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authorBjorn Helgaas <bhelgaas@google.com>2021-12-21 10:45:07 -0600
committerBjorn Helgaas <bhelgaas@google.com>2022-01-11 09:33:10 -0600
commit500b55b05d0a21c4adddf4c3b29ee6f32b502046 (patch)
treefb08ffe79a38b7948798745fb5336849368a3432 /drivers/pci
parentfa55b7dcdc43c1aa1ba12bca9d2dd4318c2a0dbf (diff)
PCI: Work around Intel I210 ROM BAR overlap defect
Per PCIe r5, sec 7.5.1.2.4, a device must not claim accesses to its Expansion ROM unless both the Memory Space Enable and the Expansion ROM Enable bit are set. But apparently some Intel I210 NICs don't work correctly if the ROM BAR overlaps another BAR, even if the Expansion ROM is disabled. Michael reported that on a Kontron SMARC-sAL28 ARM64 system with U-Boot v2021.01-rc3, the ROM BAR overlaps BAR 3, and networking doesn't work at all: BAR 0: 0x40000000 (32-bit, non-prefetchable) [size=1M] BAR 3: 0x40200000 (32-bit, non-prefetchable) [size=16K] ROM: 0x40200000 (disabled) [size=1M] NETDEV WATCHDOG: enP2p1s0 (igb): transmit queue 0 timed out Hardware name: Kontron SMARC-sAL28 (Single PHY) on SMARC Eval 2.0 carrier (DT) igb 0002:01:00.0 enP2p1s0: Reset adapter Previously, pci_std_update_resource() wrote the assigned ROM address to the BAR only when the ROM was enabled. This meant that the I210 ROM BAR could be left with an address assigned by firmware, which might overlap with other BARs. Quirk these I210 devices so pci_std_update_resource() always writes the assigned address to the ROM BAR, whether or not the ROM is enabled. Link: https://lore.kernel.org/r/20211223163754.GA1267351@bhelgaas Link: https://lore.kernel.org/r/20201230185317.30915-1-michael@walle.cc Link: https://bugzilla.kernel.org/show_bug.cgi?id=211105 Reported-by: Michael Walle <michael@walle.cc> Tested-by: Michael Walle <michael@walle.cc> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/quirks.c10
-rw-r--r--drivers/pci/setup-res.c8
2 files changed, 16 insertions, 2 deletions
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 003950c738d2..46ff04091fa3 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -5857,3 +5857,13 @@ static void nvidia_ion_ahci_fixup(struct pci_dev *pdev)
pdev->dev_flags |= PCI_DEV_FLAGS_HAS_MSI_MASKING;
}
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, 0x0ab8, nvidia_ion_ahci_fixup);
+
+static void rom_bar_overlap_defect(struct pci_dev *dev)
+{
+ pci_info(dev, "working around ROM BAR overlap defect\n");
+ dev->rom_bar_overlap = 1;
+}
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1533, rom_bar_overlap_defect);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1536, rom_bar_overlap_defect);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1537, rom_bar_overlap_defect);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1538, rom_bar_overlap_defect);
diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
index 7f1acb3918d0..439ac5f5907a 100644
--- a/drivers/pci/setup-res.c
+++ b/drivers/pci/setup-res.c
@@ -75,12 +75,16 @@ static void pci_std_update_resource(struct pci_dev *dev, int resno)
* as zero when disabled, so don't update ROM BARs unless
* they're enabled. See
* https://lore.kernel.org/r/43147B3D.1030309@vc.cvut.cz/
+ * But we must update ROM BAR for buggy devices where even a
+ * disabled ROM can conflict with other BARs.
*/
- if (!(res->flags & IORESOURCE_ROM_ENABLE))
+ if (!(res->flags & IORESOURCE_ROM_ENABLE) &&
+ !dev->rom_bar_overlap)
return;
reg = dev->rom_base_reg;
- new |= PCI_ROM_ADDRESS_ENABLE;
+ if (res->flags & IORESOURCE_ROM_ENABLE)
+ new |= PCI_ROM_ADDRESS_ENABLE;
} else
return;