-	return orig;							\
-}
-
-#endif /* !CONFIG_ARC_HAS_LLSC */
-
-#define ATOMIC_OPS(op, c_op, asm_op)					\
-	ATOMIC_OP(op, c_op, asm_op)					\
-	ATOMIC_OP_RETURN(op, c_op, asm_op)				\
-	ATOMIC_FETCH_OP(op, c_op, asm_op)
-
-ATOMIC_OPS(add, +=, add)
-ATOMIC_OPS(sub, -=, sub)
-
-#undef ATOMIC_OPS
-#define ATOMIC_OPS(op, c_op, asm_op)					\
-	ATOMIC_OP(op, c_op, asm_op)					\
-	ATOMIC_FETCH_OP(op, c_op, asm_op)
-
-ATOMIC_OPS(and, &=, and)
-ATOMIC_OPS(andnot, &= ~, bic)
-ATOMIC_OPS(or, |=, or)
-ATOMIC_OPS(xor, ^=, xor)
-
-#define arch_atomic_andnot		arch_atomic_andnot
-#define arch_atomic_fetch_andnot	arch_atomic_fetch_andnot
-
-#undef ATOMIC_OPS
-#undef ATOMIC_FETCH_OP
-#undef ATOMIC_OP_RETURN
-#undef ATOMIC_OP
-
 #ifdef CONFIG_GENERIC_ATOMIC64
-
 #include <asm-generic/atomic64.h>
-
-#else	/* Kconfig ensures this is only enabled with needed h/w assist */
-
-/*
- * ARCv2 supports 64-bit exclusive load (LLOCKD) / store (SCONDD)
- *  - The address HAS to be 64-bit aligned
- *  - There are 2 semantics involved here:
- *    = exclusive implies no interim update between load/store to same addr
- *    = both words are observed/updated together: this is guaranteed even
- *      for regular 64-bit load (LDD) / store (STD). Thus atomic64_set()
- *      is NOT required to use LLOCKD+SCONDD, STD suffices
- */
-
-typedef struct {
-	s64 __aligned(8) counter;
-} atomic64_t;
-
-#define ATOMIC64_INIT(a) { (a) }
-
-static inline s64 arch_atomic64_read(const atomic64_t *v)
-{
-	s64 val;
-
-	__asm__ __volatile__(
-	"	ldd   %0, [%1]	\n"
-	: "=r"(val)
-	: "r"(&v->counter));
-
-	return val;
-}
-
-static inline void arch_atomic64_set(atomic64_t *v, s64 a)
-{
-	/*
-	 * This could have been a simple assignment in "C" but would need
-	 * explicit volatile. Otherwise gcc optimizers could elide the store
-	 * which borked atomic64 self-test
-	 * In the inline asm version, memory clobber needed for exact same
-	 * reason, to tell gcc about the store.
-	 *
-	 * This however is not needed for sibling atomic64_add() etc since both
-	 * load/store are explicitly done in inline asm. As long as API is used
-	 * for each access, gcc has no way to optimize away any load/store
-	 */
-	__asm__ __volatile__(
-	"	std   %0, [%1]	\n"
-	:
-	: "r"(a), "r"(&v->counter)
-	: "memory");
-}
-
-#define ATOMIC64_OP(op, op1, op2)					\
-static inline void arch_atomic64_##op(s64 a, atomic64_t *v)		\
-{									\
-	s64 val;							\
-									\
-	__asm__ __volatile__(						\
-	"1:				\n"				\
-	"	llockd  %0, [%1]	\n"				\
-	"	" #op1 " %L0, %L0, %L2	\n"				\
-	"	" #op2 " %H0, %H0, %H2	\n"				\
-	"	scondd   %0, [%1]	\n"				\
-	"	bnz     1b		\n"				\
-	: "=&r"(val)							\
-	: "r"(&v->counter), "ir"(a)					\
-	: "cc");							\
-}									\
-
-#define ATOMIC64_OP_RETURN(op, op1, op2)		        	\
-static inline s64 arch_atomic64_##op##_return(s64 a, atomic64_t *v)	\
-{									\
-	s64 val;							\
-									\
-	smp_mb();							\
-									\
-	__asm__ __volatile__(						\
-	"1:				\n"				\
-	"	llockd   %0, [%1]	\n"				\
-	"	" #op1 " %L0, %L0, %L2	\n"				\
-	"	" #op2 " %H0, %H0, %H2	\n"				\
-	"	scondd   %0, [%1]	\n"				\
-	"	bnz     1b		\n"				\
-	: [val] "=&r"(val)						\
-	: "r"(&v->counter), "ir"(a)					\
-	: "cc");	/* memory clobber comes from smp_mb() */	\
-									\
-	smp_mb();							\
-									\
-	return val;							\
-}
-
-#define ATOMIC64_FETCH_OP(op, op1, op2)		        		\
-static inline s64 arch_atomic64_fetch_##op(s64 a, atomic64_t *v)	\
-{									\
-	s64 val, orig;							\
-									\
-	smp_mb();							\
-									\
-	__asm__ __volatile__(						\
-	"1:				\n"				\
-	"	llockd   %0, [%2]	\n"				\
-	"	" #op1 " %L1, %L0, %L3	\n"				\
-	"	" #op2 " %H1, %H0, %H3	\n"				\
-	"	scondd   %1, [%2]	\n"				\
-	"	bnz     1b		\n"				\
-	: "=&r"(orig), "=&r"(val)					\
-	: "r"(&v->counter), "ir"(a)					\
-	: "cc");	/* memory clobber comes from smp_mb() */	\
-									\
-	smp_mb();							\
-									\
-	return orig;							\
-}
-
-#define ATOMIC64_OPS(op, op1, op2)					\
-	ATOMIC64_OP(op, op1, op2)					\
-	ATOMIC64_OP_RETURN(op, op1, op2)				\
-	ATOMIC64_FETCH_OP(op, op1, op2)
-
-ATOMIC64_OPS(add, add.f, adc)
-ATOMIC64_OPS(sub, sub.f, sbc)
-ATOMIC64_OPS(and, and, and)
-ATOMIC64_OPS(andnot, bic, bic)
-ATOMIC64_OPS(or, or, or)
-ATOMIC64_OPS(xor, xor, xor)
-
-#define arch_atomic64_andnot		arch_atomic64_andnot
-#define arch_atomic64_fetch_andnot	arch_atomic64_fetch_andnot
-
-#undef ATOMIC64_OPS
-#undef ATOMIC64_FETCH_OP
-#undef ATOMIC64_OP_RETURN
-#undef ATOMIC64_OP
-
-static inline s64
-arch_atomic64_cmpxchg(atomic64_t *ptr, s64 expected, s64 new)
-{
-	s64 prev;
-
-	smp_mb();
-
-	__asm__ __volatile__(
-	"1:	llockd  %0, [%1]	\n"
-	"	brne    %L0, %L2, 2f	\n"
-	"	brne    %H0, %H2, 2f	\n"
-	"	scondd  %3, [%1]	\n"
-	"	bnz     1b		\n"
-	"2:				\n"
-	: "=&r"(prev)
-	: "r"(ptr), "ir"(expected), "r"(new)
-	: "cc");	/* memory clobber comes from smp_mb() */
-
-	smp_mb();
-
-	return prev;
-}
-
-static inline s64 arch_atomic64_xchg(atomic64_t *ptr, s64 new)
-{
-	s64 prev;
-
-	smp_mb();
-
-	__asm__ __volatile__(
-	"1:	llockd  %0, [%1]	\n"
-	"	scondd  %2, [%1]	\n"
-	"	bnz     1b		\n"
-	"2:				\n"
-	: "=&r"(prev)
-	: "r"(ptr), "r"(new)
-	: "cc");	/* memory clobber comes from smp_mb() */
-
-	smp_mb();
-
-	return prev;
-}
-
-/**
- * arch_atomic64_dec_if_positive - decrement by 1 if old value positive
- * @v: pointer of type atomic64_t
- *
- * The function returns the old value of *v minus 1, even if
- * the atomic variable, v, was not decremented.
- */
-
-static inline s64 arch_atomic64_dec_if_positive(atomic64_t *v)
-{
-	s64 val;
-
-	smp_mb();
-
-	__asm__ __volatile__(
-	"1:	llockd  %0, [%1]	\n"
-	"	sub.f   %L0, %L0, 1	# w0 - 1, set C on borrow\n"
-	"	sub.c   %H0, %H0, 1	# if C set, w1 - 1\n"
-	"	brlt    %H0, 0, 2f	\n"
-	"	scondd  %0, [%1]	\n"
-	"	bnz     1b		\n"
-	"2:				\n"
-	: "=&r"(val)
-	: "r"(&v->counter)
-	: "cc");	/* memory clobber comes from smp_mb() */
-
-	smp_mb();
-
-	return val;
-}
-#define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive
-
-/**
- * arch_atomic64_fetch_add_unless - add unless the number is a given value
- * @v: pointer of type atomic64_t
- * @a: the amount to add to v...
- * @u: ...unless v is equal to u.
- *
- * Atomically adds @a to @v, if it was not @u.
- * Returns the old value of @v
- */
-static inline s64 arch_atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u)
-{
-	s64 old, temp;
-
-	smp_mb();
-
-	__asm__ __volatile__(
-	"1:	llockd  %0, [%2]	\n"
-	"	brne	%L0, %L4, 2f	# continue to add since v != u \n"
-	"	breq.d	%H0, %H4, 3f	# return since v == u \n"
-	"2:				\n"
-	"	add.f   %L1, %L0, %L3	\n"
-	"	adc     %H1, %H0, %H3	\n"
-	"	scondd  %1, [%2]	\n"
-	"	bnz     1b		\n"
-	"3:				\n"
-	: "=&r"(old), "=&r" (temp)
-	: "r"(&v->counter), "r"(a), "r"(u)
-	: "cc");	/* memory clobber comes from smp_mb() */
-
-	smp_mb();
-
-	return old;
-}
-#define arch_atomic64_fetch_add_unless arch_atomic64_fetch_add_unless
-
-#endif	/* !CONFIG_GENERIC_ATOMIC64 */
+#else
+#include <asm/atomic64-arcv2.h>
+#endif
 
 #endif	/* !__ASSEMBLY__ */
 

arch/arc/include/asm/atomic64-arcv2.h

···
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+/*
+ * ARCv2 supports 64-bit exclusive load (LLOCKD) / store (SCONDD)
+ *  - The address HAS to be 64-bit aligned
+ */
+
+#ifndef _ASM_ARC_ATOMIC64_ARCV2_H
+#define _ASM_ARC_ATOMIC64_ARCV2_H
+
+typedef struct {
+	s64 __aligned(8) counter;
+} atomic64_t;
+
+#define ATOMIC64_INIT(a) { (a) }
+
+static inline s64 arch_atomic64_read(const atomic64_t *v)
+{
+	s64 val;
+
+	__asm__ __volatile__(
+	"	ldd   %0, [%1]	\n"
+	: "=r"(val)
+	: "r"(&v->counter));
+
+	return val;
+}
+
+static inline void arch_atomic64_set(atomic64_t *v, s64 a)
+{
+	/*
+	 * This could have been a simple assignment in "C" but would need
+	 * explicit volatile. Otherwise gcc optimizers could elide the store
+	 * which borked atomic64 self-test
+	 * In the inline asm version, memory clobber needed for exact same
+	 * reason, to tell gcc about the store.
+	 *
+	 * This however is not needed for sibling atomic64_add() etc since both
+	 * load/store are explicitly done in inline asm. As long as API is used
+	 * for each access, gcc has no way to optimize away any load/store
+	 */
+	__asm__ __volatile__(
+	"	std   %0, [%1]	\n"
+	:
+	: "r"(a), "r"(&v->counter)
+	: "memory");
+}
+
+#define ATOMIC64_OP(op, op1, op2)					\
+static inline void arch_atomic64_##op(s64 a, atomic64_t *v)		\
+{									\
+	s64 val;							\
+									\
+	__asm__ __volatile__(						\
+	"1:				\n"				\
+	"	llockd  %0, [%1]	\n"				\
+	"	" #op1 " %L0, %L0, %L2	\n"				\
+	"	" #op2 " %H0, %H0, %H2	\n"				\
+	"	scondd   %0, [%1]	\n"				\
+	"	bnz     1b		\n"				\
+	: "=&r"(val)							\
+	: "r"(&v->counter), "ir"(a)					\
+	: "cc");							\
+}									\
+
+#define ATOMIC64_OP_RETURN(op, op1, op2)		        	\
+static inline s64 arch_atomic64_##op##_return_relaxed(s64 a, atomic64_t *v)	\
+{									\
+	s64 val;							\
+									\
+	__asm__ __volatile__(						\
+	"1:				\n"				\
+	"	llockd   %0, [%1]	\n"				\
+	"	" #op1 " %L0, %L0, %L2	\n"				\
+	"	" #op2 " %H0, %H0, %H2	\n"				\
+	"	scondd   %0, [%1]	\n"				\
+	"	bnz     1b		\n"				\
+	: [val] "=&r"(val)						\
+	: "r"(&v->counter), "ir"(a)					\
+	: "cc");	/* memory clobber comes from smp_mb() */	\
+									\
+	return val;							\
+}
+
+#define arch_atomic64_add_return_relaxed	arch_atomic64_add_return_relaxed
+#define arch_atomic64_sub_return_relaxed	arch_atomic64_sub_return_relaxed
+
+#define ATOMIC64_FETCH_OP(op, op1, op2)		        		\
+static inline s64 arch_atomic64_fetch_##op##_relaxed(s64 a, atomic64_t *v)	\
+{									\
+	s64 val, orig;							\
+									\
+	__asm__ __volatile__(						\
+	"1:				\n"				\
+	"	llockd   %0, [%2]	\n"				\
+	"	" #op1 " %L1, %L0, %L3	\n"				\
+	"	" #op2 " %H1, %H0, %H3	\n"				\
+	"	scondd   %1, [%2]	\n"				\
+	"	bnz     1b		\n"				\
+	: "=&r"(orig), "=&r"(val)					\
+	: "r"(&v->counter), "ir"(a)					\
+	: "cc");	/* memory clobber comes from smp_mb() */	\
+									\
+	return orig;							\
+}
+
+#define arch_atomic64_fetch_add_relaxed		arch_atomic64_fetch_add_relaxed
+#define arch_atomic64_fetch_sub_relaxed		arch_atomic64_fetch_sub_relaxed
+
+#define arch_atomic64_fetch_and_relaxed		arch_atomic64_fetch_and_relaxed
+#define arch_atomic64_fetch_andnot_relaxed	arch_atomic64_fetch_andnot_relaxed
+#define arch_atomic64_fetch_or_relaxed		arch_atomic64_fetch_or_relaxed
+#define arch_atomic64_fetch_xor_relaxed		arch_atomic64_fetch_xor_relaxed
+
+#define ATOMIC64_OPS(op, op1, op2)					\
+	ATOMIC64_OP(op, op1, op2)					\
+	ATOMIC64_OP_RETURN(op, op1, op2)				\
+	ATOMIC64_FETCH_OP(op, op1, op2)
+
+ATOMIC64_OPS(add, add.f, adc)
+ATOMIC64_OPS(sub, sub.f, sbc)
+
+#undef ATOMIC64_OPS
+#define ATOMIC64_OPS(op, op1, op2)					\
+	ATOMIC64_OP(op, op1, op2)					\
+	ATOMIC64_FETCH_OP(op, op1, op2)
+
+ATOMIC64_OPS(and, and, and)
+ATOMIC64_OPS(andnot, bic, bic)
+ATOMIC64_OPS(or, or, or)
+ATOMIC64_OPS(xor, xor, xor)
+
+#define arch_atomic64_andnot		arch_atomic64_andnot
+
+#undef ATOMIC64_OPS
+#undef ATOMIC64_FETCH_OP
+#undef ATOMIC64_OP_RETURN
+#undef ATOMIC64_OP
+
+static inline s64
+arch_atomic64_cmpxchg(atomic64_t *ptr, s64 expected, s64 new)
+{
+	s64 prev;
+
+	smp_mb();
+
+	__asm__ __volatile__(
+	"1:	llockd  %0, [%1]	\n"
+	"	brne    %L0, %L2, 2f	\n"
+	"	brne    %H0, %H2, 2f	\n"
+	"	scondd  %3, [%1]	\n"
+	"	bnz     1b		\n"
+	"2:				\n"
+	: "=&r"(prev)
+	: "r"(ptr), "ir"(expected), "r"(new)
+	: "cc");	/* memory clobber comes from smp_mb() */
+
+	smp_mb();
+
+	return prev;
+}
+
+static inline s64 arch_atomic64_xchg(atomic64_t *ptr, s64 new)
+{
+	s64 prev;
+
+	smp_mb();
+
+	__asm__ __volatile__(
+	"1:	llockd  %0, [%1]	\n"
+	"	scondd  %2, [%1]	\n"
+	"	bnz     1b		\n"
+	"2:				\n"
+	: "=&r"(prev)
+	: "r"(ptr), "r"(new)
+	: "cc");	/* memory clobber comes from smp_mb() */
+
+	smp_mb();
+
+	return prev;
+}
+
+/**
+ * arch_atomic64_dec_if_positive - decrement by 1 if old value positive
+ * @v: pointer of type atomic64_t
+ *
+ * The function returns the old value of *v minus 1, even if
+ * the atomic variable, v, was not decremented.
+ */
+
+static inline s64 arch_atomic64_dec_if_positive(atomic64_t *v)
+{
+	s64 val;
+
+	smp_mb();
+
+	__asm__ __volatile__(
+	"1:	llockd  %0, [%1]	\n"
+	"	sub.f   %L0, %L0, 1	# w0 - 1, set C on borrow\n"
+	"	sub.c   %H0, %H0, 1	# if C set, w1 - 1\n"
+	"	brlt    %H0, 0, 2f	\n"
+	"	scondd  %0, [%1]	\n"
+	"	bnz     1b		\n"
+	"2:				\n"
+	: "=&r"(val)
+	: "r"(&v->counter)
+	: "cc");	/* memory clobber comes from smp_mb() */
+
+	smp_mb();
+
+	return val;
+}
+#define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive
+
+/**
+ * arch_atomic64_fetch_add_unless - add unless the number is a given value
+ * @v: pointer of type atomic64_t
+ * @a: the amount to add to v...
+ * @u: ...unless v is equal to u.
+ *
+ * Atomically adds @a to @v, if it was not @u.
+ * Returns the old value of @v
+ */
+static inline s64 arch_atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u)
+{
+	s64 old, temp;
+
+	smp_mb();
+
+	__asm__ __volatile__(
+	"1:	llockd  %0, [%2]	\n"
+	"	brne	%L0, %L4, 2f	# continue to add since v != u \n"
+	"	breq.d	%H0, %H4, 3f	# return since v == u \n"
+	"2:				\n"
+	"	add.f   %L1, %L0, %L3	\n"
+	"	adc     %H1, %H0, %H3	\n"
+	"	scondd  %1, [%2]	\n"
+	"	bnz     1b		\n"
+	"3:				\n"
+	: "=&r"(old), "=&r" (temp)
+	: "r"(&v->counter), "r"(a), "r"(u)
+	: "cc");	/* memory clobber comes from smp_mb() */
+
+	smp_mb();
+
+	return old;
+}
+#define arch_atomic64_fetch_add_unless arch_atomic64_fetch_add_unless
+
+#endif

arch/arc/include/asm/bitops.h

···
 
 #include <linux/types.h>
 #include <linux/compiler.h>
-#include <asm/barrier.h>
-#ifndef CONFIG_ARC_HAS_LLSC
-#include <asm/smp.h>
-#endif
-
-#ifdef CONFIG_ARC_HAS_LLSC
-
-/*
- * Hardware assisted Atomic-R-M-W
- */
-
-#define BIT_OP(op, c_op, asm_op)					\
-static inline void op##_bit(unsigned long nr, volatile unsigned long *m)\
-{									\
-	unsigned int temp;						\
-									\
-	m += nr >> 5;							\
-									\
-	nr &= 0x1f;							\
-									\
-	__asm__ __volatile__(						\
-	"1:	llock       %0, [%1]		\n"			\
-	"	" #asm_op " %0, %0, %2	\n"				\
-	"	scond       %0, [%1]		\n"			\
-	"	bnz         1b			\n"			\
-	: "=&r"(temp)	/* Early clobber, to prevent reg reuse */	\
-	: "r"(m),	/* Not "m": llock only supports reg direct addr mode */	\
-	  "ir"(nr)							\
-	: "cc");							\
-}
-
-/*
- * Semantically:
- *    Test the bit
- *    if clear
- *        set it and return 0 (old value)
- *    else
- *        return 1 (old value).
- *
- * Since ARC lacks a equivalent h/w primitive, the bit is set unconditionally
- * and the old value of bit is returned
- */
-#define TEST_N_BIT_OP(op, c_op, asm_op)					\
-static inline int test_and_##op##_bit(unsigned long nr, volatile unsigned long *m)\
-{									\
-	unsigned long old, temp;					\
-									\
-	m += nr >> 5;							\
-									\
-	nr &= 0x1f;							\
-									\
-	/*								\
-	 * Explicit full memory barrier needed before/after as		\
-	 * LLOCK/SCOND themselves don't provide any such smenatic	\
-	 */								\
-	smp_mb();							\
-									\
-	__asm__ __volatile__(						\
-	"1:	llock       %0, [%2]	\n"				\
-	"	" #asm_op " %1, %0, %3	\n"				\
-	"	scond       %1, [%2]	\n"				\
-	"	bnz         1b		\n"				\
-	: "=&r"(old), "=&r"(temp)					\
-	: "r"(m), "ir"(nr)						\
-	: "cc");							\
-									\
-	smp_mb();							\
-									\
-	return (old & (1 << nr)) != 0;					\
-}
-
-#else /* !CONFIG_ARC_HAS_LLSC */
-
-/*
- * Non hardware assisted Atomic-R-M-W
- * Locking would change to irq-disabling only (UP) and spinlocks (SMP)
- *
- * There's "significant" micro-optimization in writing our own variants of
- * bitops (over generic variants)
- *
- * (1) The generic APIs have "signed" @nr while we have it "unsigned"
- *     This avoids extra code to be generated for pointer arithmatic, since
- *     is "not sure" that index is NOT -ve
- * (2) Utilize the fact that ARCompact bit fidding insn (BSET/BCLR/ASL) etc
- *     only consider bottom 5 bits of @nr, so NO need to mask them off.
- *     (GCC Quirk: however for constant @nr we still need to do the masking
- *             at compile time)
- */
-
-#define BIT_OP(op, c_op, asm_op)					\
-static inline void op##_bit(unsigned long nr, volatile unsigned long *m)\
-{									\
-	unsigned long temp, flags;					\
-	m += nr >> 5;							\
-									\
-	/*								\
-	 * spin lock/unlock provide the needed smp_mb() before/after	\
-	 */								\
-	bitops_lock(flags);						\
-									\
-	temp = *m;							\
-	*m = temp c_op (1UL << (nr & 0x1f));					\
-									\
-	bitops_unlock(flags);						\
-}
-
-#define TEST_N_BIT_OP(op, c_op, asm_op)					\
-static inline int test_and_##op##_bit(unsigned long nr, volatile unsigned long *m)\
-{									\
-	unsigned long old, flags;					\
-	m += nr >> 5;							\
-									\
-	bitops_lock(flags);						\
-									\
-	old = *m;							\
-	*m = old c_op (1UL << (nr & 0x1f));				\
-									\
-	bitops_unlock(flags);						\
-									\
-	return (old & (1UL << (nr & 0x1f))) != 0;			\
-}
-
-#endif
-
-/***************************************
- * Non atomic variants
- **************************************/
-
-#define __BIT_OP(op, c_op, asm_op)					\
-static inline void __##op##_bit(unsigned long nr, volatile unsigned long *m)	\
-{									\
-	unsigned long temp;						\
-	m += nr >> 5;							\
-									\
-	temp = *m;							\
-	*m = temp c_op (1UL << (nr & 0x1f));				\
-}
-
-#define __TEST_N_BIT_OP(op, c_op, asm_op)				\
-static inline int __test_and_##op##_bit(unsigned long nr, volatile unsigned long *m)\
-{									\
-	unsigned long old;						\
-	m += nr >> 5;							\
-									\
-	old = *m;							\
-	*m = old c_op (1UL << (nr & 0x1f));				\
-									\
-	return (old & (1UL << (nr & 0x1f))) != 0;			\
-}
-
-#define BIT_OPS(op, c_op, asm_op)					\
-									\
-	/* set_bit(), clear_bit(), change_bit() */			\
-	BIT_OP(op, c_op, asm_op)					\
-									\
-	/* test_and_set_bit(), test_and_clear_bit(), test_and_change_bit() */\
-	TEST_N_BIT_OP(op, c_op, asm_op)					\
-									\
-	/* __set_bit(), __clear_bit(), __change_bit() */		\
-	__BIT_OP(op, c_op, asm_op)					\
-									\
-	/* __test_and_set_bit(), __test_and_clear_bit(), __test_and_change_bit() */\
-	__TEST_N_BIT_OP(op, c_op, asm_op)
-
-BIT_OPS(set, |, bset)
-BIT_OPS(clear, & ~, bclr)
-BIT_OPS(change, ^, bxor)
-
-/*
- * This routine doesn't need to be atomic.
- */
-static inline int
-test_bit(unsigned int nr, const volatile unsigned long *addr)
-{
-	unsigned long mask;
-
-	addr += nr >> 5;
-
-	mask = 1UL << (nr & 0x1f);
-
-	return ((mask & *addr) != 0);
-}
 
 #ifdef CONFIG_ISA_ARCOMPACT
 
···
  * @result: [1-32]
  * fls(1) = 1, fls(0x80000000) = 32, fls(0) = 0
  */
-static inline __attribute__ ((const)) int fls(unsigned long x)
+static inline __attribute__ ((const)) int fls(unsigned int x)
 {
 	int n;
 
···
  * ffs = Find First Set in word (LSB to MSB)
  * @result: [1-32], 0 if all 0's
  */
-static inline __attribute__ ((const)) int ffs(unsigned long x)
+static inline __attribute__ ((const)) int ffs(unsigned int x)
 {
 	int n;
 
···
 #include <asm-generic/bitops/fls64.h>
 #include <asm-generic/bitops/sched.h>
 #include <asm-generic/bitops/lock.h>
+#include <asm-generic/bitops/atomic.h>
+#include <asm-generic/bitops/non-atomic.h>
 
 #include <asm-generic/bitops/find.h>
 #include <asm-generic/bitops/le.h>

arch/arc/include/asm/cache.h

···
 #define ARCH_SLAB_MINALIGN	8
 #endif
 
-extern void arc_cache_init(void);
-extern char *arc_cache_mumbojumbo(int cpu_id, char *buf, int len);
-extern void read_decode_cache_bcr(void);
-
 extern int ioc_enable;
 extern unsigned long perip_base, perip_end;
 

arch/arc/include/asm/cmpxchg.h

···
 #ifndef __ASM_ARC_CMPXCHG_H
 #define __ASM_ARC_CMPXCHG_H
 
+#include <linux/build_bug.h>
 #include <linux/types.h>
 
 #include <asm/barrier.h>
···
 
 #ifdef CONFIG_ARC_HAS_LLSC
 
-static inline unsigned long
-__cmpxchg(volatile void *ptr, unsigned long expected, unsigned long new)
-{
-	unsigned long prev;
-
-	/*
-	 * Explicit full memory barrier needed before/after as
-	 * LLOCK/SCOND themselves don't provide any such semantics
-	 */
-	smp_mb();
-
-	__asm__ __volatile__(
-	"1:	llock   %0, [%1]	\n"
-	"	brne    %0, %2, 2f	\n"
-	"	scond   %3, [%1]	\n"
-	"	bnz     1b		\n"
-	"2:				\n"
-	: "=&r"(prev)	/* Early clobber, to prevent reg reuse */
-	: "r"(ptr),	/* Not "m": llock only supports reg direct addr mode */
-	  "ir"(expected),
-	  "r"(new)	/* can't be "ir". scond can't take LIMM for "b" */
-	: "cc", "memory"); /* so that gcc knows memory is being written here */
-
-	smp_mb();
-
-	return prev;
-}
-
-#else /* !CONFIG_ARC_HAS_LLSC */
-
-static inline unsigned long
-__cmpxchg(volatile void *ptr, unsigned long expected, unsigned long new)
-{
-	unsigned long flags;
-	int prev;
-	volatile unsigned long *p = ptr;
-
-	/*
-	 * spin lock/unlock provide the needed smp_mb() before/after
-	 */
-	atomic_ops_lock(flags);
-	prev = *p;
-	if (prev == expected)
-		*p = new;
-	atomic_ops_unlock(flags);
-	return prev;
-}
-
-#endif
-
-#define arch_cmpxchg(ptr, o, n) ({			\
-	(typeof(*(ptr)))__cmpxchg((ptr),		\
-				  (unsigned long)(o),	\
-				  (unsigned long)(n));	\
+/*
+ * if (*ptr == @old)
+ *      *ptr = @new
+ */
+#define __cmpxchg(ptr, old, new)					\
+({									\
+	__typeof__(*(ptr)) _prev;					\
+									\
+	__asm__ __volatile__(						\
+	"1:	llock  %0, [%1]	\n"					\
+	"	brne   %0, %2, 2f	\n"				\
+	"	scond  %3, [%1]	\n"					\
+	"	bnz     1b		\n"				\
+	"2:				\n"				\
+	: "=&r"(_prev)	/* Early clobber prevent reg reuse */		\
+	: "r"(ptr),	/* Not "m": llock only supports reg */		\
+	  "ir"(old),							\
+	  "r"(new)	/* Not "ir": scond can't take LIMM */		\
+	: "cc",								\
+	  "memory");	/* gcc knows memory is clobbered */		\
+									\
+	_prev;								\
 })
 
-/*
- * atomic_cmpxchg is same as cmpxchg
- *   LLSC: only different in data-type, semantics are exactly same
- *  !LLSC: cmpxchg() has to use an external lock atomic_ops_lock to guarantee
- *         semantics, and this lock also happens to be used by atomic_*()
- */
-#define arch_atomic_cmpxchg(v, o, n) ((int)arch_cmpxchg(&((v)->counter), (o), (n)))
-
-
-/*
- * xchg (reg with memory) based on "Native atomic" EX insn
- */
-static inline unsigned long __xchg(unsigned long val, volatile void *ptr,
-				   int size)
-{
-	extern unsigned long __xchg_bad_pointer(void);
-
-	switch (size) {
-	case 4:
-		smp_mb();
-
-		__asm__ __volatile__(
-		"	ex  %0, [%1]	\n"
-		: "+r"(val)
-		: "r"(ptr)
-		: "memory");
-
-		smp_mb();
-
-		return val;
-	}
-	return __xchg_bad_pointer();
-}
-
-#define _xchg(ptr, with) ((typeof(*(ptr)))__xchg((unsigned long)(with), (ptr), \
-						 sizeof(*(ptr))))
-
-/*
- * xchg() maps directly to ARC EX instruction which guarantees atomicity.
- * However in !LLSC config, it also needs to be use @atomic_ops_lock spinlock
- * due to a subtle reason:
- *  - For !LLSC, cmpxchg() needs to use that lock (see above) and there is lot
- *    of  kernel code which calls xchg()/cmpxchg() on same data (see llist.h)
- *    Hence xchg() needs to follow same locking rules.
- *
- * Technically the lock is also needed for UP (boils down to irq save/restore)
- * but we can cheat a bit since cmpxchg() atomic_ops_lock() would cause irqs to
- * be disabled thus can't possibly be interrupted/preempted/clobbered by xchg()
- * Other way around, xchg is one instruction anyways, so can't be interrupted
- * as such
- */
-
-#if !defined(CONFIG_ARC_HAS_LLSC) && defined(CONFIG_SMP)
-
-#define arch_xchg(ptr, with)		\
-({					\
-	unsigned long flags;		\
-	typeof(*(ptr)) old_val;		\
-					\
-	atomic_ops_lock(flags);		\
-	old_val = _xchg(ptr, with);	\
-	atomic_ops_unlock(flags);	\
-	old_val;			\
+#define arch_cmpxchg_relaxed(ptr, old, new)				\
+({									\
+	__typeof__(ptr) _p_ = (ptr);					\
+	__typeof__(*(ptr)) _o_ = (old);					\
+	__typeof__(*(ptr)) _n_ = (new);					\
+	__typeof__(*(ptr)) _prev_;					\
+									\
+	switch(sizeof((_p_))) {						\
+	case 4:								\
+		_prev_ = __cmpxchg(_p_, _o_, _n_);			\
+		break;							\
+	default:							\
+		BUILD_BUG();						\
+	}								\
+	_prev_;								\
 })
 
 #else
 
-#define arch_xchg(ptr, with)  _xchg(ptr, with)
+#define arch_cmpxchg(ptr, old, new)				        \
+({									\
+	volatile __typeof__(ptr) _p_ = (ptr);				\
+	__typeof__(*(ptr)) _o_ = (old);					\
+	__typeof__(*(ptr)) _n_ = (new);					\
+	__typeof__(*(ptr)) _prev_;					\
+	unsigned long __flags;						\
+									\
+	BUILD_BUG_ON(sizeof(_p_) != 4);					\
+									\
+	/*								\
+	 * spin lock/unlock provide the needed smp_mb() before/after	\
+	 */								\
+	atomic_ops_lock(__flags);					\
+	_prev_ = *_p_;							\
+	if (_prev_ == _o_)						\
+		*_p_ = _n_;						\
+	atomic_ops_unlock(__flags);					\
+	_prev_;								\
+})
 
 #endif
 
 /*
- * "atomic" variant of xchg()
- * REQ: It needs to follow the same serialization rules as other atomic_xxx()
- * Since xchg() doesn't always do that, it would seem that following definition
- * is incorrect. But here's the rationale:
- *   SMP : Even xchg() takes the atomic_ops_lock, so OK.
- *   LLSC: atomic_ops_lock are not relevant at all (even if SMP, since LLSC
- *         is natively "SMP safe", no serialization required).
- *   UP  : other atomics disable IRQ, so no way a difft ctxt atomic_xchg()
- *         could clobber them. atomic_xchg() itself would be 1 insn, so it
- *         can't be clobbered by others. Thus no serialization required when
- *         atomic_xchg is involved.
+ * xchg
  */
-#define arch_atomic_xchg(v, new) (arch_xchg(&((v)->counter), new))
+#ifdef CONFIG_ARC_HAS_LLSC
+
+#define __xchg(ptr, val)						\
+({									\
+	__asm__ __volatile__(						\
+	"	ex  %0, [%1]	\n"	/* set new value */	        \
+	: "+r"(val)							\
+	: "r"(ptr)							\
+	: "memory");							\
+	_val_;		/* get old value */				\
+})
+
+#define arch_xchg_relaxed(ptr, val)					\
+({									\
+	__typeof__(ptr) _p_ = (ptr);					\
+	__typeof__(*(ptr)) _val_ = (val);				\
+									\
+	switch(sizeof(*(_p_))) {					\
+	case 4:								\
+		_val_ = __xchg(_p_, _val_);				\
+		break;							\
+	default:							\
+		BUILD_BUG();						\
+	}								\
+	_val_;								\
+})
+
+#else  /* !CONFIG_ARC_HAS_LLSC */
+
+/*
+ * EX instructions is baseline and present in !LLSC too. But in this
+ * regime it still needs use @atomic_ops_lock spinlock to allow interop
+ * with cmpxchg() which uses spinlock in !LLSC
+ * (llist.h use xchg and cmpxchg on sama data)
+ */
+
+#define arch_xchg(ptr, val)					        \
+({									\
+	__typeof__(ptr) _p_ = (ptr);					\
+	__typeof__(*(ptr)) _val_ = (val);				\
+									\
+	unsigned long __flags;						\
+									\
+	atomic_ops_lock(__flags);					\
+									\
+	__asm__ __volatile__(						\
+	"	ex  %0, [%1]	\n"					\
+	: "+r"(_val_)							\
+	: "r"(_p_)							\
+	: "memory");							\
+									\
+	atomic_ops_unlock(__flags);					\
+	_val_;								\
+})
+
+#endif
 
 #endif

arch/arc/include/asm/entry-compact.h

···
  * to be saved again on kernel mode stack, as part of pt_regs.
  *-------------------------------------------------------------*/
 .macro PROLOG_FREEUP_REG	reg, mem
-#ifndef ARC_USE_SCRATCH_REG
-	sr  \reg, [ARC_REG_SCRATCH_DATA0]
-#else
 	st  \reg, [\mem]
-#endif
 .endm
 
 .macro PROLOG_RESTORE_REG	reg, mem
-#ifndef ARC_USE_SCRATCH_REG
-	lr  \reg, [ARC_REG_SCRATCH_DATA0]
-#else
 	ld  \reg, [\mem]
-#endif
 .endm
 
 /*--------------------------------------------------------------

arch/arc/include/asm/hugepage.h

···
 extern void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr,
 				 pmd_t *pmd);
 
-/* Generic variants assume pgtable_t is struct page *, hence need for these */
-#define __HAVE_ARCH_PGTABLE_DEPOSIT
-extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
-				       pgtable_t pgtable);
-
-#define __HAVE_ARCH_PGTABLE_WITHDRAW
-extern pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
-
 #define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
 extern void flush_pmd_tlb_range(struct vm_area_struct *vma, unsigned long start,
 				unsigned long end);

arch/arc/include/asm/mmu-arcv2.h

···
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012, 2019-20 Synopsys, Inc. (www.synopsys.com)
+ *
+ * MMUv3 (arc700) / MMUv4 (archs) are software page walked and software managed.
+ * This file contains the TLB access registers and commands
+ */
+
+#ifndef _ASM_ARC_MMU_ARCV2_H
+#define _ASM_ARC_MMU_ARCV2_H
+
+/*
+ * TLB Management regs
+ */
+#define ARC_REG_MMU_BCR		0x06f
+
+#ifdef CONFIG_ARC_MMU_V3
+#define ARC_REG_TLBPD0		0x405
+#define ARC_REG_TLBPD1		0x406
+#define ARC_REG_TLBPD1HI	0	/* Dummy: allows common code */
+#define ARC_REG_TLBINDEX	0x407
+#define ARC_REG_TLBCOMMAND	0x408
+#define ARC_REG_PID		0x409
+#define ARC_REG_SCRATCH_DATA0	0x418
+#else
+#define ARC_REG_TLBPD0		0x460
+#define ARC_REG_TLBPD1		0x461
+#define ARC_REG_TLBPD1HI	0x463
+#define ARC_REG_TLBINDEX	0x464
+#define ARC_REG_TLBCOMMAND	0x465
+#define ARC_REG_PID		0x468
+#define ARC_REG_SCRATCH_DATA0	0x46c
+#endif
+
+/* Bits in MMU PID reg */
+#define __TLB_ENABLE		(1 << 31)
+#define __PROG_ENABLE		(1 << 30)
+#define MMU_ENABLE		(__TLB_ENABLE | __PROG_ENABLE)
+
+/* Bits in TLB Index reg */
+#define TLB_LKUP_ERR		0x80000000
+
+#ifdef CONFIG_ARC_MMU_V3
+#define TLB_DUP_ERR		(TLB_LKUP_ERR | 0x00000001)
+#else
+#define TLB_DUP_ERR		(TLB_LKUP_ERR | 0x40000000)
+#endif
+
+/*
+ * TLB Commands
+ */
+#define TLBWrite    		0x1
+#define TLBRead     		0x2
+#define TLBGetIndex 		0x3
+#define TLBProbe    		0x4
+#define TLBWriteNI		0x5  /* write JTLB without inv uTLBs */
+#define TLBIVUTLB		0x6  /* explicitly inv uTLBs */
+
+#ifdef CONFIG_ARC_MMU_V4
+#define TLBInsertEntry		0x7
+#define TLBDeleteEntry		0x8
+#endif
+
+/* Masks for actual TLB "PD"s */
+#define PTE_BITS_IN_PD0		(_PAGE_GLOBAL | _PAGE_PRESENT | _PAGE_HW_SZ)
+#define PTE_BITS_RWX		(_PAGE_EXECUTE | _PAGE_WRITE | _PAGE_READ)
+
+#define PTE_BITS_NON_RWX_IN_PD1	(PAGE_MASK_PHYS | _PAGE_CACHEABLE)
+
+#ifndef __ASSEMBLY__
+
+struct mm_struct;
+extern int pae40_exist_but_not_enab(void);
+
+static inline int is_pae40_enabled(void)
+{
+	return IS_ENABLED(CONFIG_ARC_HAS_PAE40);
+}
+
+static inline void mmu_setup_asid(struct mm_struct *mm, unsigned long asid)
+{
+	write_aux_reg(ARC_REG_PID, asid | MMU_ENABLE);
+}
+
+static inline void mmu_setup_pgd(struct mm_struct *mm, void *pgd)
+{
+	/* PGD cached in MMU reg to avoid 3 mem lookups: task->mm->pgd */
+#ifdef CONFIG_ISA_ARCV2
+	write_aux_reg(ARC_REG_SCRATCH_DATA0, (unsigned int)pgd);
+#endif
+}
+
+#else
+
+.macro ARC_MMU_REENABLE reg
+	lr \reg, [ARC_REG_PID]
+	or \reg, \reg, MMU_ENABLE
+	sr \reg, [ARC_REG_PID]
+.endm
+
+#endif /* !__ASSEMBLY__ */
+
+#endif

arch/arc/include/asm/mmu.h

···
 #define _ASM_ARC_MMU_H
 
 #ifndef __ASSEMBLY__
+
 #include <linux/threads.h>	/* NR_CPUS */
-#endif
-
-#if defined(CONFIG_ARC_MMU_V1)
-#define CONFIG_ARC_MMU_VER 1
-#elif defined(CONFIG_ARC_MMU_V2)
-#define CONFIG_ARC_MMU_VER 2
-#elif defined(CONFIG_ARC_MMU_V3)
-#define CONFIG_ARC_MMU_VER 3
-#elif defined(CONFIG_ARC_MMU_V4)
-#define CONFIG_ARC_MMU_VER 4
-#endif
-
-/* MMU Management regs */
-#define ARC_REG_MMU_BCR		0x06f
-#if (CONFIG_ARC_MMU_VER < 4)
-#define ARC_REG_TLBPD0		0x405
-#define ARC_REG_TLBPD1		0x406
-#define ARC_REG_TLBPD1HI	0	/* Dummy: allows code sharing with ARC700 */
-#define ARC_REG_TLBINDEX	0x407
-#define ARC_REG_TLBCOMMAND	0x408
-#define ARC_REG_PID		0x409
-#define ARC_REG_SCRATCH_DATA0	0x418
-#else
-#define ARC_REG_TLBPD0		0x460
-#define ARC_REG_TLBPD1		0x461
-#define ARC_REG_TLBPD1HI	0x463
-#define ARC_REG_TLBINDEX	0x464
-#define ARC_REG_TLBCOMMAND	0x465
-#define ARC_REG_PID		0x468
-#define ARC_REG_SCRATCH_DATA0	0x46c
-#endif
-
-#if defined(CONFIG_ISA_ARCV2) || !defined(CONFIG_SMP)
-#define	ARC_USE_SCRATCH_REG
-#endif
-
-/* Bits in MMU PID register */
-#define __TLB_ENABLE		(1 << 31)
-#define __PROG_ENABLE		(1 << 30)
-#define MMU_ENABLE		(__TLB_ENABLE | __PROG_ENABLE)
-
-/* Error code if probe fails */
-#define TLB_LKUP_ERR		0x80000000
-
-#if (CONFIG_ARC_MMU_VER < 4)
-#define TLB_DUP_ERR	(TLB_LKUP_ERR | 0x00000001)
-#else
-#define TLB_DUP_ERR	(TLB_LKUP_ERR | 0x40000000)
-#endif
-
-/* TLB Commands */
-#define TLBWrite    0x1
-#define TLBRead     0x2
-#define TLBGetIndex 0x3
-#define TLBProbe    0x4
-
-#if (CONFIG_ARC_MMU_VER >= 2)
-#define TLBWriteNI  0x5		/* write JTLB without inv uTLBs */
-#define TLBIVUTLB   0x6		/* explicitly inv uTLBs */
-#else
-#define TLBWriteNI  TLBWrite	/* Not present in hardware, fallback */
-#endif
-
-#if (CONFIG_ARC_MMU_VER >= 4)
-#define TLBInsertEntry	0x7
-#define TLBDeleteEntry	0x8
-#endif
-
-#ifndef __ASSEMBLY__
 
 typedef struct {
 	unsigned long asid[NR_CPUS];	/* 8 bit MMU PID + Generation cycle */
 } mm_context_t;
 
-#ifdef CONFIG_ARC_DBG_TLB_PARANOIA
-void tlb_paranoid_check(unsigned int mm_asid, unsigned long address);
-#else
-#define tlb_paranoid_check(a, b)
 #endif
 
-void arc_mmu_init(void);
-extern char *arc_mmu_mumbojumbo(int cpu_id, char *buf, int len);
-void read_decode_mmu_bcr(void);
-
-static inline int is_pae40_enabled(void)
-{
-	return IS_ENABLED(CONFIG_ARC_HAS_PAE40);
-}
-
-extern int pae40_exist_but_not_enab(void);
-
-#endif	/* !__ASSEMBLY__ */
+#include <asm/mmu-arcv2.h>
 
 #endif

arch/arc/include/asm/mmu_context.h

···
 #ifndef _ASM_ARC_MMU_CONTEXT_H
 #define _ASM_ARC_MMU_CONTEXT_H
 
-#include <asm/arcregs.h>
-#include <asm/tlb.h>
 #include <linux/sched/mm.h>
 
+#include <asm/tlb.h>
 #include <asm-generic/mm_hooks.h>
 
-/*		ARC700 ASID Management
+/*		ARC ASID Management
  *
- * ARC MMU provides 8-bit ASID (0..255) to TAG TLB entries, allowing entries
- * with same vaddr (different tasks) to co-exit. This provides for
- * "Fast Context Switch" i.e. no TLB flush on ctxt-switch
+ * MMU tags TLBs with an 8-bit ASID, avoiding need to flush the TLB on
+ * context-switch.
  *
- * Linux assigns each task a unique ASID. A simple round-robin allocation
- * of H/w ASID is done using software tracker @asid_cpu.
- * When it reaches max 255, the allocation cycle starts afresh by flushing
- * the entire TLB and wrapping ASID back to zero.
+ * ASID is managed per cpu, so task threads across CPUs can have different
+ * ASID. Global ASID management is needed if hardware supports TLB shootdown
+ * and/or shared TLB across cores, which ARC doesn't.
+ *
+ * Each task is assigned unique ASID, with a simple round-robin allocator
+ * tracked in @asid_cpu. When 8-bit value rolls over,a new cycle is started
+ * over from 0, and TLB is flushed
  *
  * A new allocation cycle, post rollover, could potentially reassign an ASID
  * to a different task. Thus the rule is to refresh the ASID in a new cycle.
···
 	asid_mm(mm, cpu) = asid_cpu(cpu);
 
 set_hw:
-	write_aux_reg(ARC_REG_PID, hw_pid(mm, cpu) | MMU_ENABLE);
+	mmu_setup_asid(mm, hw_pid(mm, cpu));
 
 	local_irq_restore(flags);
 }
···
 	 */
 	cpumask_set_cpu(cpu, mm_cpumask(next));
 
-#ifdef ARC_USE_SCRATCH_REG
-	/* PGD cached in MMU reg to avoid 3 mem lookups: task->mm->pgd */
-	write_aux_reg(ARC_REG_SCRATCH_DATA0, next->pgd);
-#endif
+	mmu_setup_pgd(next, next->pgd);
 
 	get_new_mmu_context(next);
 }

arch/arc/include/asm/page.h

···
 			unsigned long u_vaddr, struct vm_area_struct *vma);
 void clear_user_page(void *to, unsigned long u_vaddr, struct page *page);
 
-#undef STRICT_MM_TYPECHECKS
+typedef struct {
+	unsigned long pgd;
+} pgd_t;
 
-#ifdef STRICT_MM_TYPECHECKS
-/*
- * These are used to make use of C type-checking..
- */
+#define pgd_val(x)	((x).pgd)
+#define __pgd(x)	((pgd_t) { (x) })
+
+#if CONFIG_PGTABLE_LEVELS > 3
+
+typedef struct {
+	unsigned long pud;
+} pud_t;
+
+#define pud_val(x)      	((x).pud)
+#define __pud(x)        	((pud_t) { (x) })
+
+#endif
+
+#if CONFIG_PGTABLE_LEVELS > 2
+
+typedef struct {
+	unsigned long pmd;
+} pmd_t;
+
+#define pmd_val(x)	((x).pmd)
+#define __pmd(x)	((pmd_t) { (x) })
+
+#endif
+
 typedef struct {
 #ifdef CONFIG_ARC_HAS_PAE40
 	unsigned long long pte;
···
 	unsigned long pte;
 #endif
 } pte_t;
-typedef struct {
-	unsigned long pgd;
-} pgd_t;
+
+#define pte_val(x)	((x).pte)
+#define __pte(x)	((pte_t) { (x) })
+
 typedef struct {
 	unsigned long pgprot;
 } pgprot_t;
 
-#define pte_val(x)      ((x).pte)
-#define pgd_val(x)      ((x).pgd)
-#define pgprot_val(x)   ((x).pgprot)
+#define pgprot_val(x)	((x).pgprot)
+#define __pgprot(x)	((pgprot_t) { (x) })
+#define pte_pgprot(x)	__pgprot(pte_val(x))
 
-#define __pte(x)        ((pte_t) { (x) })
-#define __pgd(x)        ((pgd_t) { (x) })
-#define __pgprot(x)     ((pgprot_t) { (x) })
-
-#define pte_pgprot(x) __pgprot(pte_val(x))
-
-#else /* !STRICT_MM_TYPECHECKS */
-
-#ifdef CONFIG_ARC_HAS_PAE40
-typedef unsigned long long pte_t;
-#else
-typedef unsigned long pte_t;
-#endif
-typedef unsigned long pgd_t;
-typedef unsigned long pgprot_t;
-
-#define pte_val(x)	(x)
-#define pgd_val(x)	(x)
-#define pgprot_val(x)	(x)
-#define __pte(x)	(x)
-#define __pgd(x)	(x)
-#define __pgprot(x)	(x)
-#define pte_pgprot(x)	(x)
-
-#endif
-
-typedef pte_t * pgtable_t;
+typedef struct page *pgtable_t;
 
 /*
  * Use virt_to_pfn with caution:
···
  * virt here means link-address/program-address as embedded in object code.
  * And for ARC, link-addr = physical address
  */
-#define __pa(vaddr)  ((unsigned long)(vaddr))
-#define __va(paddr)  ((void *)((unsigned long)(paddr)))
+#define __pa(vaddr)  		((unsigned long)(vaddr))
+#define __va(paddr)  		((void *)((unsigned long)(paddr)))
 
 #define virt_to_page(kaddr)	pfn_to_page(virt_to_pfn(kaddr))
 #define virt_addr_valid(kaddr)  pfn_valid(virt_to_pfn(kaddr))

arch/arc/include/asm/pgalloc.h

···
 
 #include <linux/mm.h>
 #include <linux/log2.h>
+#include <asm-generic/pgalloc.h>
 
 static inline void
 pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte)
 {
-	pmd_set(pmd, pte);
+	/*
+	 * The cast to long below is OK in 32-bit PAE40 regime with long long pte
+	 * Despite "wider" pte, the pte table needs to be in non-PAE low memory
+	 * as all higher levels can only hold long pointers.
+	 *
+	 * The cast itself is needed given simplistic definition of set_pmd()
+	 */
+	set_pmd(pmd, __pmd((unsigned long)pte));
 }
 
-static inline void
-pmd_populate(struct mm_struct *mm, pmd_t *pmd, pgtable_t ptep)
+static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, pgtable_t pte_page)
 {
-	pmd_set(pmd, (pte_t *) ptep);
-}
-
-static inline int __get_order_pgd(void)
-{
-	return get_order(PTRS_PER_PGD * sizeof(pgd_t));
+	set_pmd(pmd, __pmd((unsigned long)page_address(pte_page)));
 }
 
 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 {
-	int num, num2;
-	pgd_t *ret = (pgd_t *) __get_free_pages(GFP_KERNEL, __get_order_pgd());
+	pgd_t *ret = (pgd_t *) __get_free_page(GFP_KERNEL);
 
 	if (ret) {
+		int num, num2;
 		num = USER_PTRS_PER_PGD + USER_KERNEL_GUTTER / PGDIR_SIZE;
 		memzero(ret, num * sizeof(pgd_t));
 
···
 	return ret;
 }
 
-static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
+#if CONFIG_PGTABLE_LEVELS > 3
+
+static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4dp, pud_t *pudp)
 {
-	free_pages((unsigned long)pgd, __get_order_pgd());
+	set_p4d(p4dp, __p4d((unsigned long)pudp));
 }
 
+#define __pud_free_tlb(tlb, pmd, addr)  pud_free((tlb)->mm, pmd)
 
-/*
- * With software-only page-tables, addr-split for traversal is tweakable and
- * that directly governs how big tables would be at each level.
- * Further, the MMU page size is configurable.
- * Thus we need to programatically assert the size constraint
- * All of this is const math, allowing gcc to do constant folding/propagation.
- */
+#endif
 
-static inline int __get_order_pte(void)
+#if CONFIG_PGTABLE_LEVELS > 2
+
+static inline void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmdp)
 {
-	return get_order(PTRS_PER_PTE * sizeof(pte_t));
+	set_pud(pudp, __pud((unsigned long)pmdp));
 }
 
-static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm)
-{
-	pte_t *pte;
+#define __pmd_free_tlb(tlb, pmd, addr)  pmd_free((tlb)->mm, pmd)
 
-	pte = (pte_t *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
-					 __get_order_pte());
-
-	return pte;
-}
-
-static inline pgtable_t
-pte_alloc_one(struct mm_struct *mm)
-{
-	pgtable_t pte_pg;
-	struct page *page;
-
-	pte_pg = (pgtable_t)__get_free_pages(GFP_KERNEL, __get_order_pte());
-	if (!pte_pg)
-		return 0;
-	memzero((void *)pte_pg, PTRS_PER_PTE * sizeof(pte_t));
-	page = virt_to_page(pte_pg);
-	if (!pgtable_pte_page_ctor(page)) {
-		__free_page(page);
-		return 0;
-	}
-
-	return pte_pg;
-}
-
-static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
-{
-	free_pages((unsigned long)pte, __get_order_pte()); /* takes phy addr */
-}
-
-static inline void pte_free(struct mm_struct *mm, pgtable_t ptep)
-{
-	pgtable_pte_page_dtor(virt_to_page(ptep));
-	free_pages((unsigned long)ptep, __get_order_pte());
-}
+#endif
 
 #define __pte_free_tlb(tlb, pte, addr)  pte_free((tlb)->mm, pte)
 

arch/arc/include/asm/pgtable-bits-arcv2.h

···
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+/*
+ * page table flags for software walked/managed MMUv3 (ARC700) and MMUv4 (HS)
+ * There correspond to the corresponding bits in the TLB
+ */
+
+#ifndef _ASM_ARC_PGTABLE_BITS_ARCV2_H
+#define _ASM_ARC_PGTABLE_BITS_ARCV2_H
+
+#ifdef CONFIG_ARC_CACHE_PAGES
+#define _PAGE_CACHEABLE		(1 << 0)  /* Cached (H) */
+#else
+#define _PAGE_CACHEABLE		0
+#endif
+
+#define _PAGE_EXECUTE		(1 << 1)  /* User Execute  (H) */
+#define _PAGE_WRITE		(1 << 2)  /* User Write    (H) */
+#define _PAGE_READ		(1 << 3)  /* User Read     (H) */
+#define _PAGE_ACCESSED		(1 << 4)  /* Accessed      (s) */
+#define _PAGE_DIRTY		(1 << 5)  /* Modified      (s) */
+#define _PAGE_SPECIAL		(1 << 6)
+#define _PAGE_GLOBAL		(1 << 8)  /* ASID agnostic (H) */
+#define _PAGE_PRESENT		(1 << 9)  /* PTE/TLB Valid (H) */
+
+#ifdef CONFIG_ARC_MMU_V4
+#define _PAGE_HW_SZ		(1 << 10)  /* Normal/super (H) */
+#else
+#define _PAGE_HW_SZ		0
+#endif
+
+/* Defaults for every user page */
+#define ___DEF		(_PAGE_PRESENT | _PAGE_CACHEABLE)
+
+/* Set of bits not changed in pte_modify */
+#define _PAGE_CHG_MASK	(PAGE_MASK_PHYS | _PAGE_ACCESSED | _PAGE_DIRTY | \
+							   _PAGE_SPECIAL)
+
+/* More Abbrevaited helpers */
+#define PAGE_U_NONE     __pgprot(___DEF)
+#define PAGE_U_R        __pgprot(___DEF | _PAGE_READ)
+#define PAGE_U_W_R      __pgprot(___DEF | _PAGE_READ | _PAGE_WRITE)
+#define PAGE_U_X_R      __pgprot(___DEF | _PAGE_READ | _PAGE_EXECUTE)
+#define PAGE_U_X_W_R    __pgprot(___DEF \
+				| _PAGE_READ | _PAGE_WRITE | _PAGE_EXECUTE)
+#define PAGE_KERNEL     __pgprot(___DEF | _PAGE_GLOBAL \
+				| _PAGE_READ | _PAGE_WRITE | _PAGE_EXECUTE)
+
+#define PAGE_SHARED	PAGE_U_W_R
+
+#define pgprot_noncached(prot)	(__pgprot(pgprot_val(prot) & ~_PAGE_CACHEABLE))
+
+/*
+ * Mapping of vm_flags (Generic VM) to PTE flags (arch specific)
+ *
+ * Certain cases have 1:1 mapping
+ *  e.g. __P101 means VM_READ, VM_EXEC and !VM_SHARED
+ *       which directly corresponds to  PAGE_U_X_R
+ *
+ * Other rules which cause the divergence from 1:1 mapping
+ *
+ *  1. Although ARC700 can do exclusive execute/write protection (meaning R
+ *     can be tracked independet of X/W unlike some other CPUs), still to
+ *     keep things consistent with other archs:
+ *      -Write implies Read:   W => R
+ *      -Execute implies Read: X => R
+ *
+ *  2. Pvt Writable doesn't have Write Enabled initially: Pvt-W => !W
+ *     This is to enable COW mechanism
+ */
+	/* xwr */
+#define __P000  PAGE_U_NONE
+#define __P001  PAGE_U_R
+#define __P010  PAGE_U_R	/* Pvt-W => !W */
+#define __P011  PAGE_U_R	/* Pvt-W => !W */
+#define __P100  PAGE_U_X_R	/* X => R */
+#define __P101  PAGE_U_X_R
+#define __P110  PAGE_U_X_R	/* Pvt-W => !W and X => R */
+#define __P111  PAGE_U_X_R	/* Pvt-W => !W */
+
+#define __S000  PAGE_U_NONE
+#define __S001  PAGE_U_R
+#define __S010  PAGE_U_W_R	/* W => R */
+#define __S011  PAGE_U_W_R
+#define __S100  PAGE_U_X_R	/* X => R */
+#define __S101  PAGE_U_X_R
+#define __S110  PAGE_U_X_W_R	/* X => R */
+#define __S111  PAGE_U_X_W_R
+
+#ifndef __ASSEMBLY__
+
+#define pte_write(pte)		(pte_val(pte) & _PAGE_WRITE)
+#define pte_dirty(pte)		(pte_val(pte) & _PAGE_DIRTY)
+#define pte_young(pte)		(pte_val(pte) & _PAGE_ACCESSED)
+#define pte_special(pte)	(pte_val(pte) & _PAGE_SPECIAL)
+
+#define PTE_BIT_FUNC(fn, op) \
+	static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
+
+PTE_BIT_FUNC(mknotpresent,     &= ~(_PAGE_PRESENT));
+PTE_BIT_FUNC(wrprotect,	&= ~(_PAGE_WRITE));
+PTE_BIT_FUNC(mkwrite,	|= (_PAGE_WRITE));
+PTE_BIT_FUNC(mkclean,	&= ~(_PAGE_DIRTY));
+PTE_BIT_FUNC(mkdirty,	|= (_PAGE_DIRTY));
+PTE_BIT_FUNC(mkold,	&= ~(_PAGE_ACCESSED));
+PTE_BIT_FUNC(mkyoung,	|= (_PAGE_ACCESSED));
+PTE_BIT_FUNC(mkspecial,	|= (_PAGE_SPECIAL));
+PTE_BIT_FUNC(mkhuge,	|= (_PAGE_HW_SZ));
+
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+	return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
+}
+
+static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
+			      pte_t *ptep, pte_t pteval)
+{
+	set_pte(ptep, pteval);
+}
+
+void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
+		      pte_t *ptep);
+
+/* Encode swap {type,off} tuple into PTE
+ * We reserve 13 bits for 5-bit @type, keeping bits 12-5 zero, ensuring that
+ * PAGE_PRESENT is zero in a PTE holding swap "identifier"
+ */
+#define __swp_entry(type, off)		((swp_entry_t) \
+					{ ((type) & 0x1f) | ((off) << 13) })
+
+/* Decode a PTE containing swap "identifier "into constituents */
+#define __swp_type(pte_lookalike)	(((pte_lookalike).val) & 0x1f)
+#define __swp_offset(pte_lookalike)	((pte_lookalike).val >> 13)
+
+#define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
+#define __swp_entry_to_pte(x)		((pte_t) { (x).val })
+
+#define kern_addr_valid(addr)	(1)
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+#include <asm/hugepage.h>
+#endif
+
+#endif /* __ASSEMBLY__ */
+
+#endif

arch/arc/include/asm/pgtable-levels.h

···
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 Synopsys, Inc. (www.synopsys.com)
+ */
+
+/*
+ * Helpers for implemenintg paging levels
+ */
+
+#ifndef _ASM_ARC_PGTABLE_LEVELS_H
+#define _ASM_ARC_PGTABLE_LEVELS_H
+
+#if CONFIG_PGTABLE_LEVELS == 2
+
+/*
+ * 2 level paging setup for software walked MMUv3 (ARC700) and MMUv4 (HS)
+ *
+ * [31]            32 bit virtual address              [0]
+ * -------------------------------------------------------
+ * |               | <---------- PGDIR_SHIFT ----------> |
+ * |               |                | <-- PAGE_SHIFT --> |
+ * -------------------------------------------------------
+ *       |                  |                |
+ *       |                  |                --> off in page frame
+ *       |                  ---> index into Page Table
+ *       ----> index into Page Directory
+ *
+ * Given software walk, the vaddr split is arbitrary set to 11:8:13
+ * However enabling of super page in a 2 level regime pegs PGDIR_SHIFT to
+ * super page size.
+ */
+
+#if defined(CONFIG_ARC_HUGEPAGE_16M)
+#define PGDIR_SHIFT		24
+#elif defined(CONFIG_ARC_HUGEPAGE_2M)
+#define PGDIR_SHIFT		21
+#else
+/*
+ * No Super page case
+ * Default value provides 11:8:13 (8K), 10:10:12 (4K)
+ * Limits imposed by pgtable_t only PAGE_SIZE long
+ * (so 4K page can only have 1K entries: or 10 bits)
+ */
+#ifdef CONFIG_ARC_PAGE_SIZE_4K
+#define PGDIR_SHIFT		22
+#else
+#define PGDIR_SHIFT		21
+#endif
+
+#endif
+
+#else /* CONFIG_PGTABLE_LEVELS != 2 */
+
+/*
+ * A default 3 level paging testing setup in software walked MMU
+ *   MMUv4 (8K page): <4> : <7> : <8> : <13>
+ * A default 4 level paging testing setup in software walked MMU
+ *   MMUv4 (8K page): <4> : <3> : <4> : <8> : <13>
+ */
+#define PGDIR_SHIFT		28
+#if CONFIG_PGTABLE_LEVELS > 3
+#define PUD_SHIFT		25
+#endif
+#if CONFIG_PGTABLE_LEVELS > 2
+#define PMD_SHIFT		21
+#endif
+
+#endif /* CONFIG_PGTABLE_LEVELS */
+
+#define PGDIR_SIZE		BIT(PGDIR_SHIFT)
+#define PGDIR_MASK		(~(PGDIR_SIZE - 1))
+#define PTRS_PER_PGD		BIT(32 - PGDIR_SHIFT)
+
+#if CONFIG_PGTABLE_LEVELS > 3
+#define PUD_SIZE		BIT(PUD_SHIFT)
+#define PUD_MASK		(~(PUD_SIZE - 1))
+#define PTRS_PER_PUD		BIT(PGDIR_SHIFT - PUD_SHIFT)
+#endif
+
+#if CONFIG_PGTABLE_LEVELS > 2
+#define PMD_SIZE		BIT(PMD_SHIFT)
+#define PMD_MASK		(~(PMD_SIZE - 1))
+#define PTRS_PER_PMD		BIT(PUD_SHIFT - PMD_SHIFT)
+#endif
+
+#define PTRS_PER_PTE		BIT(PMD_SHIFT - PAGE_SHIFT)
+
+#ifndef __ASSEMBLY__
+
+#if CONFIG_PGTABLE_LEVELS > 3
+#include <asm-generic/pgtable-nop4d.h>
+#elif CONFIG_PGTABLE_LEVELS > 2
+#include <asm-generic/pgtable-nopud.h>
+#else
+#include <asm-generic/pgtable-nopmd.h>
+#endif
+
+/*
+ * 1st level paging: pgd
+ */
+#define pgd_index(addr)		((addr) >> PGDIR_SHIFT)
+#define pgd_offset(mm, addr)	(((mm)->pgd) + pgd_index(addr))
+#define pgd_offset_k(addr)	pgd_offset(&init_mm, addr)
+#define pgd_ERROR(e) \
+	pr_crit("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
+
+#if CONFIG_PGTABLE_LEVELS > 3
+
+/* In 4 level paging, p4d_* macros work on pgd */
+#define p4d_none(x)		(!p4d_val(x))
+#define p4d_bad(x)		((p4d_val(x) & ~PAGE_MASK))
+#define p4d_present(x)		(p4d_val(x))
+#define p4d_clear(xp)		do { p4d_val(*(xp)) = 0; } while (0)
+#define p4d_pgtable(p4d)	((pud_t *)(p4d_val(p4d) & PAGE_MASK))
+#define p4d_page(p4d)		virt_to_page(p4d_pgtable(p4d))
+#define set_p4d(p4dp, p4d)	(*(p4dp) = p4d)
+
+/*
+ * 2nd level paging: pud
+ */
+#define pud_ERROR(e) \
+	pr_crit("%s:%d: bad pud %08lx.\n", __FILE__, __LINE__, pud_val(e))
+
+#endif
+
+#if CONFIG_PGTABLE_LEVELS > 2
+
+/*
+ * In 3 level paging, pud_* macros work on pgd
+ * In 4 level paging, pud_* macros work on pud
+ */
+#define pud_none(x)		(!pud_val(x))
+#define pud_bad(x)		((pud_val(x) & ~PAGE_MASK))
+#define pud_present(x)		(pud_val(x))
+#define pud_clear(xp)		do { pud_val(*(xp)) = 0; } while (0)
+#define pud_pgtable(pud)	((pmd_t *)(pud_val(pud) & PAGE_MASK))
+#define pud_page(pud)		virt_to_page(pud_pgtable(pud))
+#define set_pud(pudp, pud)	(*(pudp) = pud)
+
+/*
+ * 3rd level paging: pmd
+ */
+#define pmd_ERROR(e) \
+	pr_crit("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pmd_val(e))
+
+#define pmd_pfn(pmd)		((pmd_val(pmd) & PMD_MASK) >> PAGE_SHIFT)
+#define pfn_pmd(pfn,prot)	__pmd(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
+#define mk_pmd(page,prot)	pfn_pmd(page_to_pfn(page),prot)
+
+#endif
+
+/*
+ * Due to the strange way generic pgtable level folding works, the pmd_* macros
+ *  - are valid even for 2 levels (which supposedly only has pgd - pte)
+ *  - behave differently for 2 vs. 3
+ * In 2  level paging        (pgd -> pte), pmd_* macros work on pgd
+ * In 3+ level paging (pgd -> pmd -> pte), pmd_* macros work on pmd
+ */
+#define pmd_none(x)		(!pmd_val(x))
+#define pmd_bad(x)		((pmd_val(x) & ~PAGE_MASK))
+#define pmd_present(x)		(pmd_val(x))
+#define pmd_clear(xp)		do { pmd_val(*(xp)) = 0; } while (0)
+#define pmd_page_vaddr(pmd)	(pmd_val(pmd) & PAGE_MASK)
+#define pmd_page(pmd)		virt_to_page(pmd_page_vaddr(pmd))
+#define set_pmd(pmdp, pmd)	(*(pmdp) = pmd)
+#define pmd_pgtable(pmd)	((pgtable_t) pmd_page_vaddr(pmd))
+
+/*
+ * 4th level paging: pte
+ */
+#define pte_ERROR(e) \
+	pr_crit("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
+
+#define pte_none(x)		(!pte_val(x))
+#define pte_present(x)		(pte_val(x) & _PAGE_PRESENT)
+#define pte_clear(mm,addr,ptep)	set_pte_at(mm, addr, ptep, __pte(0))
+#define pte_page(pte)		pfn_to_page(pte_pfn(pte))
+#define set_pte(ptep, pte)	((*(ptep)) = (pte))
+#define pte_pfn(pte)		(pte_val(pte) >> PAGE_SHIFT)
+#define pfn_pte(pfn, prot)	__pte(__pfn_to_phys(pfn) | pgprot_val(prot))
+#define mk_pte(page, prot)	pfn_pte(page_to_pfn(page), prot)
+
+#ifdef CONFIG_ISA_ARCV2
+#define pmd_leaf(x)		(pmd_val(x) & _PAGE_HW_SZ)
+#endif
+
+#endif	/* !__ASSEMBLY__ */
+
+#endif

arch/arc/include/asm/pgtable.h

···
 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
- *
- * vineetg: May 2011
- *  -Folded PAGE_PRESENT (used by VM) and PAGE_VALID (used by MMU) into 1.
- *     They are semantically the same although in different contexts
- *     VALID marks a TLB entry exists and it will only happen if PRESENT
- *  - Utilise some unused free bits to confine PTE flags to 12 bits
- *     This is a must for 4k pg-sz
- *
- * vineetg: Mar 2011 - changes to accommodate MMU TLB Page Descriptor mods
- *  -TLB Locking never really existed, except for initial specs
- *  -SILENT_xxx not needed for our port
- *  -Per my request, MMU V3 changes the layout of some of the bits
- *     to avoid a few shifts in TLB Miss handlers.
- *
- * vineetg: April 2010
- *  -PGD entry no longer contains any flags. If empty it is 0, otherwise has
- *   Pg-Tbl ptr. Thus pmd_present(), pmd_valid(), pmd_set( ) become simpler
- *
- * vineetg: April 2010
- *  -Switched form 8:11:13 split for page table lookup to 11:8:13
- *  -this speeds up page table allocation itself as we now have to memset 1K
- *    instead of 8k per page table.
- * -TODO: Right now page table alloc is 8K and rest 7K is unused
- *    need to optimise it
- *
- * Amit Bhor, Sameer Dhavale: Codito Technologies 2004
  */
 
 #ifndef _ASM_ARC_PGTABLE_H
 #define _ASM_ARC_PGTABLE_H
 
 #include <linux/bits.h>
-#include <asm-generic/pgtable-nopmd.h>
+
+#include <asm/pgtable-levels.h>
+#include <asm/pgtable-bits-arcv2.h>
 #include <asm/page.h>
-#include <asm/mmu.h>	/* to propagate CONFIG_ARC_MMU_VER <n> */
-
-/**************************************************************************
- * Page Table Flags
- *
- * ARC700 MMU only deals with softare managed TLB entries.
- * Page Tables are purely for Linux VM's consumption and the bits below are
- * suited to that (uniqueness). Hence some are not implemented in the TLB and
- * some have different value in TLB.
- * e.g. MMU v2: K_READ bit is 8 and so is GLOBAL (possible because they live in
- *      seperate PD0 and PD1, which combined forms a translation entry)
- *      while for PTE perspective, they are 8 and 9 respectively
- * with MMU v3: Most bits (except SHARED) represent the exact hardware pos
- *      (saves some bit shift ops in TLB Miss hdlrs)
- */
-
-#if (CONFIG_ARC_MMU_VER <= 2)
-
-#define _PAGE_ACCESSED      (1<<1)	/* Page is accessed (S) */
-#define _PAGE_CACHEABLE     (1<<2)	/* Page is cached (H) */
-#define _PAGE_EXECUTE       (1<<3)	/* Page has user execute perm (H) */
-#define _PAGE_WRITE         (1<<4)	/* Page has user write perm (H) */
-#define _PAGE_READ          (1<<5)	/* Page has user read perm (H) */
-#define _PAGE_DIRTY         (1<<6)	/* Page modified (dirty) (S) */
-#define _PAGE_SPECIAL       (1<<7)
-#define _PAGE_GLOBAL        (1<<8)	/* Page is global (H) */
-#define _PAGE_PRESENT       (1<<10)	/* TLB entry is valid (H) */
-
-#else	/* MMU v3 onwards */
-
-#define _PAGE_CACHEABLE     (1<<0)	/* Page is cached (H) */
-#define _PAGE_EXECUTE       (1<<1)	/* Page has user execute perm (H) */
-#define _PAGE_WRITE         (1<<2)	/* Page has user write perm (H) */
-#define _PAGE_READ          (1<<3)	/* Page has user read perm (H) */
-#define _PAGE_ACCESSED      (1<<4)	/* Page is accessed (S) */
-#define _PAGE_DIRTY         (1<<5)	/* Page modified (dirty) (S) */
-#define _PAGE_SPECIAL       (1<<6)
-
-#if (CONFIG_ARC_MMU_VER >= 4)
-#define _PAGE_WTHRU         (1<<7)	/* Page cache mode write-thru (H) */
-#endif
-
-#define _PAGE_GLOBAL        (1<<8)	/* Page is global (H) */
-#define _PAGE_PRESENT       (1<<9)	/* TLB entry is valid (H) */
-
-#if (CONFIG_ARC_MMU_VER >= 4)
-#define _PAGE_HW_SZ         (1<<10)	/* Page Size indicator (H): 0 normal, 1 super */
-#endif
-
-#define _PAGE_SHARED_CODE   (1<<11)	/* Shared Code page with cmn vaddr
-					   usable for shared TLB entries (H) */
-
-#define _PAGE_UNUSED_BIT    (1<<12)
-#endif
-
-/* vmalloc permissions */
-#define _K_PAGE_PERMS  (_PAGE_EXECUTE | _PAGE_WRITE | _PAGE_READ | \
-			_PAGE_GLOBAL | _PAGE_PRESENT)
-
-#ifndef CONFIG_ARC_CACHE_PAGES
-#undef _PAGE_CACHEABLE
-#define _PAGE_CACHEABLE 0
-#endif
-
-#ifndef _PAGE_HW_SZ
-#define _PAGE_HW_SZ	0
-#endif
-
-/* Defaults for every user page */
-#define ___DEF (_PAGE_PRESENT | _PAGE_CACHEABLE)
-
-/* Set of bits not changed in pte_modify */
-#define _PAGE_CHG_MASK	(PAGE_MASK_PHYS | _PAGE_ACCESSED | _PAGE_DIRTY | \
-							   _PAGE_SPECIAL)
-/* More Abbrevaited helpers */
-#define PAGE_U_NONE     __pgprot(___DEF)
-#define PAGE_U_R        __pgprot(___DEF | _PAGE_READ)
-#define PAGE_U_W_R      __pgprot(___DEF | _PAGE_READ | _PAGE_WRITE)
-#define PAGE_U_X_R      __pgprot(___DEF | _PAGE_READ | _PAGE_EXECUTE)
-#define PAGE_U_X_W_R    __pgprot(___DEF | _PAGE_READ | _PAGE_WRITE | \
-						       _PAGE_EXECUTE)
-
-#define PAGE_SHARED	PAGE_U_W_R
-
-/* While kernel runs out of unstranslated space, vmalloc/modules use a chunk of
- * user vaddr space - visible in all addr spaces, but kernel mode only
- * Thus Global, all-kernel-access, no-user-access, cached
- */
-#define PAGE_KERNEL          __pgprot(_K_PAGE_PERMS | _PAGE_CACHEABLE)
-
-/* ioremap */
-#define PAGE_KERNEL_NO_CACHE __pgprot(_K_PAGE_PERMS)
-
-/* Masks for actual TLB "PD"s */
-#define PTE_BITS_IN_PD0		(_PAGE_GLOBAL | _PAGE_PRESENT | _PAGE_HW_SZ)
-#define PTE_BITS_RWX		(_PAGE_EXECUTE | _PAGE_WRITE | _PAGE_READ)
-
-#define PTE_BITS_NON_RWX_IN_PD1	(PAGE_MASK_PHYS | _PAGE_CACHEABLE)
-
-/**************************************************************************
- * Mapping of vm_flags (Generic VM) to PTE flags (arch specific)
- *
- * Certain cases have 1:1 mapping
- *  e.g. __P101 means VM_READ, VM_EXEC and !VM_SHARED
- *       which directly corresponds to  PAGE_U_X_R
- *
- * Other rules which cause the divergence from 1:1 mapping
- *
- *  1. Although ARC700 can do exclusive execute/write protection (meaning R
- *     can be tracked independet of X/W unlike some other CPUs), still to
- *     keep things consistent with other archs:
- *      -Write implies Read:   W => R
- *      -Execute implies Read: X => R
- *
- *  2. Pvt Writable doesn't have Write Enabled initially: Pvt-W => !W
- *     This is to enable COW mechanism
- */
-	/* xwr */
-#define __P000  PAGE_U_NONE
-#define __P001  PAGE_U_R
-#define __P010  PAGE_U_R	/* Pvt-W => !W */
-#define __P011  PAGE_U_R	/* Pvt-W => !W */
-#define __P100  PAGE_U_X_R	/* X => R */
-#define __P101  PAGE_U_X_R
-#define __P110  PAGE_U_X_R	/* Pvt-W => !W and X => R */
-#define __P111  PAGE_U_X_R	/* Pvt-W => !W */
-
-#define __S000  PAGE_U_NONE
-#define __S001  PAGE_U_R
-#define __S010  PAGE_U_W_R	/* W => R */
-#define __S011  PAGE_U_W_R
-#define __S100  PAGE_U_X_R	/* X => R */
-#define __S101  PAGE_U_X_R
-#define __S110  PAGE_U_X_W_R	/* X => R */
-#define __S111  PAGE_U_X_W_R
-
-/****************************************************************
- * 2 tier (PGD:PTE) software page walker
- *
- * [31]		    32 bit virtual address              [0]
- * -------------------------------------------------------
- * |               | <------------ PGDIR_SHIFT ----------> |
- * |		   |					 |
- * | BITS_FOR_PGD  |  BITS_FOR_PTE  | <-- PAGE_SHIFT --> |
- * -------------------------------------------------------
- *       |                  |                |
- *       |                  |                --> off in page frame
- *       |                  ---> index into Page Table
- *       ----> index into Page Directory
- *
- * In a single page size configuration, only PAGE_SHIFT is fixed
- * So both PGD and PTE sizing can be tweaked
- *  e.g. 8K page (PAGE_SHIFT 13) can have
- *  - PGDIR_SHIFT 21  -> 11:8:13 address split
- *  - PGDIR_SHIFT 24  -> 8:11:13 address split
- *
- * If Super Page is configured, PGDIR_SHIFT becomes fixed too,
- * so the sizing flexibility is gone.
- */
-
-#if defined(CONFIG_ARC_HUGEPAGE_16M)
-#define PGDIR_SHIFT	24
-#elif defined(CONFIG_ARC_HUGEPAGE_2M)
-#define PGDIR_SHIFT	21
-#else
-/*
- * Only Normal page support so "hackable" (see comment above)
- * Default value provides 11:8:13 (8K), 11:9:12 (4K)
- */
-#define PGDIR_SHIFT	21
-#endif
-
-#define BITS_FOR_PTE	(PGDIR_SHIFT - PAGE_SHIFT)
-#define BITS_FOR_PGD	(32 - PGDIR_SHIFT)
-
-#define PGDIR_SIZE	BIT(PGDIR_SHIFT)	/* vaddr span, not PDG sz */
-#define PGDIR_MASK	(~(PGDIR_SIZE-1))
-
-#define	PTRS_PER_PTE	BIT(BITS_FOR_PTE)
-#define	PTRS_PER_PGD	BIT(BITS_FOR_PGD)
+#include <asm/mmu.h>
 
 /*
  * Number of entries a user land program use.
···
  */
 #define	USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
 
-
-/****************************************************************
- * Bucket load of VM Helpers
- */
-
 #ifndef __ASSEMBLY__
 
-#define pte_ERROR(e) \
-	pr_crit("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
-#define pgd_ERROR(e) \
-	pr_crit("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
-
-/* the zero page used for uninitialized and anonymous pages */
 extern char empty_zero_page[PAGE_SIZE];
 #define ZERO_PAGE(vaddr)	(virt_to_page(empty_zero_page))
 
-#define set_pte(pteptr, pteval)	((*(pteptr)) = (pteval))
-#define set_pmd(pmdptr, pmdval)	(*(pmdptr) = pmdval)
-
-/* find the page descriptor of the Page Tbl ref by PMD entry */
-#define pmd_page(pmd)		virt_to_page(pmd_val(pmd) & PAGE_MASK)
-
-/* find the logical addr (phy for ARC) of the Page Tbl ref by PMD entry */
-#define pmd_page_vaddr(pmd)	(pmd_val(pmd) & PAGE_MASK)
-
-/* In a 2 level sys, setup the PGD entry with PTE value */
-static inline void pmd_set(pmd_t *pmdp, pte_t *ptep)
-{
-	pmd_val(*pmdp) = (unsigned long)ptep;
-}
-
-#define pte_none(x)			(!pte_val(x))
-#define pte_present(x)			(pte_val(x) & _PAGE_PRESENT)
-#define pte_clear(mm, addr, ptep)	set_pte_at(mm, addr, ptep, __pte(0))
-
-#define pmd_none(x)			(!pmd_val(x))
-#define	pmd_bad(x)			((pmd_val(x) & ~PAGE_MASK))
-#define pmd_present(x)			(pmd_val(x))
-#define pmd_leaf(x)			(pmd_val(x) & _PAGE_HW_SZ)
-#define pmd_clear(xp)			do { pmd_val(*(xp)) = 0; } while (0)
-
-#define pte_page(pte)		pfn_to_page(pte_pfn(pte))
-#define mk_pte(page, prot)	pfn_pte(page_to_pfn(page), prot)
-#define pfn_pte(pfn, prot)	__pte(__pfn_to_phys(pfn) | pgprot_val(prot))
-
-/* Don't use virt_to_pfn for macros below: could cause truncations for PAE40*/
-#define pte_pfn(pte)		(pte_val(pte) >> PAGE_SHIFT)
-
-/* Zoo of pte_xxx function */
-#define pte_read(pte)		(pte_val(pte) & _PAGE_READ)
-#define pte_write(pte)		(pte_val(pte) & _PAGE_WRITE)
-#define pte_dirty(pte)		(pte_val(pte) & _PAGE_DIRTY)
-#define pte_young(pte)		(pte_val(pte) & _PAGE_ACCESSED)
-#define pte_special(pte)	(pte_val(pte) & _PAGE_SPECIAL)
-
-#define PTE_BIT_FUNC(fn, op) \
-	static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
-
-PTE_BIT_FUNC(mknotpresent,	&= ~(_PAGE_PRESENT));
-PTE_BIT_FUNC(wrprotect,	&= ~(_PAGE_WRITE));
-PTE_BIT_FUNC(mkwrite,	|= (_PAGE_WRITE));
-PTE_BIT_FUNC(mkclean,	&= ~(_PAGE_DIRTY));
-PTE_BIT_FUNC(mkdirty,	|= (_PAGE_DIRTY));
-PTE_BIT_FUNC(mkold,	&= ~(_PAGE_ACCESSED));
-PTE_BIT_FUNC(mkyoung,	|= (_PAGE_ACCESSED));
-PTE_BIT_FUNC(exprotect,	&= ~(_PAGE_EXECUTE));
-PTE_BIT_FUNC(mkexec,	|= (_PAGE_EXECUTE));
-PTE_BIT_FUNC(mkspecial,	|= (_PAGE_SPECIAL));
-PTE_BIT_FUNC(mkhuge,	|= (_PAGE_HW_SZ));
-
-static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
-{
-	return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
-}
+extern pgd_t swapper_pg_dir[] __aligned(PAGE_SIZE);
 
 /* Macro to mark a page protection as uncacheable */
 #define pgprot_noncached(prot)	(__pgprot(pgprot_val(prot) & ~_PAGE_CACHEABLE))
 
-static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
-			      pte_t *ptep, pte_t pteval)
-{
-	set_pte(ptep, pteval);
-}
-
-/*
- * Macro to quickly access the PGD entry, utlising the fact that some
- * arch may cache the pointer to Page Directory of "current" task
- * in a MMU register
- *
- * Thus task->mm->pgd (3 pointer dereferences, cache misses etc simply
- * becomes read a register
- *
- * ********CAUTION*******:
- * Kernel code might be dealing with some mm_struct of NON "current"
- * Thus use this macro only when you are certain that "current" is current
- * e.g. when dealing with signal frame setup code etc
- */
-#ifdef ARC_USE_SCRATCH_REG
-#define pgd_offset_fast(mm, addr)	\
-({					\
-	pgd_t *pgd_base = (pgd_t *) read_aux_reg(ARC_REG_SCRATCH_DATA0);  \
-	pgd_base + pgd_index(addr);	\
-})
-#else
-#define pgd_offset_fast(mm, addr)	pgd_offset(mm, addr)
-#endif
-
 extern pgd_t swapper_pg_dir[] __aligned(PAGE_SIZE);
-void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
-		      pte_t *ptep);
-
-/* Encode swap {type,off} tuple into PTE
- * We reserve 13 bits for 5-bit @type, keeping bits 12-5 zero, ensuring that
- * PAGE_PRESENT is zero in a PTE holding swap "identifier"
- */
-#define __swp_entry(type, off)	((swp_entry_t) { \
-					((type) & 0x1f) | ((off) << 13) })
-
-/* Decode a PTE containing swap "identifier "into constituents */
-#define __swp_type(pte_lookalike)	(((pte_lookalike).val) & 0x1f)
-#define __swp_offset(pte_lookalike)	((pte_lookalike).val >> 13)
-
-/* NOPs, to keep generic kernel happy */
-#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
-#define __swp_entry_to_pte(x)	((pte_t) { (x).val })
-
-#define kern_addr_valid(addr)	(1)
-
-#define pmd_pgtable(pmd)       ((pgtable_t) pmd_page_vaddr(pmd))
-
-/*
- * remap a physical page `pfn' of size `size' with page protection `prot'
- * into virtual address `from'
- */
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-#include <asm/hugepage.h>
-#endif
 
 /* to cope with aliasing VIPT cache */
 #define HAVE_ARCH_UNMAPPED_AREA

arch/arc/include/asm/processor.h

···
 #define VMALLOC_START	(PAGE_OFFSET - (CONFIG_ARC_KVADDR_SIZE << 20))
 
 /* 1 PGDIR_SIZE each for fixmap/pkmap, 2 PGDIR_SIZE gutter (see asm/highmem.h) */
-#define VMALLOC_SIZE	((CONFIG_ARC_KVADDR_SIZE << 20) - PGDIR_SIZE * 4)
+#define VMALLOC_SIZE	((CONFIG_ARC_KVADDR_SIZE << 20) - PMD_SIZE * 4)
 
 #define VMALLOC_END	(VMALLOC_START + VMALLOC_SIZE)
 

arch/arc/include/asm/setup.h

···
 /*
  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
  */
-#ifndef __ASMARC_SETUP_H
-#define __ASMARC_SETUP_H
+#ifndef __ASM_ARC_SETUP_H
+#define __ASM_ARC_SETUP_H
 
 
 #include <linux/types.h>
···
 #define IS_USED_CFG(cfg)	IS_USED_RUN(IS_ENABLED(cfg))
 #define IS_AVAIL2(v, s, cfg)	IS_AVAIL1(v, s), IS_AVAIL1(v, IS_USED_CFG(cfg))
 #define IS_AVAIL3(v, v2, s)	IS_AVAIL1(v, s), IS_AVAIL1(v, IS_DISABLED_RUN(v2))
+
+extern void arc_mmu_init(void);
+extern char *arc_mmu_mumbojumbo(int cpu_id, char *buf, int len);
+extern void read_decode_mmu_bcr(void);
+
+extern void arc_cache_init(void);
+extern char *arc_cache_mumbojumbo(int cpu_id, char *buf, int len);
+extern void read_decode_cache_bcr(void);
 
 #endif /* __ASMARC_SETUP_H */

arch/arc/include/asm/smp.h

···
 #include <asm/spinlock.h>
 
 extern arch_spinlock_t smp_atomic_ops_lock;
-extern arch_spinlock_t smp_bitops_lock;
 
 #define atomic_ops_lock(flags)	do {		\
 	local_irq_save(flags);			\
···
 	local_irq_restore(flags);		\
 } while (0)
 
-#define bitops_lock(flags)	do {		\
-	local_irq_save(flags);			\
-	arch_spin_lock(&smp_bitops_lock);	\
-} while (0)
-
-#define bitops_unlock(flags) do {		\
-	arch_spin_unlock(&smp_bitops_lock);	\
-	local_irq_restore(flags);		\
-} while (0)
-
 #else /* !CONFIG_SMP */
 
 #define atomic_ops_lock(flags)		local_irq_save(flags)
 #define atomic_ops_unlock(flags)	local_irq_restore(flags)
-
-#define bitops_lock(flags)		local_irq_save(flags)
-#define bitops_unlock(flags)		local_irq_restore(flags)
 
 #endif /* !CONFIG_SMP */
 

arch/arc/include/asm/tlb-mmu1.h

···
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
- */
-
-#ifndef __ASM_TLB_MMU_V1_H__
-#define __ASM_TLB_MMU_V1_H__
-
-#include <asm/mmu.h>
-
-#if defined(__ASSEMBLY__) && (CONFIG_ARC_MMU_VER == 1)
-
-.macro TLB_WRITE_HEURISTICS
-
-#define JH_HACK1
-#undef JH_HACK2
-#undef JH_HACK3
-
-#ifdef JH_HACK3
-; Calculate set index for 2-way MMU
-; -avoiding use of GetIndex from MMU
-;   and its unpleasant LFSR pseudo-random sequence
-;
-; r1 = TLBPD0 from TLB_RELOAD above
-;
-; -- jh_ex_way_set not cleared on startup
-;    didn't want to change setup.c
-;    hence extra instruction to clean
-;
-; -- should be in cache since in same line
-;    as r0/r1 saves above
-;
-ld  r0,[jh_ex_way_sel]  ; victim pointer
-and r0,r0,1         ; clean
-xor.f   r0,r0,1         ; flip
-st  r0,[jh_ex_way_sel]  ; store back
-asr r0,r1,12        ; get set # <<1, note bit 12=R=0
-or.nz   r0,r0,1         ; set way bit
-and r0,r0,0xff      ; clean
-sr  r0,[ARC_REG_TLBINDEX]
-#endif
-
-#ifdef JH_HACK2
-; JH hack #2
-;  Faster than hack #1 in non-thrash case, but hard-coded for 2-way MMU
-;  Slower in thrash case (where it matters) because more code is executed
-;  Inefficient due to two-register paradigm of this miss handler
-;
-/* r1 = data TLBPD0 at this point */
-lr      r0,[eret]               /* instruction address */
-xor     r0,r0,r1                /* compare set #       */
-and.f   r0,r0,0x000fe000        /* 2-way MMU mask      */
-bne     88f                     /* not in same set - no need to probe */
-
-lr      r0,[eret]               /* instruction address */
-and     r0,r0,PAGE_MASK         /* VPN of instruction address */
-; lr  r1,[ARC_REG_TLBPD0]     /* Data VPN+ASID - already in r1 from TLB_RELOAD*/
-and     r1,r1,0xff              /* Data ASID */
-or      r0,r0,r1                /* Instruction address + Data ASID */
-
-lr      r1,[ARC_REG_TLBPD0]     /* save TLBPD0 containing data TLB*/
-sr      r0,[ARC_REG_TLBPD0]     /* write instruction address to TLBPD0 */
-sr      TLBProbe, [ARC_REG_TLBCOMMAND] /* Look for instruction */
-lr      r0,[ARC_REG_TLBINDEX]   /* r0 = index where instruction is, if at all */
-sr      r1,[ARC_REG_TLBPD0]     /* restore TLBPD0 */
-
-xor     r0,r0,1                 /* flip bottom bit of data index */
-b.d     89f
-sr      r0,[ARC_REG_TLBINDEX]   /* and put it back */
-88:
-sr  TLBGetIndex, [ARC_REG_TLBCOMMAND]
-89:
-#endif
-
-#ifdef JH_HACK1
-;
-; Always checks whether instruction will be kicked out by dtlb miss
-;
-mov_s   r3, r1                  ; save PD0 prepared by TLB_RELOAD in r3
-lr      r0,[eret]               /* instruction address */
-and     r0,r0,PAGE_MASK         /* VPN of instruction address */
-bmsk    r1,r3,7                 /* Data ASID, bits 7-0 */
-or_s    r0,r0,r1                /* Instruction address + Data ASID */
-
-sr      r0,[ARC_REG_TLBPD0]     /* write instruction address to TLBPD0 */
-sr      TLBProbe, [ARC_REG_TLBCOMMAND] /* Look for instruction */
-lr      r0,[ARC_REG_TLBINDEX]   /* r0 = index where instruction is, if at all */
-sr      r3,[ARC_REG_TLBPD0]     /* restore TLBPD0 */
-
-sr      TLBGetIndex, [ARC_REG_TLBCOMMAND]
-lr      r1,[ARC_REG_TLBINDEX]   /* r1 = index where MMU wants to put data */
-cmp     r0,r1                   /* if no match on indices, go around */
-xor.eq  r1,r1,1                 /* flip bottom bit of data index */
-sr      r1,[ARC_REG_TLBINDEX]   /* and put it back */
-#endif
-
-.endm
-
-#endif
-
-#endif

arch/arc/kernel/entry-arcv2.S

···
 #include <asm/errno.h>
 #include <asm/arcregs.h>
 #include <asm/irqflags.h>
+#include <asm/mmu.h>
 
 ; A maximum number of supported interrupts in the core interrupt controller.
 ; This number is not equal to the maximum interrupt number (256) because

arch/arc/kernel/entry.S

···
 	lr  r0, [efa]
 	mov r1, sp
 
-	; hardware auto-disables MMU, re-enable it to allow kernel vaddr
-	; access for say stack unwinding of modules for crash dumps
-	lr	r3, [ARC_REG_PID]
-	or	r3, r3, MMU_ENABLE
-	sr	r3, [ARC_REG_PID]
+	; MC excpetions disable MMU
+	ARC_MMU_REENABLE r3
 
 	lsr  	r3, r2, 8
 	bmsk 	r3, r3, 7

arch/arc/kernel/intc-compact.c

···
  *    Time hard-ISR, timer_interrupt( ) calls spin_unlock_irq several times.
  *    Here local_irq_enable( ) shd not re-enable lower priority interrupts
  * -If called from soft-ISR, it must re-enable all interrupts
- *    soft ISR are low prioity jobs which can be very slow, thus all IRQs
+ *    soft ISR are low priority jobs which can be very slow, thus all IRQs
  *    must be enabled while they run.
  *    Now hardware context wise we may still be in L2 ISR (not done rtie)
  *    still we must re-enable both L1 and L2 IRQs

arch/arc/kernel/smp.c

···
 
 #ifndef CONFIG_ARC_HAS_LLSC
 arch_spinlock_t smp_atomic_ops_lock = __ARCH_SPIN_LOCK_UNLOCKED;
-arch_spinlock_t smp_bitops_lock = __ARCH_SPIN_LOCK_UNLOCKED;
 
 EXPORT_SYMBOL_GPL(smp_atomic_ops_lock);
-EXPORT_SYMBOL_GPL(smp_bitops_lock);
 #endif
 
 struct plat_smp_ops  __weak plat_smp_ops;
···
 	/*
 	 * Call the platform specific IPI kick function, but avoid if possible:
 	 * Only do so if there's no pending msg from other concurrent sender(s).
-	 * Otherwise, recevier will see this msg as well when it takes the
+	 * Otherwise, receiver will see this msg as well when it takes the
 	 * IPI corresponding to that msg. This is true, even if it is already in
 	 * IPI handler, because !@old means it has not yet dequeued the msg(s)
 	 * so @new msg can be a free-loader

arch/arc/kernel/stacktrace.c

···
 #else
 	/* On ARC, only Dward based unwinder works. fp based backtracing is
 	 * not possible (-fno-omit-frame-pointer) because of the way function
-	 * prelogue is setup (callee regs saved and then fp set and not other
+	 * prologue is setup (callee regs saved and then fp set and not other
 	 * way around
 	 */
 	pr_warn_once("CONFIG_ARC_DW2_UNWIND needs to be enabled\n");

arch/arc/mm/cache.c

···
 #define OP_INV_IC	0x4
 
 /*
- *		I-Cache Aliasing in ARC700 VIPT caches (MMU v1-v3)
+ * Cache Flush programming model
  *
- * ARC VIPT I-cache uses vaddr to index into cache and paddr to match the tag.
- * The orig Cache Management Module "CDU" only required paddr to invalidate a
- * certain line since it sufficed as index in Non-Aliasing VIPT cache-geometry.
- * Infact for distinct V1,V2,P: all of {V1-P},{V2-P},{P-P} would end up fetching
- * the exact same line.
+ * ARC700 MMUv3 I$ and D$ are both VIPT and can potentially alias.
+ * Programming model requires both paddr and vaddr irrespecive of aliasing
+ * considerations:
+ *  - vaddr in {I,D}C_IV?L
+ *  - paddr in {I,D}C_PTAG
  *
- * However for larger Caches (way-size > page-size) - i.e. in Aliasing config,
- * paddr alone could not be used to correctly index the cache.
+ * In HS38x (MMUv4), D$ is PIPT, I$ is VIPT and can still alias.
+ * Programming model is different for aliasing vs. non-aliasing I$
+ *  - D$ / Non-aliasing I$: only paddr in {I,D}C_IV?L
+ *  - Aliasing I$: same as ARC700 above (so MMUv3 routine used for MMUv4 I$)
  *
- * ------------------
- * MMU v1/v2 (Fixed Page Size 8k)
- * ------------------
- * The solution was to provide CDU with these additonal vaddr bits. These
- * would be bits [x:13], x would depend on cache-geometry, 13 comes from
- * standard page size of 8k.
- * H/w folks chose [17:13] to be a future safe range, and moreso these 5 bits
- * of vaddr could easily be "stuffed" in the paddr as bits [4:0] since the
- * orig 5 bits of paddr were anyways ignored by CDU line ops, as they
- * represent the offset within cache-line. The adv of using this "clumsy"
- * interface for additional info was no new reg was needed in CDU programming
- * model.
- *
- * 17:13 represented the max num of bits passable, actual bits needed were
- * fewer, based on the num-of-aliases possible.
- * -for 2 alias possibility, only bit 13 needed (32K cache)
- * -for 4 alias possibility, bits 14:13 needed (64K cache)
- *
- * ------------------
- * MMU v3
- * ------------------
- * This ver of MMU supports variable page sizes (1k-16k): although Linux will
- * only support 8k (default), 16k and 4k.
- * However from hardware perspective, smaller page sizes aggravate aliasing
- * meaning more vaddr bits needed to disambiguate the cache-line-op ;
- * the existing scheme of piggybacking won't work for certain configurations.
- * Two new registers IC_PTAG and DC_PTAG inttoduced.
- * "tag" bits are provided in PTAG, index bits in existing IVIL/IVDL/FLDL regs
+ *  - If PAE40 is enabled, independent of aliasing considerations, the higher
+ *    bits needs to be written into PTAG_HI
  */
 
-static inline
-void __cache_line_loop_v2(phys_addr_t paddr, unsigned long vaddr,
-			  unsigned long sz, const int op, const int full_page)
-{
-	unsigned int aux_cmd;
-	int num_lines;
-
-	if (op == OP_INV_IC) {
-		aux_cmd = ARC_REG_IC_IVIL;
-	} else {
-		/* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
-		aux_cmd = op & OP_INV ? ARC_REG_DC_IVDL : ARC_REG_DC_FLDL;
-	}
-
-	/* Ensure we properly floor/ceil the non-line aligned/sized requests
-	 * and have @paddr - aligned to cache line and integral @num_lines.
-	 * This however can be avoided for page sized since:
-	 *  -@paddr will be cache-line aligned already (being page aligned)
-	 *  -@sz will be integral multiple of line size (being page sized).
-	 */
-	if (!full_page) {
-		sz += paddr & ~CACHE_LINE_MASK;
-		paddr &= CACHE_LINE_MASK;
-		vaddr &= CACHE_LINE_MASK;
-	}
-
-	num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES);
-
-	/* MMUv2 and before: paddr contains stuffed vaddrs bits */
-	paddr |= (vaddr >> PAGE_SHIFT) & 0x1F;
-
-	while (num_lines-- > 0) {
-		write_aux_reg(aux_cmd, paddr);
-		paddr += L1_CACHE_BYTES;
-	}
-}
-
-/*
- * For ARC700 MMUv3 I-cache and D-cache flushes
- *  - ARC700 programming model requires paddr and vaddr be passed in seperate
- *    AUX registers (*_IV*L and *_PTAG respectively) irrespective of whether the
- *    caches actually alias or not.
- * -  For HS38, only the aliasing I-cache configuration uses the PTAG reg
- *    (non aliasing I-cache version doesn't; while D-cache can't possibly alias)
- */
 static inline
 void __cache_line_loop_v3(phys_addr_t paddr, unsigned long vaddr,
 			  unsigned long sz, const int op, const int full_page)
···
 #ifndef USE_RGN_FLSH
 
 /*
- * In HS38x (MMU v4), I-cache is VIPT (can alias), D-cache is PIPT
- * Here's how cache ops are implemented
- *
- *  - D-cache: only paddr needed (in DC_IVDL/DC_FLDL)
- *  - I-cache Non Aliasing: Despite VIPT, only paddr needed (in IC_IVIL)
- *  - I-cache Aliasing: Both vaddr and paddr needed (in IC_IVIL, IC_PTAG
- *    respectively, similar to MMU v3 programming model, hence
- *    __cache_line_loop_v3() is used)
- *
- * If PAE40 is enabled, independent of aliasing considerations, the higher bits
- * needs to be written into PTAG_HI
  */
 static inline
 void __cache_line_loop_v4(phys_addr_t paddr, unsigned long vaddr,
···
 
 #endif
 
-#if (CONFIG_ARC_MMU_VER < 3)
-#define __cache_line_loop	__cache_line_loop_v2
-#elif (CONFIG_ARC_MMU_VER == 3)
+#ifdef CONFIG_ARC_MMU_V3
 #define __cache_line_loop	__cache_line_loop_v3
-#elif (CONFIG_ARC_MMU_VER > 3)
+#else
 #define __cache_line_loop	__cache_line_loop_v4
 #endif
 
···
 	clear_page(to);
 	clear_bit(PG_dc_clean, &page->flags);
 }
-
+EXPORT_SYMBOL(clear_user_page);
 
 /**********************************************************************
  * Explicit Cache flush request from user space via syscall

arch/arc/mm/fault.c

···
 	pud_t *pud, *pud_k;
 	pmd_t *pmd, *pmd_k;
 
-	pgd = pgd_offset_fast(current->active_mm, address);
+	pgd = pgd_offset(current->active_mm, address);
 	pgd_k = pgd_offset_k(address);
 
-	if (!pgd_present(*pgd_k))
+	if (pgd_none (*pgd_k))
 		goto bad_area;
+	if (!pgd_present(*pgd))
+		set_pgd(pgd, *pgd_k);
 
 	p4d = p4d_offset(pgd, address);
 	p4d_k = p4d_offset(pgd_k, address);
-	if (!p4d_present(*p4d_k))
+	if (p4d_none(*p4d_k))
 		goto bad_area;
+	if (!p4d_present(*p4d))
+		set_p4d(p4d, *p4d_k);
 
 	pud = pud_offset(p4d, address);
 	pud_k = pud_offset(p4d_k, address);
-	if (!pud_present(*pud_k))
+	if (pud_none(*pud_k))
 		goto bad_area;
+	if (!pud_present(*pud))
+		set_pud(pud, *pud_k);
 
 	pmd = pmd_offset(pud, address);
 	pmd_k = pmd_offset(pud_k, address);
-	if (!pmd_present(*pmd_k))
+	if (pmd_none(*pmd_k))
 		goto bad_area;
-
-	set_pmd(pmd, *pmd_k);
+	if (!pmd_present(*pmd))
+		set_pmd(pmd, *pmd_k);
 
 	/* XXX: create the TLB entry here */
 	return 0;

arch/arc/mm/init.c

···
 {
 	memblock_free_all();
 	highmem_init();
+
+	BUILD_BUG_ON((PTRS_PER_PGD * sizeof(pgd_t)) > PAGE_SIZE);
+	BUILD_BUG_ON((PTRS_PER_PUD * sizeof(pud_t)) > PAGE_SIZE);
+	BUILD_BUG_ON((PTRS_PER_PMD * sizeof(pmd_t)) > PAGE_SIZE);
+	BUILD_BUG_ON((PTRS_PER_PTE * sizeof(pte_t)) > PAGE_SIZE);
 }
 
 #ifdef CONFIG_HIGHMEM

arch/arc/mm/ioremap.c

···
 	if (arc_uncached_addr_space(paddr))
 		return (void __iomem *)(u32)paddr;
 
-	return ioremap_prot(paddr, size, PAGE_KERNEL_NO_CACHE);
+	return ioremap_prot(paddr, size,
+			    pgprot_val(pgprot_noncached(PAGE_KERNEL)));
 }
 EXPORT_SYMBOL(ioremap);
 

arch/arc/mm/tlb.c

···
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * TLB Management (flush/create/diagnostics) for ARC700
+ * TLB Management (flush/create/diagnostics) for MMUv3 and MMUv4
  *
  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
  *
- * vineetg: Aug 2011
- *  -Reintroduce duplicate PD fixup - some customer chips still have the issue
- *
- * vineetg: May 2011
- *  -No need to flush_cache_page( ) for each call to update_mmu_cache()
- *   some of the LMBench tests improved amazingly
- *      = page-fault thrice as fast (75 usec to 28 usec)
- *      = mmap twice as fast (9.6 msec to 4.6 msec),
- *      = fork (5.3 msec to 3.7 msec)
- *
- * vineetg: April 2011 :
- *  -MMU v3: PD{0,1} bits layout changed: They don't overlap anymore,
- *      helps avoid a shift when preparing PD0 from PTE
- *
- * vineetg: April 2011 : Preparing for MMU V3
- *  -MMU v2/v3 BCRs decoded differently
- *  -Remove TLB_SIZE hardcoding as it's variable now: 256 or 512
- *  -tlb_entry_erase( ) can be void
- *  -local_flush_tlb_range( ):
- *      = need not "ceil" @end
- *      = walks MMU only if range spans < 32 entries, as opposed to 256
- *
- * Vineetg: Sept 10th 2008
- *  -Changes related to MMU v2 (Rel 4.8)
- *
- * Vineetg: Aug 29th 2008
- *  -In TLB Flush operations (Metal Fix MMU) there is a explicit command to
- *    flush Micro-TLBS. If TLB Index Reg is invalid prior to TLBIVUTLB cmd,
- *    it fails. Thus need to load it with ANY valid value before invoking
- *    TLBIVUTLB cmd
- *
- * Vineetg: Aug 21th 2008:
- *  -Reduced the duration of IRQ lockouts in TLB Flush routines
- *  -Multiple copies of TLB erase code separated into a "single" function
- *  -In TLB Flush routines, interrupt disabling moved UP to retrieve ASID
- *       in interrupt-safe region.
- *
- * Vineetg: April 23rd Bug #93131
- *    Problem: tlb_flush_kernel_range() doesn't do anything if the range to
- *              flush is more than the size of TLB itself.
- *
- * Rahul Trivedi : Codito Technologies 2004
  */
 
 #include <linux/module.h>
···
 #include <asm/setup.h>
 #include <asm/mmu_context.h>
 #include <asm/mmu.h>
-
-/*			Need for ARC MMU v2
- *
- * ARC700 MMU-v1 had a Joint-TLB for Code and Data and is 2 way set-assoc.
- * For a memcpy operation with 3 players (src/dst/code) such that all 3 pages
- * map into same set, there would be contention for the 2 ways causing severe
- * Thrashing.
- *
- * Although J-TLB is 2 way set assoc, ARC700 caches J-TLB into uTLBS which has
- * much higher associativity. u-D-TLB is 8 ways, u-I-TLB is 4 ways.
- * Given this, the thrashing problem should never happen because once the 3
- * J-TLB entries are created (even though 3rd will knock out one of the prev
- * two), the u-D-TLB and u-I-TLB will have what is required to accomplish memcpy
- *
- * Yet we still see the Thrashing because a J-TLB Write cause flush of u-TLBs.
- * This is a simple design for keeping them in sync. So what do we do?
- * The solution which James came up was pretty neat. It utilised the assoc
- * of uTLBs by not invalidating always but only when absolutely necessary.
- *
- * - Existing TLB commands work as before
- * - New command (TLBWriteNI) for TLB write without clearing uTLBs
- * - New command (TLBIVUTLB) to invalidate uTLBs.
- *
- * The uTLBs need only be invalidated when pages are being removed from the
- * OS page table. If a 'victim' TLB entry is being overwritten in the main TLB
- * as a result of a miss, the removed entry is still allowed to exist in the
- * uTLBs as it is still valid and present in the OS page table. This allows the
- * full associativity of the uTLBs to hide the limited associativity of the main
- * TLB.
- *
- * During a miss handler, the new "TLBWriteNI" command is used to load
- * entries without clearing the uTLBs.
- *
- * When the OS page table is updated, TLB entries that may be associated with a
- * removed page are removed (flushed) from the TLB using TLBWrite. In this
- * circumstance, the uTLBs must also be cleared. This is done by using the
- * existing TLBWrite command. An explicit IVUTLB is also required for those
- * corner cases when TLBWrite was not executed at all because the corresp
- * J-TLB entry got evicted/replaced.
- */
-
 
 /* A copy of the ASID from the PID reg is kept in asid_cache */
 DEFINE_PER_CPU(unsigned int, asid_cache) = MM_CTXT_FIRST_CYCLE;
···
 
 static void utlb_invalidate(void)
 {
-#if (CONFIG_ARC_MMU_VER >= 2)
-
-#if (CONFIG_ARC_MMU_VER == 2)
-	/* MMU v2 introduced the uTLB Flush command.
-	 * There was however an obscure hardware bug, where uTLB flush would
-	 * fail when a prior probe for J-TLB (both totally unrelated) would
-	 * return lkup err - because the entry didn't exist in MMU.
-	 * The Workaround was to set Index reg with some valid value, prior to
-	 * flush. This was fixed in MMU v3
-	 */
-	unsigned int idx;
-
-	/* make sure INDEX Reg is valid */
-	idx = read_aux_reg(ARC_REG_TLBINDEX);
-
-	/* If not write some dummy val */
-	if (unlikely(idx & TLB_LKUP_ERR))
-		write_aux_reg(ARC_REG_TLBINDEX, 0xa);
-#endif
-
 	write_aux_reg(ARC_REG_TLBCOMMAND, TLBIVUTLB);
-#endif
-
 }
 
-#if (CONFIG_ARC_MMU_VER < 4)
+#ifdef CONFIG_ARC_MMU_V3
 
 static inline unsigned int tlb_entry_lkup(unsigned long vaddr_n_asid)
 {
···
 	}
 }
 
-static void tlb_entry_insert(unsigned int pd0, pte_t pd1)
+static void tlb_entry_insert(unsigned int pd0, phys_addr_t pd1)
 {
 	unsigned int idx;
 
···
 	write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite);
 }
 
-#else	/* CONFIG_ARC_MMU_VER >= 4) */
+#else	/* MMUv4 */
 
 static void tlb_entry_erase(unsigned int vaddr_n_asid)
 {
···
 	write_aux_reg(ARC_REG_TLBCOMMAND, TLBDeleteEntry);
 }
 
-static void tlb_entry_insert(unsigned int pd0, pte_t pd1)
+static void tlb_entry_insert(unsigned int pd0, phys_addr_t pd1)
 {
 	write_aux_reg(ARC_REG_TLBPD0, pd0);
-	write_aux_reg(ARC_REG_TLBPD1, pd1);
 
-	if (is_pae40_enabled())
+	if (!is_pae40_enabled()) {
+		write_aux_reg(ARC_REG_TLBPD1, pd1);
+	} else {
+		write_aux_reg(ARC_REG_TLBPD1, pd1 & 0xFFFFFFFF);
 		write_aux_reg(ARC_REG_TLBPD1HI, (u64)pd1 >> 32);
+	}
 
 	write_aux_reg(ARC_REG_TLBCOMMAND, TLBInsertEntry);
 }
···
 	unsigned long flags;
 	unsigned int asid_or_sasid, rwx;
 	unsigned long pd0;
-	pte_t pd1;
+	phys_addr_t pd1;
 
 	/*
 	 * create_tlb() assumes that current->mm == vma->mm, since
···
 	 *
 	 * Removing the assumption involves
 	 * -Using vma->mm->context{ASID,SASID}, as opposed to MMU reg.
-	 * -Fix the TLB paranoid debug code to not trigger false negatives.
 	 * -More importantly it makes this handler inconsistent with fast-path
 	 *  TLB Refill handler which always deals with "current"
 	 *
···
 		return;
 
 	local_irq_save(flags);
-
-	tlb_paranoid_check(asid_mm(vma->vm_mm, smp_processor_id()), vaddr);
 
 	vaddr &= PAGE_MASK;
 
···
 	update_mmu_cache(vma, addr, &pte);
 }
 
-void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
-				pgtable_t pgtable)
-{
-	struct list_head *lh = (struct list_head *) pgtable;
-
-	assert_spin_locked(&mm->page_table_lock);
-
-	/* FIFO */
-	if (!pmd_huge_pte(mm, pmdp))
-		INIT_LIST_HEAD(lh);
-	else
-		list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp));
-	pmd_huge_pte(mm, pmdp) = pgtable;
-}
-
-pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
-{
-	struct list_head *lh;
-	pgtable_t pgtable;
-
-	assert_spin_locked(&mm->page_table_lock);
-
-	pgtable = pmd_huge_pte(mm, pmdp);
-	lh = (struct list_head *) pgtable;
-	if (list_empty(lh))
-		pmd_huge_pte(mm, pmdp) = NULL;
-	else {
-		pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next;
-		list_del(lh);
-	}
-
-	pte_val(pgtable[0]) = 0;
-	pte_val(pgtable[1]) = 0;
-
-	return pgtable;
-}
-
 void local_flush_pmd_tlb_range(struct vm_area_struct *vma, unsigned long start,
 			       unsigned long end)
 {
···
 {
 	struct cpuinfo_arc_mmu *mmu = &cpuinfo_arc700[smp_processor_id()].mmu;
 	unsigned int tmp;
-	struct bcr_mmu_1_2 {
-#ifdef CONFIG_CPU_BIG_ENDIAN
-		unsigned int ver:8, ways:4, sets:4, u_itlb:8, u_dtlb:8;
-#else
-		unsigned int u_dtlb:8, u_itlb:8, sets:4, ways:4, ver:8;
-#endif
-	} *mmu2;
-
 	struct bcr_mmu_3 {
 #ifdef CONFIG_CPU_BIG_ENDIAN
 	unsigned int ver:8, ways:4, sets:4, res:3, sasid:1, pg_sz:4,
···
 	tmp = read_aux_reg(ARC_REG_MMU_BCR);
 	mmu->ver = (tmp >> 24);
 
-	if (is_isa_arcompact()) {
-		if (mmu->ver <= 2) {
-			mmu2 = (struct bcr_mmu_1_2 *)&tmp;
-			mmu->pg_sz_k = TO_KB(0x2000);
-			mmu->sets = 1 << mmu2->sets;
-			mmu->ways = 1 << mmu2->ways;
-			mmu->u_dtlb = mmu2->u_dtlb;
-			mmu->u_itlb = mmu2->u_itlb;
-		} else {
-			mmu3 = (struct bcr_mmu_3 *)&tmp;
-			mmu->pg_sz_k = 1 << (mmu3->pg_sz - 1);
-			mmu->sets = 1 << mmu3->sets;
-			mmu->ways = 1 << mmu3->ways;
-			mmu->u_dtlb = mmu3->u_dtlb;
-			mmu->u_itlb = mmu3->u_itlb;
-			mmu->sasid = mmu3->sasid;
-		}
+	if (is_isa_arcompact() && mmu->ver == 3) {
+		mmu3 = (struct bcr_mmu_3 *)&tmp;
+		mmu->pg_sz_k = 1 << (mmu3->pg_sz - 1);
+		mmu->sets = 1 << mmu3->sets;
+		mmu->ways = 1 << mmu3->ways;
+		mmu->u_dtlb = mmu3->u_dtlb;
+		mmu->u_itlb = mmu3->u_itlb;
+		mmu->sasid = mmu3->sasid;
 	} else {
 		mmu4 = (struct bcr_mmu_4 *)&tmp;
 		mmu->pg_sz_k = 1 << (mmu4->sz0 - 1);
···
 			  IS_USED_CFG(CONFIG_TRANSPARENT_HUGEPAGE));
 
 	n += scnprintf(buf + n, len - n,
-		      "MMU [v%x]\t: %dk PAGE, %sJTLB %d (%dx%d), uDTLB %d, uITLB %d%s%s\n",
-		       p_mmu->ver, p_mmu->pg_sz_k, super_pg,
+		      "MMU [v%x]\t: %dk PAGE, %s, swalk %d lvl, JTLB %d (%dx%d), uDTLB %d, uITLB %d%s%s\n",
+		       p_mmu->ver, p_mmu->pg_sz_k, super_pg,  CONFIG_PGTABLE_LEVELS,
 		       p_mmu->sets * p_mmu->ways, p_mmu->sets, p_mmu->ways,
 		       p_mmu->u_dtlb, p_mmu->u_itlb,
 		       IS_AVAIL2(p_mmu->pae, ", PAE40 ", CONFIG_ARC_HAS_PAE40));
···
 
 	/*
 	 * Ensure that MMU features assumed by kernel exist in hardware.
-	 * For older ARC700 cpus, it has to be exact match, since the MMU
-	 * revisions were not backwards compatible (MMUv3 TLB layout changed
-	 * so even if kernel for v2 didn't use any new cmds of v3, it would
-	 * still not work.
-	 * For HS cpus, MMUv4 was baseline and v5 is backwards compatible
-	 * (will run older software).
+	 *  - For older ARC700 cpus, only v3 supported
+	 *  - For HS cpus, v4 was baseline and v5 is backwards compatible
+	 *    (will run older software).
 	 */
-	if (is_isa_arcompact() && mmu->ver == CONFIG_ARC_MMU_VER)
+	if (is_isa_arcompact() && mmu->ver == 3)
 		compat = 1;
-	else if (is_isa_arcv2() && mmu->ver >= CONFIG_ARC_MMU_VER)
+	else if (is_isa_arcv2() && mmu->ver >= 4)
 		compat = 1;
 
-	if (!compat) {
-		panic("MMU ver %d doesn't match kernel built for %d...\n",
-		      mmu->ver, CONFIG_ARC_MMU_VER);
-	}
+	if (!compat)
+		panic("MMU ver %d doesn't match kernel built for\n", mmu->ver);
 
 	if (mmu->pg_sz_k != TO_KB(PAGE_SIZE))
 		panic("MMU pg size != PAGE_SIZE (%luk)\n", TO_KB(PAGE_SIZE));
···
 	if (IS_ENABLED(CONFIG_ARC_HAS_PAE40) && !mmu->pae)
 		panic("Hardware doesn't support PAE40\n");
 
-	/* Enable the MMU */
-	write_aux_reg(ARC_REG_PID, MMU_ENABLE);
+	/* Enable the MMU with ASID 0 */
+	mmu_setup_asid(NULL, 0);
 
-	/* In smp we use this reg for interrupt 1 scratch */
-#ifdef ARC_USE_SCRATCH_REG
-	/* swapper_pg_dir is the pgd for the kernel, used by vmalloc */
-	write_aux_reg(ARC_REG_SCRATCH_DATA0, swapper_pg_dir);
-#endif
+	/* cache the pgd pointer in MMU SCRATCH reg (ARCv2 only) */
+	mmu_setup_pgd(NULL, swapper_pg_dir);
 
 	if (pae40_exist_but_not_enab())
 		write_aux_reg(ARC_REG_TLBPD1HI, 0);
···
 
 	local_irq_restore(flags);
 }
-
-/***********************************************************************
- * Diagnostic Routines
- *  -Called from Low Level TLB Handlers if things don;t look good
- **********************************************************************/
-
-#ifdef CONFIG_ARC_DBG_TLB_PARANOIA
-
-/*
- * Low Level ASM TLB handler calls this if it finds that HW and SW ASIDS
- * don't match
- */
-void print_asid_mismatch(int mm_asid, int mmu_asid, int is_fast_path)
-{
-	pr_emerg("ASID Mismatch in %s Path Handler: sw-pid=0x%x hw-pid=0x%x\n",
-	       is_fast_path ? "Fast" : "Slow", mm_asid, mmu_asid);
-
-	__asm__ __volatile__("flag 1");
-}
-
-void tlb_paranoid_check(unsigned int mm_asid, unsigned long addr)
-{
-	unsigned int mmu_asid;
-
-	mmu_asid = read_aux_reg(ARC_REG_PID) & 0xff;
-
-	/*
-	 * At the time of a TLB miss/installation
-	 *   - HW version needs to match SW version
-	 *   - SW needs to have a valid ASID
-	 */
-	if (addr < 0x70000000 &&
-	    ((mm_asid == MM_CTXT_NO_ASID) ||
-	      (mmu_asid != (mm_asid & MM_CTXT_ASID_MASK))))
-		print_asid_mismatch(mm_asid, mmu_asid, 0);
-}
-#endif

arch/arc/mm/tlbex.S

···
 #include <asm/arcregs.h>
 #include <asm/cache.h>
 #include <asm/processor.h>
-#include <asm/tlb-mmu1.h>
 
 #ifdef CONFIG_ISA_ARCOMPACT
 ;-----------------------------------------------------------------
···
 	st_s  r1, [r0, 4]
 	st_s  r2, [r0, 8]
 	st_s  r3, [r0, 12]
-
-	; VERIFY if the ASID in MMU-PID Reg is same as
-	; one in Linux data structures
-
-	tlb_paranoid_check_asm
 .endm
 
 .macro TLBMISS_RESTORE_REGS
···
 #endif
 
 ;============================================================================
-;  Troubleshooting Stuff
-;============================================================================
-
-; Linux keeps ASID (Address Space ID) in task->active_mm->context.asid
-; When Creating TLB Entries, instead of doing 3 dependent loads from memory,
-; we use the MMU PID Reg to get current ASID.
-; In bizzare scenrios SW and HW ASID can get out-of-sync which is trouble.
-; So we try to detect this in TLB Mis shandler
-
-.macro tlb_paranoid_check_asm
-
-#ifdef CONFIG_ARC_DBG_TLB_PARANOIA
-
-	GET_CURR_TASK_ON_CPU  r3
-	ld r0, [r3, TASK_ACT_MM]
-	ld r0, [r0, MM_CTXT+MM_CTXT_ASID]
-	breq r0, 0, 55f	; Error if no ASID allocated
-
-	lr r1, [ARC_REG_PID]
-	and r1, r1, 0xFF
-
-	and r2, r0, 0xFF	; MMU PID bits only for comparison
-	breq r1, r2, 5f
-
-55:
-	; Error if H/w and S/w ASID don't match, but NOT if in kernel mode
-	lr  r2, [erstatus]
-	bbit0 r2, STATUS_U_BIT, 5f
-
-	; We sure are in troubled waters, Flag the error, but to do so
-	; need to switch to kernel mode stack to call error routine
-	GET_TSK_STACK_BASE   r3, sp
-
-	; Call printk to shoutout aloud
-	mov r2, 1
-	j print_asid_mismatch
-
-5:	; ASIDs match so proceed normally
-	nop
-
-#endif
-
-.endm
-
-;============================================================================
 ;TLB Miss handling Code
 ;============================================================================
+
+#ifndef PMD_SHIFT
+#define PMD_SHIFT PUD_SHIFT
+#endif
+
+#ifndef PUD_SHIFT
+#define PUD_SHIFT PGDIR_SHIFT
+#endif
 
 ;-----------------------------------------------------------------------------
 ; This macro does the page-table lookup for the faulting address.
···
 
 	lr  r2, [efa]
 
-#ifdef ARC_USE_SCRATCH_REG
+#ifdef CONFIG_ISA_ARCV2
 	lr  r1, [ARC_REG_SCRATCH_DATA0] ; current pgd
 #else
 	GET_CURR_TASK_ON_CPU  r1
···
 	ld.as   r3, [r1, r0]            ; PGD entry corresp to faulting addr
 	tst	r3, r3
 	bz	do_slow_path_pf         ; if no Page Table, do page fault
+
+#if CONFIG_PGTABLE_LEVELS > 3
+	lsr     r0, r2, PUD_SHIFT	; Bits for indexing into PUD
+	and	r0, r0, (PTRS_PER_PUD - 1)
+	ld.as	r1, [r3, r0]		; PMD entry
+	tst	r1, r1
+	bz	do_slow_path_pf
+	mov	r3, r1
+#endif
+
+#if CONFIG_PGTABLE_LEVELS > 2
+	lsr     r0, r2, PMD_SHIFT	; Bits for indexing into PMD
+	and	r0, r0, (PTRS_PER_PMD - 1)
+	ld.as	r1, [r3, r0]		; PMD entry
+	tst	r1, r1
+	bz	do_slow_path_pf
+	mov	r3, r1
+#endif
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 	and.f	0, r3, _PAGE_HW_SZ	; Is this Huge PMD (thp)
···
 ; Commit the TLB entry into MMU
 
 .macro COMMIT_ENTRY_TO_MMU
-#if (CONFIG_ARC_MMU_VER < 4)
+#ifdef CONFIG_ARC_MMU_V3
 
 	/* Get free TLB slot: Set = computed from vaddr, way = random */
 	sr  TLBGetIndex, [ARC_REG_TLBCOMMAND]
···
 	st_s    r0, [r1]                      ; Write back PTE
 
 	CONV_PTE_TO_TLB
-
-#if (CONFIG_ARC_MMU_VER == 1)
-	; MMU with 2 way set assoc J-TLB, needs some help in pathetic case of
-	; memcpy where 3 parties contend for 2 ways, ensuing a livelock.
-	; But only for old MMU or one with Metal Fix
-	TLB_WRITE_HEURISTICS
-#endif
 
 	COMMIT_ENTRY_TO_MMU
 	TLBMISS_RESTORE_REGS