[patch 15/29] PCI: remove PCI_BRIDGE_CTL_VGA handling from setup-bus.c

[Greg KH]

From: Ivan Kokshaysky <ink@xxxxxxxxxxxxxxxxxxxx>

The setup-bus code doesn't work correctly for configurations
with more than one display adapter in the same PCI domain.
This stuff actually is a leftover of an early 2.4 PCI setup code
and apparently it stopped working after some "bridge_ctl" changes.
So the best thing we can do is just to remove it and rely on the fact
that any firmware *has* to configure VGA port forwarding for the boot
display device properly.

But then we need to ensure that the bus->bridge_ctl will always
contain valid information collected at the probe time, therefore
the following change in pci_scan_bridge() is needed.

Signed-off-by: Ivan Kokshaysky <ink@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 drivers/pci/probe.c     |    2 +-
 drivers/pci/setup-bus.c |   12 ------------
 2 files changed, 1 insertion(+), 13 deletions(-)

--- gregkh-2.6.orig/drivers/pci/probe.c	2005-07-29 11:29:50.000000000 -0700
+++ gregkh-2.6/drivers/pci/probe.c	2005-07-29 11:36:23.000000000 -0700
@@ -507,7 +507,7 @@
 		pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
 
 		if (!is_cardbus) {
-			child->bridge_ctl = PCI_BRIDGE_CTL_NO_ISA;
+			child->bridge_ctl = bctl | PCI_BRIDGE_CTL_NO_ISA;
 			/*
 			 * Adjust subordinate busnr in parent buses.
 			 * We do this before scanning for children because
--- gregkh-2.6.orig/drivers/pci/setup-bus.c	2005-07-29 11:29:50.000000000 -0700
+++ gregkh-2.6/drivers/pci/setup-bus.c	2005-07-29 11:36:23.000000000 -0700
@@ -51,8 +51,6 @@
 	struct resource_list head, *list, *tmp;
 	int idx;
 
-	bus->bridge_ctl &= ~PCI_BRIDGE_CTL_VGA;
-
 	head.next = NULL;
 	list_for_each_entry(dev, &bus->devices, bus_list) {
 		u16 class = dev->class >> 8;
@@ -62,10 +60,6 @@
 		    class == PCI_CLASS_BRIDGE_HOST)
 			continue;
 
-		if (class == PCI_CLASS_DISPLAY_VGA ||
-		    class == PCI_CLASS_NOT_DEFINED_VGA)
-			bus->bridge_ctl |= PCI_BRIDGE_CTL_VGA;
-
 		pdev_sort_resources(dev, &head);
 	}
 
@@ -509,12 +503,6 @@
 
 	pbus_assign_resources_sorted(bus);
 
-	if (bus->bridge_ctl & PCI_BRIDGE_CTL_VGA) {
-		/* Propagate presence of the VGA to upstream bridges */
-		for (b = bus; b->parent; b = b->parent) {
-			b->bridge_ctl |= PCI_BRIDGE_CTL_VGA;
-		}
-	}
 	list_for_each_entry(dev, &bus->devices, bus_list) {
 		b = dev->subordinate;
 		if (!b)

--
-
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