csky: Support icache flush without specific instructions

Some CPUs don't support icache specific instructions to flush icache
lines in broadcast way. We use cpu control registers to flush local
icache and use IPI to notify other cores.

Signed-off-by: Guo Ren <[e-mail]>

arch/csky/Kconfig

···
 	bool "CPU has FPU coprocessor"
 	depends on CPU_CK807 || CPU_CK810 || CPU_CK860
 
+config CPU_HAS_ICACHE_INS
+	bool "CPU has Icache invalidate instructions"
+	depends on CPU_HAS_CACHEV2
+
 config CPU_HAS_TEE
 	bool "CPU has Trusted Execution Environment"
 	depends on CPU_CK810

arch/csky/include/asm/cache.h

···
 
 void icache_inv_range(unsigned long start, unsigned long end);
 void icache_inv_all(void);
+void local_icache_inv_all(void *priv);
 
 void dcache_wb_range(unsigned long start, unsigned long end);
 void dcache_wbinv_all(void);

arch/csky/mm/cachev1.c

···
 	cache_op_all(INS_CACHE|CACHE_INV, 0);
 }
 
+void local_icache_inv_all(void *priv)
+{
+	cache_op_all(INS_CACHE|CACHE_INV, 0);
+}
+
 void dcache_wb_range(unsigned long start, unsigned long end)
 {
 	cache_op_range(start, end, DATA_CACHE|CACHE_CLR, 0);

arch/csky/mm/cachev2.c

···
 
 #include <linux/spinlock.h>
 #include <linux/smp.h>
+#include <linux/mm.h>
 #include <asm/cache.h>
 #include <asm/barrier.h>
 
-inline void dcache_wb_line(unsigned long start)
+#define INS_CACHE		(1 << 0)
+#define CACHE_INV		(1 << 4)
+
+void local_icache_inv_all(void *priv)
 {
-	asm volatile("dcache.cval1 %0\n"::"r"(start):"memory");
+	mtcr("cr17", INS_CACHE|CACHE_INV);
 	sync_is();
 }
 
+void icache_inv_all(void)
+{
+	on_each_cpu(local_icache_inv_all, NULL, 1);
+}
+
+#ifdef CONFIG_CPU_HAS_ICACHE_INS
 void icache_inv_range(unsigned long start, unsigned long end)
 {
 	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
···
 		asm volatile("icache.iva %0\n"::"r"(i):"memory");
 	sync_is();
 }
-
-void icache_inv_all(void)
+#else
+void icache_inv_range(unsigned long start, unsigned long end)
 {
-	asm volatile("icache.ialls\n":::"memory");
+	icache_inv_all();
+}
+#endif
+
+inline void dcache_wb_line(unsigned long start)
+{
+	asm volatile("dcache.cval1 %0\n"::"r"(start):"memory");
 	sync_is();
 }
 
···
 		asm volatile("dcache.cval1 %0\n"::"r"(i):"memory");
 	sync_is();
 
-	i = start & ~(L1_CACHE_BYTES - 1);
-	for (; i < end; i += L1_CACHE_BYTES)
-		asm volatile("icache.iva %0\n"::"r"(i):"memory");
-	sync_is();
+	icache_inv_range(start, end);
 }
 EXPORT_SYMBOL(cache_wbinv_range);