[PATCH 0/2] iommu/smmu-v3: Workaround for hisilicon 161010801 erratum(reserve HW MSI)

[shameer]

On certain HiSilicon platforms (Hip06/Hip07) the GIC ITS and
PCIe RC deviates from the standard implementation and this breaks
PCIe MSI functionality when SMMU is enabled.

The HiSilicon erratum 161010801 describes this limitation of certain
HiSilicon platforms to support the SMMU mappings for MSI transactions.
On these platforms GICv3 ITS translator is presented with the deviceID
by extending the MSI payload data to 64 bits to include the deviceID.
Hence, the PCIe controller on this platforms has to differentiate the
MSI payload against other DMA payload and has to modify the MSI payload.
This basically makes it difficult for this platforms to have a SMMU
translation for MSI.

This patch implements a ACPI table based quirk to reserve the hw msi
regions in the smmu-v3 driver which means these address regions will
not be translated and will be excluded from iova allocations.

To implement this quirk, the following changes are incorporated:

1. Added a generic helper function to IORT code to retrieve and
   reserve the HW ITS address regions.
2. Added quirk to SMMUv3 to reserve HW ITS address regions based
   on IORT SMMUv3 model.

This is based on the following patches:
1. https://patchwork.kernel.org/patch/9740733/
2. https://patchwork.kernel.org/patch/9730491/

Thanks,
Shameer

RFCv2 -->PATCH

Incorporated Lorenzo's review comments.

RFC v1 -->v2

Based on Robin's review comments,
-Removed  the generic erratum framework.
-Using IORT/MADT tables to retrieve the ITS base addr instead
 of vendor specific CSRT table.

shameer (2):
  acpi:iort: Add an IORT helper function to reserve HW ITS address
    regions for IOMMU drivers
  iommu/arm-smmu-v3:Enable ACPI based HiSilicon erratum 161010801

 drivers/acpi/arm64/iort.c        | 92 ++++++++++++++++++++++++++++++++++++++--
 drivers/iommu/arm-smmu-v3.c      | 27 +++++++++---
 drivers/irqchip/irq-gic-v3-its.c |  3 +-
 include/linux/acpi_iort.h        |  7 ++-
 4 files changed, 119 insertions(+), 10 deletions(-)

-- 
1.9.1