PCI: Vulcan: AHCI PCI bar fix for Broadcom Vulcan early silicon

PCI BAR 5 is not setup correctly for the on-board AHCI
controller on Broadcom's Vulcan processor. Added a quirk to fix BAR 5
by using BAR 4's resources which are populated correctly but NOT used
by the AHCI controller actually.

Signed-off-by: Ashok Kumar Sekar <asekar@redhat.com>
Signed-off-by: Jayachandran C <jchandra@broadcom.com>

drivers/pci/quirks.c

@@ -4013,6 +4013,30 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_BROADCOM, 0x9000,
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_BROADCOM, 0x9084,
 				quirk_bridge_cavm_thrx2_pcie_root);
 
+/*
+ * PCI BAR 5 is not setup correctly for the on-board AHCI controller
+ * on Broadcom's Vulcan processor. Added a quirk to fix BAR 5 by
+ * using BAR 4's resources which are populated correctly and NOT
+ * actually used by the AHCI controller.
+ */
+static void quirk_fix_vulcan_ahci_bars(struct pci_dev *dev)
+{
+	struct resource *r =  &dev->resource[4];
+
+	if (!(r->flags & IORESOURCE_MEM) || (r->start == 0))
+		return;
+
+	/* Set BAR5 resource to BAR4 */
+	dev->resource[5] = *r;
+
+	/* Update BAR5 in pci config space */
+	pci_write_config_dword(dev, PCI_BASE_ADDRESS_5, r->start);
+
+	/* Clear BAR4's resource */
+	memset(r, 0, sizeof(*r));
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_BROADCOM, 0x9027, quirk_fix_vulcan_ahci_bars);
+
 /*
  * Intersil/Techwell TW686[4589]-based video capture cards have an empty (zero)
  * class code.  Fix it.