Commit b38034b5 authored by Will McVicker's avatar Will McVicker Committed by Treehugger Robot
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BACKPORT: FROMLIST: PCI: dwc: Add support for 64-bit MSI target address

Since not all devices require a 32-bit MSI address, add support to the
PCIe host driver to allow setting the DMA mask to 64-bits. This allows
kernels to disable ZONE_DMA32 and bounce buffering (swiotlb) without
risking not being able to get a 32-bit address during DMA allocation.
Basically, in the slim chance that there are no 32-bit allocations
available, the current PCIe host driver will fail to allocate the
msi_msg page due to a DMA address overflow (seen in [1]). With this
patch, the PCIe device can advertise 64-bit support via its MSI
capabilities to hint to the PCIe host driver to set the DMA mask to
64-bits.

[1] https://lore.kernel.org/all/Yo0soniFborDl7+C@google.com/

Link: https://lore.kernel.org/all/20220812000327.3154251-3-willmcvicker@google.com/


Bug: 241473543
Reported-by: default avatarkernel test robot <lkp@intel.com>
Signed-off-by: default avatarWill McVicker <willmcvicker@google.com>
Reviewed-by: default avatarRob Herring <robh@kernel.org>
Acked-by: default avatarJingoo Han <jingoohan1@gmail.com>
Change-Id: I23276717dd6fdf8b3e5adb2d6a706a8378f9c6bb
parent 6c982872
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