| Message ID | 20191108152508.4039168-9-jean-philippe@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | iommu: Add PASID support to Arm SMMUv3 | expand |
On Fri, 8 Nov 2019 16:25:08 +0100 Jean-Philippe Brucker <jean-philippe@linaro.org> wrote: > Enable PASID for PCI devices that support it. Since the SSID tables are > allocated by arm_smmu_attach_dev(), PASID has to be enabled early enough. > arm_smmu_dev_feature_enable() would be too late, since by that time the > main DMA domain has already been attached. Do it in add_device() instead. > > Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Seems straightforward. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Thanks for working on this stuff. I hope we an move to get the rest of the SVA elements lined up behind it so everything moves quickly in the next cycle (or two). Jonathan > --- > drivers/iommu/arm-smmu-v3.c | 51 ++++++++++++++++++++++++++++++++++++- > 1 file changed, 50 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index 88ec0bf33492..3ee313c08325 100644 > --- a/drivers/iommu/arm-smmu-v3.c > +++ b/drivers/iommu/arm-smmu-v3.c > @@ -2633,6 +2633,49 @@ static void arm_smmu_disable_ats(struct arm_smmu_master *master) > atomic_dec(&smmu_domain->nr_ats_masters); > } > > +static int arm_smmu_enable_pasid(struct arm_smmu_master *master) > +{ > + int ret; > + int features; > + int num_pasids; > + struct pci_dev *pdev; > + > + if (!dev_is_pci(master->dev)) > + return -ENOSYS; > + > + pdev = to_pci_dev(master->dev); > + > + features = pci_pasid_features(pdev); > + if (features < 0) > + return -ENOSYS; > + > + num_pasids = pci_max_pasids(pdev); > + if (num_pasids <= 0) > + return -ENOSYS; > + > + ret = pci_enable_pasid(pdev, features); > + if (!ret) > + master->ssid_bits = min_t(u8, ilog2(num_pasids), > + master->smmu->ssid_bits); > + return ret; > +} > + > +static void arm_smmu_disable_pasid(struct arm_smmu_master *master) > +{ > + struct pci_dev *pdev; > + > + if (!dev_is_pci(master->dev)) > + return; > + > + pdev = to_pci_dev(master->dev); > + > + if (!pdev->pasid_enabled) > + return; > + > + master->ssid_bits = 0; > + pci_disable_pasid(pdev); > +} > + > static void arm_smmu_detach_dev(struct arm_smmu_master *master) > { > unsigned long flags; > @@ -2841,13 +2884,16 @@ static int arm_smmu_add_device(struct device *dev) > > master->ssid_bits = min(smmu->ssid_bits, fwspec->num_pasid_bits); > > + /* Note that PASID must be enabled before, and disabled after ATS */ > + arm_smmu_enable_pasid(master); > + > if (!(smmu->features & ARM_SMMU_FEAT_2_LVL_CDTAB)) > master->ssid_bits = min_t(u8, master->ssid_bits, > CTXDESC_LINEAR_CDMAX); > > ret = iommu_device_link(&smmu->iommu, dev); > if (ret) > - goto err_free_master; > + goto err_disable_pasid; > > group = iommu_group_get_for_dev(dev); > if (IS_ERR(group)) { > @@ -2860,6 +2906,8 @@ static int arm_smmu_add_device(struct device *dev) > > err_unlink: > iommu_device_unlink(&smmu->iommu, dev); > +err_disable_pasid: > + arm_smmu_disable_pasid(master); > err_free_master: > kfree(master); > fwspec->iommu_priv = NULL; > @@ -2880,6 +2928,7 @@ static void arm_smmu_remove_device(struct device *dev) > arm_smmu_detach_dev(master); > iommu_group_remove_device(dev); > iommu_device_unlink(&smmu->iommu, dev); > + arm_smmu_disable_pasid(master); > kfree(master); > iommu_fwspec_free(dev); > }
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index 88ec0bf33492..3ee313c08325 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -2633,6 +2633,49 @@ static void arm_smmu_disable_ats(struct arm_smmu_master *master) atomic_dec(&smmu_domain->nr_ats_masters); } +static int arm_smmu_enable_pasid(struct arm_smmu_master *master) +{ + int ret; + int features; + int num_pasids; + struct pci_dev *pdev; + + if (!dev_is_pci(master->dev)) + return -ENOSYS; + + pdev = to_pci_dev(master->dev); + + features = pci_pasid_features(pdev); + if (features < 0) + return -ENOSYS; + + num_pasids = pci_max_pasids(pdev); + if (num_pasids <= 0) + return -ENOSYS; + + ret = pci_enable_pasid(pdev, features); + if (!ret) + master->ssid_bits = min_t(u8, ilog2(num_pasids), + master->smmu->ssid_bits); + return ret; +} + +static void arm_smmu_disable_pasid(struct arm_smmu_master *master) +{ + struct pci_dev *pdev; + + if (!dev_is_pci(master->dev)) + return; + + pdev = to_pci_dev(master->dev); + + if (!pdev->pasid_enabled) + return; + + master->ssid_bits = 0; + pci_disable_pasid(pdev); +} + static void arm_smmu_detach_dev(struct arm_smmu_master *master) { unsigned long flags; @@ -2841,13 +2884,16 @@ static int arm_smmu_add_device(struct device *dev) master->ssid_bits = min(smmu->ssid_bits, fwspec->num_pasid_bits); + /* Note that PASID must be enabled before, and disabled after ATS */ + arm_smmu_enable_pasid(master); + if (!(smmu->features & ARM_SMMU_FEAT_2_LVL_CDTAB)) master->ssid_bits = min_t(u8, master->ssid_bits, CTXDESC_LINEAR_CDMAX); ret = iommu_device_link(&smmu->iommu, dev); if (ret) - goto err_free_master; + goto err_disable_pasid; group = iommu_group_get_for_dev(dev); if (IS_ERR(group)) { @@ -2860,6 +2906,8 @@ static int arm_smmu_add_device(struct device *dev) err_unlink: iommu_device_unlink(&smmu->iommu, dev); +err_disable_pasid: + arm_smmu_disable_pasid(master); err_free_master: kfree(master); fwspec->iommu_priv = NULL; @@ -2880,6 +2928,7 @@ static void arm_smmu_remove_device(struct device *dev) arm_smmu_detach_dev(master); iommu_group_remove_device(dev); iommu_device_unlink(&smmu->iommu, dev); + arm_smmu_disable_pasid(master); kfree(master); iommu_fwspec_free(dev); }
Enable PASID for PCI devices that support it. Since the SSID tables are allocated by arm_smmu_attach_dev(), PASID has to be enabled early enough. arm_smmu_dev_feature_enable() would be too late, since by that time the main DMA domain has already been attached. Do it in add_device() instead. Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> --- drivers/iommu/arm-smmu-v3.c | 51 ++++++++++++++++++++++++++++++++++++- 1 file changed, 50 insertions(+), 1 deletion(-) -- 2.23.0