diff options
Diffstat (limited to 'arch/arm64/Kconfig')
| -rw-r--r-- | arch/arm64/Kconfig | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index a6002084f09c..50f6ddc7e3a0 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -407,6 +407,25 @@ menu "Kernel Features" menu "ARM errata workarounds via the alternatives framework" +config AMPERE_ERRATUM_AC03_CPU_38 + bool "AmpereOne: AC03_CPU_38: Certain bits in the Virtualization Translation Control Register and Translation Control Registers do not follow RES0 semantics" + default y + help + This option adds an alternative code sequence to work around Ampere + erratum AC03_CPU_38 on AmpereOne. + + The affected design reports FEAT_HAFDBS as not implemented in + ID_AA64MMFR1_EL1.HAFDBS, but (V)TCR_ELx.{HA,HD} are not RES0 + as required by the architecture. The unadvertised HAFDBS + implementation suffers from an additional erratum where hardware + A/D updates can occur after a PTE has been marked invalid. + + The workaround forces KVM to explicitly set VTCR_EL2.HA to 0, + which avoids enabling unadvertised hardware Access Flag management + at stage-2. + + If unsure, say Y. + config ARM64_WORKAROUND_CLEAN_CACHE bool |