From 6f8a1b335fde143b7407036e2368d3cd6eb55674 Mon Sep 17 00:00:00 2001 From: Neil Horman Date: Wed, 12 Mar 2014 14:44:33 -0400 Subject: [PATCH] x86: Adjust irq remapping quirk for older revisions of 5500/5520 chipsets Commit 03bbcb2e7e2 (iommu/vt-d: add quirk for broken interrupt remapping on 55XX chipsets) properly disables irq remapping on the 5500/5520 chipsets that don't correctly perform that feature. However, when I wrote it, I followed the errata sheet linked in that commit too closely, and explicitly tied the activation of the quirk to revision 0x13 of the chip, under the assumption that earlier revisions were not in the field. Recently a system was reported to be suffering from this remap bug and the quirk hadn't triggered, because the revision id register read at a lower value that 0x13, so the quirk test failed improperly. Given this, it seems only prudent to adjust this quirk so that any revision less than 0x13 has the quirk asserted. [ tglx: Removed the 0x12 comparison of pci id 3405 as this is covered by the <= 0x13 check already ] Signed-off-by: Neil Horman Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: x86@kernel.org Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1394649873-14913-1-git-send-email-nhorman@tuxdriver.com Signed-off-by: Thomas Gleixner --- arch/x86/kernel/early-quirks.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/early-quirks.c b/arch/x86/kernel/early-quirks.c index bc4a088f9023..6d7d5a1260a6 100644 --- a/arch/x86/kernel/early-quirks.c +++ b/arch/x86/kernel/early-quirks.c @@ -203,18 +203,15 @@ static void __init intel_remapping_check(int num, int slot, int func) revision = read_pci_config_byte(num, slot, func, PCI_REVISION_ID); /* - * Revision 13 of all triggering devices id in this quirk have - * a problem draining interrupts when irq remapping is enabled, - * and should be flagged as broken. Additionally revisions 0x12 - * and 0x22 of device id 0x3405 has this problem. + * Revision <= 13 of all triggering devices id in this quirk + * have a problem draining interrupts when irq remapping is + * enabled, and should be flagged as broken. Additionally + * revision 0x22 of device id 0x3405 has this problem. */ - if (revision == 0x13) + if (revision <= 0x13) set_irq_remapping_broken(); - else if ((device == 0x3405) && - ((revision == 0x12) || - (revision == 0x22))) + else if (device == 0x3405 && revision == 0x22) set_irq_remapping_broken(); - } /* -- 2.20.1