| Message ID | 20191209180514.272727-11-jean-philippe@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [v3,01/13] iommu/arm-smmu-v3: Drop __GFP_ZERO flag from DMA allocation | expand |
On Mon, 9 Dec 2019 19:05:11 +0100 Jean-Philippe Brucker <jean-philippe@linaro.org> wrote: > 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. > > Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> One tiny little comment inline. I really don't mind if you ignore it ;) Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > --- > drivers/iommu/arm-smmu-v3.c | 153 +++++++++++++++++++++++++++++++++--- > 1 file changed, 143 insertions(+), 10 deletions(-) > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index fc5119f34187..52adcdfda58b 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 +589,10 @@ struct arm_smmu_cd_table { > }; > > struct arm_smmu_s1_cfg { > - struct arm_smmu_cd_table table; > + struct arm_smmu_cd_table *tables; > + size_t num_tables; > + __le64 *l1ptr; > + dma_addr_t l1ptr_dma; > struct arm_smmu_ctx_desc cd; > u8 s1fmt; > u8 s1cdmax; > @@ -1521,9 +1538,53 @@ 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) { > + table = &cfg->tables[0]; > + idx = ssid; > + } else { > + idx = ssid >> CTXDESC_SPLIT; > + if (idx >= cfg->num_tables) > + return NULL; > + > + 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 +1617,10 @@ 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 = 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 +1667,87 @@ 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->l1ptr) { This might have been the tiniest bit clearer if the check matched the description by checking it's a linear table rather than what is kind of a side effect of it not being non linear. 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 +1867,9 @@ 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 +1882,7 @@ 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 +2398,7 @@ 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); > }
Hi Jean, On 12/9/19 7:05 PM, Jean-Philippe Brucker wrote: > 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. > > Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> > --- > drivers/iommu/arm-smmu-v3.c | 153 +++++++++++++++++++++++++++++++++--- > 1 file changed, 143 insertions(+), 10 deletions(-) > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index fc5119f34187..52adcdfda58b 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 +589,10 @@ struct arm_smmu_cd_table { > }; > > struct arm_smmu_s1_cfg { > - struct arm_smmu_cd_table table; > + struct arm_smmu_cd_table *tables; > + size_t num_tables; > + __le64 *l1ptr; you may add a comment saying that l1ptr and l1ptr_dma are only set/used in non linear case and one comment saying that "tables" represent leaf tables. > + dma_addr_t l1ptr_dma; > struct arm_smmu_ctx_desc cd; > u8 s1fmt; > u8 s1cdmax; > @@ -1521,9 +1538,53 @@ 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) { > + table = &cfg->tables[0]; > + idx = ssid; > + } else { nit: you may avoid this extra indent by either returning above or go to a label. > + idx = ssid >> CTXDESC_SPLIT; > + if (idx >= cfg->num_tables) > + return NULL; > + > + 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 +1617,10 @@ 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 = arm_smmu_get_cd_ptr(smmu_domain, ssid); > + > + if (!cdptr) > + return -ENOMEM; -ENOMEM does not fit well with (idx >= cfg->num_tables) case Besides the idx is checked against the max table capacity only in non linear mode. Can't you check the ssid against cfg->s1cdmax earlier? > > val = le64_to_cpu(cdptr[0]); > cd_live = !!(val & CTXDESC_CD_0_V); > @@ -1604,20 +1667,87 @@ 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->l1ptr) { > + 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 +1867,9 @@ 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 +1882,7 @@ 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 +2398,7 @@ 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); > } > Otherwise looks good to me. Thanks Eric
On Wed, Dec 18, 2019 at 10:59:36AM +0100, Auger Eric wrote: > > struct arm_smmu_s1_cfg { > > - struct arm_smmu_cd_table table; > > + struct arm_smmu_cd_table *tables; > > + size_t num_tables; > > + __le64 *l1ptr; > you may add a comment saying that l1ptr and l1ptr_dma are only set/used > in non linear case and one comment saying that "tables" represent leaf > tables. I now have /* Leaf tables or linear table */ and /* First level tables, when two level are used */ but I'm not entirely convinced it adds value > > + dma_addr_t l1ptr_dma; > > struct arm_smmu_ctx_desc cd; > > u8 s1fmt; > > u8 s1cdmax; > > @@ -1521,9 +1538,53 @@ 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) { > > + table = &cfg->tables[0]; > > + idx = ssid; > > + } else { > nit: you may avoid this extra indent by either returning above or go to > a label. > > + idx = ssid >> CTXDESC_SPLIT; > > + if (idx >= cfg->num_tables) > > + return NULL; > > + > > + 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 +1617,10 @@ 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 = arm_smmu_get_cd_ptr(smmu_domain, ssid); > > + > > + if (!cdptr) > > + return -ENOMEM; > -ENOMEM does not fit well with (idx >= cfg->num_tables) case > Besides the idx is checked against the max table capacity only in non > linear mode. Can't you check the ssid against cfg->s1cdmax earlier? Ok, I'll move that check here Thanks, Jean
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index fc5119f34187..52adcdfda58b 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 +589,10 @@ struct arm_smmu_cd_table { }; struct arm_smmu_s1_cfg { - struct arm_smmu_cd_table table; + struct arm_smmu_cd_table *tables; + size_t num_tables; + __le64 *l1ptr; + dma_addr_t l1ptr_dma; struct arm_smmu_ctx_desc cd; u8 s1fmt; u8 s1cdmax; @@ -1521,9 +1538,53 @@ 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) { + table = &cfg->tables[0]; + idx = ssid; + } else { + idx = ssid >> CTXDESC_SPLIT; + if (idx >= cfg->num_tables) + return NULL; + + 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 +1617,10 @@ 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 = 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 +1667,87 @@ 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->l1ptr) { + 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 +1867,9 @@ 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 +1882,7 @@ 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 +2398,7 @@ 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); }
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. Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> --- drivers/iommu/arm-smmu-v3.c | 153 +++++++++++++++++++++++++++++++++--- 1 file changed, 143 insertions(+), 10 deletions(-)