From 0a8f41023e8a3c100b3dc458ed2da651bf961ead Mon Sep 17 00:00:00 2001
From: Bjorn Helgaas <bhelgaas@google.com>
Date: Thu, 9 Apr 2020 12:43:45 -0500
Subject: PCI: Move Apex Edge TPU class quirk to fix BAR assignment
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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>
---
drivers/pci/quirks.c | 7 +++++++
1 file changed, 7 insertions(+)
(limited to 'drivers/pci/quirks.c')
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);
--
cgit