On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory accesses may cause undefined fault (Data abort, DFSC=0b111111) due to the CPU Errata (Fujitsu #010001).
This patch introduces the workaround to the problem. The workaround is to change the fault handler for Data abort DFSC=0b111111 to ignore this undefined fault, which will only affect the Fujitsu-A64FX. Signed-off-by: Lei Zhang <zhang....@jp.fujitsu.com> Tested-by: Lei Zhang <zhang....@jp.fujitsu.com> --- Documentation/arm64/silicon-errata.txt | 1 + arch/arm64/Kconfig | 13 +++++++++++++ arch/arm64/include/asm/cpucaps.h | 3 ++- arch/arm64/include/asm/cputype.h | 4 ++++ arch/arm64/kernel/cpu_errata.c | 8 ++++++++ arch/arm64/mm/fault.c | 24 +++++++++++++++++++++++- 6 files changed, 51 insertions(+), 2 deletions(-) diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt index 1f09d04..26d64e9 100644 --- a/Documentation/arm64/silicon-errata.txt +++ b/Documentation/arm64/silicon-errata.txt @@ -80,3 +80,4 @@ stable kernels. | Qualcomm Tech. | Falkor v1 | E1009 | QCOM_FALKOR_ERRATUM_1009 | | Qualcomm Tech. | QDF2400 ITS | E0065 | QCOM_QDF2400_ERRATUM_0065 | | Qualcomm Tech. | Falkor v{1,2} | E1041 | QCOM_FALKOR_ERRATUM_1041 | +| Fujitsu | A64FX | E#010001 | FUJITSU_ERRATUM_010001 | diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index a4168d3..9c09b2b 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -643,6 +643,19 @@ config QCOM_FALKOR_ERRATUM_E1041 If unsure, say Y. +config FUJITSU_ERRATUM_010001 + bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly" + default y + help + This option adds workaround for Fujitsu-A64FX erratum E#010001. + On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory accesses + may cause undefined fault (Data abort, DFSC=0b111111). + The workaround is to replace the fault handler for Data abort DFSC=0b111111 + with a new one to ignore this undefined fault, which will only affect + the Fujitsu-A64FX. + + If unsure, say Y. + endmenu diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h index 82e9099..3a0b375 100644 --- a/arch/arm64/include/asm/cpucaps.h +++ b/arch/arm64/include/asm/cpucaps.h @@ -60,7 +60,8 @@ #define ARM64_HAS_ADDRESS_AUTH_IMP_DEF 39 #define ARM64_HAS_GENERIC_AUTH_ARCH 40 #define ARM64_HAS_GENERIC_AUTH_IMP_DEF 41 +#define ARM64_WORKAROUND_FUJITSU_A64FX_0100001 42 -#define ARM64_NCAPS 42 +#define ARM64_NCAPS 43 #endif /* __ASM_CPUCAPS_H */ diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h index 951ed1a..70203f9 100644 --- a/arch/arm64/include/asm/cputype.h +++ b/arch/arm64/include/asm/cputype.h @@ -76,6 +76,7 @@ #define ARM_CPU_IMP_BRCM 0x42 #define ARM_CPU_IMP_QCOM 0x51 #define ARM_CPU_IMP_NVIDIA 0x4E +#define ARM_CPU_IMP_FUJITSU 0x46 #define ARM_CPU_PART_AEM_V8 0xD0F #define ARM_CPU_PART_FOUNDATION 0xD00 @@ -104,6 +105,8 @@ #define NVIDIA_CPU_PART_DENVER 0x003 #define NVIDIA_CPU_PART_CARMEL 0x004 +#define FUJITSU_CPU_PART_A64FX 0x001 + #define MIDR_CORTEX_A53 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A53) #define MIDR_CORTEX_A57 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A57) #define MIDR_CORTEX_A72 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A72) @@ -122,6 +125,7 @@ #define MIDR_QCOM_KRYO MIDR_CPU_MODEL(ARM_CPU_IMP_QCOM, QCOM_CPU_PART_KRYO) #define MIDR_NVIDIA_DENVER MIDR_CPU_MODEL(ARM_CPU_IMP_NVIDIA, NVIDIA_CPU_PART_DENVER) #define MIDR_NVIDIA_CARMEL MIDR_CPU_MODEL(ARM_CPU_IMP_NVIDIA, NVIDIA_CPU_PART_CARMEL) +#define MIDR_FUJITSU_A64FX MIDR_CPU_MODEL(ARM_CPU_IMP_FUJITSU, FUJITSU_CPU_PART_A64FX) #ifndef __ASSEMBLY__ diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index 9950bb0..fc0737f 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -739,6 +739,14 @@ static bool has_ssbd_mitigation(const struct arm64_cpu_capabilities *entry, ERRATA_MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 2, 0), }, #endif +#ifdef CONFIG_FUJITSU_ERRATUM_010001 + { + .desc = "Fujitsu erratum 010001", + .capability = ARM64_WORKAROUND_FUJITSU_A64FX_0100001, + ERRATA_MIDR_RANGE(MIDR_FUJITSU_A64FX, 0, 0, 1, 0), + }, +#endif + { } }; diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index efb7b2c..37e4f18 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -666,6 +666,28 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs) return 0; } +static int do_bad_unknown_63(unsigned long addr, unsigned int esr, struct pt_regs *regs) +{ + /* + * On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), + * memory accesses may spuriously trigger data aborts with + * DFSC=0b111111. + */ + if (IS_ENABLED(CONFIG_FUJITSU_ERRATUM_010001)) { + if (cpus_have_cap(ARM64_WORKAROUND_FUJITSU_A64FX_0100001)) { + return 0; + } else { /* cpu capabilities maybe not ready*/ + unsigned int current_cpu_midr = read_cpuid_id(); + const struct midr_range fujitsu_a64fx_midr_range = { + MIDR_FUJITSU_A64FX, MIDR_CPU_VAR_REV(0, 0), MIDR_CPU_VAR_REV(1, 0) + }; + if (is_midr_in_range(current_cpu_midr, &fujitsu_a64fx_midr_range) == TRUE) + return 0; + } + } + return do_bad(addr, esr, regs); +} + static const struct fault_info fault_info[] = { { do_bad, SIGKILL, SI_KERNEL, "ttbr address size fault" }, { do_bad, SIGKILL, SI_KERNEL, "level 1 address size fault" }, @@ -730,7 +752,7 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs) { do_bad, SIGKILL, SI_KERNEL, "unknown 60" }, { do_bad, SIGKILL, SI_KERNEL, "section domain fault" }, { do_bad, SIGKILL, SI_KERNEL, "page domain fault" }, - { do_bad, SIGKILL, SI_KERNEL, "unknown 63" }, + { do_bad_unknown_63, SIGKILL, SI_KERNEL, "unknown 63" }, }; int handle_guest_sea(phys_addr_t addr, unsigned int esr) -- 1.8.3.1