PCI: Disable cardbus bridge MEM1 prefetchable bit

Some BIOSes enable prefetch on both MEM0 and MEM1.  But the cardbus code
assumes MEM1 is non-pref...

Discussion could be found at:
	https://lkml.org/lkml/2012/1/12/1
	https://bugzilla.kernel.org/show_bug.cgi?id=41622#c23

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Tested-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Yinghai Lu 2012-02-10 15:33:46 -08:00 committed by Jesse Barnes
parent 5b415f1e79
commit dcef0d06b3
1 changed files with 8 additions and 0 deletions

View File

@ -914,6 +914,14 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
if (realloc_head)
add_to_list(realloc_head, bridge, b_res+1, pci_cardbus_io_size, 0 /* dont care */);
/* MEM1 must not be pref mmio */
pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM1) {
ctrl &= ~PCI_CB_BRIDGE_CTL_PREFETCH_MEM1;
pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
}
/*
* Check whether prefetchable memory is supported
* by this bridge.