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>
diff --git a/arch/arm/mm/cache-v7.S b/arch/arm/mm/cache-v7.S
index 3b24bfa..07c4bc8 100644
--- a/arch/arm/mm/cache-v7.S
+++ b/arch/arm/mm/cache-v7.S
@@ -174,6 +174,10 @@
dcache_line_size r2, r3
sub r3, r2, #1
bic r12, r0, r3
+#ifdef CONFIG_ARM_ERRATA_764369
+ ALT_SMP(W(dsb))
+ ALT_UP(W(nop))
+#endif
1:
USER( mcr p15, 0, r12, c7, c11, 1 ) @ clean D line to the point of unification
add r12, r12, r2
@@ -223,6 +227,10 @@
add r1, r0, r1
sub r3, r2, #1
bic r0, r0, r3
+#ifdef CONFIG_ARM_ERRATA_764369
+ ALT_SMP(W(dsb))
+ ALT_UP(W(nop))
+#endif
1:
mcr p15, 0, r0, c7, c14, 1 @ clean & invalidate D line / unified line
add r0, r0, r2
@@ -247,6 +255,10 @@
sub r3, r2, #1
tst r0, r3
bic r0, r0, r3
+#ifdef CONFIG_ARM_ERRATA_764369
+ ALT_SMP(W(dsb))
+ ALT_UP(W(nop))
+#endif
mcrne p15, 0, r0, c7, c14, 1 @ clean & invalidate D / U line
tst r1, r3
@@ -270,6 +282,10 @@
dcache_line_size r2, r3
sub r3, r2, #1
bic r0, r0, r3
+#ifdef CONFIG_ARM_ERRATA_764369
+ ALT_SMP(W(dsb))
+ ALT_UP(W(nop))
+#endif
1:
mcr p15, 0, r0, c7, c10, 1 @ clean D / U line
add r0, r0, r2
@@ -288,6 +304,10 @@
dcache_line_size r2, r3
sub r3, r2, #1
bic r0, r0, r3
+#ifdef CONFIG_ARM_ERRATA_764369
+ ALT_SMP(W(dsb))
+ ALT_UP(W(nop))
+#endif
1:
mcr p15, 0, r0, c7, c14, 1 @ clean & invalidate D / U line
add r0, r0, r2