From: Maxime Ripard maxime@cerno.tech
[ Upstream commit 1701a23a4ef0993964ccc2f2d5d13f83a5ff4c70 ]
The core clock computation takes into account both the load due to the input (ie, planes) and its output (ie, encoders).
However, while the input load needs to consider all the planes, and thus sum all of their associated loads, the output happens mostly in parallel.
Therefore, we need to consider only the maximum of all the output loads, and not the sum like we were doing. This resulted in a clock rate way too high which could be discarded for being too high by the clock framework.
Since recent changes, the clock framework will even downright reject it, leading to a core clock being too low for its current needs.
Fixes: 16e101051f32 ("drm/vc4: Increase the core clock based on HVS load") Signed-off-by: Maxime Ripard maxime@cerno.tech Reviewed-by: Dave Stevenson dave.stevenson@raspberrypi.com Link: https://lore.kernel.org/r/20220613144800.326124-4-maxime@cerno.tech Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/vc4/vc4_kms.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c index 992d6a240002..dba23ae2e65e 100644 --- a/drivers/gpu/drm/vc4/vc4_kms.c +++ b/drivers/gpu/drm/vc4/vc4_kms.c @@ -890,7 +890,9 @@ vc4_core_clock_atomic_check(struct drm_atomic_state *state) continue;
num_outputs++; - cob_rate += hvs_new_state->fifo_state[i].fifo_load; + cob_rate = max_t(unsigned long, + hvs_new_state->fifo_state[i].fifo_load, + cob_rate); }
pixel_rate = load_state->hvs_load;