arm64: errata: add detection for AMEVCNTR01 incrementing incorrectly

[linux-stable] / arch / arm64 / Kconfig

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 42f135e2176b4e10436e5f4d46353650c628b18a..24cce3b9ff1a700598a436a73f02176f3ce8b9e0 100644 (file)
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -683,6 +683,23 @@ config ARM64_ERRATUM_2441009
 
          If unsure, say Y.
 
+config ARM64_ERRATUM_2457168
+       bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
+       depends on ARM64_AMU_EXTN
+       default y
+       help
+         This option adds the workaround for ARM Cortex-A510 erratum 2457168.
+
+         The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
+         as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
+         incorrectly giving a significantly higher output value.
+
+         Work around this problem by returning 0 when reading the affected counter in
+         key locations that results in disabling all users of this counter. This effect
+         is the same to firmware disabling affected counters.
+
+         If unsure, say Y.
+
 config CAVIUM_ERRATUM_22375
        bool "Cavium erratum 22375, 24313"
        default y