From 457e5184b9e0e14b26044c7fed5940bcbe7698a7 Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Mon, 28 Mar 2022 17:36:58 +0200 Subject: [PATCH] drm/vc4: kms: Warn if we have an incompatible muxing setup The documentation explicitly states we must prevent the output 2 and 3 from feeding from the same HVS channel. Let's add a warning to make some noise if we ever find ourselves in such a case. Signed-off-by: Maxime Ripard Acked-by: Thomas Zimmermann Link: https://lore.kernel.org/r/20220328153659.2382206-6-maxime@cerno.tech --- drivers/gpu/drm/vc4/vc4_kms.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c index 0c6a519..ffd54aa 100644 --- a/drivers/gpu/drm/vc4/vc4_kms.c +++ b/drivers/gpu/drm/vc4/vc4_kms.c @@ -290,6 +290,10 @@ static void vc5_hvs_pv_muxing_commit(struct vc4_dev *vc4, switch (vc4_crtc->data->hvs_output) { case 2: + drm_WARN_ON(&vc4->base, + VC4_GET_FIELD(HVS_READ(SCALER_DISPCTRL), + SCALER_DISPCTRL_DSP3_MUX) == channel); + mux = (channel == 2) ? 0 : 1; reg = HVS_READ(SCALER_DISPECTRL); HVS_WRITE(SCALER_DISPECTRL, -- 2.7.4