[PATCH] AGP support for powermac G5

This patch adds AGP support for the U3 northbridge used in Apple G5
machines to drivers/char/agp/uninorth-agp.c.  This patch is based on
earlier work by Jerome Glisse.  With this patch, the driver works in
both ppc32 and ppc64 kernels.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/char/agp/Kconfig

 config AGP
 	tristate "/dev/agpgart (AGP Support)" if !GART_IOMMU
-	depends on ALPHA || IA64 || PPC32 || X86
+	depends on ALPHA || IA64 || PPC || X86
 	default y if GART_IOMMU
 	---help---
 	  AGP (Accelerated Graphics Port) is a bus system mainly used to
@@ -146,11 +146,11 @@ config AGP_ALPHA_CORE
 	default AGP
 
 config AGP_UNINORTH
-	tristate "Apple UniNorth AGP support"
+	tristate "Apple UniNorth & U3 AGP support"
 	depends on AGP && PPC_PMAC
 	help
 	  This option gives you AGP support for Apple machines with a
-	  UniNorth bridge.
+	  UniNorth or U3 (Apple G5) bridge.
 
 config AGP_EFFICEON
 	tristate "Transmeta Efficeon support"

include/asm-ppc/uninorth.h

@@ -27,13 +27,18 @@
 #define UNI_N_CFG_AGP_BASE		0x90
 #define UNI_N_CFG_GART_CTRL		0x94
 #define UNI_N_CFG_INTERNAL_STATUS	0x98
+#define UNI_N_CFG_GART_DUMMY_PAGE	0xa4
 
 /* UNI_N_CFG_GART_CTRL bits definitions */
-/* Not U3 */
 #define UNI_N_CFG_GART_INVAL		0x00000001
 #define UNI_N_CFG_GART_ENABLE		0x00000100
 #define UNI_N_CFG_GART_2xRESET		0x00010000
 #define UNI_N_CFG_GART_DISSBADET	0x00020000
+/* The following seems to only be used only on U3 <j.glisse@gmail.com> */
+#define U3_N_CFG_GART_SYNCMODE		0x00040000
+#define U3_N_CFG_GART_PERFRD		0x00080000
+#define U3_N_CFG_GART_B2BGNT		0x00200000
+#define U3_N_CFG_GART_FASTDDR		0x00400000
 
 /* My understanding of UniNorth AGP as of UniNorth rev 1.0x,
  * revision 1.5 (x4 AGP) may need further changes.

include/asm-ppc64/agp.h

+#ifndef AGP_H
+#define AGP_H 1
+
+#include <asm/io.h>
+
+/* nothing much needed here */
+
+#define map_page_into_agp(page)
+#define unmap_page_from_agp(page)
+#define flush_agp_mappings()
+#define flush_agp_cache() mb()
+
+#endif

include/linux/pci_ids.h

@@ -876,10 +876,13 @@
 #define PCI_DEVICE_ID_APPLE_IPID_ATA100	0x003b
 #define PCI_DEVICE_ID_APPLE_KEYLARGO_I	0x003e
 #define PCI_DEVICE_ID_APPLE_K2_ATA100	0x0043
+#define PCI_DEVICE_ID_APPLE_U3_AGP	0x004b
 #define PCI_DEVICE_ID_APPLE_K2_GMAC	0x004c
 #define PCI_DEVICE_ID_APPLE_SH_ATA      0x0050
 #define PCI_DEVICE_ID_APPLE_SH_SUNGEM   0x0051
 #define PCI_DEVICE_ID_APPLE_SH_FW       0x0052
+#define PCI_DEVICE_ID_APPLE_U3L_AGP	0x0058
+#define PCI_DEVICE_ID_APPLE_U3H_AGP	0x0059
 #define PCI_DEVICE_ID_APPLE_TIGON3	0x1645
 
 #define PCI_VENDOR_ID_YAMAHA		0x1073