x86 gart: factor out common code

Cleanup gart handling on amd64 a bit: move common code into
enable_gart_translation , and use symbolic register names where
appropriate.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/include/asm-x86/gart.h b/include/asm-x86/gart.h
index 248e577..6f22786 100644
--- a/include/asm-x86/gart.h
+++ b/include/asm-x86/gart.h
@@ -52,4 +52,21 @@
 #define AMD64_GARTCACHECTL	0x9c
 #define AMD64_GARTEN		(1<<0)
 
+static inline void enable_gart_translation(struct pci_dev *dev, u64 addr)
+{
+	u32 tmp, ctl;
+
+        /* address of the mappings table */
+        addr >>= 12;
+        tmp = (u32) addr<<4;
+        tmp &= ~0xf;
+        pci_write_config_dword(dev, AMD64_GARTTABLEBASE, tmp);
+
+        /* Enable GART translation for this hammer. */
+        pci_read_config_dword(dev, AMD64_GARTAPERTURECTL, &ctl);
+        ctl |= GARTEN;
+        ctl &= ~(DISGARTCPU | DISGARTIO);
+        pci_write_config_dword(dev, AMD64_GARTAPERTURECTL, ctl);
+}
+
 #endif