From: Tiezhu Yang yangtiezhu@loongson.cn
[ Upstream commit 14110af606965ce07abe4d121c100241c2e73b86 ]
According to the datasheet of Loongson LS7A bridge chip, the old version of Loongson LS7A PCIE port has a wrong value about PCI class which is 0x060000, the correct value should be 0x060400, this bug can be fixed by "dev->class = PCI_CLASS_BRIDGE_PCI << 8;" at the software level and it was fixed in hardware in the latest LS7A versions.
In order to maintain downward compatibility, use DECLARE_PCI_FIXUP_EARLY instead of DECLARE_PCI_FIXUP_HEADER for bridge_class_quirk() to fix it as early as possible.
Otherwise, in the function pci_setup_device(), the related code about "dev->class" such as "class = dev->class >> 8;" and "dev->transparent = ((dev->class & 0xff) == 1);" maybe get wrong value without EARLY fixup.
Link: https://lore.kernel.org/r/1595065176-460-1-git-send-email-yangtiezhu@loongso... Fixes: 1f58cca5cf2b ("PCI: Add Loongson PCI Controller support") Signed-off-by: Tiezhu Yang yangtiezhu@loongson.cn Signed-off-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pci/controller/pci-loongson.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/pci/controller/pci-loongson.c b/drivers/pci/controller/pci-loongson.c index 459009c8a4a02..58b862aaa6e94 100644 --- a/drivers/pci/controller/pci-loongson.c +++ b/drivers/pci/controller/pci-loongson.c @@ -37,11 +37,11 @@ static void bridge_class_quirk(struct pci_dev *dev) { dev->class = PCI_CLASS_BRIDGE_PCI << 8; } -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LOONGSON, +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, DEV_PCIE_PORT_0, bridge_class_quirk); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LOONGSON, +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, DEV_PCIE_PORT_1, bridge_class_quirk); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LOONGSON, +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON, DEV_PCIE_PORT_2, bridge_class_quirk);
static void system_bus_quirk(struct pci_dev *pdev)