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authorWill Deacon <will.deacon@arm.com>2011-09-15 10:45:15 (GMT)
committerRussell King <rmk+kernel@arm.linux.org.uk>2011-09-17 11:47:17 (GMT)
commitf630c1bdfbf8fe423325beaf60027cfc7fd7c610 (patch)
tree9091179ae505fcb5aff937315c4f9c96602cba9a /arch/arm/kernel/smp_scu.c
parent279b1e0fd90ef63c7acb34a5ca573f065a6fefb4 (diff)
downloadlinux-fsl-qoriq-f630c1bdfbf8fe423325beaf60027cfc7fd7c610.tar.xz
ARM: 7091/1: errata: D-cache line maintenance operation by MVA may not succeed
This patch implements a workaround for erratum 764369 affecting Cortex-A9 MPCore with two or more processors (all current revisions). Under certain timing circumstances, a data cache line maintenance operation by MVA targeting an Inner Shareable memory region may fail to proceed up to either the Point of Coherency or to the Point of Unification of the system. This workaround adds a DSB instruction before the relevant cache maintenance functions and sets a specific bit in the diagnostic control register of the SCU. Cc: <stable@kernel.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/kernel/smp_scu.c')
-rw-r--r--arch/arm/kernel/smp_scu.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/arm/kernel/smp_scu.c b/arch/arm/kernel/smp_scu.c
index 79ed5e7..7fcddb7 100644
--- a/arch/arm/kernel/smp_scu.c
+++ b/arch/arm/kernel/smp_scu.c
@@ -13,6 +13,7 @@
#include <asm/smp_scu.h>
#include <asm/cacheflush.h>
+#include <asm/cputype.h>
#define SCU_CTRL 0x00
#define SCU_CONFIG 0x04
@@ -37,6 +38,15 @@ void __init scu_enable(void __iomem *scu_base)
{
u32 scu_ctrl;
+#ifdef CONFIG_ARM_ERRATA_764369
+ /* Cortex-A9 only */
+ if ((read_cpuid(CPUID_ID) & 0xff0ffff0) == 0x410fc090) {
+ scu_ctrl = __raw_readl(scu_base + 0x30);
+ if (!(scu_ctrl & 1))
+ __raw_writel(scu_ctrl | 0x1, scu_base + 0x30);
+ }
+#endif
+
scu_ctrl = __raw_readl(scu_base + SCU_CTRL);
/* already enabled? */
if (scu_ctrl & 1)