PCI/AER: Use PCI Express Capability accessors

Use PCI Express Capability access functions to simplify PCIe AER.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/pcie/aer/aerdrv.c

@@ -122,19 +122,17 @@ static void set_downstream_devices_error_reporting(struct pci_dev *dev,
 static void aer_enable_rootport(struct aer_rpc *rpc)
 {
 	struct pci_dev *pdev = rpc->rpd->port;
-	int pos, aer_pos;
+	int aer_pos;
 	u16 reg16;
 	u32 reg32;
 
-	pos = pci_pcie_cap(pdev);
 	/* Clear PCIe Capability's Device Status */
-	pci_read_config_word(pdev, pos+PCI_EXP_DEVSTA, &reg16);
-	pci_write_config_word(pdev, pos+PCI_EXP_DEVSTA, reg16);
+	pcie_capability_read_word(pdev, PCI_EXP_DEVSTA, &reg16);
+	pcie_capability_write_word(pdev, PCI_EXP_DEVSTA, reg16);
 
 	/* Disable system error generation in response to error messages */
-	pci_read_config_word(pdev, pos + PCI_EXP_RTCTL, &reg16);
-	reg16 &= ~(SYSTEM_ERROR_INTR_ON_MESG_MASK);
-	pci_write_config_word(pdev, pos + PCI_EXP_RTCTL, reg16);
+	pcie_capability_clear_word(pdev, PCI_EXP_RTCTL,
+				   SYSTEM_ERROR_INTR_ON_MESG_MASK);
 
 	aer_pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ERR);
 	/* Clear error status */
@@ -396,9 +394,8 @@ static void aer_error_resume(struct pci_dev *dev)
 	u16 reg16;
 
 	/* Clean up Root device status */
-	pos = pci_pcie_cap(dev);
-	pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, &reg16);
-	pci_write_config_word(dev, pos + PCI_EXP_DEVSTA, reg16);
+	pcie_capability_read_word(dev, PCI_EXP_DEVSTA, &reg16);
+	pcie_capability_write_word(dev, PCI_EXP_DEVSTA, reg16);
 
 	/* Clean AER Root Error Status */
 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);

drivers/pci/pcie/aer/aerdrv_core.c

@@ -32,53 +32,28 @@ static bool nosourceid;
 module_param(forceload, bool, 0);
 module_param(nosourceid, bool, 0);
 
+#define	PCI_EXP_AER_FLAGS	(PCI_EXP_DEVCTL_CERE | PCI_EXP_DEVCTL_NFERE | \
+				 PCI_EXP_DEVCTL_FERE | PCI_EXP_DEVCTL_URRE)
+
 int pci_enable_pcie_error_reporting(struct pci_dev *dev)
 {
-	u16 reg16 = 0;
-	int pos;
-
 	if (pcie_aer_get_firmware_first(dev))
 		return -EIO;
 
-	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
-	if (!pos)
-		return -EIO;
-
-	pos = pci_pcie_cap(dev);
-	if (!pos)
+	if (!pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR))
 		return -EIO;
 
-	pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &reg16);
-	reg16 |= (PCI_EXP_DEVCTL_CERE |
-		PCI_EXP_DEVCTL_NFERE |
-		PCI_EXP_DEVCTL_FERE |
-		PCI_EXP_DEVCTL_URRE);
-	pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, reg16);
-
-	return 0;
+	return pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_AER_FLAGS);
 }
 EXPORT_SYMBOL_GPL(pci_enable_pcie_error_reporting);
 
 int pci_disable_pcie_error_reporting(struct pci_dev *dev)
 {
-	u16 reg16 = 0;
-	int pos;
-
 	if (pcie_aer_get_firmware_first(dev))
 		return -EIO;
 
-	pos = pci_pcie_cap(dev);
-	if (!pos)
-		return -EIO;
-
-	pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &reg16);
-	reg16 &= ~(PCI_EXP_DEVCTL_CERE |
-		PCI_EXP_DEVCTL_NFERE |
-		PCI_EXP_DEVCTL_FERE |
-		PCI_EXP_DEVCTL_URRE);
-	pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, reg16);
-
-	return 0;
+	return pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
+					  PCI_EXP_AER_FLAGS);
 }
 EXPORT_SYMBOL_GPL(pci_disable_pcie_error_reporting);
 
@@ -151,18 +126,12 @@ static bool is_error_source(struct pci_dev *dev, struct aer_err_info *e_info)
 	 */
 	if (atomic_read(&dev->enable_cnt) == 0)
 		return false;
-	pos = pci_pcie_cap(dev);
-	if (!pos)
-		return false;
 
 	/* Check if AER is enabled */
-	pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &reg16);
-	if (!(reg16 & (
-		PCI_EXP_DEVCTL_CERE |
-		PCI_EXP_DEVCTL_NFERE |
-		PCI_EXP_DEVCTL_FERE |
-		PCI_EXP_DEVCTL_URRE)))
+	pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &reg16);
+	if (!(reg16 & PCI_EXP_AER_FLAGS))
 		return false;
+
 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
 	if (!pos)
 		return false;