Fix errata 411920

[Russell King - ARM Linux]

Catalin,

According to my reading of this errata, any "invalidate entire instruction
cache" operation can fail.  I'm not sure why the work-around is just
implemented for some of these operations, and not others.

Here's a patch which addresses the remaining operations.  Note that
the arch/arm/mm/context.c one is weird - it's flushing the BTB
twice - once using "c7, c5, 0" and again with "c7, c5, 6".  Is there
a a reason for this?

 arch/arm/include/asm/cacheflush.h |    5 +++++
 arch/arm/mm/context.c             |    4 ++--
 arch/arm/mm/flush.c               |   31 ++++++-------------------------
 3 files changed, 13 insertions(+), 27 deletions(-)

diff --git a/arch/arm/include/asm/cacheflush.h b/arch/arm/include/asm/cacheflush.h
index 3147f75..af0624c 100644
--- a/arch/arm/include/asm/cacheflush.h
+++ b/arch/arm/include/asm/cacheflush.h
@@ -412,9 +412,14 @@ extern void flush_dcache_page(struct page *);
 
 static inline void __flush_icache_all(void)
 {
+#ifdef CONFIG_ARM_ERRATA_411920
+	extern void v6_icache_inval_all(void);
+	v6_icache_inval_all();
+#else
 	asm("mcr	p15, 0, %0, c7, c5, 0	@ invalidate I-cache\n"
 	    :
 	    : "r" (0));
+#endif
 }
 
 #define ARCH_HAS_FLUSH_ANON_PAGE
diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c
index 6bda76a..d4f8275 100644
--- a/arch/arm/mm/context.c
+++ b/arch/arm/mm/context.c
@@ -50,8 +50,8 @@ void __new_context(struct mm_struct *mm)
 		isb();
 		flush_tlb_all();
 		if (icache_is_vivt_asid_tagged()) {
-			asm("mcr	p15, 0, %0, c7, c5, 0	@ invalidate I-cache\n"
-			    "mcr	p15, 0, %0, c7, c5, 6	@ flush BTAC/BTB\n"
+			__flush_icache_all();
+			asm("mcr	p15, 0, %0, c7, c5, 6	@ flush BTAC/BTB"
 			    :
 			    : "r" (0));
 			dsb();
diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index b279429..7f294f3 100644
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -18,10 +18,6 @@
 
 #include "mm.h"
 
-#ifdef CONFIG_ARM_ERRATA_411920
-extern void v6_icache_inval_all(void);
-#endif
-
 #ifdef CONFIG_CPU_CACHE_VIPT
 
 #define ALIAS_FLUSH_START	0xffff4000
@@ -35,16 +31,11 @@ static void flush_pfn_alias(unsigned long pfn, unsigned long vaddr)
 	flush_tlb_kernel_page(to);
 
 	asm(	"mcrr	p15, 0, %1, %0, c14\n"
-	"	mcr	p15, 0, %2, c7, c10, 4\n"
-#ifndef CONFIG_ARM_ERRATA_411920
-	"	mcr	p15, 0, %2, c7, c5, 0\n"
-#endif
+	"	mcr	p15, 0, %2, c7, c10, 4"
 	    :
 	    : "r" (to), "r" (to + PAGE_SIZE - L1_CACHE_BYTES), "r" (zero)
 	    : "cc");
-#ifdef CONFIG_ARM_ERRATA_411920
-	v6_icache_inval_all();
-#endif
+	__flush_icache_all();
 }
 
 void flush_cache_mm(struct mm_struct *mm)
@@ -57,16 +48,11 @@ void flush_cache_mm(struct mm_struct *mm)
 
 	if (cache_is_vipt_aliasing()) {
 		asm(	"mcr	p15, 0, %0, c7, c14, 0\n"
-		"	mcr	p15, 0, %0, c7, c10, 4\n"
-#ifndef CONFIG_ARM_ERRATA_411920
-		"	mcr	p15, 0, %0, c7, c5, 0\n"
-#endif
+		"	mcr	p15, 0, %0, c7, c10, 4"
 		    :
 		    : "r" (0)
 		    : "cc");
-#ifdef CONFIG_ARM_ERRATA_411920
-		v6_icache_inval_all();
-#endif
+		__flush_icache_all();
 	}
 }
 
@@ -81,16 +67,11 @@ void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned
 
 	if (cache_is_vipt_aliasing()) {
 		asm(	"mcr	p15, 0, %0, c7, c14, 0\n"
-		"	mcr	p15, 0, %0, c7, c10, 4\n"
-#ifndef CONFIG_ARM_ERRATA_411920
-		"	mcr	p15, 0, %0, c7, c5, 0\n"
-#endif
+		"	mcr	p15, 0, %0, c7, c10, 4"
 		    :
 		    : "r" (0)
 		    : "cc");
-#ifdef CONFIG_ARM_ERRATA_411920
-		v6_icache_inval_all();
-#endif
+		__flush_icache_all();
 	}
 }