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7bea67a994
A recent change affecting the behaviour of phys_to_dma() to
actually require the device tree ranges to work unmasked a
bug in the Integrator DMA ranges.
The PL110 uses the CMA allocator to obtain coherent allocations
from a dedicated 1MB video memory, leading to the following
call chain:
drm_gem_cma_create()
dma_alloc_attrs()
dma_alloc_from_dev_coherent()
__dma_alloc_from_coherent()
dma_get_device_base()
phys_to_dma()
translate_phys_to_dma()
phys_to_dma() by way of translate_phys_to_dma() will nowadays not
provide 1:1 mappings unless the ranges are properly defined in
the device tree and reflected into the dev->dma_range_map.
There is a bug in the device trees because the DMA ranges are
incorrectly specified, and the patch uncovers this bug.
Solution:
- Fix the LB (logic bus) ranges to be 1-to-1 like they should
have always been.
- Provide a 1:1 dma-ranges attribute to the PL110.
- Mark the PL110 display controller as DMA coherent.
This makes the DMA ranges work right and makes the PL110
framebuffer work again.
Fixes: af6f23b88e ("ARM/dma-mapping: use the generic versions of dma_to_phys/phys_to_dma by default")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220926073311.1610568-1-linus.walleij@linaro.org'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Linux kernel
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