From: Dave Airlie <airlied@redhat.com>
Date: Tue, 21 Jan 2014 06:47:46 +0000 (-0500)
Subject: drm/mgag200: on cards with < 2MB VRAM default to 16-bit
X-Git-Tag: upstream/snapshot3+hdmi~3525^2~11
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=918be888d613e58938338b4b0c895de97579173d;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git

drm/mgag200: on cards with < 2MB VRAM default to 16-bit

This aligns with what the userspace -mga driver does in
the same situation.

Signed-off-by: Dave Airlie <airlied@redhat.com>
---

diff --git a/drivers/gpu/drm/mgag200/mgag200_fb.c b/drivers/gpu/drm/mgag200/mgag200_fb.c
index 964f58c..005b60a 100644
--- a/drivers/gpu/drm/mgag200/mgag200_fb.c
+++ b/drivers/gpu/drm/mgag200/mgag200_fb.c
@@ -282,6 +282,11 @@ int mgag200_fbdev_init(struct mga_device *mdev)
 {
 	struct mga_fbdev *mfbdev;
 	int ret;
+	int bpp_sel = 32;
+
+	/* prefer 16bpp on low end gpus with limited VRAM */
+	if (IS_G200_SE(mdev) && mdev->mc.vram_size < (2048*1024))
+		bpp_sel = 16;
 
 	mfbdev = devm_kzalloc(mdev->dev->dev, sizeof(struct mga_fbdev), GFP_KERNEL);
 	if (!mfbdev)
@@ -301,7 +306,7 @@ int mgag200_fbdev_init(struct mga_device *mdev)
 	/* disable all the possible outputs/crtcs before entering KMS mode */
 	drm_helper_disable_unused_functions(mdev->dev);
 
-	drm_fb_helper_initial_config(&mfbdev->helper, 32);
+	drm_fb_helper_initial_config(&mfbdev->helper, bpp_sel);
 
 	return 0;
 }
diff --git a/drivers/gpu/drm/mgag200/mgag200_main.c b/drivers/gpu/drm/mgag200/mgag200_main.c
index a1bfe72..26868e5 100644
--- a/drivers/gpu/drm/mgag200/mgag200_main.c
+++ b/drivers/gpu/drm/mgag200/mgag200_main.c
@@ -217,7 +217,10 @@ int mgag200_driver_load(struct drm_device *dev, unsigned long flags)
 
 	drm_mode_config_init(dev);
 	dev->mode_config.funcs = (void *)&mga_mode_funcs;
-	dev->mode_config.preferred_depth = 24;
+	if (IS_G200_SE(mdev) && mdev->mc.vram_size < (2048*1024))
+		dev->mode_config.preferred_depth = 16;
+	else
+		dev->mode_config.preferred_depth = 24;
 	dev->mode_config.prefer_shadow = 1;
 
 	r = mgag200_modeset_init(mdev);