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 <[email protected]>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 15 ++++++++++-----
 drivers/gpu/drm/vc4/vc4_hdmi.h |  3 +++
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 4a1115043114..099a94570e86 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -635,6 +635,8 @@ static void vc4_hdmi_encoder_post_crtc_powerdown(struct 
drm_encoder *encoder,
                vc4_hdmi->variant->phy_disable(vc4_hdmi);
 
        clk_disable_unprepare(vc4_hdmi->pixel_bvb_clock);
+       clk_request_done(vc4_hdmi->bvb_req);
+       clk_request_done(vc4_hdmi->hsm_req);
        clk_disable_unprepare(vc4_hdmi->pixel_clock);
 
        ret = pm_runtime_put(&vc4_hdmi->pdev->dev);
@@ -941,9 +943,9 @@ 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;
        }
 
@@ -956,9 +958,10 @@ static void vc4_hdmi_encoder_pre_crtc_configure(struct 
drm_encoder *encoder,
        else
                bvb_rate = 75000000;
 
-       ret = clk_set_min_rate(vc4_hdmi->pixel_bvb_clock, bvb_rate);
+       vc4_hdmi->bvb_req = clk_request_start(vc4_hdmi->pixel_bvb_clock, 
bvb_rate);
        if (ret) {
-               DRM_ERROR("Failed to set pixel bvb clock rate: %d\n", ret);
+               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->pixel_clock);
                return;
        }
@@ -966,6 +969,8 @@ 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->pixel_clock);
                return;
        }
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h
index 33e9f665ab8e..683b2d8a3dca 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
@@ -176,6 +176,9 @@ 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;
 };
-- 
2.31.1

Reply via email to