[ARM] 5488/1: ARM errata: Invalidation of the Instruction Cache operation can fail
This patch implements the recommended workaround for erratum 411920
(ARM1136, ARM1156, ARM1176).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 99875dd..e28a76b 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -740,6 +740,15 @@
source "arch/arm/Kconfig-nommu"
endif
+config ARM_ERRATA_411920
+ bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
+ depends on CPU_V6 && !SMP
+ help
+ Invalidation of the Instruction Cache operation can
+ fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
+ It does not affect the MPCore. This option enables the ARM Ltd.
+ recommended workaround.
+
endmenu
source "arch/arm/common/Kconfig"
diff --git a/arch/arm/mm/cache-v6.S b/arch/arm/mm/cache-v6.S
index 2c6c2a7..8f5c13f 100644
--- a/arch/arm/mm/cache-v6.S
+++ b/arch/arm/mm/cache-v6.S
@@ -20,6 +20,31 @@
#define D_CACHE_LINE_SIZE 32
#define BTB_FLUSH_SIZE 8
+#ifdef CONFIG_ARM_ERRATA_411920
+/*
+ * Invalidate the entire I cache (this code is a workaround for the ARM1136
+ * erratum 411920 - Invalidate Instruction Cache operation can fail. This
+ * erratum is present in 1136, 1156 and 1176. It does not affect the MPCore.
+ *
+ * Registers:
+ * r0 - set to 0
+ * r1 - corrupted
+ */
+ENTRY(v6_icache_inval_all)
+ mov r0, #0
+ mrs r1, cpsr
+ cpsid ifa @ disable interrupts
+ mcr p15, 0, r0, c7, c5, 0 @ invalidate entire I-cache
+ mcr p15, 0, r0, c7, c5, 0 @ invalidate entire I-cache
+ mcr p15, 0, r0, c7, c5, 0 @ invalidate entire I-cache
+ mcr p15, 0, r0, c7, c5, 0 @ invalidate entire I-cache
+ msr cpsr_cx, r1 @ restore interrupts
+ .rept 11 @ ARM Ltd recommends at least
+ nop @ 11 NOPs
+ .endr
+ mov pc, lr
+#endif
+
/*
* v6_flush_cache_all()
*
@@ -31,8 +56,12 @@
mov r0, #0
#ifdef HARVARD_CACHE
mcr p15, 0, r0, c7, c14, 0 @ D cache clean+invalidate
+#ifndef CONFIG_ARM_ERRATA_411920
mcr p15, 0, r0, c7, c5, 0 @ I+BTB cache invalidate
#else
+ b v6_icache_inval_all
+#endif
+#else
mcr p15, 0, r0, c7, c15, 0 @ Cache clean+invalidate
#endif
mov pc, lr
@@ -103,8 +132,12 @@
mov r0, #0
#ifdef HARVARD_CACHE
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
+#ifndef CONFIG_ARM_ERRATA_411920
mcr p15, 0, r0, c7, c5, 0 @ I+BTB cache invalidate
#else
+ b v6_icache_inval_all
+#endif
+#else
mcr p15, 0, r0, c7, c5, 6 @ invalidate BTB
#endif
mov pc, lr
diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index 4e28348..c07222e 100644
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -18,6 +18,10 @@
#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
@@ -32,10 +36,15 @@
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
:
: "r" (to), "r" (to + PAGE_SIZE - L1_CACHE_BYTES), "r" (zero)
: "cc");
+#ifdef CONFIG_ARM_ERRATA_411920
+ v6_icache_inval_all();
+#endif
}
void flush_cache_mm(struct mm_struct *mm)
@@ -48,11 +57,16 @@
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"
- " mcr p15, 0, %0, c7, c10, 4"
+#endif
:
: "r" (0)
: "cc");
+#ifdef CONFIG_ARM_ERRATA_411920
+ v6_icache_inval_all();
+#endif
}
}
@@ -67,11 +81,16 @@
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"
- " mcr p15, 0, %0, c7, c10, 4"
+#endif
:
: "r" (0)
: "cc");
+#ifdef CONFIG_ARM_ERRATA_411920
+ v6_icache_inval_all();
+#endif
}
}