powerpc/cell: Move data segment faulting code out of cell platform

__spu_trap_data_seg() currently contains code to determine the VSID and ESID
required for a particular EA and mm struct.

This code is generically useful for other co-processors. This moves the code of
the cell platform so it can be used by other powerpc code. It also adds 1TB
segment handling which Cell didn't support. The new function is called
copro_calculate_slb().

This also moves the internal struct spu_slb to a generic struct copro_slb which
is now used in the Cell and copro code. We use this new struct instead of
passing around esid and vsid parameters.

Signed-off-by: Ian Munsie <[e-mail]>
Signed-off-by: Michael Neuling <[e-mail]>
Signed-off-by: Michael Ellerman <[e-mail]>

arch/powerpc/include/asm/copro.h

···
 #ifndef _ASM_POWERPC_COPRO_H
 #define _ASM_POWERPC_COPRO_H
 
+struct copro_slb
+{
+	u64 esid, vsid;
+};
+
 int copro_handle_mm_fault(struct mm_struct *mm, unsigned long ea,
 			  unsigned long dsisr, unsigned *flt);
+
+int copro_calculate_slb(struct mm_struct *mm, u64 ea, struct copro_slb *slb);
 
 #endif /* _ASM_POWERPC_COPRO_H */

arch/powerpc/include/asm/mmu-hash64.h

···
 
 #ifndef __ASSEMBLY__
 
+static inline int slb_vsid_shift(int ssize)
+{
+	if (ssize == MMU_SEGSIZE_256M)
+		return SLB_VSID_SHIFT;
+	return SLB_VSID_SHIFT_1T;
+}
+
 static inline int segment_shift(int ssize)
 {
 	if (ssize == MMU_SEGSIZE_256M)

arch/powerpc/mm/copro_fault.c

···
 #include <linux/mm.h>
 #include <linux/export.h>
 #include <asm/reg.h>
+#include <asm/copro.h>
 
 /*
  * This ought to be kept in sync with the powerpc specific do_page_fault
···
 	return ret;
 }
 EXPORT_SYMBOL_GPL(copro_handle_mm_fault);
+
+int copro_calculate_slb(struct mm_struct *mm, u64 ea, struct copro_slb *slb)
+{
+	u64 vsid;
+	int psize, ssize;
+
+	slb->esid = (ea & ESID_MASK) | SLB_ESID_V;
+
+	switch (REGION_ID(ea)) {
+	case USER_REGION_ID:
+		pr_devel("%s: 0x%llx -- USER_REGION_ID\n", __func__, ea);
+		psize = get_slice_psize(mm, ea);
+		ssize = user_segment_size(ea);
+		vsid = get_vsid(mm->context.id, ea, ssize);
+		break;
+	case VMALLOC_REGION_ID:
+		pr_devel("%s: 0x%llx -- VMALLOC_REGION_ID\n", __func__, ea);
+		if (ea < VMALLOC_END)
+			psize = mmu_vmalloc_psize;
+		else
+			psize = mmu_io_psize;
+		ssize = mmu_kernel_ssize;
+		vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
+		break;
+	case KERNEL_REGION_ID:
+		pr_devel("%s: 0x%llx -- KERNEL_REGION_ID\n", __func__, ea);
+		psize = mmu_linear_psize;
+		ssize = mmu_kernel_ssize;
+		vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
+		break;
+	default:
+		pr_debug("%s: invalid region access at %016llx\n", __func__, ea);
+		return 1;
+	}
+
+	vsid = (vsid << slb_vsid_shift(ssize)) | SLB_VSID_USER;
+
+	vsid |= mmu_psize_defs[psize].sllp |
+		((ssize == MMU_SEGSIZE_1T) ? SLB_VSID_B_1T : 0);
+
+	slb->vsid = vsid;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(copro_calculate_slb);

arch/powerpc/mm/slb.c

···
 	return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot;
 }
 
-#define slb_vsid_shift(ssize)	\
-	((ssize) == MMU_SEGSIZE_256M? SLB_VSID_SHIFT: SLB_VSID_SHIFT_1T)
-
 static inline unsigned long mk_vsid_data(unsigned long ea, int ssize,
 					 unsigned long flags)
 {

arch/powerpc/platforms/cell/spu_base.c

···
 static DEFINE_SPINLOCK(spu_full_list_lock);
 static DEFINE_MUTEX(spu_full_list_mutex);
 
-struct spu_slb {
-	u64 esid, vsid;
-};
-
 void spu_invalidate_slbs(struct spu *spu)
 {
 	struct spu_priv2 __iomem *priv2 = spu->priv2;
···
 	}
 }
 
-static inline void spu_load_slb(struct spu *spu, int slbe, struct spu_slb *slb)
+static inline void spu_load_slb(struct spu *spu, int slbe, struct copro_slb *slb)
 {
 	struct spu_priv2 __iomem *priv2 = spu->priv2;
 
···
 
 static int __spu_trap_data_seg(struct spu *spu, unsigned long ea)
 {
-	struct mm_struct *mm = spu->mm;
-	struct spu_slb slb;
-	int psize;
+	struct copro_slb slb;
+	int ret;
 
-	pr_debug("%s\n", __func__);
-
-	slb.esid = (ea & ESID_MASK) | SLB_ESID_V;
-
-	switch(REGION_ID(ea)) {
-	case USER_REGION_ID:
-#ifdef CONFIG_PPC_MM_SLICES
-		psize = get_slice_psize(mm, ea);
-#else
-		psize = mm->context.user_psize;
-#endif
-		slb.vsid = (get_vsid(mm->context.id, ea, MMU_SEGSIZE_256M)
-				<< SLB_VSID_SHIFT) | SLB_VSID_USER;
-		break;
-	case VMALLOC_REGION_ID:
-		if (ea < VMALLOC_END)
-			psize = mmu_vmalloc_psize;
-		else
-			psize = mmu_io_psize;
-		slb.vsid = (get_kernel_vsid(ea, MMU_SEGSIZE_256M)
-				<< SLB_VSID_SHIFT) | SLB_VSID_KERNEL;
-		break;
-	case KERNEL_REGION_ID:
-		psize = mmu_linear_psize;
-		slb.vsid = (get_kernel_vsid(ea, MMU_SEGSIZE_256M)
-				<< SLB_VSID_SHIFT) | SLB_VSID_KERNEL;
-		break;
-	default:
-		/* Future: support kernel segments so that drivers
-		 * can use SPUs.
-		 */
-		pr_debug("invalid region access at %016lx\n", ea);
-		return 1;
-	}
-	slb.vsid |= mmu_psize_defs[psize].sllp;
+	ret = copro_calculate_slb(spu->mm, ea, &slb);
+	if (ret)
+		return ret;
 
 	spu_load_slb(spu, spu->slb_replace, &slb);
 
···
 	return 0;
 }
 
-static void __spu_kernel_slb(void *addr, struct spu_slb *slb)
+static void __spu_kernel_slb(void *addr, struct copro_slb *slb)
 {
 	unsigned long ea = (unsigned long)addr;
 	u64 llp;
···
  * Given an array of @nr_slbs SLB entries, @slbs, return non-zero if the
  * address @new_addr is present.
  */
-static inline int __slb_present(struct spu_slb *slbs, int nr_slbs,
+static inline int __slb_present(struct copro_slb *slbs, int nr_slbs,
 		void *new_addr)
 {
 	unsigned long ea = (unsigned long)new_addr;
···
 void spu_setup_kernel_slbs(struct spu *spu, struct spu_lscsa *lscsa,
 		void *code, int code_size)
 {
-	struct spu_slb slbs[4];
+	struct copro_slb slbs[4];
 	int i, nr_slbs = 0;
 	/* start and end addresses of both mappings */
 	void *addrs[] = {