From ce8c80c536dac9f325a051b30bf7730ee505eddc Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Mon, 19 Nov 2018 11:27:28 +0000 Subject: [PATCH] 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 Signed-off-by: Catalin Marinas --- Documentation/arm64/silicon-errata.txt | 1 + arch/arm64/Kconfig | 25 +++++++++++++++++++++++++ arch/arm64/include/asm/tlbflush.h | 4 ++-- arch/arm64/kernel/cpu_errata.c | 20 +++++++++++++++++--- 4 files changed, 45 insertions(+), 5 deletions(-) diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt index 76ccded8b74c..8f9577621144 100644 --- a/Documentation/arm64/silicon-errata.txt +++ b/Documentation/arm64/silicon-errata.txt @@ -57,6 +57,7 @@ stable kernels. | ARM | Cortex-A73 | #858921 | ARM64_ERRATUM_858921 | | ARM | Cortex-A55 | #1024718 | ARM64_ERRATUM_1024718 | | ARM | Cortex-A76 | #1188873 | ARM64_ERRATUM_1188873 | +| ARM | Cortex-A76 | #1286807 | ARM64_ERRATUM_1286807 | | ARM | MMU-500 | #841119,#826419 | N/A | | | | | | | Cavium | ThunderX ITS | #22375, #24313 | CAVIUM_ERRATUM_22375 | diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 787d7850e064..ea2ab0330e3a 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -497,6 +497,24 @@ config ARM64_ERRATUM_1188873 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 @@ config QCOM_FALKOR_ERRATUM_1003 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 c3c0387aee18..5dfd23897dea 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 a509e35132d2..6ad715d67df8 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