[SPARC64]: Restrict PCI bus scanning on SUN4V.

On the PBM's first bus number, only allow device 0, function 0, to be
poked at with PCI config space accesses.

For some reason, this single device responds to all device numbers.

Also, reduce the verbiage of the debugging log printk's for PCI cfg
space accesses in the SUN4V PCI controller driver, so that it doesn't
overwhelm the slow SUN4V hypervisor console.

Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc64/kernel/pci_sun4v.c

@@ -517,8 +517,14 @@ struct pci_iommu_ops pci_sun4v_iommu_ops = {
 
 /* SUN4V PCI configuration space accessors. */
 
-static inline int pci_sun4v_out_of_range(struct pci_pbm_info *pbm, unsigned int bus)
+static inline int pci_sun4v_out_of_range(struct pci_pbm_info *pbm, unsigned int bus, unsigned int device, unsigned int func)
 {
+	if (bus == pbm->pci_first_busno) {
+		if (device == 0 && func == 0)
+			return 0;
+		return 1;
+	}
+
 	if (bus < pbm->pci_first_busno ||
 	    bus > pbm->pci_last_busno)
 		return 1;
@@ -535,15 +541,14 @@ static int pci_sun4v_read_pci_cfg(struct pci_bus *bus_dev, unsigned int devfn,
 	unsigned int func = PCI_FUNC(devfn);
 	unsigned long ret;
 
-	if (pci_sun4v_out_of_range(pbm, bus)) {
+	if (pci_sun4v_out_of_range(pbm, bus, device, func)) {
 		ret = ~0UL;
 	} else {
 		ret = pci_sun4v_config_get(devhandle,
 				HV_PCI_DEVICE_BUILD(bus, device, func),
 				where, size);
 #if 0
-		printk("read_pci_cfg: devh[%x] device[%08x] where[%x] sz[%d] "
-		       "== [%016lx]\n",
+		printk("rcfg: [%x:%x:%x:%d]=[%lx]\n",
 		       devhandle, HV_PCI_DEVICE_BUILD(bus, device, func),
 		       where, size, ret);
 #endif
@@ -574,15 +579,14 @@ static int pci_sun4v_write_pci_cfg(struct pci_bus *bus_dev, unsigned int devfn,
 	unsigned int func = PCI_FUNC(devfn);
 	unsigned long ret;
 
-	if (pci_sun4v_out_of_range(pbm, bus)) {
+	if (pci_sun4v_out_of_range(pbm, bus, device, func)) {
 		/* Do nothing. */
 	} else {
 		ret = pci_sun4v_config_put(devhandle,
 				HV_PCI_DEVICE_BUILD(bus, device, func),
 				where, size, value);
 #if 0
-		printk("write_pci_cfg: devh[%x] device[%08x] where[%x] sz[%d] "
-		       "val[%08x] == [%016lx]\n",
+		printk("wcfg: [%x:%x:%x:%d] v[%x] == [%lx]\n",
 		       devhandle, HV_PCI_DEVICE_BUILD(bus, device, func),
 		       where, size, value, ret);
 #endif
@@ -610,16 +614,13 @@ static void pbm_scan_bus(struct pci_controller_info *p,
 	memset(cookie, 0, sizeof(*cookie));
 	cookie->pbm = pbm;
 
-	pbm->pci_bus = pci_scan_bus(pbm->pci_first_busno,
-				    p->pci_ops,
-				    pbm);
+	pbm->pci_bus = pci_scan_bus(pbm->pci_first_busno, p->pci_ops, pbm);
 #if 0
 	pci_fixup_host_bridge_self(pbm->pci_bus);
 	pbm->pci_bus->self->sysdata = cookie;
 #endif
-
 	pci_fill_in_pbm_cookies(pbm->pci_bus, pbm,
-				prom_getchild(pbm->prom_node));
+				pbm->prom_node);
 	pci_record_assignments(pbm, pbm->pci_bus);
 	pci_assign_unassigned(pbm, pbm->pci_bus);
 	pci_fixup_irq(pbm, pbm->pci_bus);
@@ -884,19 +885,12 @@ static void pci_sun4v_iommu_init(struct pci_pbm_info *pbm)
 	probe_existing_entries(pbm, iommu);
 }
 
-/* Don't get this from the root nexus, get it from the "pci@0" node below.  */
 static void pci_sun4v_get_bus_range(struct pci_pbm_info *pbm)
 {
 	unsigned int busrange[2];
 	int prom_node = pbm->prom_node;
 	int err;
 
-	prom_node = prom_getchild(prom_node);
-	if (prom_node == 0) {
-		prom_printf("%s: Fatal error, no child OBP node.\n", pbm->name);
-		prom_halt();
-	}
-
 	err = prom_getproperty(prom_node, "bus-range",
 			       (char *)&busrange[0],
 			       sizeof(busrange));
@@ -929,7 +923,9 @@ static void pci_sun4v_pbm_init(struct pci_controller_info *p, int prom_node, u32
 	sprintf(pbm->name, "SUN4V-PCI%d PBM%c",
 		p->index, (pbm == &p->pbm_A ? 'A' : 'B'));
 
-	printk("%s: devhandle[%x]\n", pbm->name, pbm->devhandle);
+	printk("%s: devhandle[%x] prom_node[%x:%x]\n",
+	       pbm->name, pbm->devhandle,
+	       pbm->prom_node, prom_getchild(pbm->prom_node));
 
 	prom_getstring(prom_node, "name",
 		       pbm->prom_name, sizeof(pbm->prom_name));