drm/radeon/kms/legacy: set common regs to sane value

The DDX and radeonfb always set these regs to a sane value.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/r100.c

@@ -1675,6 +1675,17 @@ int r100_gpu_reset(struct radeon_device *rdev)
 	return 0;
 }
 
+void r100_set_common_regs(struct radeon_device *rdev)
+{
+	/* set these so they don't interfere with anything */
+	WREG32(RADEON_OV0_SCALE_CNTL, 0);
+	WREG32(RADEON_SUBPIC_CNTL, 0);
+	WREG32(RADEON_VIPH_CONTROL, 0);
+	WREG32(RADEON_I2C_CNTL_1, 0);
+	WREG32(RADEON_DVI_I2C_CNTL_1, 0);
+	WREG32(RADEON_CAP0_TRIG_CNTL, 0);
+	WREG32(RADEON_CAP1_TRIG_CNTL, 0);
+}
 
 /*
  * VRAM info
@@ -3129,6 +3140,9 @@ static int r100_startup(struct radeon_device *rdev)
 {
 	int r;
 
+	/* set common regs */
+	r100_set_common_regs(rdev);
+	/* program mc */
 	r100_mc_program(rdev);
 	/* Resume clock */
 	r100_clock_startup(rdev);

drivers/gpu/drm/radeon/r300.c

@@ -1186,6 +1186,9 @@ static int r300_startup(struct radeon_device *rdev)
 {
 	int r;
 
+	/* set common regs */
+	r100_set_common_regs(rdev);
+	/* program mc */
 	r300_mc_program(rdev);
 	/* Resume clock */
 	r300_clock_startup(rdev);

drivers/gpu/drm/radeon/r420.c

@@ -169,6 +169,9 @@ static int r420_startup(struct radeon_device *rdev)
 {
 	int r;
 
+	/* set common regs */
+	r100_set_common_regs(rdev);
+	/* program mc */
 	r300_mc_program(rdev);
 	/* Resume clock */
 	r420_clock_resume(rdev);

drivers/gpu/drm/radeon/radeon.h

@@ -1046,6 +1046,7 @@ extern int r100_cs_packet_parse(struct radeon_cs_parser *p,
 				struct radeon_cs_packet *pkt,
 				unsigned idx);
 extern void r100_enable_bm(struct radeon_device *rdev);
+extern void r100_set_common_regs(struct radeon_device *rdev);
 
 /* rv200,rv250,rv280 */
 extern void r200_set_safe_registers(struct radeon_device *rdev);