PCI: save and restore PCIe 2.0 registers

PCIe 2.0 defines several new registers (Device Control 2, Link Control 2,
and Slot Control 2). Save and retore them in pci_save_pcie_state() and
pci_restore_pcie_state().
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/pci.c

@@ -647,6 +647,8 @@ pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
 
 EXPORT_SYMBOL(pci_choose_state);
 
+#define PCI_EXP_SAVE_REGS	7
+
 static int pci_save_pcie_state(struct pci_dev *dev)
 {
 	int pos, i = 0;
@@ -668,6 +670,9 @@ static int pci_save_pcie_state(struct pci_dev *dev)
 	pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
 	pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
 	pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
+	pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &cap[i++]);
+	pci_read_config_word(dev, pos + PCI_EXP_LNKCTL2, &cap[i++]);
+	pci_read_config_word(dev, pos + PCI_EXP_SLTCTL2, &cap[i++]);
 
 	return 0;
 }
@@ -688,6 +693,9 @@ static void pci_restore_pcie_state(struct pci_dev *dev)
 	pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
 	pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
 	pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
+	pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, cap[i++]);
+	pci_write_config_word(dev, pos + PCI_EXP_LNKCTL2, cap[i++]);
+	pci_write_config_word(dev, pos + PCI_EXP_SLTCTL2, cap[i++]);
 }
 
 
@@ -1372,7 +1380,8 @@ void pci_allocate_cap_save_buffers(struct pci_dev *dev)
 {
 	int error;
 
-	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP, 4 * sizeof(u16));
+	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
+					PCI_EXP_SAVE_REGS * sizeof(u16));
 	if (error)
 		dev_err(&dev->dev,
 			"unable to preallocate PCI Express save buffer\n");

include/linux/pci_regs.h

@@ -488,6 +488,8 @@
 #define  PCI_EXP_DEVCAP2_ARI	0x20	/* Alternative Routing-ID */
 #define PCI_EXP_DEVCTL2		40	/* Device Control 2 */
 #define  PCI_EXP_DEVCTL2_ARI	0x20	/* Alternative Routing-ID */
+#define PCI_EXP_LNKCTL2		48	/* Link Control 2 */
+#define PCI_EXP_SLTCTL2		56	/* Slot Control 2 */
 
 /* Extended Capabilities (PCI-X 2.0 and Express) */
 #define PCI_EXT_CAP_ID(header)		(header & 0x0000ffff)