On Tue, Apr 14, 2020 at 07:17:53PM -0500, Bjorn Helgaas wrote:
> From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
>
> Some Google Apex Edge TPU devices have a class code of 0
> (PCI_CLASS_NOT_DEFINED). This prevents the PCI core from assigning
> resources for the Apex BARs because __dev_sort_resources() ignores
> classless devices, host bridges, and IOAPICs.
>
> On x86, firmware typically assigns those resources, so this was not a
> problem. But on some architectures, firmware does *not* assign BARs, and
> since the PCI core didn't do it either, the Apex device didn't work
> correctly:
>
> apex 0000:01:00.0: can't enable device: BAR 0 [mem 0x00000000-0x00003fff 64bit pref] not claimed
> apex 0000:01:00.0: error enabling PCI device
>
> f390d08d8b87 ("staging: gasket: apex: fixup undefined PCI class") added a
> quirk to fix the class code, but it was in the apex driver, and if the
> driver was built as a module, it was too late to help.
>
> Move the quirk to the PCI core, where it will always run early enough that
> the PCI core will assign resources if necessary.
>
> Link: https://lore.kernel.org/r/CAEzXK1r0Er039iERnc2KJ4jn7ySNUOG9H=Ha8TD8XroVqiZjgg@xxxxxxxxxxxxxx
> Fixes: f390d08d8b87 ("staging: gasket: apex: fixup undefined PCI class")
> Reported-by: Luís Mendes <luis.p.mendes@xxxxxxxxx>
> Debugged-by: Luís Mendes <luis.p.mendes@xxxxxxxxx>
> Tested-by: Luis Mendes <luis.p.mendes@xxxxxxxxx>
> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Cc: Todd Poynor <toddpoynor@xxxxxxxxxx>
Applied to for-linus for v5.7.
> ---
> drivers/pci/quirks.c | 7 +++++++
> drivers/staging/gasket/apex_driver.c | 7 -------
> 2 files changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index 28c9a2409c50..ca9ed5774eb1 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -5567,3 +5567,10 @@ static void pci_fixup_no_d0_pme(struct pci_dev *dev)
> dev->pme_support &= ~(PCI_PM_CAP_PME_D0 >> PCI_PM_CAP_PME_SHIFT);
> }
> DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ASMEDIA, 0x2142, pci_fixup_no_d0_pme);
> +
> +static void apex_pci_fixup_class(struct pci_dev *pdev)
> +{
> + pdev->class = (PCI_CLASS_SYSTEM_OTHER << 8) | pdev->class;
> +}
> +DECLARE_PCI_FIXUP_CLASS_HEADER(0x1ac1, 0x089a,
> + PCI_CLASS_NOT_DEFINED, 8, apex_pci_fixup_class);
> diff --git a/drivers/staging/gasket/apex_driver.c b/drivers/staging/gasket/apex_driver.c
> index 46199c8ca441..f12f81c8dd2f 100644
> --- a/drivers/staging/gasket/apex_driver.c
> +++ b/drivers/staging/gasket/apex_driver.c
> @@ -570,13 +570,6 @@ static const struct pci_device_id apex_pci_ids[] = {
> { PCI_DEVICE(APEX_PCI_VENDOR_ID, APEX_PCI_DEVICE_ID) }, { 0 }
> };
>
> -static void apex_pci_fixup_class(struct pci_dev *pdev)
> -{
> - pdev->class = (PCI_CLASS_SYSTEM_OTHER << 8) | pdev->class;
> -}
> -DECLARE_PCI_FIXUP_CLASS_HEADER(APEX_PCI_VENDOR_ID, APEX_PCI_DEVICE_ID,
> - PCI_CLASS_NOT_DEFINED, 8, apex_pci_fixup_class);
> -
> static int apex_pci_probe(struct pci_dev *pci_dev,
> const struct pci_device_id *id)
> {
> --
> 2.26.0.110.g2183baf09c-goog
>
