lkml.org 
[lkml]   [2000]   [Sep]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
In article <39C70CB0.AEB0DF8E@sgi.com>, Dag Bakke  <dagb@sgi.com> wrote:
>Tigran Aivazian wrote:
>>
>> On Mon, 18 Sep 2000, Derek Wildstar wrote:
>>
>> > On 18 Sep 2000, Alex Romosan wrote:
>> >
>> > I get the same thing with a Xircon realport 10/100/modem card. Works
>> > great in test9-pre1 and test8.
>> >
>> > -dwild
>> >
>>
>> did you try this patch?
>>
>> --- linux/drivers/pci/pci.c Mon Sep 18 12:35:11 2000
>> +++ work/drivers/pci/pci.c Mon Sep 18 13:12:20 2000
>> @@ -714,7 +714,7 @@
>> * We need to blast all three values with a single write.
>> */
>> pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
>> - if (!is_cardbus) {
>> + if (is_cardbus) {
>> /* Now we can scan all subordinate buses... */
>> max = pci_do_scan_bus(child);
>> } else {
>>
>
>
>I did.
>Didn't work for me.
>My Xircom is still being detected. But PCI resource allocation still fails.
>I'll be happy to set up a remote debug session for anyone interested...

There seem to be two potential problems with the new code. How about
this instead:

First off, it's doing the subordinate bus write with a byte write, which
is, as far as I can tell, not legal. When you update the bus
information, you have to update it all at the same time.

Does it help if you change drivers/pci/pci.c pci_scan_bridge(), the line
that says

pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);

and you replace that with

buses = (buses & 0xff00ffff) | ((unsigned int)(child->subordinate) << 16);
pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
instead.

Second, if the cardbus bridge is already allocated by the BIOS, the "max
bus" logic looks bogus. It looks like

if (!is_cardbus) {
unsigned int cmax = pci_do_scan_bus(child);
if (cmax > max) max = cmax;
}
and it _should_ probably have something like

if (!is_cardbus) {
.. same logic ..
} else {
unsigned int cmax = child->subordinate + 3;
if (cmax > max) max = cmax;
}
because otherwise we'd completely ignore the cardbus "max" values as far
as I can tell, and if the machine has another bus it might be given the
same bus value as the already-configured cardbus bridge.

Do the above two fixes help? If not, I suspect that we're better off
just reverting the new PCI bus allocation until it's fixed.

Linus
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 12:38    [from the cache]
©2003-2011 Jasper Spaans