On Fri, 8 Nov 2019 16:25:05 +0100 Jean-Philippe Brucker <[email protected]> wrote:
> At the moment, the SMMUv3 driver implements only one stage-1 or stage-2 > page directory per device. However SMMUv3 allows more than one address > space for some devices, by providing multiple stage-1 page directories. In > addition to the Stream ID (SID), that identifies a device, we can now have > Substream IDs (SSID) identifying an address space. In PCIe, 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 > +--------+ +-------+ +-------+ > : : : : : : > +--------+ +-------+ +-------+ > > Implement a single level of context descriptor table for now, but as with > stream and page tables, an SSID can be split to index multiple levels of > tables. > > Signed-off-by: Jean-Philippe Brucker <[email protected]> Looks good to me. Reviewed-by: Jonathan Cameron <[email protected]> > --- > drivers/iommu/arm-smmu-v3.c | 132 ++++++++++++++++++++++++++++++------ > 1 file changed, 111 insertions(+), 21 deletions(-) > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index 122bed0168a3..df7d45503c65 100644 > --- a/drivers/iommu/arm-smmu-v3.c > +++ b/drivers/iommu/arm-smmu-v3.c > @@ -227,6 +227,11 @@ > #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 > @@ -329,6 +334,7 @@ > #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) > @@ -446,8 +452,11 @@ 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; > @@ -566,6 +575,7 @@ struct arm_smmu_cd_table { > }; > > struct arm_smmu_s1_cfg { > + u8 s1fmt; > u8 s1cdmax; > struct arm_smmu_cd_table table; > struct arm_smmu_ctx_desc cd; > @@ -860,10 +870,16 @@ 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); > @@ -1456,6 +1472,33 @@ static int arm_smmu_cmdq_issue_sync(struct > arm_smmu_device *smmu) > } > > /* Context descriptor manipulation functions */ > +static void arm_smmu_sync_cd(struct arm_smmu_domain *smmu_domain, > + int ssid, bool leaf) > +{ > + size_t i; > + unsigned long flags; > + struct arm_smmu_master *master; > + struct arm_smmu_device *smmu = smmu_domain->smmu; > + struct arm_smmu_cmdq_ent cmd = { > + .opcode = CMDQ_OP_CFGI_CD, > + .cfgi = { > + .ssid = ssid, > + .leaf = leaf, > + }, > + }; > + > + spin_lock_irqsave(&smmu_domain->devices_lock, flags); > + list_for_each_entry(master, &smmu_domain->devices, domain_head) { > + for (i = 0; i < master->num_sids; i++) { > + cmd.cfgi.sid = master->sids[i]; > + arm_smmu_cmdq_issue_cmd(smmu, &cmd); > + } > + } > + spin_unlock_irqrestore(&smmu_domain->devices_lock, flags); > + > + arm_smmu_cmdq_issue_sync(smmu); > +} > + > static int arm_smmu_alloc_cd_leaf_table(struct arm_smmu_device *smmu, > struct arm_smmu_cd_table *table, > size_t num_entries) > @@ -1481,6 +1524,11 @@ static void arm_smmu_free_cd_leaf_table(struct > arm_smmu_device *smmu, > dmam_free_coherent(smmu->dev, size, table->ptr, table->ptr_dma); > } > > +static __le64 *arm_smmu_get_cd_ptr(struct arm_smmu_s1_cfg *cfg, u32 ssid) > +{ > + return cfg->table.ptr + ssid * CTXDESC_CD_DWORDS; > +} > + > static u64 arm_smmu_cpu_tcr_to_cd(u64 tcr) > { > u64 val = 0; > @@ -1498,34 +1546,68 @@ static u64 arm_smmu_cpu_tcr_to_cd(u64 tcr) > return val; > } > > -static void arm_smmu_write_ctx_desc(struct arm_smmu_device *smmu, > - struct arm_smmu_s1_cfg *cfg) > +static int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, > + int ssid, struct arm_smmu_ctx_desc *cd) > { > u64 val; > - __le64 *cdptr = cfg->table.ptr; > + bool cd_live; > + struct arm_smmu_device *smmu = smmu_domain->smmu; > + __le64 *cdptr = arm_smmu_get_cd_ptr(&smmu_domain->s1_cfg, ssid); > > /* > - * 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. > + * (3) Update ASID of a CD. Atomically write the first 64 bits of the > + * CD, then invalidate the old entry and mappings. > + * (4) Remove a secondary CD. > */ > - val = arm_smmu_cpu_tcr_to_cd(cfg->cd.tcr) | > -#ifdef __BIG_ENDIAN > - 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, cfg->cd.asid) | > - CTXDESC_CD_0_V; > > - /* STALL_MODEL==0b10 && CD.S==0 is ILLEGAL */ > - if (smmu->features & ARM_SMMU_FEAT_STALL_FORCE) > - val |= CTXDESC_CD_0_S; > + if (!cdptr) > + return -ENOMEM; > > - cdptr[0] = cpu_to_le64(val); > + val = le64_to_cpu(cdptr[0]); > + cd_live = !!(val & CTXDESC_CD_0_V); > > - val = cfg->cd.ttbr & CTXDESC_CD_1_TTB0_MASK; > - cdptr[1] = cpu_to_le64(val); > + if (!cd) { /* (4) */ > + val = 0; > + } else if (cd_live) { /* (3) */ > + val &= ~CTXDESC_CD_0_ASID; > + val |= FIELD_PREP(CTXDESC_CD_0_ASID, cd->asid); > + /* > + * 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); > > - cdptr[3] = cpu_to_le64(cfg->cd.mair); > + /* > + * STE is live, and the SMMU might fetch this CD at any > + * time. Ensure that it observes the rest of the CD before we > + * enable it. > + */ > + arm_smmu_sync_cd(smmu_domain, ssid, true); > + > + val = arm_smmu_cpu_tcr_to_cd(cd->tcr) | > +#ifdef __BIG_ENDIAN > + 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->asid) | > + CTXDESC_CD_0_V; > + > + /* STALL_MODEL==0b10 && CD.S==0 is ILLEGAL */ > + if (smmu->features & ARM_SMMU_FEAT_STALL_FORCE) > + val |= CTXDESC_CD_0_S; > + } > + > + WRITE_ONCE(cdptr[0], cpu_to_le64(val)); > + arm_smmu_sync_cd(smmu_domain, ssid, true); > + return 0; > } > > static int arm_smmu_alloc_cd_tables(struct arm_smmu_domain *smmu_domain) > @@ -1533,6 +1615,7 @@ static int arm_smmu_alloc_cd_tables(struct > arm_smmu_domain *smmu_domain) > 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); > } > @@ -1664,6 +1747,7 @@ static void arm_smmu_write_strtab_ent(struct > arm_smmu_master *master, u32 sid, > if (s1_cfg) { > 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) | > @@ -1674,7 +1758,9 @@ static void arm_smmu_write_strtab_ent(struct > arm_smmu_master *master, u32 sid, > dst[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD); > > val |= (s1_cfg->table.ptr_dma & 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, s1_cfg->s1cdmax) | > + FIELD_PREP(STRTAB_STE_0_S1FMT, s1_cfg->s1fmt); > } > > if (s2_cfg) { > @@ -2224,10 +2310,14 @@ static int arm_smmu_domain_finalise_s1(struct > arm_smmu_domain *smmu_domain, > cfg->cd.tcr = pgtbl_cfg->arm_lpae_s1_cfg.tcr; > cfg->cd.mair = pgtbl_cfg->arm_lpae_s1_cfg.mair[0]; > > - arm_smmu_write_ctx_desc(smmu, cfg); > + ret = arm_smmu_write_ctx_desc(smmu_domain, 0, &cfg->cd); > + if (ret) > + goto out_free_tables; > > return 0; > > +out_free_tables: > + arm_smmu_free_cd_tables(smmu_domain); > out_free_asid: > arm_smmu_bitmap_free(smmu->asid_map, asid); > return ret; _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
