From 65dbb423cf28232fed1732b779249d6164c5999b Mon Sep 17 00:00:00 2001 From: Koen Vandeputte Date: Thu, 31 Jan 2019 15:00:01 -0600 Subject: ARM: cns3xxx: Fix writing to wrong PCI config registers after alignment 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 [lorenzo.pieralisi@arm.com: updated commit log] Signed-off-by: Lorenzo Pieralisi Acked-by: Krzysztof Halasa Acked-by: Tim Harvey Acked-by: Arnd Bergmann CC: stable@vger.kernel.org # v4.0+ CC: Bjorn Helgaas CC: Olof Johansson CC: Robin Leblon CC: Rob Herring CC: Russell King --- arch/arm/mach-cns3xxx/pcie.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/arm/mach-cns3xxx/pcie.c b/arch/arm/mach-cns3xxx/pcie.c index 318394ed5c7a..5e11ad3164e0 100644 --- 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(struct pci_bus *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, -- cgit v1.2.3 From 432dd7064aa1c030a488745917cfa4ebc6c8c060 Mon Sep 17 00:00:00 2001 From: Koen Vandeputte Date: Thu, 31 Jan 2019 15:00:11 -0600 Subject: ARM: cns3xxx: Use actual size reads for PCIe commit 802b7c06adc7 ("ARM: cns3xxx: Convert PCI to use generic config accessors") reimplemented cns3xxx_pci_read_config() using pci_generic_config_read32(), which preserved the property of only doing 32-bit reads. It also replaced cns3xxx_pci_write_config() with pci_generic_config_write(), so it changed writes from always being 32 bits to being the actual size, which works just fine. Given that: - The documentation does not mention that only 32 bit access is allowed. - Writes are already executed using the actual size - Extensive testing shows that 8b, 16b and 32b reads work as intended Allow read access of any size by replacing pci_generic_config_read32() with the pci_generic_config_read() accessors. Fixes: 802b7c06adc7 ("ARM: cns3xxx: Convert PCI to use generic config accessors") Suggested-by: Bjorn Helgaas Signed-off-by: Koen Vandeputte [lorenzo.pieralisi@arm.com: updated commit log] Signed-off-by: Lorenzo Pieralisi Acked-by: Krzysztof Halasa Acked-by: Arnd Bergmann CC: Krzysztof Halasa CC: Olof Johansson CC: Robin Leblon CC: Rob Herring CC: Russell King CC: Tim Harvey --- arch/arm/mach-cns3xxx/pcie.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/arm/mach-cns3xxx/pcie.c b/arch/arm/mach-cns3xxx/pcie.c index 5e11ad3164e0..95a11d5b3587 100644 --- a/arch/arm/mach-cns3xxx/pcie.c +++ b/arch/arm/mach-cns3xxx/pcie.c @@ -93,7 +93,7 @@ static int cns3xxx_pci_read_config(struct pci_bus *bus, unsigned int devfn, u32 mask = (0x1ull << (size * 8)) - 1; int shift = (where % 4) * 8; - ret = pci_generic_config_read32(bus, devfn, where, size, val); + ret = pci_generic_config_read(bus, devfn, where, size, val); if (ret == PCIBIOS_SUCCESSFUL && !bus->number && !devfn && (where & 0xffc) == PCI_CLASS_REVISION) -- cgit v1.2.3