video: tegra: dc: rewrite bandwidth formula

Take vertical scaling into account when calculating
a window's bandwidth, if the window supports
filtering.

Change-Id: Ie0816706322699c3c48bdde31372928972412b74
Signed-off-by: Jon Mayo <jmayo@nvidia.com>
Reviewed-on: http://git-master/r/242567
(cherry picked from commit 0bf3d1ea973a062f0017b26a28d1804dccf9d7e4)
Reviewed-on: http://git-master/r/247514
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Min-wuk Lee <mlee@nvidia.com>
Reviewed-by: Youngjin Kim <nkim@nvidia.com>
Tested-by: Harry Hong <hhong@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Gabby Lee <galee@nvidia.com>

1 files changed, 36 insertions, 17 deletions

diff --git a/drivers/video/tegra/dc/bandwidth.c b/drivers/video/tegra/dc/bandwidth.c
index 789f7f03facf..4989ba4d096c 100644
--- a/drivers/video/tegra/dc/bandwidth.c
+++ b/drivers/video/tegra/dc/bandwidth.c
@@ -174,23 +174,28 @@ static unsigned long tegra_dc_find_max_bandwidth(struct tegra_dc_win *wins[],
 static unsigned long tegra_dc_calc_win_bandwidth(struct tegra_dc *dc,
 	struct tegra_dc_win *w)
 {
-	unsigned long ret;
-	int tiled_windows_bw_multiplier;
-	unsigned long bpp;
 	unsigned in_w;
+	unsigned in_h;
+	unsigned bpp;
+	unsigned long f_w;
+	unsigned long f_h;
+	unsigned long bw;
+	int tiled_windows_bw_multiplier;
 
-	if (!WIN_IS_ENABLED(w))
+	/* ignore windows that are off or invalid */
+	if (!WIN_IS_ENABLED(w) || dfixed_trunc(w->w) == 0 ||
+		dfixed_trunc(w->h) == 0 || w->out_w == 0 || w->out_h == 0)
 		return 0;
 
-	if (dfixed_trunc(w->w) == 0 || dfixed_trunc(w->h) == 0 ||
-	    w->out_w == 0 || w->out_h == 0)
-		return 0;
-	if (w->flags & TEGRA_WIN_FLAG_SCAN_COLUMN)
-		/* rotated: PRESCALE_SIZE swapped, but WIN_SIZE is unchanged */
+	if (w->flags & TEGRA_WIN_FLAG_SCAN_COLUMN) {
+		/* rotated : prescaled size is swapped */
 		in_w = dfixed_trunc(w->h);
-	else
-		in_w = dfixed_trunc(w->w); /* normal output, not rotated */
-
+		in_h = dfixed_trunc(w->w);
+	} else {
+		/* normal */
+		in_w = dfixed_trunc(w->w);
+		in_h = dfixed_trunc(w->h);
+	}
 	tiled_windows_bw_multiplier =
 		tegra_mc_get_tiled_memory_bandwidth_multiplier();
 
@@ -199,14 +204,28 @@ static unsigned long tegra_dc_calc_win_bandwidth(struct tegra_dc *dc,
 	 * is of the luma plane's size only. */
 	bpp = tegra_dc_is_yuv_planar(w->fmt) ?
 		2 * tegra_dc_fmt_bpp(w->fmt) : tegra_dc_fmt_bpp(w->fmt);
-	ret = dc->mode.pclk / 1000UL * bpp / 8 *
+
+	bw = dc->mode.pclk / 1000UL * bpp / 8;
+
+	if (WIN_IS_TILED(w))
+		bw *= tiled_windows_bw_multiplier;
+
 #if defined(CONFIG_ARCH_TEGRA_2x_SOC) || defined(CONFIG_ARCH_TEGRA_3x_SOC)
-		(win_use_v_filter(dc, w) ? 2 : 1) *
+	if (win_use_v_filter(dc, w))
+		bw *= 2;
 #endif
-		in_w / w->out_w * (WIN_IS_TILED(w) ?
-		tiled_windows_bw_multiplier : 1);
 
-	return ret;
+	/* calculate H & V scaling factor. treat upscaling as 1.00 */
+	f_w = max(in_w * 100 / w->out_w, 100u);
+	f_h = max(in_h * 100 / w->out_h, 100u);
+	bw *= f_w;
+	bw /= 100;
+	if (win_use_v_filter(dc, w)) {
+		bw *= f_h;
+		bw /= 100;
+	}
+
+	return bw;
 }
 
 static unsigned long tegra_dc_get_bandwidth(