From: Ville Syrjälä Date: Tue, 24 Jan 2023 14:46:17 +0000 (+0200) Subject: drm/i915/audio: Don't program the hardware ELD buffer on hsw+ X-Git-Tag: v6.6.7~1918^2~17^2~661 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=68470541e630bb43f047cd372cc49489c0e82084;p=platform%2Fkernel%2Flinux-starfive.git drm/i915/audio: Don't program the hardware ELD buffer on hsw+ Since we use the audio component to transfer the ELD to the audio driver on hsw+ platforms there is no point in even programming the hardware ELD buffer. Stop doing so. The one slight caveat here is that this is not strictly legal according to the HDA spec. PD=1;ELD=0 is only documented as an intermediate state during modeset. But if there is no hardware that depends on that then I guess we're fine. Or we could perhaps set ELD=1 without actually programming the buffer? Note that the bspec sequence of PD=0;ELD=0 -> PD=1;ELD=0 -> PD=1;ELD=1 is also not strictly correct according to the HDA spec, as the only documented transition from PD=0;ELD=0 is straight to PD=1;ELD=1. Additionally on hsw/bdw the hardware buffer is tied in with the dedicated display HDA controller's power state, so currently we mostly fail at proramming the buffer anyway. When the HDA side is not sufficiently powered up the ELD address bits get stuck and the ELD data register accesses go nowhere. Cc: Chaitanya Kumar Borah Cc: Takashi Iwai References: https://lore.kernel.org/intel-gfx/20221012104936.30911-1-ville.syrjala@linux.intel.com/ Reviewed-by: Kai Vehmanen Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20230124144628.4649-3-ville.syrjala@linux.intel.com --- diff --git a/drivers/gpu/drm/i915/display/intel_audio.c b/drivers/gpu/drm/i915/display/intel_audio.c index fb8a960..afebae9 100644 --- a/drivers/gpu/drm/i915/display/intel_audio.c +++ b/drivers/gpu/drm/i915/display/intel_audio.c @@ -459,17 +459,6 @@ hsw_audio_config_update(struct intel_encoder *encoder, hsw_hdmi_audio_config_update(encoder, crtc_state); } -/* ELD buffer size in dwords */ -static int hsw_eld_buffer_size(struct drm_i915_private *i915, - enum transcoder cpu_transcoder) -{ - u32 tmp; - - tmp = intel_de_read(i915, HSW_AUD_DIP_ELD_CTRL(cpu_transcoder)); - - return REG_FIELD_GET(IBX_ELD_BUFFER_SIZE_MASK, tmp); -} - static void hsw_audio_codec_disable(struct intel_encoder *encoder, const struct intel_crtc_state *old_crtc_state, const struct drm_connector_state *old_conn_state) @@ -618,10 +607,7 @@ static void hsw_audio_codec_enable(struct intel_encoder *encoder, { struct drm_i915_private *i915 = to_i915(encoder->base.dev); struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc); - struct drm_connector *connector = conn_state->connector; enum transcoder cpu_transcoder = crtc_state->cpu_transcoder; - const u32 *eld = (const u32 *)connector->eld; - int eld_buffer_size, len, i; mutex_lock(&i915->display.audio.mutex); @@ -639,25 +625,10 @@ static void hsw_audio_codec_enable(struct intel_encoder *encoder, intel_de_rmw(i915, HSW_AUD_PIN_ELD_CP_VLD, AUDIO_ELD_VALID(cpu_transcoder), 0); - /* Reset ELD address */ - intel_de_rmw(i915, HSW_AUD_DIP_ELD_CTRL(cpu_transcoder), - IBX_ELD_ADDRESS_MASK, 0); - - eld_buffer_size = hsw_eld_buffer_size(i915, cpu_transcoder); - len = min(drm_eld_size(connector->eld) / 4, eld_buffer_size); - - for (i = 0; i < len; i++) - intel_de_write(i915, HSW_AUD_EDID_DATA(cpu_transcoder), eld[i]); - for (; i < eld_buffer_size; i++) - intel_de_write(i915, HSW_AUD_EDID_DATA(cpu_transcoder), 0); - - drm_WARN_ON(&i915->drm, - (intel_de_read(i915, HSW_AUD_DIP_ELD_CTRL(cpu_transcoder)) & - IBX_ELD_ADDRESS_MASK) != 0); - - /* ELD valid */ - intel_de_rmw(i915, HSW_AUD_PIN_ELD_CP_VLD, - 0, AUDIO_ELD_VALID(cpu_transcoder)); + /* + * The audio componenent is used to convey the ELD + * instead using of the hardware ELD buffer. + */ /* Enable timestamps */ hsw_audio_config_update(encoder, crtc_state);