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
