[v2,0/7] Add PCI ATS support to Arm SMMUv3

Message

Jean-Philippe Brucker April 9, 2019, 4:52 p.m. UTC

This series enables PCI ATS in SMMUv3. Changes since v1 [1]:

* Simplify the SMMU structures (patches 2-4 are new).

* Don't enable ATS for devices that are attached to a bypass domain,
  because in that case a translation request would cause F_BAD_ATS_TREQ.
  Translation requests in that case cause F_BAD_ATS_TREQ. Enable ATS in
  attach_dev() rather than add_device().

* Enable ATS for stage-1 and stage-2 STEs alike. There is no benefit to
  disabling ATS for stage-2 domains.

[1] https://www.spinics.net/lists/arm-kernel/msg714628.html

Jean-Philippe Brucker (7):
  ACPI/IORT: Check ATS capability in root complex nodes
  iommu/arm-smmu-v3: Rename arm_smmu_master_data to arm_smmu_master
  iommu/arm-smmu-v3: Store SteamIDs in master
  iommu/arm-smmu-v3: Add a master->domain pointer
  iommu/arm-smmu-v3: Link domains and devices
  iommu/arm-smmu-v3: Add support for PCI ATS
  iommu/arm-smmu-v3: Disable tagged pointers

 drivers/acpi/arm64/iort.c   |  11 ++
 drivers/iommu/arm-smmu-v3.c | 340 ++++++++++++++++++++++++++++--------
 include/linux/iommu.h       |   4 +
 3 files changed, 286 insertions(+), 69 deletions(-)

Comments

Will Deacon April 15, 2019, 1:20 p.m. UTC | #1

Hi Jean-Philippe,

On Tue, Apr 09, 2019 at 05:52:38PM +0100, Jean-Philippe Brucker wrote:
> This series enables PCI ATS in SMMUv3. Changes since v1 [1]:
> 
> * Simplify the SMMU structures (patches 2-4 are new).
> 
> * Don't enable ATS for devices that are attached to a bypass domain,
>   because in that case a translation request would cause F_BAD_ATS_TREQ.
>   Translation requests in that case cause F_BAD_ATS_TREQ. Enable ATS in
>   attach_dev() rather than add_device().
> 
> * Enable ATS for stage-1 and stage-2 STEs alike. There is no benefit to
>   disabling ATS for stage-2 domains.
> 
> [1] https://www.spinics.net/lists/arm-kernel/msg714628.html
> 
> Jean-Philippe Brucker (7):
>   ACPI/IORT: Check ATS capability in root complex nodes
>   iommu/arm-smmu-v3: Rename arm_smmu_master_data to arm_smmu_master
>   iommu/arm-smmu-v3: Store SteamIDs in master
>   iommu/arm-smmu-v3: Add a master->domain pointer
>   iommu/arm-smmu-v3: Link domains and devices
>   iommu/arm-smmu-v3: Add support for PCI ATS
>   iommu/arm-smmu-v3: Disable tagged pointers

Patches 2, 3, 4, 5 and 7 look fine to me. I've left some comments on the
other two.

Cheers,

Will