From 4ce6d5fee4891af13ab3e1292494e24efc7f45d9 Mon Sep 17 00:00:00 2001 From: Karsten Wiese Date: Sat, 3 Sep 2005 15:56:33 -0700 Subject: [PATCH] --- yaml --- r: 6973 b: refs/heads/master c: a1740913cae231fb8e485306fb09671ed9a6e550 h: refs/heads/master i: 6971: 95da6a9b993a509ead7b91650511e00b5b624b60 v: v3 --- [refs] | 2 +- trunk/drivers/pci/quirks.c | 19 +++++++++++++++++++ 2 files changed, 20 insertions(+), 1 deletion(-) diff --git a/[refs] b/[refs] index 31f8460c296a..c19668b89bb3 100644 --- a/[refs] +++ b/[refs] @@ -1,2 +1,2 @@ --- -refs/heads/master: 252943efcfce945d8dd3738ca4c4b9cbeb4f3fa9 +refs/heads/master: a1740913cae231fb8e485306fb09671ed9a6e550 diff --git a/trunk/drivers/pci/quirks.c b/trunk/drivers/pci/quirks.c index bb36bb69803f..140354a2aa72 100644 --- a/trunk/drivers/pci/quirks.c +++ b/trunk/drivers/pci/quirks.c @@ -421,6 +421,25 @@ static void __devinit quirk_via_ioapic(struct pci_dev *dev) } DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C686, quirk_via_ioapic ); +/* + * VIA 8237: Some BIOSs don't set the 'Bypass APIC De-Assert Message' Bit. + * This leads to doubled level interrupt rates. + * Set this bit to get rid of cycle wastage. + * Otherwise uncritical. + */ +static void __devinit quirk_via_vt8237_bypass_apic_deassert(struct pci_dev *dev) +{ + u8 misc_control2; +#define BYPASS_APIC_DEASSERT 8 + + pci_read_config_byte(dev, 0x5B, &misc_control2); + if (!(misc_control2 & BYPASS_APIC_DEASSERT)) { + printk(KERN_INFO "PCI: Bypassing VIA 8237 APIC De-Assert Message\n"); + pci_write_config_byte(dev, 0x5B, misc_control2|BYPASS_APIC_DEASSERT); + } +} +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237, quirk_via_vt8237_bypass_apic_deassert); + /* * The AMD io apic can hang the box when an apic irq is masked. * We check all revs >= B0 (yet not in the pre production!) as the bug