[PATCH] x86: pci_assign_unassigned_resources() update

I had some time to think about PCI assign issues in 2.6.13-rc series.

The major problem here is that we call pci_assign_unassigned_resources()
way too early - at subsys_initcall level. Therefore we give no chances
to ACPI and PnP routines (called at fs_initcall level) to reserve their
respective resources properly, as the comments in drivers/pnp/system.c
and drivers/acpi/motherboard.c suggest:

 /**
  * Reserve motherboard resources after PCI claim BARs,
  * but before PCI assign resources for uninitialized PCI devices
  */

So I moved the pci_assign_unassigned_resources() call to
pcibios_assign_resources() (fs_initcall), which should hopefully fix a
lot of problems and make PCIBIOS_MIN_IO tweaks unnecessary.

Other changes:
- remove resource assignment code from pcibios_assign_resources(), since
  it duplicates pci_assign_unassigned_resources() functionality and
  actually does nothing in 2.6.13;
- modify ROM assignment code as per Ben's suggestion: try to use firmware
  settings by default (if PCI_ASSIGN_ROMS is not set);
- set CARDBUS_IO_SIZE back to 4K as it's a wonderful stress test for
  various setups.

Confirmed by Tero Roponen <teanropo@cc.jyu.fi> (who had problems with
the 4kB CardBus IO size previously).

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 6d864c5..6b0e646 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -40,7 +40,7 @@
  * FIXME: IO should be max 256 bytes.  However, since we may
  * have a P2P bridge below a cardbus bridge, we need 4K.
  */
-#define CARDBUS_IO_SIZE		(256)
+#define CARDBUS_IO_SIZE		(4*1024)
 #define CARDBUS_MEM_SIZE	(32*1024*1024)
 
 static void __devinit