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iommu/arm-smmu-v3: Propagate ssid_bits

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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 <zhangfei.gao@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Jean-Philippe Brucker 2020-01-15 13:52:34 +01:00 committed by Will Deacon
parent 87f42391f6
commit 2505ec6f85
1 changed files with 16 additions and 3 deletions
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19
drivers/iommu/arm-smmu-v3.c
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@ -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;