On Wed, 12 Oct 2022, Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> wrote:
> On Tue, 11 Oct 2022, Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx> wrote:
>> From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
>>
>> We currently read the ELD buffer size from hardware on g4x,
>> but on ilk+ we just hardcode it to 84 bytes. Let's unify
>> this and just do the hardware readout on all platforms,
>> in case the size changes in the future or something.
>>
>> TODO: should perhaps do the readout during driver init and
>> stash the results somewhere so that we could check that the
>> connector's ELD actually fits and not even try to enable audio
>> in that case...
>>
>> Cc: Chaitanya Kumar Borah <chaitanya.kumar.borah@xxxxxxxxx>
>> Cc: Kai Vehmanen <kai.vehmanen@xxxxxxxxxxxxxxx>
>> Cc: Takashi Iwai <tiwai@xxxxxxx>
>> Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
>
> Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx>
Might add comments above the *_eld_buffer_size() functions to indicate
they return the buffer size in dwords, not bytes which would be the
obvious thing.
>
>> ---
>> drivers/gpu/drm/i915/display/intel_audio.c | 49 ++++++++++++++++++----
>> 1 file changed, 42 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_audio.c b/drivers/gpu/drm/i915/display/intel_audio.c
>> index 3f328913fc90..abca5f23673a 100644
>> --- a/drivers/gpu/drm/i915/display/intel_audio.c
>> +++ b/drivers/gpu/drm/i915/display/intel_audio.c
>> @@ -304,6 +304,15 @@ static int audio_config_hdmi_get_n(const struct intel_crtc_state *crtc_state,
>> return 0;
>> }
>>
>> +static int g4x_eld_buffer_size(struct drm_i915_private *i915)
>> +{
>> + u32 tmp;
>> +
>> + tmp = intel_de_read(i915, G4X_AUD_CNTL_ST);
>> +
>> + return REG_FIELD_GET(G4X_ELD_BUFFER_SIZE_MASK, tmp);
>> +}
>> +
>> static void g4x_audio_codec_disable(struct intel_encoder *encoder,
>> const struct intel_crtc_state *old_crtc_state,
>> const struct drm_connector_state *old_conn_state)
>> @@ -329,10 +338,11 @@ static void g4x_audio_codec_enable(struct intel_encoder *encoder,
>>
>> tmp = intel_de_read(i915, G4X_AUD_CNTL_ST);
>> tmp &= ~(G4X_ELD_VALID | G4X_ELD_ADDRESS_MASK);
>> - len = REG_FIELD_GET(G4X_ELD_BUFFER_SIZE_MASK, tmp);
>> intel_de_write(i915, G4X_AUD_CNTL_ST, tmp);
>>
>> + len = g4x_eld_buffer_size(i915);
>> len = min(drm_eld_size(eld) / 4, len);
>> +
>> for (i = 0; i < len; i++)
>> intel_de_write(i915, G4X_HDMIW_HDMIEDID,
>> *((const u32 *)eld + i));
>> @@ -442,6 +452,16 @@ hsw_audio_config_update(struct intel_encoder *encoder,
>> hsw_hdmi_audio_config_update(encoder, crtc_state);
>> }
>>
>> +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)
>> @@ -615,9 +635,10 @@ static void hsw_audio_codec_enable(struct intel_encoder *encoder,
>> tmp &= ~IBX_ELD_ADDRESS_MASK;
>> intel_de_write(i915, HSW_AUD_DIP_ELD_CTRL(cpu_transcoder), tmp);
>>
>> - /* Up to 84 bytes of hw ELD buffer */
>> - len = min(drm_eld_size(eld), 84);
>> - for (i = 0; i < len / 4; i++)
>> + len = hsw_eld_buffer_size(i915, cpu_transcoder);
>> + len = min(drm_eld_size(eld) / 4, len);
>> +
>> + for (i = 0; i < len; i++)
>> intel_de_write(i915, HSW_AUD_EDID_DATA(cpu_transcoder),
>> *((const u32 *)eld + i));
>>
>> @@ -658,6 +679,19 @@ static void ilk_audio_regs_init(struct drm_i915_private *i915,
>> }
>> }
>>
>> +static int ilk_eld_buffer_size(struct drm_i915_private *i915,
>> + enum pipe pipe)
>> +{
>> + struct ilk_audio_regs regs;
>> + u32 tmp;
>> +
>> + ilk_audio_regs_init(i915, pipe, ®s);
>> +
>> + tmp = intel_de_read(i915, regs.aud_cntl_st);
>> +
>> + return REG_FIELD_GET(IBX_ELD_BUFFER_SIZE_MASK, tmp);
>> +}
>> +
>> static void ilk_audio_codec_disable(struct intel_encoder *encoder,
>> const struct intel_crtc_state *old_crtc_state,
>> const struct drm_connector_state *old_conn_state)
>> @@ -732,9 +766,10 @@ static void ilk_audio_codec_enable(struct intel_encoder *encoder,
>> tmp &= ~IBX_ELD_ADDRESS_MASK;
>> intel_de_write(i915, regs.aud_cntl_st, tmp);
>>
>> - /* Up to 84 bytes of hw ELD buffer */
>> - len = min(drm_eld_size(eld), 84);
>> - for (i = 0; i < len / 4; i++)
>> + len = ilk_eld_buffer_size(i915, pipe);
>> + len = min(drm_eld_size(eld) / 4, len);
>> +
>> + for (i = 0; i < len; i++)
>> intel_de_write(i915, regs.hdmiw_hdmiedid,
>> *((const u32 *)eld + i));
--
Jani Nikula, Intel Open Source Graphics Center
