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

[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>
---
 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 {
-- 
1.8.3.1