Using write-combine is crucial for performance of PCI devices where significant amounts of transactions go over PCI BARs. arm64 supports write-combine PCI mappings, so the appropriate define has been added which will expose write-combine mappings under sysfs for prefetchable PCI resources. Signed-off-by: Clint Sbisa <csbisa@xxxxxxxxxx> --- arch/arm64/include/asm/pci.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/include/asm/pci.h b/arch/arm64/include/asm/pci.h index 70b323cf8300..b33ca260e3c9 100644 --- a/arch/arm64/include/asm/pci.h +++ b/arch/arm64/include/asm/pci.h @@ -17,6 +17,7 @@ #define pcibios_assign_all_busses() \ (pci_has_flag(PCI_REASSIGN_ALL_BUS)) +#define arch_can_pci_mmap_wc() 1 #define ARCH_GENERIC_PCI_MMAP_RESOURCE 1 extern int isa_dma_bridge_buggy; -- 2.23.3
