When reading 8 or 16 bits from config space, use appropriate readb() or readw() calls. This ensures that PCIe controller does not read more bits from endpoint card as asked by read_config() function.
Technically there should not be an issue with reading data from config space which are not later used as there are no clear-by-read registers. But it is better to use correct read operation based on requested size.
Signed-off-by: Pali Rohár pali@kernel.org Reviewed-by: Marek Behún marek.behun@nic.cz --- drivers/pci/pci_mvebu.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/pci_mvebu.c b/drivers/pci/pci_mvebu.c index 8175511514ab..3991086e0d29 100644 --- a/drivers/pci/pci_mvebu.c +++ b/drivers/pci/pci_mvebu.c @@ -184,9 +184,22 @@ static int mvebu_pcie_read_config(const struct udevice *bus, pci_dev_t bdf, writel(PCIE_CONF_ADDR(bdf, offset), pcie->base + PCIE_CONF_ADDR_OFF);
/* read data */ - data = readl(pcie->base + PCIE_CONF_DATA_OFF); + switch (size) { + case PCI_SIZE_8: + data = readb(pcie->base + PCIE_CONF_DATA_OFF + (offset & 3)); + break; + case PCI_SIZE_16: + data = readw(pcie->base + PCIE_CONF_DATA_OFF + (offset & 2)); + break; + case PCI_SIZE_32: + data = readl(pcie->base + PCIE_CONF_DATA_OFF); + break; + default: + return -EINVAL; + } + debug("(addr,size,val)=(0x%04x, %d, 0x%08x)\n", offset, size, data); - *valuep = pci_conv_32_to_size(data, offset, size); + *valuep = data;
return 0; }