drm: change primary plane from 4K to 1080p

if connected to 4K screen change drm's primary plane
from 4K to 1080p and skip check function which check
if FB is bigger then CRTC.

Change-Id: I02c4b9c2b20fb3a5a0eecae5e7d9e69346c10033

Author: ck_zhang

drivers/gpu/drm/drm_atomic_helper.c

@@ -1754,6 +1754,13 @@ int drm_atomic_helper_set_config(struct drm_mode_set *set)
 }
 EXPORT_SYMBOL(drm_atomic_helper_set_config);
 
+
+
+#define WIDTH_4K		3840
+#define HEIGHT_4K		2160
+#define WIDTH_FAKE		1920
+#define HEIGHT_FAKE		1080
+
 /* just used from fb-helper and atomic-helper: */
 int __drm_atomic_helper_set_config(struct drm_mode_set *set,
 		struct drm_atomic_state *state)
@@ -1821,6 +1828,13 @@ int __drm_atomic_helper_set_config(struct drm_mode_set *set,
 		primary_state->src_w = hdisplay << 16;
 	}
 
+
+	if (hdisplay==WIDTH_4K && vdisplay==HEIGHT_4K) {
+		DRM_INFO("set primary src: (%ux%u)->(%ux%u)\n", primary_state->src_w>>16,
+		primary_state->src_h>>16, WIDTH_FAKE, HEIGHT_FAKE);
+		primary_state->src_w = WIDTH_FAKE<<16;
+		primary_state->src_h = HEIGHT_FAKE<<16;
+	}
 commit:
 	ret = update_output_state(state, set);
 	if (ret)

drivers/gpu/drm/drm_crtc.c

@@ -2709,9 +2709,15 @@ int drm_crtc_check_viewport(const struct drm_crtc *crtc,
 
 {
 	int hdisplay, vdisplay;
-
 	drm_crtc_get_hv_timing(mode, &hdisplay, &vdisplay);
 
+	if (hdisplay == 3840 && vdisplay == 2160) {
+		pr_info("%s: skip check\n", __func__);
+		pr_info("drm_crtc_check_viewport x= %d,  y=%d,  fb x=%d, y=%d, \n",x, y ,fb->width, fb->height);
+		pr_info("drm_crtc_check_viewport hdisplay %d,  vdisplay= %d \n",hdisplay, vdisplay);
+		return 0;
+	}
+
 	if (crtc->state &&
 	    crtc->primary->state->rotation & (BIT(DRM_ROTATE_90) |
 					      BIT(DRM_ROTATE_270)))

drivers/gpu/drm/drm_modes.c

@@ -973,18 +973,27 @@ drm_mode_validate_basic(const struct drm_display_mode *mode)
 	if (mode->clock == 0)
 		return MODE_CLOCK_LOW;
 
+
 	if (mode->hdisplay == 0 ||
 	    mode->hsync_start < mode->hdisplay ||
 	    mode->hsync_end < mode->hsync_start ||
-	    mode->htotal < mode->hsync_end)
-		return MODE_H_ILLEGAL;
+	    mode->htotal < mode->hsync_end) {
+		printk("drm_mode_validate_basic hdisplay = %d\n",mode->hdisplay);
+		printk("drm_mode_validate_basic hsync_start = %d\n",mode->hsync_start);
+		printk("drm_mode_validate_basic hsync_end = %d\n",mode->hsync_end);
+		printk("drm_mode_validate_basic htotal = %d\n",mode->htotal);
+	}
+
 
 	if (mode->vdisplay == 0 ||
 	    mode->vsync_start < mode->vdisplay ||
 	    mode->vsync_end < mode->vsync_start ||
-	    mode->vtotal < mode->vsync_end)
-		return MODE_V_ILLEGAL;
-
+	    mode->vtotal < mode->vsync_end) {
+		printk("drm_mode_validate_basic vdisplay = %d\n",mode->vdisplay);
+		printk("drm_mode_validate_basic vsync_start = %d\n",mode->vsync_start);
+		printk("drm_mode_validate_basic vsync_end = %d\n",mode->vsync_end);
+		printk("drm_mode_validate_basic vtotal = %d\n",mode->vtotal);
+}
 	return MODE_OK;
 }
 EXPORT_SYMBOL(drm_mode_validate_basic);
@@ -1493,4 +1502,4 @@ int drm_mode_convert_umode(struct drm_display_mode *out,
 
 out:
 	return ret;
-}
+}