[PATCH v5 10/11] drm/vc4: Add logging and comments

Maxime Ripard
2022-02-22T13:19:23Z

The HVS core clock isn't really obvious, so let's add a bunch more
comments and some logging for easier debugging.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/gpu/drm/vc4/vc4_kms.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c
index 24de29bc1cda..6fe03fc17d73 100644
--- a/drivers/gpu/drm/vc4/vc4_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_kms.c
@@ -389,8 +389,15 @@ static void vc4_atomic_commit_tail(struct drm_atomic_state *state)
500000000,
new_hvs_state->core_clock_rate);

+ drm_dbg(dev, "Raising the core clock at %lu Hz\n", core_rate);
+
+ /*
+ * Do a temporary request on the core clock during the
+ * modeset.
+ */
clk_set_min_rate(hvs->core_clk, core_rate);
}
+
drm_atomic_helper_commit_modeset_disables(dev, state);

vc4_ctm_commit(vc4, state);
@@ -416,6 +423,10 @@ static void vc4_atomic_commit_tail(struct drm_atomic_state *state)
drm_dbg(dev, "Running the core clock at %lu Hz\n",
new_hvs_state->core_clock_rate);

+ /*
+ * Request a clock rate based on the current HVS
+ * requirements.
+ */
clk_set_min_rate(hvs->core_clk, new_hvs_state->core_clock_rate);
}
}
--
2.35.1