From 274e1bbdeeaf16e71418f11f5f305ab26061f2c2 Mon Sep 17 00:00:00 2001 From: "Siddha, Suresh B" Date: Thu, 7 Dec 2006 02:14:10 +0100 Subject: [PATCH] x86: add write_pci_config_byte() to direct PCI access routines Mechanism of selecting physical mode in genapic when cpu hotplug is enabled on x86_64, broke the quirk(quirk_intel_irqbalance()) introduced for working around the transposing interrupt message errata in E7520/E7320/E7525 (revision ID 0x9 and below. errata #23 in http://download.intel.com/design/chipsets/specupdt/30304203.pdf). This errata requires the mode to be in logical flat, so that interrupts can be directed to more than one cpu(and thus use hardware IRQ balancing enabled by BIOS on these platforms). Following four patches fixes this by moving the quirk to early quirk and forcing the x86_64 genapic selection to logical flat on these platforms. Thanks to Shaohua for pointing out the breakage. This patch: Add write_pci_config_byte() to direct PCI access routines Signed-off-by: Suresh Siddha Signed-off-by: Andi Kleen Cc: Andi Kleen Cc: "Li, Shaohua" Signed-off-by: Andrew Morton --- arch/i386/pci/early.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'arch/i386/pci') diff --git a/arch/i386/pci/early.c b/arch/i386/pci/early.c index 713d6c866cae..42df4b6606df 100644 --- a/arch/i386/pci/early.c +++ b/arch/i386/pci/early.c @@ -45,6 +45,13 @@ void write_pci_config(u8 bus, u8 slot, u8 func, u8 offset, outl(val, 0xcfc); } +void write_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset, u8 val) +{ + PDprintk("%x writing to %x: %x\n", slot, offset, val); + outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8); + outb(val, 0xcfc); +} + int early_pci_allowed(void) { return (pci_probe & (PCI_PROBE_CONF1|PCI_PROBE_NOEARLY)) == -- cgit v1.2.1