4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Koen Vandeputte <[email protected]> commit 65dbb423cf28232fed1732b779249d6164c5999b upstream. Originally, cns3xxx used its own functions for mapping, reading and writing config registers. Commit 802b7c06adc7 ("ARM: cns3xxx: Convert PCI to use generic config accessors") removed the internal PCI config write function in favor of the generic one: cns3xxx_pci_write_config() --> pci_generic_config_write() cns3xxx_pci_write_config() expected aligned addresses, being produced by cns3xxx_pci_map_bus() while the generic one pci_generic_config_write() actually expects the real address as both the function and hardware are capable of byte-aligned writes. This currently leads to pci_generic_config_write() writing to the wrong registers. For instance, upon ath9k module loading: - driver ath9k gets loaded - The driver wants to write value 0xA8 to register PCI_LATENCY_TIMER, located at 0x0D - cns3xxx_pci_map_bus() aligns the address to 0x0C - pci_generic_config_write() effectively writes 0xA8 into register 0x0C (CACHE_LINE_SIZE) Fix the bug by removing the alignment in the cns3xxx mapping function. Fixes: 802b7c06adc7 ("ARM: cns3xxx: Convert PCI to use generic config accessors") Signed-off-by: Koen Vandeputte <[email protected]> [[email protected]: updated commit log] Signed-off-by: Lorenzo Pieralisi <[email protected]> Acked-by: Krzysztof Halasa <[email protected]> Acked-by: Tim Harvey <[email protected]> Acked-by: Arnd Bergmann <[email protected]> CC: [email protected] # v4.0+ CC: Bjorn Helgaas <[email protected]> CC: Olof Johansson <[email protected]> CC: Robin Leblon <[email protected]> CC: Rob Herring <[email protected]> CC: Russell King <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/arm/mach-cns3xxx/pcie.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/arm/mach-cns3xxx/pcie.c +++ b/arch/arm/mach-cns3xxx/pcie.c @@ -83,7 +83,7 @@ static void __iomem *cns3xxx_pci_map_bus } else /* remote PCI bus */ base = cnspci->cfg1_regs + ((busno & 0xf) << 20); - return base + (where & 0xffc) + (devfn << 12); + return base + where + (devfn << 12); } static int cns3xxx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
