[RFCv2 0/2] iommu/smmu-v3: Workaround for hisilicon 161010801 erratum(reserve HW MSI)
shameer
shameerali.kolothum.thodi at huawei.com
Wed May 31 07:32:11 PDT 2017
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 the
associated ITS base address from a device IORT node.
2. Added quirk to SMMUv3 to retrieve the HW ITS address and replace
the default SW MSI reserve address based on the IORT SMMU model.
This is based on the following patches:
1. https://patchwork.kernel.org/patch/9740733/
2. https://patchwork.kernel.org/patch/9730491/
Thanks,
Shameer
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 new helper function to retrieve ITS base addr from IORT
node
iommu/arm-smmu-v3:Enable ACPI based HiSilicon erratum 161010801
drivers/acpi/arm64/iort.c | 47 +++++++++++++++++++++++++++++++++++---
drivers/iommu/arm-smmu-v3.c | 49 +++++++++++++++++++++++++++++++++++++---
drivers/irqchip/irq-gic-v3-its.c | 3 ++-
include/linux/acpi_iort.h | 8 ++++++-
4 files changed, 99 insertions(+), 8 deletions(-)
--
1.9.1
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