diff options
| -rw-r--r-- | lib/sbi/sbi_fwft.c | 10 | ||||
| -rw-r--r-- | lib/sbi/sbi_hart.c | 18 |
2 files changed, 19 insertions, 9 deletions
diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c index 373140b7..574b875e 100644 --- a/lib/sbi/sbi_fwft.c +++ b/lib/sbi/sbi_fwft.c @@ -160,8 +160,16 @@ static int fwft_get_double_trap(struct fwft_config *conf, unsigned long *value) static int fwft_adue_supported(struct fwft_config *conf) { + /* + * FWFT.PTE_AD_HW_UPDATING is only supported when both Svade and Svadu + * are supported. We need both in order to support toggling and to + * ensure the reset value of zero is valid (it wouldn't be when only + * Svadu is supported). + */ if (!sbi_hart_has_extension(sbi_scratch_thishart_ptr(), - SBI_HART_EXT_SVADU)) + SBI_HART_EXT_SVADU) || + !sbi_hart_has_extension(sbi_scratch_thishart_ptr(), + SBI_HART_EXT_SVADE)) return SBI_ENOTSUPP; return SBI_OK; diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c index 92c602aa..43197721 100644 --- a/lib/sbi/sbi_hart.c +++ b/lib/sbi/sbi_hart.c @@ -137,6 +137,9 @@ static void mstatus_init(struct sbi_scratch *scratch) if (sbi_hart_priv_version(scratch) >= SBI_HART_PRIV_VER_1_12) { menvcfg_val = csr_read64(CSR_MENVCFG); + /* Disable HW A/D updating by default */ + menvcfg_val &= ~ENVCFG_ADUE; + /* Disable double trap by default */ menvcfg_val &= ~ENVCFG_DTE; @@ -158,18 +161,17 @@ static void mstatus_init(struct sbi_scratch *scratch) #endif __set_menvcfg_ext(SBI_HART_EXT_SSTC, ENVCFG_STCE) __set_menvcfg_ext(SBI_HART_EXT_SMCDELEG, ENVCFG_CDE); - __set_menvcfg_ext(SBI_HART_EXT_SVADU, ENVCFG_ADUE); - -#undef __set_menvcfg_ext /* - * When both Svade and Svadu are present in DT, the default scheme for managing - * the PTE A/D bits should use Svade. Check Svadu before Svade extension to ensure - * that the ADUE bit is cleared when the Svade support are specified. + * Assume only Svadu is supported when it is the only extension + * present in the ISA string. Svade is assumed when neither are + * present. When both are present we must default to Svade (see + * the zero reset value of FWFT.PTE_AD_HW_UPDATING). */ + if (!sbi_hart_has_extension(scratch, SBI_HART_EXT_SVADE)) + __set_menvcfg_ext(SBI_HART_EXT_SVADU, ENVCFG_ADUE); - if (sbi_hart_has_extension(scratch, SBI_HART_EXT_SVADE)) - menvcfg_val &= ~ENVCFG_ADUE; +#undef __set_menvcfg_ext csr_write64(CSR_MENVCFG, menvcfg_val); |