From 7c3fc2b5ccd6694b48c2226704e25fad7acc6976 Mon Sep 17 00:00:00 2001
From: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Date: Tue, 27 Sep 2016 17:59:56 +0200
Subject: [PATCH] drm/exynos: g2d: use autosuspend mode for PM runtime

The runqueue worker currently issues a get() when a new
node is processed, and a put() once a node is completed.

The corresponding suspend and resume calls currently only
do clock gating, but with the upcoming introduction of
IOMMU runpm also the corresponding IOMMU domain gets
enabled (for get()) and disabled (for put()). This
introduces performance regressions with we mitigate here.

Switch PM runtime to autosuspend, such that clock gating
and IOMMU control only happens when the engine is idle for
a 'long' time.

Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
---
 drivers/gpu/drm/exynos/exynos_drm_g2d.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_g2d.c b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
index 94fb9d2f90c1..1f0bcff69737 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_g2d.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
@@ -903,7 +903,8 @@ static void g2d_runqueue_worker(struct work_struct *work)
 	g2d->runqueue_node = NULL;
 
 	if (runqueue_node) {
-		pm_runtime_put(g2d->dev);
+		pm_runtime_mark_last_busy(g2d->dev);
+		pm_runtime_put_autosuspend(g2d->dev);
 
 		complete(&runqueue_node->complete);
 		if (runqueue_node->async)
@@ -1022,7 +1023,8 @@ static void g2d_wait_finish(struct g2d_data *g2d, struct drm_file *file)
 	 * the IRQ which triggers the PM runtime put().
 	 * So do this manually here.
 	 */
-	pm_runtime_put(dev);
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
 
 	complete(&runqueue_node->complete);
 	if (runqueue_node->async)
@@ -1519,6 +1521,8 @@ static int g2d_probe(struct platform_device *pdev)
 		goto err_destroy_workqueue;
 	}
 
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_set_autosuspend_delay(dev, 2000);
 	pm_runtime_enable(dev);
 	clear_bit(G2D_BIT_SUSPEND_RUNQUEUE, &g2d->flags);
 	clear_bit(G2D_BIT_ENGINE_BUSY, &g2d->flags);
@@ -1590,6 +1594,7 @@ static int g2d_remove(struct platform_device *pdev)
 	/* There should be no locking needed here. */
 	g2d_remove_runqueue_nodes(g2d, NULL);
 
+	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 
 	g2d_fini_cmdlist(g2d);
-- 
GitLab