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    SubjectRe: [PATCH v3] PCI: loongson: Use DECLARE_PCI_FIXUP_EARLY for bridge_class_quirk()
    Hi, Tiezhu,

    You don't need to use the lower case in the title, "Loongson" is just
    fine (and is recommended).

    On Thu, Jul 16, 2020 at 10:19 AM Tiezhu Yang <yangtiezhu@loongson.cn> wrote:
    >
    > According to the datasheet of Loongson LS7A bridge chip, the old version
    > of Loongson LS7A PCIE port has a hardware bug about PCI class. As far as
    > I know, the latest version has already fixed this bug.
    >
    > 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 due to without
    > EARLY fixup.
    >
    > By the way, we can see that the PCI class fixup of other controllers are
    > all EARLY fixups:
    >
    > [root@linux linux.git]# grep -rn -A 3 "PCI_CLASS_BRIDGE_PCI << 8" drivers/pci/controller/ | grep EARLY
    > drivers/pci/controller/pcie-tango.c-327-DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SIGMA, 0x0024, tango_fixup_class);
    > drivers/pci/controller/pcie-tango.c-328-DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SIGMA, 0x0028, tango_fixup_class);
    > drivers/pci/controller/pci-tegra.c-775-DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, 0x0bf0, tegra_pcie_fixup_class);
    > drivers/pci/controller/pci-tegra.c-776-DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, 0x0bf1, tegra_pcie_fixup_class);
    > drivers/pci/controller/dwc/pcie-qcom.c-1442-DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_QCOM, 0x0101, qcom_fixup_class);
    > drivers/pci/controller/dwc/pcie-qcom.c-1443-DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_QCOM, 0x0104, qcom_fixup_class);
    > drivers/pci/controller/pcie-iproc-bcma.c-23-DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_BROADCOM, 0x8011, bcma_pcie2_fixup_class);
    > drivers/pci/controller/pcie-iproc-bcma.c-24-DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_BROADCOM, 0x8012, bcma_pcie2_fixup_class);
    >
    > Fixes: 1f58cca5cf2b ("PCI: Add Loongson PCI Controller support")
    > Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
    > ---
    >
    > v2: Modify the patch subject used with lower case "loongson"
    >
    > v3: Update the commit message
    >
    > 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 459009c..58b862a 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)
    > --
    > 2.1.0
    >

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