PCI: Call pci_read_bridge_bases() from core instead of arch code

When we scan a PCI bus, we read PCI-PCI bridge window registers with
pci_read_bridge_bases() so we can validate the resource hierarchy.  Most
architectures call pci_read_bridge_bases() from pcibios_fixup_bus(), but
PCI-PCI bridges are not arch-specific, so this doesn't need to be in
arch-specific code.

Call pci_read_bridge_bases() directly from the PCI core instead of from
arch code.

For alpha and mips, we now call pci_read_bridge_bases() always; previously
we only called it if PCI_PROBE_ONLY was set.

[bhelgaas: changelog]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Ralf Baechle <ralf@linux-mips.org>
CC: James E.J. Bottomley <jejb@parisc-linux.org>
CC: Michael Ellerman <mpe@ellerman.id.au>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: David Howells <dhowells@redhat.com>
CC: Russell King <linux@arm.linux.org.uk>
CC: Tony Luck <tony.luck@intel.com>
CC: David S. Miller <davem@davemloft.net>
CC: Ingo Molnar <mingo@redhat.com>
CC: Guenter Roeck <linux@roeck-us.net>
CC: Michal Simek <monstr@monstr.eu>
CC: Chris Zankel <chris@zankel.net>

arch/alpha/kernel/pci.c

@@ -242,12 +242,7 @@ pci_restore_srm_config(void)
 
 void pcibios_fixup_bus(struct pci_bus *bus)
 {
-	struct pci_dev *dev = bus->self;
+	struct pci_dev *dev;
-
-	if (pci_has_flag(PCI_PROBE_ONLY) && dev &&
- 		   (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
- 		pci_read_bridge_bases(bus);
-	} 
 
 	list_for_each_entry(dev, &bus->devices, bus_list) {
 		pdev_save_srm_config(dev);

arch/frv/mb93090-mb00/pci-vdk.c

@@ -294,8 +294,6 @@ void pcibios_fixup_bus(struct pci_bus *bus)
 	printk("### PCIBIOS_FIXUP_BUS(%d)\n",bus->number);
 #endif
 
-	pci_read_bridge_bases(bus);
-
 	if (bus->number == 0) {
 		struct pci_dev *dev;
 		list_for_each_entry(dev, &bus->devices, bus_list) {

arch/ia64/pci/pci.c

@@ -533,10 +533,9 @@ void pcibios_fixup_bus(struct pci_bus *b)
 {
 	struct pci_dev *dev;
 
-	if (b->self) {
+	if (b->self)
-		pci_read_bridge_bases(b);
 		pcibios_fixup_bridge_resources(b->self);
-	}
+
 	list_for_each_entry(dev, &b->devices, bus_list)
 		pcibios_fixup_device_resources(dev);
 	platform_pci_fixup_bus(b);

arch/microblaze/pci/pci-common.c

@@ -863,14 +863,7 @@ void pcibios_setup_bus_devices(struct pci_bus *bus)
 
 void pcibios_fixup_bus(struct pci_bus *bus)
 {
-	/* When called from the generic PCI probe, read PCI<->PCI bridge
+	/* Fixup the bus */
-	 * bases. This is -not- called when generating the PCI tree from
-	 * the OF device-tree.
-	 */
-	if (bus->self != NULL)
-		pci_read_bridge_bases(bus);
-
-	/* Now fixup the bus bus */
 	pcibios_setup_bus_self(bus);
 
 	/* Now fixup devices on that bus */

arch/mips/pci/pci.c

@@ -311,12 +311,6 @@ int pcibios_enable_device(struct pci_dev *dev, int mask)
 
 void pcibios_fixup_bus(struct pci_bus *bus)
 {
-	struct pci_dev *dev = bus->self;
-
-	if (pci_has_flag(PCI_PROBE_ONLY) && dev &&
-	    (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
-		pci_read_bridge_bases(bus);
-	}
 }
 
 EXPORT_SYMBOL(PCIBIOS_MIN_IO);

arch/mn10300/unit-asb2305/pci.c

@@ -324,7 +324,6 @@ void pcibios_fixup_bus(struct pci_bus *bus)
 	struct pci_dev *dev;
 
 	if (bus->self) {
-		pci_read_bridge_bases(bus);
 		pcibios_fixup_bridge_resources(bus->self);
 	}
 

arch/powerpc/kernel/pci-common.c

@@ -1044,13 +1044,7 @@ void pcibios_set_master(struct pci_dev *dev)
 
 void pcibios_fixup_bus(struct pci_bus *bus)
 {
-	/* When called from the generic PCI probe, read PCI<->PCI bridge
+	/* Fixup the bus */
-	 * bases. This is -not- called when generating the PCI tree from
-	 * the OF device-tree.
-	 */
-	pci_read_bridge_bases(bus);
-
-	/* Now fixup the bus bus */
 	pcibios_setup_bus_self(bus);
 
 	/* Now fixup devices on that bus */

arch/x86/pci/common.c

@@ -166,7 +166,6 @@ void pcibios_fixup_bus(struct pci_bus *b)
 {
 	struct pci_dev *dev;
 
-	pci_read_bridge_bases(b);
 	list_for_each_entry(dev, &b->devices, bus_list)
 		pcibios_fixup_device_resources(dev);
 }

arch/xtensa/kernel/pci.c

@@ -210,10 +210,6 @@ subsys_initcall(pcibios_init);
 
 void pcibios_fixup_bus(struct pci_bus *bus)
 {
-	if (bus->parent) {
-		/* This is a subordinate bridge */
-		pci_read_bridge_bases(bus);
-	}
 }
 
 void pcibios_set_master(struct pci_dev *dev)

drivers/parisc/dino.c

@@ -560,9 +560,6 @@ dino_fixup_bus(struct pci_bus *bus)
 	} else if (bus->parent) {
 		int i;
 
-		pci_read_bridge_bases(bus);
-
-
 		for(i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) {
 			if((bus->self->resource[i].flags & 
 			    (IORESOURCE_IO | IORESOURCE_MEM)) == 0)

drivers/parisc/lba_pci.c

@@ -693,7 +693,6 @@ lba_fixup_bus(struct pci_bus *bus)
 	if (bus->parent) {
 		int i;
 		/* PCI-PCI Bridge */
-		pci_read_bridge_bases(bus);
 		for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++)
 			pci_claim_bridge_resource(bus->self, i);
 	} else {

drivers/pci/probe.c

@@ -826,6 +826,9 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
 			child->bridge_ctl = bctl;
 		}
 
+		/* Read and initialize bridge resources */
+		pci_read_bridge_bases(child);
+
 		cmax = pci_scan_child_bus(child);
 		if (cmax > subordinate)
 			dev_warn(&dev->dev, "bridge has subordinate %02x but max busn %02x\n",
@@ -886,6 +889,9 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
 
 		if (!is_cardbus) {
 			child->bridge_ctl = bctl;
+
+			/* Read and initialize bridge resources */
+			pci_read_bridge_bases(child);
 			max = pci_scan_child_bus(child);
 		} else {
 			/*