drm/radeon: Add a common function for DFS handling

Move encoding of DFS (digital frequency synthesizer) divider into a
separate function and improve calculation precision.

Signed-off-by: Slava Grigorev <slava.grigorev@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/radeon/dce6_afmt.c b/drivers/gpu/drm/radeon/dce6_afmt.c
index ea4e3fc2744f101237830842c34b951f4a1efa7c..367a916f364e94617a1b15fcd7d78cd3f90c8dc6 100644 (file)
--- a/drivers/gpu/drm/radeon/dce6_afmt.c
+++ b/drivers/gpu/drm/radeon/dce6_afmt.c
@@ -304,18 +304,10 @@ void dce6_dp_audio_set_dto(struct radeon_device *rdev,
                unsigned int div = (RREG32(DENTIST_DISPCLK_CNTL) &
                        DENTIST_DPREFCLK_WDIVIDER_MASK) >>
                        DENTIST_DPREFCLK_WDIVIDER_SHIFT;
-
-               if (div < 128 && div >= 96)
-                       div -= 64;
-               else if (div >= 64)
-                       div = div / 2 - 16;
-               else if (div >= 8)
-                       div /= 4;
-               else
-                       div = 0;
+               div = radeon_audio_decode_dfs_div(div);
 
                if (div)
-                       clock /= div;
+                       clock = clock * 100 / div;
 
                WREG32(DCE8_DCCG_AUDIO_DTO1_PHASE, 24000);
                WREG32(DCE8_DCCG_AUDIO_DTO1_MODULE, clock);

diff --git a/drivers/gpu/drm/radeon/radeon_audio.c b/drivers/gpu/drm/radeon/radeon_audio.c
index 85e1c234f0203761f80d2d92e9af9c8c3f909b1b..b214663b370da00905faa882ea27513153aa91bd 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_audio.c
+++ b/drivers/gpu/drm/radeon/radeon_audio.c
@@ -775,3 +775,15 @@ void radeon_audio_dpms(struct drm_encoder *encoder, int mode)
        if (radeon_encoder->audio && radeon_encoder->audio->dpms)
                radeon_encoder->audio->dpms(encoder, mode == DRM_MODE_DPMS_ON);
 }
+
+unsigned int radeon_audio_decode_dfs_div(unsigned int div)
+{
+       if (div >= 8 && div < 64)
+               return (div - 8) * 25 + 200;
+       else if (div >= 64 && div < 96)
+               return (div - 64) * 50 + 1600;
+       else if (div >= 96 && div < 128)
+               return (div - 96) * 100 + 3200;
+       else
+               return 0;
+}

diff --git a/drivers/gpu/drm/radeon/radeon_audio.h b/drivers/gpu/drm/radeon/radeon_audio.h
index 059cc3012062a7b50708620c557771dcfea821c0..5c70cceaa4a6c35e673ff9c50306e36e7f93ff3d 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_audio.h
+++ b/drivers/gpu/drm/radeon/radeon_audio.h
@@ -79,5 +79,6 @@ void radeon_audio_fini(struct radeon_device *rdev);
 void radeon_audio_mode_set(struct drm_encoder *encoder,
        struct drm_display_mode *mode);
 void radeon_audio_dpms(struct drm_encoder *encoder, int mode);
+unsigned int radeon_audio_decode_dfs_div(unsigned int div);
 
 #endif