drm/radeon: improve GPU lockup debugging info on r6xx/r7xx/r8xx/r9xx

Print various CP register that have valuable informations regarding
GPU lockup.

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/r600d.h b/drivers/gpu/drm/radeon/r600d.h
index 025fd5b..4b116ae 100644
--- a/drivers/gpu/drm/radeon/r600d.h
+++ b/drivers/gpu/drm/radeon/r600d.h
@@ -153,6 +153,9 @@
 
 #define	CONFIG_MEMSIZE					0x5428
 #define CONFIG_CNTL					0x5424
+#define	CP_STALLED_STAT1			0x8674
+#define	CP_STALLED_STAT2			0x8678
+#define	CP_BUSY_STAT				0x867C
 #define	CP_STAT						0x8680
 #define	CP_COHER_BASE					0x85F8
 #define	CP_DEBUG					0xC1FC