If there is a DT node available for the root bridge's parent device, use
the DMA configuration from that device node. For example, Keystone PCI
devices would require dma_pfn_offset to be set correctly in the device
structure of the PCI device in order to have the correct DMA mask. The DT
node will have dma-ranges defined for this. Also support using the DT
property dma-coherent to allow coherent DMA operation by the PCI device.
Use the new helper function of_pci_dma_configure() to update the device DMA
configuration. This fixes DMA on systems where DMA addresses are a
constant offset from CPU physical addresses.
Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> (AMD Seattle) Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> CC: Joerg Roedel <joro@8bytes.org> CC: Grant Likely <grant.likely@linaro.org> CC: Rob Herring <robh+dt@kernel.org> CC: Russell King <linux@arm.linux.org.uk> CC: Arnd Bergmann <arnd@arndb.de>