powerpc/pci: Trace more information from pci_dn

Originally, EEH probes on device_node or pci_dev and populates the
corresponding eeh_dev. In the subsequent patches, EEH will probes
on pci_dn and populates the corresponding eeh_dev. So we have to
cache some information in pci_dn, either from device_node or SRIOV
PF's enablement platform hook, to populate the eeh_dev properly.

The motivation to probe pci_dn, instead of device node or pci_dev,
to populate eeh_dev is SRIOV VFs are dynamically created and we
don't have the corresponding device nodes for them.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/include/asm/pci-bridge.h

@@ -159,6 +159,9 @@ struct pci_dn {
 
 	int	busno;			/* pci bus number */
 	int	devfn;			/* pci device and function number */
+	int	vendor_id;		/* Vendor ID */
+	int	device_id;		/* Device ID */
+	int	class_code;		/* Device class code */
 
 	struct  pci_dn *parent;
 	struct  pci_controller *phb;	/* for pci devices */

arch/powerpc/kernel/pci_dn.c

@@ -166,6 +166,15 @@ void *update_dn_pci_info(struct device_node *dn, void *data)
 		pdn->devfn = (addr >> 8) & 0xff;
 	}
 
+	/* vendor/device IDs and class code */
+	regs = of_get_property(dn, "vendor-id", NULL);
+	pdn->vendor_id = regs ? of_read_number(regs, 1) : 0;
+	regs = of_get_property(dn, "device-id", NULL);
+	pdn->device_id = regs ? of_read_number(regs, 1) : 0;
+	regs = of_get_property(dn, "class-code", NULL);
+	pdn->class_code = regs ? of_read_number(regs, 1) : 0;
+
+	/* Extended config space */
 	pdn->pci_ext_config_space = (type && of_read_number(type, 1) == 1);
 
 	/* Attach to parent node */
@@ -255,6 +264,7 @@ void pci_devs_phb_init_dynamic(struct pci_controller *phb)
 	pdn = dn->data;
 	if (pdn) {
 		pdn->devfn = pdn->busno = -1;
+		pdn->vendor_id = pdn->device_id = pdn->class_code = 0;
 		pdn->phb = phb;
 		phb->pci_data = pdn;
 	}