Re: [PATCH v4] PCI: loongson: Use DECLARE_PCI_FIXUP_EARLY for bridge_class_quirk()

[Sergei Shtylyov]

On 18.07.2020 11:37, 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 due to without

   "Due to" not needed there.

> EARLY fixup.
>
> Fixes: 1f58cca5cf2b ("PCI: Add Loongson PCI Controller support")
> Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
[...]

MBR, Sergei