From a264b5e8dc3cae1b07cea010d6283be6e67b0209 Mon Sep 17 00:00:00 2001 From: Jayachandran C Date: Wed, 16 Jan 2013 11:12:40 +0000 Subject: [PATCH] MIPS: PCI: Byteswap not needed in little-endian mode Rename function xlp_enable_pci_bswap() to xlp_config_pci_bswap(), which is a better description for its functionality. When compiled in big-endian mode, xlp_config_pci_bswap() will configure the PCIe links to byteswap. In little-endian mode, no swap configuration is needed for the PCIe controller, and the function is empty. Signed-off-by: Jayachandran C Patchwork: http://patchwork.linux-mips.org/patch/4802/ Signed-off-by: John Crispin --- arch/mips/pci/pci-xlp.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/arch/mips/pci/pci-xlp.c b/arch/mips/pci/pci-xlp.c index 140557a20488..5077148bd67d 100644 --- a/arch/mips/pci/pci-xlp.c +++ b/arch/mips/pci/pci-xlp.c @@ -191,7 +191,13 @@ int pcibios_plat_dev_init(struct pci_dev *dev) return 0; } -static int xlp_enable_pci_bswap(void) +/* + * If big-endian, enable hardware byteswap on the PCIe bridges. + * This will make both the SoC and PCIe devices behave consistently with + * readl/writel. + */ +#ifdef __BIG_ENDIAN +static void xlp_config_pci_bswap(void) { uint64_t pciebase, sysbase; int node, i; @@ -222,8 +228,11 @@ static int xlp_enable_pci_bswap(void) reg = nlm_read_bridge_reg(sysbase, BRIDGE_PCIEIO_LIMIT0 + i); nlm_write_pci_reg(pciebase, PCIE_BYTE_SWAP_IO_LIM, reg | 0xfff); } - return 0; } +#else +/* Swap configuration not needed in little-endian mode */ +static inline void xlp_config_pci_bswap(void) {} +#endif /* __BIG_ENDIAN */ static int __init pcibios_init(void) { @@ -235,7 +244,7 @@ static int __init pcibios_init(void) ioport_resource.start = 0; ioport_resource.end = ~0; - xlp_enable_pci_bswap(); + xlp_config_pci_bswap(); set_io_port_base(CKSEG1); nlm_pci_controller.io_map_base = CKSEG1; -- 2.20.1