[U-Boot] [PATCH] ARM1136: Fix cache_flush() error and correct cpu_init_crit() comments

[George G. Davis]

The ARM1136 cache_flush() function uses the "mcr p15, 0, rn, c7, c7, 0"
instruction which means "Invalidate Both Caches" when in fact the intent
is to "Clean and Invalidate Entire Data Cache".  So change the ARM1136
cache_flush() function to use the "mcr p15, 0, rn, c7, c7, 0 @ Clean &
invalidate D-Cache" instruction to insure that memory is consistent
with any dirty cache lines.

Also fix a couple of "flush v*" comments in ARM1136 cpu_init_crit() so
that they correctly describe the actual ARM1136 CP15 C7 Cache Operations
used.

Signed-off-by: George G. Davis <gdavis at mvista.com>
---
 arch/arm/cpu/arm1136/cpu.c   |    8 ++++----
 arch/arm/cpu/arm1136/start.S |    4 ++--
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/arm/cpu/arm1136/cpu.c b/arch/arm/cpu/arm1136/cpu.c
index ade7f46..a00698f 100644
--- a/arch/arm/cpu/arm1136/cpu.c
+++ b/arch/arm/cpu/arm1136/cpu.c
@@ -69,8 +69,8 @@ int cleanup_before_linux (void)
 
 static void cache_flush(void)
 {
-	unsigned long i = 0;
-
-	asm ("mcr p15, 0, %0, c7, c7, 0": :"r" (i));  /* invalidate both caches and flush btb */
-	asm ("mcr p15, 0, %0, c7, c10, 4": :"r" (i)); /* mem barrier to sync things */
+	asm (
+	"	mcr p15, 0, %0, c7, c14, 0	@ Clean & invalidate D-Cache\n"
+	"	mcr p15, 0, %0, c7, c10, 4	@ DSB\n"
+		: : "r" (0) : "memory");
 }
diff --git a/arch/arm/cpu/arm1136/start.S b/arch/arm/cpu/arm1136/start.S
index 957f438..922d01c 100644
--- a/arch/arm/cpu/arm1136/start.S
+++ b/arch/arm/cpu/arm1136/start.S
@@ -226,8 +226,8 @@ cpu_init_crit:
 	 * flush v4 I/D caches
 	 */
 	mov	r0, #0
-	mcr	p15, 0, r0, c7, c7, 0	/* flush v3/v4 cache */
-	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */
+	mcr	p15, 0, r0, c7, c7, 0	/* Invalidate I+D+BTB caches */
+	mcr	p15, 0, r0, c8, c7, 0	/* Invalidate Unified TLB */
 
 	/*
 	 * disable MMU stuff and caches
-- 
1.6.3.3.328.ga9ee94