Merge branch 'pci/resource'

- Always write Intel I210 ROM BAR on update to work around device defect
  (Bjorn Helgaas)

* pci/resource:
  PCI: Work around Intel I210 ROM BAR overlap defect

Author: bjorn-helgaas

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);

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;
 

include/linux/pci.h

@@ -455,6 +455,7 @@ struct pci_dev {
 	unsigned int	link_active_reporting:1;/* Device capable of reporting link active */
 	unsigned int	no_vf_scan:1;		/* Don't scan for VFs after IOV enablement */
 	unsigned int	no_command_memory:1;	/* No PCI_COMMAND_MEMORY */
+	unsigned int	rom_bar_overlap:1;	/* ROM BAR disable broken */
 	pci_dev_flags_t dev_flags;
 	atomic_t	enable_cnt;	/* pci_enable_device has been called */