PCI/portdrv: Add #defines for AER and DPC Interrupt Message Number masks

In the AER case, the mask isn't strictly necessary because there are no
higher-order bits above the Interrupt Message Number, but using a #define
will make it possible to grep for it.
Suggested-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NDongdong Liu <liudongdong3@huawei.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>

drivers/pci/pcie/portdrv_core.c

@@ -114,7 +114,7 @@ static int pcie_port_enable_irq_vec(struct pci_dev *dev, int *irqs, int mask)
 		 */
 		pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
 		pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, &reg32);
-		entry = reg32 >> 27;
+		entry = (reg32 & PCI_ERR_ROOT_AER_IRQ) >> 27;
 		if (entry >= nr_entries)
 			goto out_free_irqs;
 
@@ -141,7 +141,7 @@ static int pcie_port_enable_irq_vec(struct pci_dev *dev, int *irqs, int mask)
 		 */
 		pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_DPC);
 		pci_read_config_word(dev, pos + PCI_EXP_DPC_CAP, &reg16);
-		entry = reg16 & 0x1f;
+		entry = reg16 & PCI_EXP_DPC_IRQ;
 		if (entry >= nr_entries)
 			goto out_free_irqs;
 

include/uapi/linux/pci_regs.h

@@ -746,6 +746,7 @@
 #define PCI_ERR_ROOT_FIRST_FATAL	0x00000010 /* First UNC is Fatal */
 #define PCI_ERR_ROOT_NONFATAL_RCV	0x00000020 /* Non-Fatal Received */
 #define PCI_ERR_ROOT_FATAL_RCV		0x00000040 /* Fatal Received */
+#define PCI_ERR_ROOT_AER_IRQ		0xf8000000 /* Advanced Error Interrupt Message Number */
 #define PCI_ERR_ROOT_ERR_SRC	52	/* Error Source Identification */
 
 /* Virtual Channel */
@@ -960,6 +961,7 @@
 
 /* Downstream Port Containment */
 #define PCI_EXP_DPC_CAP			4	/* DPC Capability */
+#define PCI_EXP_DPC_IRQ			0x1f	/* DPC Interrupt Message Number */
 #define  PCI_EXP_DPC_CAP_RP_EXT		0x20	/* Root Port Extensions for DPC */
 #define  PCI_EXP_DPC_CAP_POISONED_TLP	0x40	/* Poisoned TLP Egress Blocking Supported */
 #define  PCI_EXP_DPC_CAP_SW_TRIGGER	0x80	/* Software Triggering Supported */