On Mon, Apr 30, 2001 at 05:58:40PM +0100, Alan Cox wrote:
> > Attached is a patch to the quirks.c in linux kernel 2.4.4 that fixes the
> > sound corruption problem (thanks to Dan Hollis for the info). Do I have to
> > send this anywhere else as well?
>
> It seems very broken
>
> > - { PCI_FIXUP_FINAL, PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8363_0,
> quirk_vialatency },
> > + { PCI_FIXUP_FINAL, PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C686,
> quirk_vialatency },
>
> You are hacking the wrong chip..
That's the first version I sent which was admittedly broken. About 20
minutes later I sent the fixed version (mail with subject: "Re: 2.4.4 Sound
corruption [PATCH] NEW, ignore previous patch"). In case you can't find
this, I've re-attached the patch.
Regards,
Charl
--
charl p. botha | computer graphics and cad/cam
http://cpbotha.net/ | http://www.cg.its.tudelft.nl/
--- quirks.c-2.4.4 Mon Apr 30 01:50:36 2001
+++ quirks.c Mon Apr 30 03:54:08 2001
@@ -88,23 +88,44 @@
* VIA Apollo KT133 needs PCI latency patch
* Made according to a windows driver based patch by George E. Breese
* see PCI Latency Adjust on http://www.viahardware.com/download/viatweak.shtm
+ * Also see http://home.tiscalinet.de/au-ja/review-kt133a-1-en.html for
+ * the info on which Mr Breese based his work.
*/
static void __init quirk_vialatency(struct pci_dev *dev)
{
u8 r70;
-
- printk(KERN_INFO "Applying VIA PCI latency patch.\n");
- /*
- * In register 0x70, mask off bit 2 (PCI Master read caching)
- * and 1 (Delay Transaction)
+ u8 rev;
+ struct pci_dev *vt82c686;
+
+
+ /* we want to look for a VT82C686 south bridge, and then apply the via latency
+ * patch if we find that it's a 686B (by revision) <[EMAIL PROTECTED]>
*/
- pci_read_config_byte(dev, 0x70, &r70);
- r70 &= 0xf9;
- pci_write_config_byte(dev, 0x70, r70);
- /*
- * Turn off PCI Latency timeout (set to 0 clocks)
- */
- pci_write_config_byte(dev, 0x75, 0x80);
+ vt82c686 = pci_find_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C686, NULL);
+ if (vt82c686)
+ {
+ pci_read_config_byte(vt82c686, PCI_CLASS_REVISION, &rev);
+ /* 0x40 - 0x4f == 686B, 0x10 - 0x2f == 686A; thanks Dan Hollis */
+ if (rev >= 0x40 && rev <= 0x4f)
+ {
+ printk(KERN_INFO "Applying VIA PCI latency patch (found
+VT82C686B).\n");
+ /*
+ * In register 0x70, mask off bit 2 (PCI Master read
+caching)
+ * and 1 (Delay Transaction)
+ */
+ pci_read_config_byte(dev, 0x70, &r70);
+ r70 &= 0xf9;
+ pci_write_config_byte(dev, 0x70, r70);
+ /*
+ * Turn off PCI Latency timeout (set to 0 clocks)
+ */
+ pci_write_config_byte(dev, 0x75, 0x80);
+ }
+ else
+ {
+ printk(KERN_INFO "Found VT82C686A, not applying VIA latency
+patch.\n");
+ }
+ } /* if (vt82c686) ... */
}
/*
