From: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
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@jurassic.park.msu.ru>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
drivers/pci/probe.c | 2 +-
drivers/pci/setup-bus.c | 12 ------------
2 files changed, 1 insertion(+), 13 deletions(-)
diff -puN drivers/pci/probe.c~remove-pci_bridge_ctl_vga-handling-from-setup-busc drivers/pci/probe.c
--- devel/drivers/pci/probe.c~remove-pci_bridge_ctl_vga-handling-from-setup-busc 2005-07-14 15:36:37.000000000 -0700
+++ devel-akpm/drivers/pci/probe.c 2005-07-14 15:36:37.000000000 -0700
@@ -507,7 +507,7 @@ int __devinit pci_scan_bridge(struct pci
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
diff -puN drivers/pci/setup-bus.c~remove-pci_bridge_ctl_vga-handling-from-setup-busc drivers/pci/setup-bus.c
--- devel/drivers/pci/setup-bus.c~remove-pci_bridge_ctl_vga-handling-from-setup-busc 2005-07-14 15:36:37.000000000 -0700
+++ devel-akpm/drivers/pci/setup-bus.c 2005-07-14 15:36:37.000000000 -0700
@@ -51,8 +51,6 @@ pbus_assign_resources_sorted(struct pci_
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 @@ pbus_assign_resources_sorted(struct pci_
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);
}
@@ -507,12 +501,6 @@ pci_bus_assign_resources(struct pci_bus
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)
_