From 104a0c02e8b1936c049e18a6d4e4ab040fb61213 Mon Sep 17 00:00:00 2001 From: Andrew Pinski Date: Wed, 24 Feb 2016 17:44:57 -0800 Subject: [PATCH] arm64: Add workaround for Cavium erratum 27456 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI instructions may cause the icache to become corrupted if it contains data for a non-current ASID. This patch implements the workaround (which invalidates the local icache when switching the mm) by using code patching. Signed-off-by: Andrew Pinski Signed-off-by: David Daney Reviewed-by: Will Deacon Signed-off-by: Catalin Marinas --- Documentation/arm64/silicon-errata.txt | 1 + arch/arm64/Kconfig | 11 +++++++++++ arch/arm64/include/asm/cpufeature.h | 3 ++- arch/arm64/kernel/cpu_errata.c | 9 +++++++++ arch/arm64/mm/proc.S | 12 ++++++++++++ 5 files changed, 35 insertions(+), 1 deletion(-) diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt index 58b71ddf9b60..ba4b6acfc545 100644 --- a/Documentation/arm64/silicon-errata.txt +++ b/Documentation/arm64/silicon-errata.txt @@ -56,3 +56,4 @@ stable kernels. | | | | | | Cavium | ThunderX ITS | #22375, #24313 | CAVIUM_ERRATUM_22375 | | Cavium | ThunderX GICv3 | #23154 | CAVIUM_ERRATUM_23154 | +| Cavium | ThunderX Core | #27456 | CAVIUM_ERRATUM_27456 | diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index b6460911dd92..97cd2b9dafd4 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -435,6 +435,17 @@ config CAVIUM_ERRATUM_23154 If unsure, say Y. +config CAVIUM_ERRATUM_27456 + bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption" + default y + help + On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI + instructions may cause the icache to become corrupted if it + contains data for a non-current ASID. The fix is to + invalidate the icache when changing the mm context. + + If unsure, say Y. + endmenu diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index be88aef01f3d..1497163213ed 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -33,8 +33,9 @@ #define ARM64_HAS_NO_HW_PREFETCH 8 #define ARM64_HAS_UAO 9 #define ARM64_ALT_PAN_NOT_UAO 10 +#define ARM64_WORKAROUND_CAVIUM_27456 12 -#define ARM64_NCAPS 11 +#define ARM64_NCAPS 13 #ifndef __ASSEMBLY__ diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index e6bc988e8dbf..06afd04e02c0 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -87,6 +87,15 @@ const struct arm64_cpu_capabilities arm64_errata[] = { .capability = ARM64_WORKAROUND_CAVIUM_23154, MIDR_RANGE(MIDR_THUNDERX, 0x00, 0x01), }, +#endif +#ifdef CONFIG_CAVIUM_ERRATUM_27456 + { + /* Cavium ThunderX, T88 pass 1.x - 2.1 */ + .desc = "Cavium erratum 27456", + .capability = ARM64_WORKAROUND_CAVIUM_27456, + MIDR_RANGE(MIDR_THUNDERX, 0x00, + (1 << MIDR_VARIANT_SHIFT) | 1), + }, #endif { } diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 0c19534a901e..543f5198005a 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -25,6 +25,8 @@ #include #include #include +#include +#include #include "proc-macros.S" @@ -137,7 +139,17 @@ ENTRY(cpu_do_switch_mm) bfi x0, x1, #48, #16 // set the ASID msr ttbr0_el1, x0 // set TTBR0 isb +alternative_if_not ARM64_WORKAROUND_CAVIUM_27456 ret + nop + nop + nop +alternative_else + ic iallu + dsb nsh + isb + ret +alternative_endif ENDPROC(cpu_do_switch_mm) .pushsection ".idmap.text", "ax" -- 2.20.1