1 From: Tejun Heo <tj@kernel.org>
2 Subject: x86: disallow DAC for MCP51 PCI bridge
5 MCP51 corrupts DAC transfers. Disallow it. Reported by pgnet on
8 https://bugzilla.novell.com/show_bug.cgi?id=463829
10 Signed-off-by: Tejun Heo <tj@kernel.org>
11 Reported-by: pgnet <pgnet.trash@gmail.com>
12 Signed-off-by: Tejun Heo <teheo@suse.de>
14 arch/x86/kernel/pci-dma.c | 14 ++++++++++++++
15 1 file changed, 14 insertions(+)
17 Index: linux-2.6.27-SLE11_BRANCH/arch/x86/kernel/pci-dma.c
18 ===================================================================
19 --- linux-2.6.27-SLE11_BRANCH.orig/arch/x86/kernel/pci-dma.c
20 +++ linux-2.6.27-SLE11_BRANCH/arch/x86/kernel/pci-dma.c
21 @@ -415,4 +415,18 @@ static __devinit void via_no_dac(struct
24 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_VIA, PCI_ANY_ID, via_no_dac);
27 + * MCP51 PCI bridge corrupts data for DAC. Disable it. Reported in
30 +static __devinit void mcp51_no_dac(struct pci_dev *dev)
32 + if (forbid_dac == 0) {
34 + "PCI: MCP51 PCI bridge detected. Disabling DAC.\n");
38 +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, 0x026f, mcp51_no_dac);