video: tegra: dc: skip duplicate CMU update

Skip updating CMU on first boot, and restore CMU after disable or
suspend. Use dc->pdata->cmu_enable to select initial state of cmu, and
move the current cmu status out of dc->pdata and into dc->cmu_enabled.
Remove unused flag TEGRA_DC_FLAG_CMU_ENABLE.

Bug 1507065

Reviewed-on: http://git-master/r/410636
(cherry picked from commit 0c0bfb40e67fb31a01bd69695e0f153dbb2ac8de)

Change-Id: I645923339653698d1be137b3b90ad38735c3159e
Signed-off-by: Jon Mayo <jmayo@nvidia.com>
Reviewed-on: http://git-master/r/431945
Reviewed-by: Mitch Luban <mluban@nvidia.com>
Tested-by: Mitch Luban <mluban@nvidia.com>
Reviewed-by: Automatic_Commit_Validation_User

2 files changed, 37 insertions, 25 deletions

diff --git a/drivers/video/tegra/dc/dc.c b/drivers/video/tegra/dc/dc.c
index fc1d80abb3f5..cd5057752e70 100644
--- a/drivers/video/tegra/dc/dc.c
+++ b/drivers/video/tegra/dc/dc.c
@@ -1091,10 +1091,12 @@ static void tegra_dc_set_scaling_filter(struct tegra_dc *dc)
 }
 
 #ifdef CONFIG_TEGRA_DC_CMU
-static void tegra_dc_cache_cmu(struct tegra_dc_cmu *dst_cmu,
+static void tegra_dc_cache_cmu(struct tegra_dc *dc,
 					struct tegra_dc_cmu *src_cmu)
 {
-	memcpy(dst_cmu, src_cmu, sizeof(struct tegra_dc_cmu));
+	if (&dc->cmu != src_cmu) /* ignore if it would require memmove() */
+		memcpy(&dc->cmu, src_cmu, sizeof(*src_cmu));
+	dc->cmu_dirty = true;
 }
 
 static void tegra_dc_set_cmu(struct tegra_dc *dc, struct tegra_dc_cmu *cmu)
@@ -1121,45 +1123,40 @@ static void tegra_dc_set_cmu(struct tegra_dc *dc, struct tegra_dc_cmu *cmu)
 		val = LUT2_ADDR(i) | LUT1_DATA(cmu->lut2[i]);
 		tegra_dc_writel(dc, val, DC_COM_CMU_LUT2);
 	}
+
+	dc->cmu_dirty = false;
 }
 
-int _tegra_dc_update_cmu(struct tegra_dc *dc, struct tegra_dc_cmu *cmu)
+static void _tegra_dc_update_cmu(struct tegra_dc *dc, struct tegra_dc_cmu *cmu)
 {
 	u32 val;
 
-	if (dc->pdata->cmu_enable) {
-		dc->pdata->flags |= TEGRA_DC_FLAG_CMU_ENABLE;
-	} else {
-		dc->pdata->flags &= ~TEGRA_DC_FLAG_CMU_ENABLE;
-		return 0;
-	}
+	if (!dc->cmu_enabled)
+		return;
 
-#ifdef CONFIG_TEGRA_DC_CMU
-	if (memcmp(cmu, &dc->cmu, sizeof(struct tegra_dc_cmu))) {
-		tegra_dc_cache_cmu(&dc->cmu, cmu);
+	tegra_dc_cache_cmu(dc, cmu);
 
-		/* Disable CMU */
+	if (dc->cmu_dirty) {
+		/* Disable CMU to avoid programming it while it is in use */
 		val = tegra_dc_readl(dc, DC_DISP_DISP_COLOR_CONTROL);
 		if (val & CMU_ENABLE) {
 			val &= ~CMU_ENABLE;
-			tegra_dc_writel(dc, val, DC_DISP_DISP_COLOR_CONTROL);
+			tegra_dc_writel(dc, val,
+					DC_DISP_DISP_COLOR_CONTROL);
 			val = GENERAL_ACT_REQ;
 			tegra_dc_writel(dc, val, DC_CMD_STATE_CONTROL);
 			/*TODO: Sync up with vsync */
 			mdelay(20);
 		}
+		dev_dbg(&dc->ndev->dev, "updating CMU cmu_dirty=%d\n",
+			dc->cmu_dirty);
 
 		tegra_dc_set_cmu(dc, &dc->cmu);
 	}
-#endif
-
-	return 0;
 }
 
 int tegra_dc_update_cmu(struct tegra_dc *dc, struct tegra_dc_cmu *cmu)
 {
-	int ret;
-
 	mutex_lock(&dc->lock);
 	if (!dc->enabled) {
 		mutex_unlock(&dc->lock);
@@ -1168,13 +1165,13 @@ int tegra_dc_update_cmu(struct tegra_dc *dc, struct tegra_dc_cmu *cmu)
 
 	tegra_dc_get(dc);
 
-	ret = _tegra_dc_update_cmu(dc, cmu);
+	_tegra_dc_update_cmu(dc, cmu);
 	tegra_dc_set_color_control(dc);
 
 	tegra_dc_put(dc);
 	mutex_unlock(&dc->lock);
 
-	return ret;
+	return 0;
 }
 EXPORT_SYMBOL(tegra_dc_update_cmu);
 
@@ -1190,11 +1187,11 @@ static struct tegra_dc_cmu *tegra_dc_get_cmu(struct tegra_dc *dc)
 
 void tegra_dc_cmu_enable(struct tegra_dc *dc, bool cmu_enable)
 {
-	dc->pdata->cmu_enable = cmu_enable;
+	dc->cmu_enabled = cmu_enable;
 	tegra_dc_update_cmu(dc, tegra_dc_get_cmu(dc));
 }
 #else
-#define tegra_dc_cache_cmu(dst_cmu, src_cmu)
+#define tegra_dc_cache_cmu(dc, src_cmu)
 #define tegra_dc_set_cmu(dc, cmu)
 #define tegra_dc_update_cmu(dc, cmu)
 #endif
@@ -1411,7 +1408,7 @@ static int tegra_dc_set_out(struct tegra_dc *dc, struct tegra_dc_out *out)
 		 * read them, but unfortunately there is no reliable and
 		 * flicker-free way to do this!
 		 */
-		tegra_dc_cache_cmu(&dc->cmu, tegra_dc_get_cmu(dc));
+		tegra_dc_cache_cmu(dc, tegra_dc_get_cmu(dc));
 #endif
 	} else if (out->n_modes > 0)
 		tegra_dc_set_mode(dc, &dc->out->modes[0]);
@@ -2112,7 +2109,7 @@ void tegra_dc_set_color_control(struct tegra_dc *dc)
 	}
 
 #ifdef CONFIG_TEGRA_DC_CMU
-	if (dc->pdata->flags & TEGRA_DC_FLAG_CMU_ENABLE)
+	if (dc->cmu_enabled)
 		color_control |= CMU_ENABLE;
 #endif
 
@@ -2646,6 +2643,12 @@ int tegra_dc_restore(struct tegra_dc *dc)
 
 static void _tegra_dc_disable(struct tegra_dc *dc)
 {
+#ifdef CONFIG_TEGRA_DC_CMU
+	/* power down resets the registers, setting to true
+	 * causes CMU to be restored in tegra_dc_init(). */
+	dc->cmu_dirty = true;
+#endif
+
 	if (dc->out->flags & TEGRA_DC_OUT_ONE_SHOT_MODE) {
 		mutex_lock(&dc->one_shot_lock);
 		cancel_delayed_work_sync(&dc->one_shot_work);
@@ -3138,6 +3141,12 @@ static int tegra_dc_probe(struct platform_device *ndev)
 	pm_runtime_set_autosuspend_delay(&ndev->dev, 100);
 	pm_runtime_enable(&ndev->dev);
 
+#ifdef CONFIG_TEGRA_DC_CMU
+	/* if bootloader leaves this head enabled, then skip CMU programming. */
+	dc->cmu_dirty = (dc->pdata->flags & TEGRA_DC_FLAG_ENABLED) == 0;
+	dc->cmu_enabled = dc->pdata->cmu_enable;
+#endif
+
 	if (dc->pdata->flags & TEGRA_DC_FLAG_ENABLED) {
 		_tegra_dc_set_default_videomode(dc);
 		dc->enabled = _tegra_dc_enable(dc);
@@ -3434,6 +3443,7 @@ static int tegra_dc_resume(struct platform_device *ndev)
 
 	if (dc->out_ops && dc->out_ops->resume)
 		dc->out_ops->resume(dc);
+
 	mutex_unlock(&dc->lock);
 
 	return 0;
diff --git a/drivers/video/tegra/dc/dc_priv_defs.h b/drivers/video/tegra/dc/dc_priv_defs.h
index fce904cc1d80..230d8093d196 100644
--- a/drivers/video/tegra/dc/dc_priv_defs.h
+++ b/drivers/video/tegra/dc/dc_priv_defs.h
@@ -168,6 +168,8 @@ struct tegra_dc {
 	int				n_windows;
 #ifdef CONFIG_TEGRA_DC_CMU
 	struct tegra_dc_cmu		cmu;
+	bool				cmu_dirty;
+	bool				cmu_enabled;
 #endif
 	wait_queue_head_t		wq;
 	wait_queue_head_t		timestamp_wq;