Don't change the blank/sync width when calculating scaled modes

Don't the change the blank/vsync width while doing LVDS scaled modes.
And use the border instead of border minus one.

At the same time, make sure the horizontal border and hsync are even for
the LVDS that works in dual-channel mode. So both horizontal border and hsync
start are also changed to be even, even for the LVDS in single-channel
mode.

https://bugs.freedesktop.org/show_bug.cgi?id=20951

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>

1 files changed, 62 insertions, 21 deletions

diff --git a/src/i830_lvds.c b/src/i830_lvds.c
index 064810f6..aefe069f 100644
--- a/src/i830_lvds.c
+++ b/src/i830_lvds.c
@@ -607,6 +607,9 @@ i830_lvds_mode_fixup(xf86OutputPtr output, DisplayModePtr mode,
     float		    horiz_ratio, vert_ratio;
     int left_border = 0, right_border = 0, top_border = 0, bottom_border = 0;
     int i;
+    uint32_t		    hsync_width, vsync_width;
+    uint32_t		    hblank_width, vblank_width;
+    uint32_t		    hsync_pos, vsync_pos;
     Bool border = 0;
 
     for (i = 0; i < xf86_config->num_output; i++) {
@@ -663,6 +666,12 @@ i830_lvds_mode_fixup(xf86OutputPtr output, DisplayModePtr mode,
 	pfit_control |= (intel_crtc->pipe << PFIT_PIPE_SHIFT) |
 	    PFIT_FILTER_FUZZY;
 
+    hsync_width = adjusted_mode->CrtcHSyncEnd - adjusted_mode->CrtcHSyncStart;
+    vsync_width = adjusted_mode->CrtcVSyncEnd - adjusted_mode->CrtcVSyncStart;
+    hblank_width = adjusted_mode->CrtcHBlankEnd -
+					adjusted_mode->CrtcHBlankStart;
+    vblank_width = adjusted_mode->CrtcVBlankEnd -
+					adjusted_mode->CrtcVBlankStart;
     /*
      * Deal with panel fitting options.  Figure out how to stretch the image
      * based on its aspect ratio & the current panel fitting mode.
@@ -700,17 +709,34 @@ i830_lvds_mode_fixup(xf86OutputPtr output, DisplayModePtr mode,
 
 	/* Set active & border values */
 	adjusted_mode->CrtcHDisplay = mode->HDisplay;
-	adjusted_mode->CrtcHBlankStart = mode->HDisplay + right_border - 1;
-	adjusted_mode->CrtcHBlankEnd = adjusted_mode->CrtcHTotal -
-	    left_border - 1;
-	adjusted_mode->CrtcHSyncStart = adjusted_mode->CrtcHBlankStart;
-	adjusted_mode->CrtcHSyncEnd = adjusted_mode->CrtcHBlankEnd;
+	/* keep the horizontal border be even */
+	if (right_border & 1)
+		right_border++;
+	/* use the border directly instead of border minus one */
+	adjusted_mode->CrtcHBlankStart = mode->HDisplay + right_border;
+	/* keep the blank width constant */
+	adjusted_mode->CrtcHBlankEnd = adjusted_mode->CrtcHBlankStart +
+					hblank_width;
+	/* get the hsync start position relative to hblank start */
+	hsync_pos = (hblank_width - hsync_width) / 2;
+	/* keep the hsync width constant and hsync start be even */
+	if (hsync_pos & 1)
+		hsync_pos++;
+	adjusted_mode->CrtcHSyncStart = adjusted_mode->CrtcHBlankStart +
+						hsync_pos;
+	adjusted_mode->CrtcHSyncEnd = adjusted_mode->CrtcHSyncStart +
+						hsync_width;
 	adjusted_mode->CrtcVDisplay = mode->VDisplay;
-	adjusted_mode->CrtcVBlankStart = mode->VDisplay + bottom_border - 1;
-	adjusted_mode->CrtcVBlankEnd = adjusted_mode->CrtcVTotal -
-	    top_border - 1;
-	adjusted_mode->CrtcVSyncStart = adjusted_mode->CrtcVBlankStart;
-	adjusted_mode->CrtcVSyncEnd = adjusted_mode->CrtcVBlankEnd;
+	/* use the border instead of border minus one */
+	adjusted_mode->CrtcVBlankStart = mode->VDisplay + bottom_border;
+	adjusted_mode->CrtcVBlankEnd = adjusted_mode->CrtcVBlankStart +
+						vblank_width;
+	/* get the vsync start position relative to vblank start */
+	vsync_pos = (vblank_width - vsync_width) / 2;
+	adjusted_mode->CrtcVSyncStart = adjusted_mode->CrtcVBlankStart +
+						vsync_pos;
+	adjusted_mode->CrtcVSyncEnd = adjusted_mode->CrtcVSyncStart +
+						vsync_width;
 	border = 1;
 	break;
     case FULL_ASPECT:
@@ -758,13 +784,22 @@ i830_lvds_mode_fixup(xf86OutputPtr output, DisplayModePtr mode,
 		if (mode->HDisplay & 1) /* odd resolutions */
 		    right_border++;
 
+		/* keep the border be even */
+		if (right_border & 1)
+			right_border++;
 		adjusted_mode->CrtcHDisplay = scaled_width;
-		adjusted_mode->CrtcHBlankStart = scaled_width +
-		    right_border - 1;
-		adjusted_mode->CrtcHBlankEnd = adjusted_mode->CrtcHTotal -
-		    left_border - 1;
-		adjusted_mode->CrtcHSyncStart = adjusted_mode->CrtcHBlankStart;
-		adjusted_mode->CrtcHSyncEnd = adjusted_mode->CrtcHBlankEnd;
+		adjusted_mode->CrtcHBlankStart = scaled_width + right_border;
+		adjusted_mode->CrtcHBlankEnd = adjusted_mode->CrtcHBlankStart +
+							hblank_width;
+		/* get the hsync start position relative to hblank start */
+		hsync_pos = (hblank_width - hsync_width) / 2;
+		/* keep the hsync start be even */
+		if (hsync_pos & 1)
+			hsync_pos++;
+		adjusted_mode->CrtcHSyncStart = adjusted_mode->CrtcHBlankStart +
+							hsync_pos;
+		adjusted_mode->CrtcHSyncEnd = adjusted_mode->CrtcHSyncStart +
+							hsync_width;
 		border = 1;
 	    } else if (panel_ratio < desired_ratio) { /* Letter */
 		unsigned long scaled_height = (float)mode->VDisplay *
@@ -782,12 +817,18 @@ i830_lvds_mode_fixup(xf86OutputPtr output, DisplayModePtr mode,
 		    bottom_border++;
 
 		adjusted_mode->CrtcVDisplay = scaled_height;
+		/* use the border instead of border minus one */
 		adjusted_mode->CrtcVBlankStart = scaled_height +
-		    bottom_border - 1;
-		adjusted_mode->CrtcVBlankEnd = adjusted_mode->CrtcVTotal -
-		    top_border - 1;
-		adjusted_mode->CrtcVSyncStart = adjusted_mode->CrtcVBlankStart;
-		adjusted_mode->CrtcVSyncEnd = adjusted_mode->CrtcVBlankEnd;
+		    bottom_border;
+		/* keep the Vblank width constant */
+		adjusted_mode->CrtcVBlankEnd = adjusted_mode->CrtcVBlankStart +
+							vblank_width;
+		/* get the vsync start position relative to vblank start */
+		vsync_pos = (vblank_width - vsync_width) / 2;
+		adjusted_mode->CrtcVSyncStart = adjusted_mode->CrtcVBlankStart +
+							vsync_pos;
+		adjusted_mode->CrtcVSyncEnd = adjusted_mode->CrtcVBlankStart +
+							vsync_width;
 		border = 1;
 	    } else { /* Aspects match, let hw scale both directions */
 		pfit_control |= VERT_AUTO_SCALE | HORIZ_AUTO_SCALE |