The SMMU can support up to 20 bits of SSID. Add a second level of page tables to accommodate this. Devices that support more than 1024 SSIDs now have a table of 1024 L1 entries (8kB), pointing to tables of 1024 context descriptors (64kB), allocated on demand.
Tested-by: Zhangfei Gao <[email protected]> Reviewed-by: Jonathan Cameron <[email protected]> Signed-off-by: Jean-Philippe Brucker <[email protected]> --- drivers/iommu/arm-smmu-v3.c | 154 +++++++++++++++++++++++++++++++++--- 1 file changed, 144 insertions(+), 10 deletions(-) diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index b825a5639afc..bf106a7b53eb 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -224,6 +224,7 @@ #define STRTAB_STE_0_S1FMT GENMASK_ULL(5, 4) #define STRTAB_STE_0_S1FMT_LINEAR 0 +#define STRTAB_STE_0_S1FMT_64K_L2 2 #define STRTAB_STE_0_S1CTXPTR_MASK GENMASK_ULL(51, 6) #define STRTAB_STE_0_S1CDMAX GENMASK_ULL(63, 59) @@ -263,7 +264,20 @@ #define STRTAB_STE_3_S2TTB_MASK GENMASK_ULL(51, 4) -/* Context descriptor (stage-1 only) */ +/* + * Context descriptors. + * + * Linear: when less than 1024 SSIDs are supported + * 2lvl: at most 1024 L1 entries, + * 1024 lazy entries per table. + */ +#define CTXDESC_SPLIT 10 +#define CTXDESC_L2_ENTRIES (1 << CTXDESC_SPLIT) + +#define CTXDESC_L1_DESC_DWORDS 1 +#define CTXDESC_L1_DESC_VALID 1 +#define CTXDESC_L1_DESC_L2PTR_MASK GENMASK_ULL(51, 12) + #define CTXDESC_CD_DWORDS 8 #define CTXDESC_CD_0_TCR_T0SZ GENMASK_ULL(5, 0) #define ARM64_TCR_T0SZ GENMASK_ULL(5, 0) @@ -575,7 +589,12 @@ struct arm_smmu_cd_table { }; struct arm_smmu_s1_cfg { - struct arm_smmu_cd_table table; + /* Leaf tables or linear table */ + struct arm_smmu_cd_table *tables; + size_t num_tables; + /* First level tables, when two levels are used */ + __le64 *l1ptr; + dma_addr_t l1ptr_dma; struct arm_smmu_ctx_desc cd; u8 s1fmt; u8 s1cdmax; @@ -1521,9 +1540,48 @@ static void arm_smmu_free_cd_leaf_table(struct arm_smmu_device *smmu, { size_t size = num_entries * (CTXDESC_CD_DWORDS << 3); + if (!table->ptr) + return; dmam_free_coherent(smmu->dev, size, table->ptr, table->ptr_dma); } +static void arm_smmu_write_cd_l1_desc(__le64 *dst, + struct arm_smmu_cd_table *table) +{ + u64 val = (table->ptr_dma & CTXDESC_L1_DESC_L2PTR_MASK) | + CTXDESC_L1_DESC_VALID; + + WRITE_ONCE(*dst, cpu_to_le64(val)); +} + +static __le64 *arm_smmu_get_cd_ptr(struct arm_smmu_domain *smmu_domain, + u32 ssid) +{ + __le64 *l1ptr; + unsigned int idx; + struct arm_smmu_cd_table *table; + struct arm_smmu_device *smmu = smmu_domain->smmu; + struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg; + + if (cfg->s1fmt == STRTAB_STE_0_S1FMT_LINEAR) + return cfg->tables[0].ptr + ssid * CTXDESC_CD_DWORDS; + + idx = ssid >> CTXDESC_SPLIT; + table = &cfg->tables[idx]; + if (!table->ptr) { + if (arm_smmu_alloc_cd_leaf_table(smmu, table, + CTXDESC_L2_ENTRIES)) + return NULL; + + l1ptr = cfg->l1ptr + idx * CTXDESC_L1_DESC_DWORDS; + arm_smmu_write_cd_l1_desc(l1ptr, table); + /* An invalid L1CD can be cached */ + arm_smmu_sync_cd(smmu_domain, ssid, false); + } + idx = ssid & (CTXDESC_L2_ENTRIES - 1); + return table->ptr + idx * CTXDESC_CD_DWORDS; +} + static u64 arm_smmu_cpu_tcr_to_cd(u64 tcr) { u64 val = 0; @@ -1556,8 +1614,14 @@ static int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, u64 val; bool cd_live; struct arm_smmu_device *smmu = smmu_domain->smmu; - __le64 *cdptr = smmu_domain->s1_cfg.table.ptr + ssid * - CTXDESC_CD_DWORDS; + __le64 *cdptr; + + if (WARN_ON(ssid >= (1 << smmu_domain->s1_cfg.s1cdmax))) + return -E2BIG; + + cdptr = arm_smmu_get_cd_ptr(smmu_domain, ssid); + if (!cdptr) + return -ENOMEM; val = le64_to_cpu(cdptr[0]); cd_live = !!(val & CTXDESC_CD_0_V); @@ -1604,20 +1668,87 @@ static int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, static int arm_smmu_alloc_cd_tables(struct arm_smmu_domain *smmu_domain) { + int ret; + size_t size = 0; + size_t max_contexts; struct arm_smmu_device *smmu = smmu_domain->smmu; struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg; - cfg->s1fmt = STRTAB_STE_0_S1FMT_LINEAR; - return arm_smmu_alloc_cd_leaf_table(smmu, &cfg->table, - 1 << cfg->s1cdmax); + max_contexts = 1 << cfg->s1cdmax; + + if (!(smmu->features & ARM_SMMU_FEAT_2_LVL_CDTAB) || + max_contexts <= CTXDESC_L2_ENTRIES) { + cfg->s1fmt = STRTAB_STE_0_S1FMT_LINEAR; + cfg->num_tables = 1; + } else { + cfg->s1fmt = STRTAB_STE_0_S1FMT_64K_L2; + cfg->num_tables = DIV_ROUND_UP(max_contexts, + CTXDESC_L2_ENTRIES); + + size = cfg->num_tables * (CTXDESC_L1_DESC_DWORDS << 3); + cfg->l1ptr = dmam_alloc_coherent(smmu->dev, size, + &cfg->l1ptr_dma, + GFP_KERNEL); + if (!cfg->l1ptr) { + dev_warn(smmu->dev, + "failed to allocate L1 context table\n"); + return -ENOMEM; + } + } + + cfg->tables = devm_kzalloc(smmu->dev, sizeof(struct arm_smmu_cd_table) * + cfg->num_tables, GFP_KERNEL); + if (!cfg->tables) { + ret = -ENOMEM; + goto err_free_l1; + } + + /* + * Only allocate a leaf table for linear case. With two levels, leaf + * tables are allocated lazily. + */ + if (cfg->s1fmt == STRTAB_STE_0_S1FMT_LINEAR) { + ret = arm_smmu_alloc_cd_leaf_table(smmu, &cfg->tables[0], + max_contexts); + if (ret) + goto err_free_tables; + } + + return 0; + +err_free_tables: + devm_kfree(smmu->dev, cfg->tables); + cfg->tables = NULL; +err_free_l1: + if (cfg->l1ptr) { + dmam_free_coherent(smmu->dev, size, cfg->l1ptr, cfg->l1ptr_dma); + cfg->l1ptr = NULL; + cfg->l1ptr_dma = 0; + } + return ret; } static void arm_smmu_free_cd_tables(struct arm_smmu_domain *smmu_domain) { + int i; struct arm_smmu_device *smmu = smmu_domain->smmu; struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg; + size_t num_leaf_entries = 1 << cfg->s1cdmax; + struct arm_smmu_cd_table *table = cfg->tables; + + if (cfg->l1ptr) { + size_t size = cfg->num_tables * (CTXDESC_L1_DESC_DWORDS << 3); - arm_smmu_free_cd_leaf_table(smmu, &cfg->table, 1 << cfg->s1cdmax); + dmam_free_coherent(smmu->dev, size, cfg->l1ptr, cfg->l1ptr_dma); + cfg->l1ptr = NULL; + cfg->l1ptr_dma = 0; + num_leaf_entries = CTXDESC_L2_ENTRIES; + } + + for (i = 0; i < cfg->num_tables; i++, table++) + arm_smmu_free_cd_leaf_table(smmu, table, num_leaf_entries); + devm_kfree(smmu->dev, cfg->tables); + cfg->tables = NULL; } /* Stream table manipulation functions */ @@ -1737,6 +1868,9 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid, } if (s1_cfg) { + dma_addr_t ptr_dma = s1_cfg->l1ptr ? s1_cfg->l1ptr_dma : + s1_cfg->tables[0].ptr_dma; + BUG_ON(ste_live); dst[1] = cpu_to_le64( FIELD_PREP(STRTAB_STE_1_S1DSS, STRTAB_STE_1_S1DSS_SSID0) | @@ -1749,7 +1883,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid, !(smmu->features & ARM_SMMU_FEAT_STALL_FORCE)) dst[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD); - val |= (s1_cfg->table.ptr_dma & STRTAB_STE_0_S1CTXPTR_MASK) | + val |= (ptr_dma & STRTAB_STE_0_S1CTXPTR_MASK) | FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_S1_TRANS) | FIELD_PREP(STRTAB_STE_0_S1CDMAX, s1_cfg->s1cdmax) | FIELD_PREP(STRTAB_STE_0_S1FMT, s1_cfg->s1fmt); @@ -2265,7 +2399,7 @@ static void arm_smmu_domain_free(struct iommu_domain *domain) if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) { struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg; - if (cfg->table.ptr) { + if (cfg->tables) { arm_smmu_free_cd_tables(smmu_domain); arm_smmu_bitmap_free(smmu->asid_map, cfg->cd.asid); } -- 2.24.1 _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
