Port of a Linux commit c003ca99632e1783466f459033874a0e1e31457b 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 <[email protected]> Signed-off-by: Bjorn Helgaas <[email protected]> NOTE: Original Linux commit incorrectly handles the case of single byte read by doing else if (size == 1) *val = readb(addr + (where & 1)); instead of else if (size == 1) *val = readb(addr + (where & 3)); which would be symmetric with what's done in dw_pcie_cfg_write(). This was most likely overlooked since commit that follow change the signature of the function, remove 'where' as argument completely, inadvertenly fixing the problem. Signed-off-by: Andrey Smirnov <[email protected]> --- drivers/pci/pcie-designware.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/pci/pcie-designware.c b/drivers/pci/pcie-designware.c index 547d402a7..bda85c30e 100644 --- a/drivers/pci/pcie-designware.c +++ b/drivers/pci/pcie-designware.c @@ -76,14 +76,16 @@ static unsigned long global_io_offset; 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 & 3)); + else { + *val = 0; return PCIBIOS_BAD_REGISTER_NUMBER; + } return PCIBIOS_SUCCESSFUL; } -- 2.19.1 _______________________________________________ barebox mailing list [email protected] http://lists.infradead.org/mailman/listinfo/barebox
