ARM: cns3xxx: Use actual size reads for PCIe

Koen Vandeputte · bjorn-helgaas · commit 432dd7064aa1 · 2019-01-31T15:07:16.000-06:00
commit 802b7c0 ("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: 802b7c0 ("ARM: cns3xxx: Convert PCI to use generic config accessors") Suggested-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Koen Vandeputte <koen.vandeputte@ncentric.com> [lorenzo.pieralisi@arm.com: updated commit log] Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Krzysztof Halasa <khalasa@piap.pl> Acked-by: Arnd Bergmann <arnd@arndb.de> CC: Krzysztof Halasa <khalasa@piap.pl> CC: Olof Johansson <olof@lixom.net> CC: Robin Leblon <robin.leblon@ncentric.com> CC: Rob Herring <robh@kernel.org> CC: Russell King <linux@armlinux.org.uk> CC: Tim Harvey <tharvey@gateworks.com>
diff --git 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)
