diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 166efa2a19cd96eb05ad5b4b599708c9a68c1d70..ec0f6589af05e3ae4b838e5361e22c5a4ef81ae7 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1202,6 +1202,17 @@ config ARM_ERRATA_753970 This has the same effect as the cache sync operation: store buffer drain and waiting for all buffers empty. +config ARM_ERRATA_754322 + bool "ARM errata: possible faulty MMU translations following an ASID switch" + depends on CPU_V7 + help + This option enables the workaround for the 754322 Cortex-A9 (r2p*, + r3p*) erratum. A speculative memory access may cause a page table walk + which starts prior to an ASID switch but completes afterwards. This + can populate the micro-TLB with a stale entry which may be hit with + the new ASID. This workaround places two dsb instructions in the mm + switching code so that no page table walks can cross the ASID switch. + endmenu source "arch/arm/common/Kconfig" diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index 8e3356239136a2423095b24b466858100b00c31d..f7498f1a2e86865a5c648dc8c85ed74d15decd3c 100644 --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -107,11 +107,17 @@ ENTRY(cpu_v7_switch_mm) ALT_UP(orr r0, r0, #TTB_FLAGS_UP) #ifdef CONFIG_ARM_ERRATA_430973 mcr p15, 0, r2, c7, c5, 6 @ flush BTAC/BTB +#endif +#ifdef CONFIG_ARM_ERRATA_754322 + dsb #endif mcr p15, 0, r2, c13, c0, 1 @ set reserved context ID isb 1: mcr p15, 0, r0, c2, c0, 0 @ set TTB 0 isb +#ifdef CONFIG_ARM_ERRATA_754322 + dsb +#endif mcr p15, 0, r1, c13, c0, 1 @ set context ID isb #endif