| Message ID | 1595065176-460-1-git-send-email-yangtiezhu@loongson.cn (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | 64d293d8ac878a31cd009f3f1ae8aa71d55d2389 |
| Headers | show |
| Series | [v5] PCI: loongson: Use DECLARE_PCI_FIXUP_EARLY for bridge_class_quirk() | expand |
On Sat, Jul 18, 2020 at 05:39:36PM +0800, Tiezhu Yang wrote: > 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. As far > as I know, the latest version of LS7A has already fixed the value at the > hardware level. > > 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. > > 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 > > v4: Update the commit message to describe the bug > > v5: Remove "due to" in the commit message suggested by Sergei Shtylyov > > drivers/pci/controller/pci-loongson.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) Applied to pci/loongson, thanks. Lorenzo > 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 >
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)
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. As far as I know, the latest version of LS7A has already fixed the value at the hardware level. 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. 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 v4: Update the commit message to describe the bug v5: Remove "due to" in the commit message suggested by Sergei Shtylyov drivers/pci/controller/pci-loongson.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)