PCI: Move Apex Edge TPU class quirk to fix BAR assignment

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@mail.gmail.com
Fixes: f390d08d8b87 ("staging: gasket: apex: fixup undefined PCI class")
Reported-by: Luís Mendes <luis.p.mendes@gmail.com>
Debugged-by: Luís Mendes <luis.p.mendes@gmail.com>
Tested-by: Luis Mendes <luis.p.mendes@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Todd Poynor <toddpoynor@google.com>

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 28c9a24..ca9ed57 100644 (file)
--- 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 46199c8..f12f81c 100644 (file)
--- 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)
 {