[PATCH] drm/radeon/audio: use actual pll clock for setting up dto

[Christian König]

Am 19.10.2013 01:30, schrieb Alex Deucher:
> Use the actual pll clock (rather than the mode clock) to set
> up the audio dto.  This fixes audio playback speed issues
> when the pll clock does not exactly match the mode clock.
>
> Signed-off-by: Alex Deucher <alexander.deucher at amd.com>

Damn, had the same idea while sleeping over it. Patch is:

Reviewed-by: Christian König <christian.koenig at amd.com>

> ---
>   drivers/gpu/drm/radeon/atombios_crtc.c  |  2 ++
>   drivers/gpu/drm/radeon/evergreen_hdmi.c |  9 +++++----
>   drivers/gpu/drm/radeon/r600_hdmi.c      | 16 +++++++++-------
>   drivers/gpu/drm/radeon/radeon_mode.h    |  1 +
>   4 files changed, 17 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c
> index bf87f6d..3a6059f 100644
> --- a/drivers/gpu/drm/radeon/atombios_crtc.c
> +++ b/drivers/gpu/drm/radeon/atombios_crtc.c
> @@ -1027,6 +1027,8 @@ static void atombios_crtc_set_pll(struct drm_crtc *crtc, struct drm_display_mode
>   		radeon_compute_pll_legacy(pll, radeon_crtc->adjusted_clock, &pll_clock,
>   					  &fb_div, &frac_fb_div, &ref_div, &post_div);
>   
> +	radeon_crtc->pll_clock = pll_clock * 10; /* convert to khz units */
> +
>   	atombios_crtc_program_ss(rdev, ATOM_DISABLE, radeon_crtc->pll_id,
>   				 radeon_crtc->crtc_id, &radeon_crtc->ss);
>   
> diff --git a/drivers/gpu/drm/radeon/evergreen_hdmi.c b/drivers/gpu/drm/radeon/evergreen_hdmi.c
> index 6787365..0d55870 100644
> --- a/drivers/gpu/drm/radeon/evergreen_hdmi.c
> +++ b/drivers/gpu/drm/radeon/evergreen_hdmi.c
> @@ -225,7 +225,7 @@ static void evergreen_hdmi_update_avi_infoframe(struct drm_encoder *encoder,
>   		frame[0xC] | (frame[0xD] << 8) | (header[1] << 24));
>   }
>   
> -static void evergreen_audio_set_dto(struct drm_encoder *encoder, u32 clock)
> +static void evergreen_audio_set_dto(struct drm_encoder *encoder)
>   {
>   	struct drm_device *dev = encoder->dev;
>   	struct radeon_device *rdev = dev->dev_private;
> @@ -233,9 +233,10 @@ static void evergreen_audio_set_dto(struct drm_encoder *encoder, u32 clock)
>   	struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv;
>   	struct radeon_crtc *radeon_crtc = to_radeon_crtc(encoder->crtc);
>   	u32 base_rate = 24000;
> -	u32 max_ratio = clock / base_rate;
> +	u32 max_ratio = radeon_crtc->pll_clock / base_rate;
>   	u32 dto_phase;
> -	u32 dto_modulo = clock;
> +	/* need to use the exact pll clock here to keep audio rate correct */
> +	u32 dto_modulo = radeon_crtc->pll_clock;
>   	u32 wallclock_ratio;
>   	u32 dto_cntl;
>   
> @@ -296,7 +297,7 @@ void evergreen_hdmi_setmode(struct drm_encoder *encoder, struct drm_display_mode
>   		return;
>   	offset = dig->afmt->offset;
>   
> -	evergreen_audio_set_dto(encoder, mode->clock);
> +	evergreen_audio_set_dto(encoder);
>   
>   	WREG32(HDMI_VBI_PACKET_CONTROL + offset,
>   	       HDMI_NULL_SEND); /* send null packets when required */
> diff --git a/drivers/gpu/drm/radeon/r600_hdmi.c b/drivers/gpu/drm/radeon/r600_hdmi.c
> index 21f2b74..b8c444e 100644
> --- a/drivers/gpu/drm/radeon/r600_hdmi.c
> +++ b/drivers/gpu/drm/radeon/r600_hdmi.c
> @@ -219,16 +219,18 @@ static void r600_hdmi_audio_workaround(struct drm_encoder *encoder)
>   		 value, ~HDMI0_AUDIO_TEST_EN);
>   }
>   
> -void r600_audio_set_dto(struct drm_encoder *encoder, u32 clock)
> +static void r600_audio_set_dto(struct drm_encoder *encoder)
>   {
>   	struct drm_device *dev = encoder->dev;
>   	struct radeon_device *rdev = dev->dev_private;
>   	struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
>   	struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv;
> +	struct radeon_crtc *radeon_crtc = to_radeon_crtc(encoder->crtc);
>   	u32 base_rate = 24000;
> -	u32 max_ratio = clock / base_rate;
> +	u32 max_ratio = radeon_crtc->pll_clock / base_rate;
>   	u32 dto_phase;
> -	u32 dto_modulo = clock;
> +	/* need to use the exact pll clock here to keep audio rate correct */
> +	u32 dto_modulo = radeon_crtc->pll_clock;
>   	u32 wallclock_ratio;
>   	u32 dto_cntl;
>   
> @@ -279,17 +281,17 @@ void r600_audio_set_dto(struct drm_encoder *encoder, u32 clock)
>   		 */
>   		if (dig->dig_encoder == 0) {
>   			WREG32(DCCG_AUDIO_DTO0_PHASE, base_rate * 100);
> -			WREG32(DCCG_AUDIO_DTO0_MODULE, clock * 100);
> +			WREG32(DCCG_AUDIO_DTO0_MODULE, dto_modulo * 100);
>   			WREG32(DCCG_AUDIO_DTO_SELECT, 0); /* select DTO0 */
>   		} else {
>   			WREG32(DCCG_AUDIO_DTO1_PHASE, base_rate * 100);
> -			WREG32(DCCG_AUDIO_DTO1_MODULE, clock * 100);
> +			WREG32(DCCG_AUDIO_DTO1_MODULE, dto_modulo * 100);
>   			WREG32(DCCG_AUDIO_DTO_SELECT, 1); /* select DTO1 */
>   		}
>   	} else {
>   		/* according to the reg specs, this should be DCE2.0 and DCE3.0/3.1 */
>   		WREG32(AUDIO_DTO, AUDIO_DTO_PHASE(base_rate / 10) |
> -		       AUDIO_DTO_MODULE(clock / 10));
> +		       AUDIO_DTO_MODULE(dto_modulo / 10));
>   	}
>   }
>   
> @@ -420,7 +422,7 @@ void r600_hdmi_setmode(struct drm_encoder *encoder, struct drm_display_mode *mod
>   		return;
>   	offset = dig->afmt->offset;
>   
> -	r600_audio_set_dto(encoder, mode->clock);
> +	r600_audio_set_dto(encoder);
>   
>   	WREG32(HDMI0_VBI_PACKET_CONTROL + offset,
>   	       HDMI0_NULL_SEND); /* send null packets when required */
> diff --git a/drivers/gpu/drm/radeon/radeon_mode.h b/drivers/gpu/drm/radeon/radeon_mode.h
> index 8b4e712..5b5339b 100644
> --- a/drivers/gpu/drm/radeon/radeon_mode.h
> +++ b/drivers/gpu/drm/radeon/radeon_mode.h
> @@ -341,6 +341,7 @@ struct radeon_crtc {
>   	u32 wm_low;
>   	u32 wm_high;
>   	struct drm_display_mode hw_mode;
> +	u32 pll_clock; /* actual clock generated by the pll */
>   };
>   
>   struct radeon_encoder_primary_dac {