From c003ca99632e1783466f459033874a0e1e31457b Mon Sep 17 00:00:00 2001 From: Gabriele Paoloni Date: Thu, 8 Oct 2015 14:27:43 -0500 Subject: [PATCH] PCI: designware: Use exact access size in dw_pcie_cfg_read() dw_pcie_cfg_write() uses the exact 8-, 16-, or 32-bit access size requested, but dw_pcie_cfg_read() previously performed a 32-bit read and masked out the bits requested. Use the exact access size in dw_pcie_cfg_read(). For example, if we want an 8-bit read, use readb() instead of using readl() and masking out the 8 bits we need. This makes it symmetric with dw_pcie_cfg_write(). [bhelgaas: split into separate patch, set *val = 0 in failure case] Signed-off-by: Gabriele Paoloni Signed-off-by: Bjorn Helgaas --- drivers/pci/host/pcie-designware.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c index 0085748ba5e4..451f01e145c2 100644 --- a/drivers/pci/host/pcie-designware.c +++ b/drivers/pci/host/pcie-designware.c @@ -82,14 +82,16 @@ static inline struct pcie_port *sys_to_pcie(struct pci_sys_data *sys) int dw_pcie_cfg_read(void __iomem *addr, int where, int size, u32 *val) { - *val = readl(addr); - - if (size == 1) - *val = (*val >> (8 * (where & 3))) & 0xff; + if (size == 4) + *val = readl(addr); else if (size == 2) - *val = (*val >> (8 * (where & 3))) & 0xffff; - else if (size != 4) + *val = readw(addr + (where & 2)); + else if (size == 1) + *val = readb(addr + (where & 1)); + else { + *val = 0; return PCIBIOS_BAD_REGISTER_NUMBER; + } return PCIBIOS_SUCCESSFUL; } -- 2.20.1