> > At the moment, the SMMUv3 driver offers only one stage-1 or stage-2 > address space to each device. SMMUv3 allows to associate multiple address > spaces per device. In addition to the Stream ID (SID), that identifies a device, > we can now have Substream IDs (SSID) identifying an address space. > In PCIe lingo, SID is called Requester ID (RID) and SSID is called Process > Address-Space ID (PASID). > > Prepare the driver for SSID support, by adding context descriptor tables in > STEs (previously a single static context descriptor). A complete > stage-1 walk is now performed like this by the SMMU: > > Stream tables Ctx. tables Page tables > +--------+ ,------->+-------+ ,------->+-------+ > : : | : : | : : > +--------+ | +-------+ | +-------+ > SID->| STE |---' SSID->| CD |---' IOVA->| PTE |--> IPA > +--------+ +-------+ +-------+ > : : : : : : > +--------+ +-------+ +-------+ > > We only implement one level of context descriptor table for now, but as with > stream and page tables, an SSID can be split to target multiple levels of > tables. > > In all stream table entries, we set S1DSS=SSID0 mode, making translations > without an ssid use context descriptor 0. > > Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@xxxxxxx> > > --- > v1->v2: use GENMASK throughout SMMU patches > --- > drivers/iommu/arm-smmu-v3-context.c | 141 +++++++++++++++++++++------ > - > drivers/iommu/arm-smmu-v3.c | 82 +++++++++++++++- > drivers/iommu/iommu-pasid-table.h | 7 ++ > 3 files changed, 190 insertions(+), 40 deletions(-) > > diff --git a/drivers/iommu/arm-smmu-v3-context.c b/drivers/iommu/arm- > smmu-v3-context.c > index 15d3d02c59b2..0969a3626110 100644 > --- a/drivers/iommu/arm-smmu-v3-context.c > +++ b/drivers/iommu/arm-smmu-v3-context.c > @@ -62,11 +62,14 @@ struct arm_smmu_cd { #define > pasid_entry_to_cd(entry) \ > container_of((entry), struct arm_smmu_cd, entry) > > +struct arm_smmu_cd_table { > + __le64 *ptr; > + dma_addr_t ptr_dma; > +}; > + > struct arm_smmu_cd_tables { > struct iommu_pasid_table pasid; > - > - void *ptr; > - dma_addr_t ptr_dma; > + struct arm_smmu_cd_table table; > }; > > #define pasid_to_cd_tables(pasid_table) \ @@ -77,6 +80,36 @@ struct > arm_smmu_cd_tables { > > static DEFINE_IDA(asid_ida); > > +static int arm_smmu_alloc_cd_leaf_table(struct device *dev, > + struct arm_smmu_cd_table *desc, > + size_t num_entries) > +{ > + size_t size = num_entries * (CTXDESC_CD_DWORDS << 3); > + > + desc->ptr = dmam_alloc_coherent(dev, size, &desc->ptr_dma, > + GFP_ATOMIC | __GFP_ZERO); > + if (!desc->ptr) { > + dev_warn(dev, "failed to allocate context descriptor > table\n"); > + return -ENOMEM; > + } > + > + return 0; > +} > + > +static void arm_smmu_free_cd_leaf_table(struct device *dev, > + struct arm_smmu_cd_table *desc, > + size_t num_entries) > +{ > + size_t size = num_entries * (CTXDESC_CD_DWORDS << 3); > + > + dmam_free_coherent(dev, size, desc->ptr, desc->ptr_dma); } > + > +static __le64 *arm_smmu_get_cd_ptr(struct arm_smmu_cd_tables *tbl, > u32 > +ssid) { > + return tbl->table.ptr + ssid * CTXDESC_CD_DWORDS; } > + > static u64 arm_smmu_cpu_tcr_to_cd(u64 tcr) { > u64 val = 0; > @@ -95,34 +128,74 @@ static u64 arm_smmu_cpu_tcr_to_cd(u64 tcr) > return val; > } > > -static void arm_smmu_write_ctx_desc(struct arm_smmu_cd_tables *tbl, > - struct arm_smmu_cd *cd) > +static int arm_smmu_write_ctx_desc(struct arm_smmu_cd_tables *tbl, int > ssid, > + struct arm_smmu_cd *cd) > { > u64 val; > - __u64 *cdptr = tbl->ptr; > + bool cd_live; > + __le64 *cdptr = arm_smmu_get_cd_ptr(tbl, ssid); > struct arm_smmu_context_cfg *cfg = &tbl->pasid.cfg.arm_smmu; > > /* > - * We don't need to issue any invalidation here, as we'll invalidate > - * the STE when installing the new entry anyway. > + * This function handles the following cases: > + * > + * (1) Install primary CD, for normal DMA traffic (SSID = 0). > + * (2) Install a secondary CD, for SID+SSID traffic, followed by an > + * invalidation. > + * (3) Update ASID of primary CD. This is allowed by atomically > writing > + * the first 64 bits of the CD, followed by invalidation of the old > + * entry and mappings. > + * (4) Remove a secondary CD and invalidate it. > */ > - val = arm_smmu_cpu_tcr_to_cd(cd->tcr) | > + > + if (!cdptr) > + return -ENOMEM; > + > + val = le64_to_cpu(cdptr[0]); > + cd_live = !!(val & CTXDESC_CD_0_V); > + > + if (!cd) { /* (4) */ > + cdptr[0] = 0; > + } else if (cd_live) { /* (3) */ > + val &= ~CTXDESC_CD_0_ASID; > + val |= FIELD_PREP(CTXDESC_CD_0_ASID, cd->entry.tag); > + > + cdptr[0] = cpu_to_le64(val); > + /* > + * Until CD+TLB invalidation, both ASIDs may be used for > tagging > + * this substream's traffic > + */ > + } else { /* (1) and (2) */ > + cdptr[1] = cpu_to_le64(cd->ttbr & > CTXDESC_CD_1_TTB0_MASK); > + cdptr[2] = 0; > + cdptr[3] = cpu_to_le64(cd->mair); > + > + /* > + * STE is live, and the SMMU might fetch this CD at any > + * time. Ensure it observes the rest of the CD before we > + * enable it. > + */ > + iommu_pasid_flush(&tbl->pasid, ssid, true); > + > + > + val = arm_smmu_cpu_tcr_to_cd(cd->tcr) | > #ifdef __BIG_ENDIAN > - CTXDESC_CD_0_ENDI | > + CTXDESC_CD_0_ENDI | > #endif > - CTXDESC_CD_0_R | CTXDESC_CD_0_A | CTXDESC_CD_0_ASET | > - CTXDESC_CD_0_AA64 | FIELD_PREP(CTXDESC_CD_0_ASID, cd- > >entry.tag) | > - CTXDESC_CD_0_V; > + CTXDESC_CD_0_R | CTXDESC_CD_0_A | > CTXDESC_CD_0_ASET | > + CTXDESC_CD_0_AA64 | > + FIELD_PREP(CTXDESC_CD_0_ASID, cd->entry.tag) | > + CTXDESC_CD_0_V; > > - if (cfg->stall) > - val |= CTXDESC_CD_0_S; > + if (cfg->stall) > + val |= CTXDESC_CD_0_S; > > - cdptr[0] = cpu_to_le64(val); > + cdptr[0] = cpu_to_le64(val); > + } > > - val = cd->ttbr & CTXDESC_CD_1_TTB0_MASK; > - cdptr[1] = cpu_to_le64(val); > + iommu_pasid_flush(&tbl->pasid, ssid, true); > > - cdptr[3] = cpu_to_le64(cd->mair); > + return 0; > } > > static void arm_smmu_free_cd(struct iommu_pasid_entry *entry) @@ - > 190,8 +263,10 @@ static int arm_smmu_set_cd(struct > iommu_pasid_table_ops *ops, int pasid, > struct arm_smmu_cd_tables *tbl = pasid_ops_to_tables(ops); > struct arm_smmu_cd *cd = pasid_entry_to_cd(entry); > > - arm_smmu_write_ctx_desc(tbl, cd); > - return 0; > + if (WARN_ON(pasid > (1 << tbl->pasid.cfg.order))) > + return -EINVAL; > + > + return arm_smmu_write_ctx_desc(tbl, pasid, cd); > } > > static void arm_smmu_clear_cd(struct iommu_pasid_table_ops *ops, int > pasid, @@ -199,30 +274,26 @@ static void arm_smmu_clear_cd(struct > iommu_pasid_table_ops *ops, int pasid, { > struct arm_smmu_cd_tables *tbl = pasid_ops_to_tables(ops); > > - arm_smmu_write_ctx_desc(tbl, NULL); > + if (WARN_ON(pasid > (1 << tbl->pasid.cfg.order))) > + return; > + > + arm_smmu_write_ctx_desc(tbl, pasid, NULL); > } > > static struct iommu_pasid_table * > arm_smmu_alloc_cd_tables(struct iommu_pasid_table_cfg *cfg, void > *cookie) { > + int ret; > struct arm_smmu_cd_tables *tbl; > struct device *dev = cfg->iommu_dev; > > - if (cfg->order) { > - /* TODO: support SSID */ > - return NULL; > - } > - > tbl = devm_kzalloc(dev, sizeof(*tbl), GFP_KERNEL); > if (!tbl) > return NULL; > > - tbl->ptr = dmam_alloc_coherent(dev, CTXDESC_CD_DWORDS << 3, > - &tbl->ptr_dma, GFP_KERNEL | > __GFP_ZERO); > - if (!tbl->ptr) { > - dev_warn(dev, "failed to allocate context descriptor\n"); > + ret = arm_smmu_alloc_cd_leaf_table(dev, &tbl->table, 1 << cfg- > >order); > + if (ret) > goto err_free_tbl; > - } > > tbl->pasid.ops = (struct iommu_pasid_table_ops) { > .alloc_priv_entry = arm_smmu_alloc_priv_cd, > @@ -230,7 +301,8 @@ arm_smmu_alloc_cd_tables(struct > iommu_pasid_table_cfg *cfg, void *cookie) > .set_entry = arm_smmu_set_cd, > .clear_entry = arm_smmu_clear_cd, > }; > - cfg->base = tbl->ptr_dma; > + cfg->base = tbl->table.ptr_dma; > + cfg->arm_smmu.s1fmt = ARM_SMMU_S1FMT_LINEAR; > > return &tbl->pasid; > > @@ -246,8 +318,7 @@ static void arm_smmu_free_cd_tables(struct > iommu_pasid_table *pasid_table) > struct device *dev = cfg->iommu_dev; > struct arm_smmu_cd_tables *tbl = pasid_to_cd_tables(pasid_table); > > - dmam_free_coherent(dev, CTXDESC_CD_DWORDS << 3, > - tbl->ptr, tbl->ptr_dma); > + arm_smmu_free_cd_leaf_table(dev, &tbl->table, 1 << cfg->order); > devm_kfree(dev, tbl); > } > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index 68764a200e44..16b08f2fb8ac 100644 > --- a/drivers/iommu/arm-smmu-v3.c > +++ b/drivers/iommu/arm-smmu-v3.c > @@ -224,10 +224,14 @@ > #define STRTAB_STE_0_CFG_S2_TRANS 6 > > #define STRTAB_STE_0_S1FMT GENMASK_ULL(5, 4) > -#define STRTAB_STE_0_S1FMT_LINEAR 0 > #define STRTAB_STE_0_S1CTXPTR_MASK GENMASK_ULL(51, 6) > #define STRTAB_STE_0_S1CDMAX GENMASK_ULL(63, 59) > > +#define STRTAB_STE_1_S1DSS GENMASK_ULL(1, 0) > +#define STRTAB_STE_1_S1DSS_TERMINATE 0x0 > +#define STRTAB_STE_1_S1DSS_BYPASS 0x1 > +#define STRTAB_STE_1_S1DSS_SSID0 0x2 > + > #define STRTAB_STE_1_S1C_CACHE_NC 0UL > #define STRTAB_STE_1_S1C_CACHE_WBRA 1UL > #define STRTAB_STE_1_S1C_CACHE_WT 2UL > @@ -275,6 +279,7 @@ > #define CMDQ_PREFETCH_1_SIZE GENMASK_ULL(4, 0) > #define CMDQ_PREFETCH_1_ADDR_MASK GENMASK_ULL(63, 12) > > +#define CMDQ_CFGI_0_SSID GENMASK_ULL(31, 12) > #define CMDQ_CFGI_0_SID GENMASK_ULL(63, 32) > #define CMDQ_CFGI_1_LEAF (1UL << 0) > #define CMDQ_CFGI_1_RANGE GENMASK_ULL(4, 0) > @@ -381,8 +386,11 @@ struct arm_smmu_cmdq_ent { > > #define CMDQ_OP_CFGI_STE 0x3 > #define CMDQ_OP_CFGI_ALL 0x4 > + #define CMDQ_OP_CFGI_CD 0x5 > + #define CMDQ_OP_CFGI_CD_ALL 0x6 > struct { > u32 sid; > + u32 ssid; > union { > bool leaf; > u8 span; > @@ -555,6 +563,7 @@ struct arm_smmu_master_data { > struct list_head list; /* domain->devices */ > > struct device *dev; > + size_t ssid_bits; > }; > > /* SMMU private data for an IOMMU domain */ @@ -753,10 +762,16 @@ > static int arm_smmu_cmdq_build_cmd(u64 *cmd, struct > arm_smmu_cmdq_ent *ent) > cmd[1] |= FIELD_PREP(CMDQ_PREFETCH_1_SIZE, ent- > >prefetch.size); > cmd[1] |= ent->prefetch.addr & > CMDQ_PREFETCH_1_ADDR_MASK; > break; > + case CMDQ_OP_CFGI_CD: > + cmd[0] |= FIELD_PREP(CMDQ_CFGI_0_SSID, ent->cfgi.ssid); > + /* Fallthrough */ > case CMDQ_OP_CFGI_STE: > cmd[0] |= FIELD_PREP(CMDQ_CFGI_0_SID, ent->cfgi.sid); > cmd[1] |= FIELD_PREP(CMDQ_CFGI_1_LEAF, ent->cfgi.leaf); > break; > + case CMDQ_OP_CFGI_CD_ALL: > + cmd[0] |= FIELD_PREP(CMDQ_CFGI_0_SID, ent->cfgi.sid); > + break; > case CMDQ_OP_CFGI_ALL: > /* Cover the entire SID range */ > cmd[1] |= FIELD_PREP(CMDQ_CFGI_1_RANGE, 31); @@ - > 1048,8 +1063,11 @@ static void arm_smmu_write_strtab_ent(struct > arm_smmu_device *smmu, u32 sid, > } > > if (ste->s1_cfg) { > + struct iommu_pasid_table_cfg *cfg = &ste->s1_cfg->tables; > + > BUG_ON(ste_live); > dst[1] = cpu_to_le64( > + FIELD_PREP(STRTAB_STE_1_S1DSS, > STRTAB_STE_1_S1DSS_SSID0) | > FIELD_PREP(STRTAB_STE_1_S1CIR, > STRTAB_STE_1_S1C_CACHE_WBRA) | > FIELD_PREP(STRTAB_STE_1_S1COR, > STRTAB_STE_1_S1C_CACHE_WBRA) | > FIELD_PREP(STRTAB_STE_1_S1CSH, > ARM_SMMU_SH_ISH) | @@ -1063,7 +1081,9 @@ static void > arm_smmu_write_strtab_ent(struct arm_smmu_device *smmu, u32 sid, > dst[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD); > > val |= (ste->s1_cfg->tables.base & > STRTAB_STE_0_S1CTXPTR_MASK) | > - FIELD_PREP(STRTAB_STE_0_CFG, > STRTAB_STE_0_CFG_S1_TRANS); > + FIELD_PREP(STRTAB_STE_0_CFG, > STRTAB_STE_0_CFG_S1_TRANS) | > + FIELD_PREP(STRTAB_STE_0_S1CDMAX, cfg->order) | > + FIELD_PREP(STRTAB_STE_0_S1FMT, cfg- > >arm_smmu.s1fmt); > } > > if (ste->s2_cfg) { > @@ -1352,17 +1372,62 @@ static const struct iommu_gather_ops > arm_smmu_gather_ops = { }; > > /* PASID TABLE API */ > +static void __arm_smmu_sync_cd(struct arm_smmu_domain > *smmu_domain, > + struct arm_smmu_cmdq_ent *cmd) { > + size_t i; > + unsigned long flags; > + struct arm_smmu_master_data *master; > + struct arm_smmu_device *smmu = smmu_domain->smmu; > + > + spin_lock_irqsave(&smmu_domain->devices_lock, flags); > + list_for_each_entry(master, &smmu_domain->devices, list) { > + struct iommu_fwspec *fwspec = master->dev- > >iommu_fwspec; > + > + for (i = 0; i < fwspec->num_ids; i++) { > + cmd->cfgi.sid = fwspec->ids[i]; > + arm_smmu_cmdq_issue_cmd(smmu, cmd); > + } > + } > + spin_unlock_irqrestore(&smmu_domain->devices_lock, flags); > + > + __arm_smmu_tlb_sync(smmu); > +} > + > static void arm_smmu_sync_cd(void *cookie, int ssid, bool leaf) { > + struct arm_smmu_cmdq_ent cmd = { > + .opcode = CMDQ_OP_CFGI_CD_ALL, Hi Jean, here CMDQ_OP_CFGI_CD opcode 0x5. > + .cfgi = { > + .ssid = ssid, > + .leaf = leaf, > + }, > + }; > + > + __arm_smmu_sync_cd(cookie, &cmd); > } > Regards, Bharat