arm64: Avoid Cavium TX2 erratum 219 when switching TTBR

As a PRFM instruction racing against a TTBR update can have undesirable
effects on TX2, NOP-out such PRFM on cores that are affected by
the TX2-219 erratum.

Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Marc Zyngier 2019-04-09 16:22:24 +01:00 committed by Will Deacon
parent 93916beb70
commit 9405447ef7
3 changed files with 9 additions and 1 deletions

View File

@ -53,7 +53,8 @@
#define ARM64_HAS_DCPODP 43
#define ARM64_WORKAROUND_1463225 44
#define ARM64_WORKAROUND_CAVIUM_TX2_219_TVM 45
#define ARM64_WORKAROUND_CAVIUM_TX2_219_PRFM 46
#define ARM64_NCAPS 46
#define ARM64_NCAPS 47
#endif /* __ASM_CPUCAPS_H */

View File

@ -884,6 +884,11 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
ERRATA_MIDR_RANGE_LIST(tx2_family_cpus),
.matches = needs_tx2_tvm_workaround,
},
{
.desc = "Cavium ThunderX2 erratum 219 (PRFM removal)",
.capability = ARM64_WORKAROUND_CAVIUM_TX2_219_PRFM,
ERRATA_MIDR_RANGE_LIST(tx2_family_cpus),
},
#endif
{
}

View File

@ -1070,7 +1070,9 @@ alternative_insn isb, nop, ARM64_WORKAROUND_QCOM_FALKOR_E1003
#else
ldr x30, =vectors
#endif
alternative_if_not ARM64_WORKAROUND_CAVIUM_TX2_219_PRFM
prfm plil1strm, [x30, #(1b - tramp_vectors)]
alternative_else_nop_endif
msr vbar_el1, x30
add x30, x30, #(1b - tramp_vectors)
isb