x86: move pci fixup to pci-dma.c

via_no_dac provides a fixup that is the same for both
architectures. Move it to pci-dma.c.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 9144336..48cccbe 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -1,12 +1,16 @@
 #include <linux/dma-mapping.h>
 #include <linux/dmar.h>
 #include <linux/bootmem.h>
+#include <linux/pci.h>
 
 #include <asm/proto.h>
 #include <asm/dma.h>
 #include <asm/gart.h>
 #include <asm/calgary.h>
 
+int forbid_dac __read_mostly;
+EXPORT_SYMBOL(forbid_dac);
+
 const struct dma_mapping_ops *dma_ops;
 EXPORT_SYMBOL(dma_ops);
 
@@ -121,3 +125,17 @@
 }
 /* Must execute after PCI subsystem */
 fs_initcall(pci_iommu_init);
+
+#ifdef CONFIG_PCI
+/* Many VIA bridges seem to corrupt data for DAC. Disable it here */
+
+static __devinit void via_no_dac(struct pci_dev *dev)
+{
+	if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI && forbid_dac == 0) {
+		printk(KERN_INFO "PCI: VIA PCI bridge detected."
+				 "Disabling DAC.\n");
+		forbid_dac = 1;
+	}
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_VIA, PCI_ANY_ID, via_no_dac);
+#endif