Re: [RFC PATCH v1] PCI: qcom: Use quirk to override incorrect device class
From: Marc Gonzalez
Date: Tue Mar 12 2019 - 13:35:21 EST
On 12/03/2019 18:18, Marc Gonzalez wrote:
> On 12/03/2019 13:42, Stanimir Varbanov wrote:
>
>> I wonder, in case that dw_pcie_setup_rc() already has a write to
>> PCI_CLASS_DEVICE configuration register to set it as a bridge do we
>> still need to do the above fixup?
>
> I don't know, I don't have an affected device. Unless the msm8998 /is/ affected,
> and dw_pcie_setup_rc() actually fixes it?
I think you hit the nail on the head...
If I comment out
//dw_pcie_wr_own_conf(pp, PCI_CLASS_DEVICE, 2, PCI_CLASS_BRIDGE_PCI);
from dw_pcie_setup_rc()
then pci_class() returns 0xff000000 instead of 0x6040000
So perhaps you're right: the quirk can be omitted altogether.
Unless it is not possible to program the device class on older chips?
Regards.