[PATCH v2 0/3] iommu: rockchip: Fix discovery table address encoding

Jonas Karlman jonas at kwiboo.se
Thu Jun 15 13:10:45 PDT 2023


This is a re-send of a series sent out in January, see [1].

The address to the discovery table is currently encoded using an
incorrect bit layout when configured into the MMU_DTE_ADDR reg.

This currently do not cause any issue because the discovery and page
tables is allocated in memory below 4GB thanks to the GFP_DMA32 flag.

Testing has shown that the discovery table address should be encoded
using the same bit layout as the page table and memory page addresses.

Removing the GFP_DMA32 on a RK3568 with 8GB of memory will result in:

[    0.907236] rk_iommu fe043e00.iommu: Page fault at 0x00000000ff801000 of type read
[    0.907264] rk_iommu fe043e00.iommu: iova = 0x00000000ff801000: dte_index: 0x3fe pte_index: 0x1 page_offset: 0x0
[    0.907281] rk_iommu fe043e00.iommu: mmu_dte_addr: 0x000000010189a000 dte at 0x000000010189aff8: 0x1722101 valid: 1 pte at 0x0000000101722004: 0x2c01107 valid: 1 page at 0x0000000102c01000 flags: 0x106

This series fixes this by using the existing mk_dtentries instead of the
dma_addr_dte ops to encode the discovery table address, removes unused
ops and finally removes the GFP_DMA32 flag to allow for discovery and
page tables to be allocated in memory above 4GB.

Changes in v2:
- no changes, rebased on next-20230615

This series can also be found at [2].

[1] https://lore.kernel.org/all/20230125221809.3275481-1-jonas@kwiboo.se/
[2] https://github.com/Kwiboo/linux-rockchip/commits/next-20230615-iommu

Jonas Karlman (3):
  iommu: rockchip: Fix discovery table address encoding
  iommu: rockchip: Remove unused variant ops
  iommu: rockchip: Allocate tables from all available memory

 drivers/iommu/rockchip-iommu.c | 45 +++++-----------------------------
 1 file changed, 6 insertions(+), 39 deletions(-)

-- 
2.40.1




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