[PATCH v2 09/12] drm/vc4: hdmi: Remove firmware logic for MAI threshold setting
From: Maxime Ripard <hidden>
Date: 2021-05-25 13:25:36
Also in:
alsa-devel, dri-devel, linux-arm-kernel, linux-doc, lkml
Subsystem:
drm drivers, drm drivers and misc gpu patches, drm drivers for vc4, the rest · Maintainers:
David Airlie, Simona Vetter, Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Dave Stevenson, Linus Torvalds
From: Dom Cobley <redacted> 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 <redacted> Signed-off-by: Maxime Ripard <redacted> --- drivers/gpu/drm/vc4/vc4_hdmi.c | 22 ++++++---------------- 1 file changed, 6 insertions(+), 16 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 0cf9949a749f..b7e3bd89e237 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c@@ -1269,22 +1269,12 @@ 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 |
--
2.31.1