diff options
| -rw-r--r-- | Documentation/arch/arm64/silicon-errata.rst | 2 | ||||
| -rw-r--r-- | drivers/resctrl/mpam_devices.c | 55 | ||||
| -rw-r--r-- | drivers/resctrl/mpam_internal.h | 1 |
3 files changed, 55 insertions, 3 deletions
diff --git a/Documentation/arch/arm64/silicon-errata.rst b/Documentation/arch/arm64/silicon-errata.rst index a65620f98e3a..a4b246655e37 100644 --- a/Documentation/arch/arm64/silicon-errata.rst +++ b/Documentation/arch/arm64/silicon-errata.rst @@ -249,6 +249,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | NVIDIA | T241 MPAM | T241-MPAM-1 | N/A | +----------------+-----------------+-----------------+-----------------------------+ +| NVIDIA | T241 MPAM | T241-MPAM-4 | N/A | ++----------------+-----------------+-----------------+-----------------------------+ +----------------+-----------------+-----------------+-----------------------------+ | Freescale/NXP | LS2080A/LS1043A | A-008585 | FSL_ERRATUM_A008585 | +----------------+-----------------+-----------------+-----------------------------+ diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c index b1fe6f171b68..142e7ea960e5 100644 --- a/drivers/resctrl/mpam_devices.c +++ b/drivers/resctrl/mpam_devices.c @@ -679,6 +679,12 @@ static const struct mpam_quirk mpam_quirks[] = { .iidr_mask = MPAM_IIDR_MATCH_ONE, .workaround = T241_SCRUB_SHADOW_REGS, }, + { + /* NVIDIA t241 erratum T241-MPAM-4 */ + .iidr = MPAM_IIDR_NVIDIA_T241, + .iidr_mask = MPAM_IIDR_MATCH_ONE, + .workaround = T241_FORCE_MBW_MIN_TO_ONE, + }, { NULL } /* Sentinel */ }; @@ -1464,6 +1470,37 @@ static void mpam_quirk_post_config_change(struct mpam_msc_ris *ris, u16 partid, mpam_apply_t241_erratum(ris, partid); } +static u16 mpam_wa_t241_force_mbw_min_to_one(struct mpam_props *props) +{ + u16 max_hw_value, min_hw_granule, res0_bits; + + res0_bits = 16 - props->bwa_wd; + max_hw_value = ((1 << props->bwa_wd) - 1) << res0_bits; + min_hw_granule = ~max_hw_value; + + return min_hw_granule + 1; +} + +static u16 mpam_wa_t241_calc_min_from_max(struct mpam_props *props, + struct mpam_config *cfg) +{ + u16 val = 0; + u16 max; + u16 delta = ((5 * MPAMCFG_MBW_MAX_MAX) / 100) - 1; + + if (mpam_has_feature(mpam_feat_mbw_max, cfg)) { + max = cfg->mbw_max; + } else { + /* Resetting. Hence, use the ris specific default. */ + max = GENMASK(15, 16 - props->bwa_wd); + } + + if (max > delta) + val = max - delta; + + return val; +} + /* Called via IPI. Call while holding an SRCU reference */ static void mpam_reprogram_ris_partid(struct mpam_msc_ris *ris, u16 partid, struct mpam_config *cfg) @@ -1504,9 +1541,18 @@ static void mpam_reprogram_ris_partid(struct mpam_msc_ris *ris, u16 partid, mpam_write_partsel_reg(msc, MBW_PBM, cfg->mbw_pbm); } - if (mpam_has_feature(mpam_feat_mbw_min, rprops) && - mpam_has_feature(mpam_feat_mbw_min, cfg)) - mpam_write_partsel_reg(msc, MBW_MIN, 0); + if (mpam_has_feature(mpam_feat_mbw_min, rprops)) { + u16 val = 0; + + if (mpam_has_quirk(T241_FORCE_MBW_MIN_TO_ONE, msc)) { + u16 min = mpam_wa_t241_force_mbw_min_to_one(rprops); + + val = mpam_wa_t241_calc_min_from_max(rprops, cfg); + val = max(val, min); + } + + mpam_write_partsel_reg(msc, MBW_MIN, val); + } if (mpam_has_feature(mpam_feat_mbw_max, rprops)) { if (mpam_has_feature(mpam_feat_mbw_max, cfg)) @@ -2288,6 +2334,9 @@ static void mpam_enable_merge_class_features(struct mpam_component *comp) list_for_each_entry(vmsc, &comp->vmsc, comp_list) __class_props_mismatch(class, vmsc); + + if (mpam_has_quirk(T241_FORCE_MBW_MIN_TO_ONE, class)) + mpam_clear_feature(mpam_feat_mbw_min, &class->props); } /* diff --git a/drivers/resctrl/mpam_internal.h b/drivers/resctrl/mpam_internal.h index d9eb342ba222..f1adbdad3969 100644 --- a/drivers/resctrl/mpam_internal.h +++ b/drivers/resctrl/mpam_internal.h @@ -224,6 +224,7 @@ struct mpam_props { /* Workaround bits for msc->quirks */ enum mpam_device_quirks { T241_SCRUB_SHADOW_REGS, + T241_FORCE_MBW_MIN_TO_ONE, MPAM_QUIRK_LAST }; |