drm/amdgpu: make sure vertical front porch is at least 1

hw doesn't like a 0 value. Signed-off-by: Alex Deucher <[email protected]> Cc: [email protected]
lucamilanesio · May 3, 2016 · 0126d4b · 0126d4b
1 parent 3104b81
commit 0126d4b
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c b/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c
@@ -298,6 +298,10 @@ bool amdgpu_atombios_encoder_mode_fixup(struct drm_encoder *encoder,
 	    && (mode->crtc_vsync_start < (mode->crtc_vdisplay + 2)))
 		adjusted_mode->crtc_vsync_start = adjusted_mode->crtc_vdisplay + 2;
 
+	/* vertical FP must be at least 1 */
+	if (mode->crtc_vsync_start == mode->crtc_vdisplay)
+		adjusted_mode->crtc_vsync_start++;
+
 	/* get the native mode for scaling */
 	if (amdgpu_encoder->active_device & (ATOM_DEVICE_LCD_SUPPORT))
 		amdgpu_panel_mode_fixup(encoder, adjusted_mode);