From: Dom Cobley Date: Tue, 25 May 2021 13:23:51 +0000 (+0200) Subject: drm/vc4: hdmi: Remove firmware logic for MAI threshold setting X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=8434111ccfec8fc0549ec325a632067232d38e14;p=linux.git drm/vc4: hdmi: Remove firmware logic for MAI threshold setting This was a workaround for bugs in hardware on earlier Pi models and wasn't totally successful. It makes audio quality worse on a Pi4 at the higher sample rates Signed-off-by: Dom Cobley Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20210525132354.297468-10-maxime@cerno.tech --- diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index e310a10bdba6b..054dec3100070 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -1380,22 +1380,12 @@ static int vc4_hdmi_audio_hw_params(struct snd_pcm_substream *substream, audio_packet_config |= VC4_SET_FIELD(channel_mask, VC4_HDMI_AUDIO_PACKET_CEA_MASK); - /* Set the MAI threshold. This logic mimics the firmware's. */ - if (vc4_hdmi->audio.samplerate > 96000) { - HDMI_WRITE(HDMI_MAI_THR, - VC4_SET_FIELD(0x12, VC4_HD_MAI_THR_DREQHIGH) | - VC4_SET_FIELD(0x12, VC4_HD_MAI_THR_DREQLOW)); - } else if (vc4_hdmi->audio.samplerate > 48000) { - HDMI_WRITE(HDMI_MAI_THR, - VC4_SET_FIELD(0x14, VC4_HD_MAI_THR_DREQHIGH) | - VC4_SET_FIELD(0x12, VC4_HD_MAI_THR_DREQLOW)); - } else { - HDMI_WRITE(HDMI_MAI_THR, - VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_PANICHIGH) | - VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_PANICLOW) | - VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_DREQHIGH) | - VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_DREQLOW)); - } + /* Set the MAI threshold */ + HDMI_WRITE(HDMI_MAI_THR, + VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_PANICHIGH) | + VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_PANICLOW) | + VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_DREQHIGH) | + VC4_SET_FIELD(0x10, VC4_HD_MAI_THR_DREQLOW)); HDMI_WRITE(HDMI_MAI_CONFIG, VC4_HDMI_MAI_CONFIG_BIT_REVERSE |