drm/mgag200: Fix to always set HiPri for G200e4 V2

  - Changed the HiPri value for G200e4 to always be 0.
  - Added Bandwith limitation to block resolution above 1920x1200x60Hz

Signed-off-by: Mathieu Larouche <mathieu.larouche@matrox.com>
Acked-by: Dave Airlie <airlied@redhat.com>
[seanpaul removed some trailing whitespace from the patch]
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/ec0f8568d7ec41904dfe593c5deccf3f062d7bd8.1497450944.git.mathieu.larouche@matrox.com

drivers/gpu/drm/mgag200/mgag200_mode.c

@@ -1173,7 +1173,10 @@ static int mga_crtc_mode_set(struct drm_crtc *crtc,
 
 
 	if (IS_G200_SE(mdev)) {
-		if (mdev->unique_rev_id >= 0x02) {
+		if  (mdev->unique_rev_id >= 0x04) {
+			WREG8(MGAREG_CRTCEXT_INDEX, 0x06);
+			WREG8(MGAREG_CRTCEXT_DATA, 0);
+		} else if (mdev->unique_rev_id >= 0x02) {
 			u8 hi_pri_lvl;
 			u32 bpp;
 			u32 mb;
@@ -1639,6 +1642,10 @@ static int mga_vga_mode_valid(struct drm_connector *connector,
 			if (mga_vga_calculate_mode_bandwidth(mode, bpp)
 				> (30100 * 1024))
 				return MODE_BANDWIDTH;
+		} else {
+			if (mga_vga_calculate_mode_bandwidth(mode, bpp)
+				> (55000 * 1024))
+				return MODE_BANDWIDTH;
 		}
 	} else if (mdev->type == G200_WB) {
 		if (mode->hdisplay > 1280)