[PATCH 2/2] drm/vc4: hdmi: Convert to the new clock request API

Maxime Ripard maxime at cerno.tech
Tue Apr 13 10:13:20 UTC 2021


The new clock request API allows us to increase the rate of the HSM
clock to match our pixel rate requirements while decreasing it when
we're done, resulting in a better power-efficiency.

Signed-off-by: Maxime Ripard <maxime at cerno.tech>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 19 ++++++++++++-------
 drivers/gpu/drm/vc4/vc4_hdmi.h |  3 +++
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 1fda574579af..244053de6150 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -473,7 +473,9 @@ static void vc4_hdmi_encoder_post_crtc_powerdown(struct drm_encoder *encoder,
 		   HDMI_READ(HDMI_VID_CTL) & ~VC4_HD_VID_CTL_ENABLE);
 
 	clk_disable_unprepare(vc4_hdmi->pixel_bvb_clock);
+	clk_request_done(vc4_hdmi->bvb_req);
 	clk_disable_unprepare(vc4_hdmi->hsm_clock);
+	clk_request_done(vc4_hdmi->hsm_req);
 	clk_disable_unprepare(vc4_hdmi->pixel_clock);
 
 	ret = pm_runtime_put(&vc4_hdmi->pdev->dev);
@@ -778,9 +780,9 @@ static void vc4_hdmi_encoder_pre_crtc_configure(struct drm_encoder *encoder,
 	 * pixel clock, but HSM ends up being the limiting factor.
 	 */
 	hsm_rate = max_t(unsigned long, 120000000, (pixel_rate / 100) * 101);
-	ret = clk_set_min_rate(vc4_hdmi->hsm_clock, hsm_rate);
-	if (ret) {
-		DRM_ERROR("Failed to set HSM clock rate: %d\n", ret);
+	vc4_hdmi->hsm_req = clk_request_start(vc4_hdmi->hsm_clock, hsm_rate);
+	if (IS_ERR(vc4_hdmi->hsm_req)) {
+		DRM_ERROR("Failed to set HSM clock rate: %ld\n", PTR_ERR(vc4_hdmi->hsm_req));
 		return;
 	}
 
@@ -797,10 +799,11 @@ static void vc4_hdmi_encoder_pre_crtc_configure(struct drm_encoder *encoder,
 	 * FIXME: When the pixel freq is 594MHz (4k60), this needs to be setup
 	 * at 300MHz.
 	 */
-	ret = clk_set_min_rate(vc4_hdmi->pixel_bvb_clock,
-			       (hsm_rate > VC4_HSM_MID_CLOCK ? 150000000 : 75000000));
-	if (ret) {
-		DRM_ERROR("Failed to set pixel bvb clock rate: %d\n", ret);
+	vc4_hdmi->bvb_req = clk_request_start(vc4_hdmi->pixel_bvb_clock,
+					      (hsm_rate > VC4_HSM_MID_CLOCK ? 150000000 : 75000000));
+	if (IS_ERR(vc4_hdmi->bvb_req)) {
+		DRM_ERROR("Failed to set pixel bvb clock rate: %ld\n", PTR_ERR(vc4_hdmi->bvb_req));
+		clk_request_done(vc4_hdmi->hsm_req);
 		clk_disable_unprepare(vc4_hdmi->hsm_clock);
 		clk_disable_unprepare(vc4_hdmi->pixel_clock);
 		return;
@@ -809,6 +812,8 @@ static void vc4_hdmi_encoder_pre_crtc_configure(struct drm_encoder *encoder,
 	ret = clk_prepare_enable(vc4_hdmi->pixel_bvb_clock);
 	if (ret) {
 		DRM_ERROR("Failed to turn on pixel bvb clock: %d\n", ret);
+		clk_request_done(vc4_hdmi->bvb_req);
+		clk_request_done(vc4_hdmi->hsm_req);
 		clk_disable_unprepare(vc4_hdmi->hsm_clock);
 		clk_disable_unprepare(vc4_hdmi->pixel_clock);
 		return;
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h
index 3cebd1fd00fc..9ac4a2c751df 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
@@ -167,6 +167,9 @@ struct vc4_hdmi {
 
 	struct reset_control *reset;
 
+	struct clk_request *bvb_req;
+	struct clk_request *hsm_req;
+
 	struct debugfs_regset32 hdmi_regset;
 	struct debugfs_regset32 hd_regset;
 };
-- 
2.30.2



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