arm64: Add workaround for Cortex-A76 erratum 1286807
On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual address
for a cacheable mapping of a location is being accessed by a core while
another core is remapping the virtual address to a new physical page
using the recommended break-before-make sequence, then under very rare
circumstances TLBI+DSB completes before a read using the translation
being invalidated has been observed by other observers. The workaround
repeats the TLBI+DSB operation and is shared with the Qualcomm Falkor
erratum 1009
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 787d785..ea2ab03 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -497,6 +497,24 @@
If unsure, say Y.
+config ARM64_ERRATUM_1286807
+ bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
+ default y
+ select ARM64_WORKAROUND_REPEAT_TLBI
+ help
+ This option adds workaround for ARM Cortex-A76 erratum 1286807
+
+ On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
+ address for a cacheable mapping of a location is being
+ accessed by a core while another core is remapping the virtual
+ address to a new physical page using the recommended
+ break-before-make sequence, then under very rare circumstances
+ TLBI+DSB completes before a read using the translation being
+ invalidated has been observed by other observers. The
+ workaround repeats the TLBI+DSB operation.
+
+ If unsure, say Y.
+
config CAVIUM_ERRATUM_22375
bool "Cavium erratum 22375, 24313"
default y
@@ -566,9 +584,16 @@
is unchanged. Work around the erratum by invalidating the walk cache
entries for the trampoline before entering the kernel proper.
+config ARM64_WORKAROUND_REPEAT_TLBI
+ bool
+ help
+ Enable the repeat TLBI workaround for Falkor erratum 1009 and
+ Cortex-A76 erratum 1286807.
+
config QCOM_FALKOR_ERRATUM_1009
bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
default y
+ select ARM64_WORKAROUND_REPEAT_TLBI
help
On Falkor v1, the CPU may prematurely complete a DSB following a
TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h
index c3c0387..5dfd238 100644
--- a/arch/arm64/include/asm/tlbflush.h
+++ b/arch/arm64/include/asm/tlbflush.h
@@ -41,14 +41,14 @@
ALTERNATIVE("nop\n nop", \
"dsb ish\n tlbi " #op, \
ARM64_WORKAROUND_REPEAT_TLBI, \
- CONFIG_QCOM_FALKOR_ERRATUM_1009) \
+ CONFIG_ARM64_WORKAROUND_REPEAT_TLBI) \
: : )
#define __TLBI_1(op, arg) asm ("tlbi " #op ", %0\n" \
ALTERNATIVE("nop\n nop", \
"dsb ish\n tlbi " #op ", %0", \
ARM64_WORKAROUND_REPEAT_TLBI, \
- CONFIG_QCOM_FALKOR_ERRATUM_1009) \
+ CONFIG_ARM64_WORKAROUND_REPEAT_TLBI) \
: : "r" (arg))
#define __TLBI_N(op, arg, n, ...) __TLBI_##n(op, arg)
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index a509e351..6ad715d 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -570,6 +570,20 @@ static const struct midr_range arm64_harden_el2_vectors[] = {
#endif
+#ifdef CONFIG_ARM64_WORKAROUND_REPEAT_TLBI
+
+static const struct midr_range arm64_repeat_tlbi_cpus[] = {
+#ifdef CONFIG_QCOM_FALKOR_ERRATUM_1009
+ MIDR_RANGE(MIDR_QCOM_FALKOR_V1, 0, 0, 0, 0),
+#endif
+#ifdef CONFIG_ARM64_ERRATUM_1286807
+ MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 3, 0),
+#endif
+ {},
+};
+
+#endif
+
const struct arm64_cpu_capabilities arm64_errata[] = {
#if defined(CONFIG_ARM64_ERRATUM_826319) || \
defined(CONFIG_ARM64_ERRATUM_827319) || \
@@ -695,11 +709,11 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
.matches = is_kryo_midr,
},
#endif
-#ifdef CONFIG_QCOM_FALKOR_ERRATUM_1009
+#ifdef CONFIG_ARM64_WORKAROUND_REPEAT_TLBI
{
- .desc = "Qualcomm Technologies Falkor erratum 1009",
+ .desc = "Qualcomm erratum 1009, ARM erratum 1286807",
.capability = ARM64_WORKAROUND_REPEAT_TLBI,
- ERRATA_MIDR_REV(MIDR_QCOM_FALKOR_V1, 0, 0),
+ ERRATA_MIDR_RANGE_LIST(arm64_repeat_tlbi_cpus),
},
#endif
#ifdef CONFIG_ARM64_ERRATUM_858921
