On 2026-07-01 11:12 a.m., Matt Evans wrote:>
> PCI POWER CONTROL
> diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
> index 33c88432b728..59d70bc84cc9 100644
> --- a/drivers/pci/Kconfig
> +++ b/drivers/pci/Kconfig
> @@ -206,11 +206,7 @@ config PCIE_TPH
> config PCI_P2PDMA
> bool "PCI peer-to-peer transfer support"
> depends on ZONE_DEVICE
> - #
> - # The need for the scatterlist DMA bus address flag means PCI P2PDMA
> - # requires 64bit
> - #
> - depends on 64BIT
> + select PCI_P2PDMA_CORE
Can we remove this dependency on 64BIT? Althogh it looks like
af2880ec440 complicated the issue a bit.
If I remember correctly, the original reason for this is because on
64bit systems dma_flags fit into unusued space in struct scatterlist and
on 32bit systems this space didn't exist and thus adding the flag
required increasing the size of the structure which wasn't desirable at
the time.
But af2880ec440 introduced CONFIG_NEED_SG_DMA_FLAGS which doesn't depend
on 64bit which means if CONFIG_IOMMU_DMA and CONFIG_SWIOTLB are now set
on 32bit systems that structure will grow quite a bit.
So maybe at this point it's fine to enable this on 32bit systems and we
can remove this requirement. However, I think we should do that
explicitly in its own patch, not hide it in this refactoring patch.
Logan
