From 2505ec6f85ad864b76127f9662c6f3f315dff14f Mon Sep 17 00:00:00 2001 From: Jean-Philippe Brucker Date: Wed, 15 Jan 2020 13:52:34 +0100 Subject: iommu/arm-smmu-v3: Propagate ssid_bits Now that we support substream IDs, initialize s1cdmax with the number of SSID bits supported by a master and the SMMU. Context descriptor tables are allocated once for the first master attached to a domain. Therefore attaching multiple devices with different SSID sizes is tricky, and we currently don't support it. As a future improvement it would be nice to at least support attaching a SSID-capable device to a domain that isn't using SSID, by reallocating the SSID table. This would allow supporting a SSID-capable device that is in the same IOMMU group as a bridge, for example. Varying SSID size is less of a concern, since the PCIe specification "highly recommends" that devices supporting PASID implement all 20 bits of it. Tested-by: Zhangfei Gao Reviewed-by: Eric Auger Reviewed-by: Jonathan Cameron Signed-off-by: Jean-Philippe Brucker Signed-off-by: Will Deacon --- drivers/iommu/arm-smmu-v3.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) (limited to 'drivers/iommu') diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index b0e63de9009e..88a48256c11e 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -2250,6 +2250,7 @@ static void arm_smmu_domain_free(struct iommu_domain *domain) } static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain, + struct arm_smmu_master *master, struct io_pgtable_cfg *pgtbl_cfg) { int ret; @@ -2262,6 +2263,8 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain, if (asid < 0) return asid; + cfg->s1cdmax = master->ssid_bits; + ret = arm_smmu_alloc_cd_tables(smmu_domain); if (ret) goto out_free_asid; @@ -2284,6 +2287,7 @@ out_free_asid: } static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain, + struct arm_smmu_master *master, struct io_pgtable_cfg *pgtbl_cfg) { int vmid; @@ -2308,7 +2312,8 @@ static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain, return 0; } -static int arm_smmu_domain_finalise(struct iommu_domain *domain) +static int arm_smmu_domain_finalise(struct iommu_domain *domain, + struct arm_smmu_master *master) { int ret; unsigned long ias, oas; @@ -2316,6 +2321,7 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain) struct io_pgtable_cfg pgtbl_cfg; struct io_pgtable_ops *pgtbl_ops; int (*finalise_stage_fn)(struct arm_smmu_domain *, + struct arm_smmu_master *, struct io_pgtable_cfg *); struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); struct arm_smmu_device *smmu = smmu_domain->smmu; @@ -2370,7 +2376,7 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain) domain->geometry.aperture_end = (1UL << pgtbl_cfg.ias) - 1; domain->geometry.force_aperture = true; - ret = finalise_stage_fn(smmu_domain, &pgtbl_cfg); + ret = finalise_stage_fn(smmu_domain, master, &pgtbl_cfg); if (ret < 0) { free_io_pgtable_ops(pgtbl_ops); return ret; @@ -2523,7 +2529,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) if (!smmu_domain->smmu) { smmu_domain->smmu = smmu; - ret = arm_smmu_domain_finalise(domain); + ret = arm_smmu_domain_finalise(domain, master); if (ret) { smmu_domain->smmu = NULL; goto out_unlock; @@ -2535,6 +2541,13 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) dev_name(smmu->dev)); ret = -ENXIO; goto out_unlock; + } else if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1 && + master->ssid_bits != smmu_domain->s1_cfg.s1cdmax) { + dev_err(dev, + "cannot attach to incompatible domain (%u SSID bits != %u)\n", + smmu_domain->s1_cfg.s1cdmax, master->ssid_bits); + ret = -EINVAL; + goto out_unlock; } master->domain = smmu_domain; -- cgit v1.2.3