> From: Lu Baolu <baolu...@linux.intel.com> > Sent: Thursday, May 19, 2022 3:21 PM > > Use this field to keep the number of supported PASIDs that an IOMMU > hardware is able to support. This is a generic attribute of an IOMMU > and lifting it into the per-IOMMU device structure makes it possible > to allocate a PASID for device without calls into the IOMMU drivers. > Any iommu driver which suports PASID related features should set this > field before enabling them on the devices. > > Signed-off-by: Lu Baolu <baolu...@linux.intel.com> > Reviewed-by: Jean-Philippe Brucker <jean-phili...@linaro.org> > --- > include/linux/iommu.h | 2 ++ > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 1 + > drivers/iommu/intel/dmar.c | 4 ++++ > 3 files changed, 7 insertions(+) > > diff --git a/include/linux/iommu.h b/include/linux/iommu.h > index 5e1afe169549..da423e87f248 100644 > --- a/include/linux/iommu.h > +++ b/include/linux/iommu.h > @@ -318,12 +318,14 @@ struct iommu_domain_ops { > * @list: Used by the iommu-core to keep a list of registered iommus > * @ops: iommu-ops for talking to this iommu > * @dev: struct device for sysfs handling > + * @pasids: number of supported PASIDs > */ > struct iommu_device { > struct list_head list; > const struct iommu_ops *ops; > struct fwnode_handle *fwnode; > struct device *dev; > + u32 pasids;
max_pasid or nr_pasids? > }; > > /** > diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > index 88817a3376ef..6e2cd082c670 100644 > --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > @@ -3546,6 +3546,7 @@ static int arm_smmu_device_hw_probe(struct > arm_smmu_device *smmu) > /* SID/SSID sizes */ > smmu->ssid_bits = FIELD_GET(IDR1_SSIDSIZE, reg); > smmu->sid_bits = FIELD_GET(IDR1_SIDSIZE, reg); > + smmu->iommu.pasids = smmu->ssid_bits; > > /* > * If the SMMU supports fewer bits than would fill a single L2 stream > diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c > index 4de960834a1b..1c3cf267934d 100644 > --- a/drivers/iommu/intel/dmar.c > +++ b/drivers/iommu/intel/dmar.c > @@ -1126,6 +1126,10 @@ static int alloc_iommu(struct dmar_drhd_unit > *drhd) > > raw_spin_lock_init(&iommu->register_lock); > > + /* Supports full 20-bit PASID in scalable mode. */ > + if (ecap_pasid(iommu->ecap)) > + iommu->iommu.pasids = 1UL << 20; > + supported pasid bits is reported by ecap_pss(). I don't think we should assume 20bits here. > /* > * This is only for hotplug; at boot time intel_iommu_enabled won't > * be set yet. When intel_iommu_init() runs, it registers the units > -- > 2.25.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu