[0/6] Add support for Translation Buffer Units

Message

Georgi Djakov Oct. 19, 2023, 2:19 a.m. UTC

The TCUs (Translation Control Units) and TBUs (Translation Buffer
Units) are key components of the ARM MMU-500. Multiple TBUs are
connected to a single TCU over an interconnect. Each TBU contains
a TLB that caches page tables. The MMU-500 implements a TBU for each
connected master, and the TBU is designed, so that it is local to the
master.

The Qualcomm sdm845 platform has an implementation of the ARM SMMU-500,
that consists of a single TCU and multiple TBUs. Support for the TCU
is already present and this patchset is adds support for TBUs that
allow us to use some of the debug features to include more info when
a context fault occurs.

Each TBU requires some resources like power-domains, interconnects and
clocks to be described in DT. These resources will be being controlled
by the TBU driver when they in use.

Georgi Djakov (6):
  dt-bindings: iommu: Add Translation Buffer Unit bindings
  iommu/arm-smmu-qcom: Add support for TBUs
  iommu/arm-smmu-qcom: Add Qualcomm TBU driver
  iommu/arm-smmu: Allow using a threaded handler for context interrupts
  iommu/arm-smmu-qcom: Use a custom context fault handler for sdm845
  arm64: dts: qcom: sdm845: Add DT nodes for the TBUs

 .../devicetree/bindings/iommu/arm,smmu.yaml   |  13 +
 .../bindings/iommu/qcom,qsmmuv500-tbu.yaml    |  67 +++
 arch/arm64/boot/dts/qcom/sdm845.dtsi          |  85 +++
 drivers/iommu/Kconfig                         |   8 +
 drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c    | 544 ++++++++++++++++++
 drivers/iommu/arm/arm-smmu/arm-smmu-qcom.h    |   4 +-
 drivers/iommu/arm/arm-smmu/arm-smmu.c         |  12 +-
 drivers/iommu/arm/arm-smmu/arm-smmu.h         |   3 +
 8 files changed, 733 insertions(+), 3 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/iommu/qcom,qsmmuv500-tbu.yaml