[PATCH v2 0/5] iommu: sun50i: Add Allwinner H616 support
Andre Przywara
andre.przywara at arm.com
Sun Jun 16 15:40:51 PDT 2024
Version two of this series adds a check that no physical address larger
than 4GB makes it into the PTEs: the map_pages() function returns an
error and prints a warning into dmesg to give users a clue why this
failed. I haven't tested whether this really happens, or whether the
32-bit DMA mask of the master devices already prevents this. In the
worst case this might fail on devices with 4GB of DRAM, but would always
work on smaller devices, which are arguably under bigger pressure to
find contiguous PA ranges. Changelog below.
===========================================
The Allwinner H616 contains an IOMMU almost compatible to the one used
in the H6. The differing default reset value of the bypass register
makes the two technically incompatible, so use a new DT compatible
string to be on the safe side.
The required driver changes can be applied to both variants, so the driver
is ignorant of the differences between the two for now.
Change the driver to cope with the new variant in patch 1/5 and 2/5,
then apply the required devicetree and binding changes in the remaining
patches.
I could just verify that the driver probes and allocates the page table
from below 4 GB. Others have verified that the driver works with the
(not yet upstream) video decoder engine, but more tests are surely
welcome.
Cheers,
Andre.
Changelog v1 .. v2:
- return error for too large PA in map_pages()
- add Krzysztof's ACK to the binding patch
Andre Przywara (4):
iommu: sun50i: allocate page tables from below 4 GiB
dt-bindings: iommu: add new compatible strings
iommu: sun50i: Add H616 compatible string
arm64: dts: allwinner: h616: add IOMMU node
Jernej Skrabec (1):
iommu: sun50i: clear bypass register
.../bindings/iommu/allwinner,sun50i-h6-iommu.yaml | 7 ++++++-
arch/arm64/boot/dts/allwinner/sun50i-h616.dtsi | 9 +++++++++
drivers/iommu/sun50i-iommu.c | 15 +++++++++++++--
3 files changed, 28 insertions(+), 3 deletions(-)
--
2.39.4
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