diff options
Diffstat (limited to 'arch/riscv/errata/thead/errata.c')
| -rw-r--r-- | arch/riscv/errata/thead/errata.c | 57 |
1 files changed, 47 insertions, 10 deletions
diff --git a/arch/riscv/errata/thead/errata.c b/arch/riscv/errata/thead/errata.c index b1c410bbc1ae..0b942183f708 100644 --- a/arch/riscv/errata/thead/errata.c +++ b/arch/riscv/errata/thead/errata.c @@ -10,29 +10,37 @@ #include <linux/string.h> #include <linux/uaccess.h> #include <asm/alternative.h> +#include <asm/bugs.h> #include <asm/cacheflush.h> #include <asm/cpufeature.h> #include <asm/dma-noncoherent.h> #include <asm/errata_list.h> #include <asm/hwprobe.h> #include <asm/io.h> -#include <asm/patch.h> +#include <asm/text-patching.h> #include <asm/vendorid_list.h> +#include <asm/vendor_extensions.h> -static bool errata_probe_pbmt(unsigned int stage, - unsigned long arch_id, unsigned long impid) +#define CSR_TH_SXSTATUS 0x5c0 +#define SXSTATUS_MAEE _AC(0x200000, UL) + +static bool errata_probe_mae(unsigned int stage, + unsigned long arch_id, unsigned long impid) { - if (!IS_ENABLED(CONFIG_ERRATA_THEAD_PBMT)) + if (!IS_ENABLED(CONFIG_ERRATA_THEAD_MAE)) return false; if (arch_id != 0 || impid != 0) return false; - if (stage == RISCV_ALTERNATIVES_EARLY_BOOT || - stage == RISCV_ALTERNATIVES_MODULE) - return true; + if (stage != RISCV_ALTERNATIVES_EARLY_BOOT && + stage != RISCV_ALTERNATIVES_MODULE) + return false; + + if (!(csr_read(CSR_TH_SXSTATUS) & SXSTATUS_MAEE)) + return false; - return false; + return true; } /* @@ -135,19 +143,46 @@ static bool errata_probe_pmu(unsigned int stage, return true; } +static bool errata_probe_ghostwrite(unsigned int stage, + unsigned long arch_id, unsigned long impid) +{ + if (!IS_ENABLED(CONFIG_ERRATA_THEAD_GHOSTWRITE)) + return false; + + /* + * target-c9xx cores report arch_id and impid as 0 + * + * While ghostwrite may not affect all c9xx cores that implement + * xtheadvector, there is no futher granularity than c9xx. Assume + * vulnerable for this entire class of processors when xtheadvector is + * enabled. + */ + if (arch_id != 0 || impid != 0) + return false; + + if (stage != RISCV_ALTERNATIVES_EARLY_BOOT) + return false; + + ghostwrite_set_vulnerable(); + + return true; +} + static u32 thead_errata_probe(unsigned int stage, unsigned long archid, unsigned long impid) { u32 cpu_req_errata = 0; - if (errata_probe_pbmt(stage, archid, impid)) - cpu_req_errata |= BIT(ERRATA_THEAD_PBMT); + if (errata_probe_mae(stage, archid, impid)) + cpu_req_errata |= BIT(ERRATA_THEAD_MAE); errata_probe_cmo(stage, archid, impid); if (errata_probe_pmu(stage, archid, impid)) cpu_req_errata |= BIT(ERRATA_THEAD_PMU); + errata_probe_ghostwrite(stage, archid, impid); + return cpu_req_errata; } @@ -160,6 +195,8 @@ void thead_errata_patch_func(struct alt_entry *begin, struct alt_entry *end, u32 tmp; void *oldptr, *altptr; + BUILD_BUG_ON(ERRATA_THEAD_NUMBER >= RISCV_VENDOR_EXT_ALTERNATIVES_BASE); + for (alt = begin; alt < end; alt++) { if (alt->vendor_id != THEAD_VENDOR_ID) continue; |