[PATCH] drm/amdgpu: fix that issue that the number of the crtc of the 3250c is not correct

[RyanLin <Tsung-Hua.Lin@amd.com>]

[Why]
External displays take priority over internal display when there are fewer 
display controllers than displays.

[How]
The root cause is because of that number of the crtc is not correct.
The number of the crtc on the 3250c is 3, but on the 3500c is 4.
On the source code, we can see that number of the crtc has been fixed at 4.
Needs to set the num_crtc to 3 for 3250c platform.

Signed-off-by: RyanLin <Tsung-Hua.Lin@amd.com>
Change-Id: I837df7101cc4849d2c3021fd529b4061edab4bb1
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 40c91b448f7d..dbeef7b57a9b 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2738,9 +2738,15 @@ static int dm_early_init(void *handle)
 		break;
 #if defined(CONFIG_DRM_AMD_DC_DCN1_0)
 	case CHIP_RAVEN:
-		adev->mode_info.num_crtc = 4;
-		adev->mode_info.num_hpd = 4;
-		adev->mode_info.num_dig = 4;
+		if (adev->rev_id >= 8) { //chip_name = "raven2";
+			adev->mode_info.num_crtc = 3;
+			adev->mode_info.num_hpd = 3;
+			adev->mode_info.num_dig = 3;
+		} else {
+			adev->mode_info.num_crtc = 4;
+			adev->mode_info.num_hpd = 4;
+			adev->mode_info.num_dig = 4;
+		}
 		break;
 #endif
 #if defined(CONFIG_DRM_AMD_DC_DCN2_0)
-- 
2.25.1