PCI: SR-IOV quirk for Intel 82576 NIC

If BIOS doesn't allocate resources for the SR-IOV BARs, zero the Flash
BAR and program the SR-IOV BARs to use the old Flash Memory Space.

Please refer to Intel 82576 Gigabit Ethernet Controller Datasheet
section 7.9.2.14.2 for details.
http://download.intel.com/design/network/datashts/82576_Datasheet.pdf

Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/quirks.c

@@ -2411,6 +2411,54 @@ DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x4375,
 
 #endif /* CONFIG_PCI_MSI */
 
+#ifdef CONFIG_PCI_IOV
+
+/*
+ * For Intel 82576 SR-IOV NIC, if BIOS doesn't allocate resources for the
+ * SR-IOV BARs, zero the Flash BAR and program the SR-IOV BARs to use the
+ * old Flash Memory Space.
+ */
+static void __devinit quirk_i82576_sriov(struct pci_dev *dev)
+{
+	int pos, flags;
+	u32 bar, start, size;
+
+	if (PAGE_SIZE > 0x10000)
+		return;
+
+	flags = pci_resource_flags(dev, 0);
+	if ((flags & PCI_BASE_ADDRESS_SPACE) !=
+			PCI_BASE_ADDRESS_SPACE_MEMORY ||
+	    (flags & PCI_BASE_ADDRESS_MEM_TYPE_MASK) !=
+			PCI_BASE_ADDRESS_MEM_TYPE_32)
+		return;
+
+	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
+	if (!pos)
+		return;
+
+	pci_read_config_dword(dev, pos + PCI_SRIOV_BAR, &bar);
+	if (bar & PCI_BASE_ADDRESS_MEM_MASK)
+		return;
+
+	start = pci_resource_start(dev, 1);
+	size = pci_resource_len(dev, 1);
+	if (!start || size != 0x400000 || start & (size - 1))
+		return;
+
+	pci_resource_flags(dev, 1) = 0;
+	pci_write_config_dword(dev, PCI_BASE_ADDRESS_1, 0);
+	pci_write_config_dword(dev, pos + PCI_SRIOV_BAR, start);
+	pci_write_config_dword(dev, pos + PCI_SRIOV_BAR + 12, start + size / 2);
+
+	dev_info(&dev->dev, "use Flash Memory Space for SR-IOV BARs\n");
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x10c9, quirk_i82576_sriov);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x10e6, quirk_i82576_sriov);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x10e7, quirk_i82576_sriov);
+
+#endif	/* CONFIG_PCI_IOV */
+
 static void pci_do_fixups(struct pci_dev *dev, struct pci_fixup *f,
 			  struct pci_fixup *end)
 {