openwrt/target/linux/bcm27xx/patches-5.10/950-0538-drm-vc4-hdmi-Convert-to-the-new-clock-request-API.patch

From fe77a92b9018f9a2dbab0e2a600e368d55c667b0 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime@cerno.tech>
Date: Tue, 13 Apr 2021 11:55:55 +0200
Subject: [PATCH] drm/vc4: hdmi: Convert to the new clock request API

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@cerno.tech>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 22 +++++++++++++++-------
 drivers/gpu/drm/vc4/vc4_hdmi.h |  3 +++
 2 files changed, 18 insertions(+), 7 deletions(-)

--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -546,6 +546,9 @@ static void vc4_hdmi_encoder_post_crtc_p
 		   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);
@@ -850,9 +853,9 @@ static void vc4_hdmi_encoder_pre_crtc_co
 	 * 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;
 	}
 
@@ -864,10 +867,12 @@ static void vc4_hdmi_encoder_pre_crtc_co
 	 * 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;
 	}
@@ -875,6 +880,9 @@ static void vc4_hdmi_encoder_pre_crtc_co
 	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;
 	}
--- a/drivers/gpu/drm/vc4/vc4_hdmi.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
@@ -172,6 +172,9 @@ struct vc4_hdmi {
 
 	struct reset_control *reset;
 
+	struct clk_request *bvb_req;
+	struct clk_request *hsm_req;
+
 	/* Common debugfs regset */
 	struct debugfs_regset32 hdmi_regset;
 	struct debugfs_regset32 hd_regset;