lkml.org 
[lkml]   [2022]   [Mar]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRE: [PATCH RFC v2 01/11] iommu: Add pasid_bits field in struct dev_iommu
    Date
    > From: Lu Baolu <baolu.lu@linux.intel.com>
    > Sent: Tuesday, March 29, 2022 1:38 PM
    >
    > Use this field to save the pasid/ssid bits that a device is able to
    > support with its IOMMU hardware. It is a generic attribute of a device
    > and lifting it into the per-device dev_iommu struct 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 features are enabled on the devices.

    Miss a clarification for non-PCI SVA as discussed here:

    https://lore.kernel.org/all/85d61ad6-0cf0-ac65-3312-32d0cdeb1b27@linux.intel.com/


    >
    > Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
    > ---
    > include/linux/iommu.h | 1 +
    > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 2 ++
    > drivers/iommu/intel/iommu.c | 5 ++++-
    > 3 files changed, 7 insertions(+), 1 deletion(-)
    >
    > diff --git a/include/linux/iommu.h b/include/linux/iommu.h
    > index 6ef2df258673..36f43af0af53 100644
    > --- a/include/linux/iommu.h
    > +++ b/include/linux/iommu.h
    > @@ -368,6 +368,7 @@ struct dev_iommu {
    > struct iommu_fwspec *fwspec;
    > struct iommu_device *iommu_dev;
    > void *priv;
    > + unsigned int pasid_bits;
    > };
    >
    > int iommu_device_register(struct iommu_device *iommu,
    > 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 627a3ed5ee8f..afc63fce6107 100644
    > --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
    > +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
    > @@ -2681,6 +2681,8 @@ static struct iommu_device
    > *arm_smmu_probe_device(struct device *dev)
    > smmu->features & ARM_SMMU_FEAT_STALL_FORCE)
    > master->stall_enabled = true;
    >
    > + dev->iommu->pasid_bits = master->ssid_bits;
    > +
    > return &smmu->iommu;
    >
    > err_free_master:
    > diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
    > index 6f7485c44a4b..c1b91bce1530 100644
    > --- a/drivers/iommu/intel/iommu.c
    > +++ b/drivers/iommu/intel/iommu.c
    > @@ -4587,8 +4587,11 @@ static struct iommu_device
    > *intel_iommu_probe_device(struct device *dev)
    > if (pasid_supported(iommu)) {
    > int features = pci_pasid_features(pdev);
    >
    > - if (features >= 0)
    > + if (features >= 0) {
    > info->pasid_supported = features | 1;
    > + dev->iommu->pasid_bits =
    > + fls(pci_max_pasids(pdev)) - 1;
    > + }
    > }
    >
    > if (info->ats_supported && ecap_prs(iommu->ecap)
    > &&
    > --
    > 2.25.1

    \
     
     \ /
      Last update: 2022-03-30 09:06    [W:2.495 / U:0.356 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site