drm/radeon: fix DP audio support for APU with DCE4.1 display engine

BugLink: http://bugs.launchpad.net/bugs/1553179

commit fe6fc1f1 upstream.

Properly setup the DFS divider for DP audio for DCE4.1.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

drivers/gpu/drm/radeon/evergreen_hdmi.c

@@ -289,6 +289,16 @@ void dce4_dp_audio_set_dto(struct radeon_device *rdev,
 	 * number (coefficient of two integer numbers.  DCCG_AUDIO_DTOx_PHASE
 	 * is the numerator, DCCG_AUDIO_DTOx_MODULE is the denominator
 	 */
+	if (ASIC_IS_DCE41(rdev)) {
+		unsigned int div = (RREG32(DCE41_DENTIST_DISPCLK_CNTL) &
+			DENTIST_DPREFCLK_WDIVIDER_MASK) >>
+			DENTIST_DPREFCLK_WDIVIDER_SHIFT;
+		div = radeon_audio_decode_dfs_div(div);
+
+		if (div)
+			clock = 100 * clock / div;
+	}
+
 	WREG32(DCCG_AUDIO_DTO1_PHASE, 24000);
 	WREG32(DCCG_AUDIO_DTO1_MODULE, clock);
 }

drivers/gpu/drm/radeon/evergreend.h

@@ -511,6 +511,11 @@
 #define DCCG_AUDIO_DTO1_CNTL              0x05cc
 #       define DCCG_AUDIO_DTO1_USE_512FBR_DTO (1 << 3)
 
+#define DCE41_DENTIST_DISPCLK_CNTL			0x049c
+#       define DENTIST_DPREFCLK_WDIVIDER(x)		(((x) & 0x7f) << 24)
+#       define DENTIST_DPREFCLK_WDIVIDER_MASK		(0x7f << 24)
+#       define DENTIST_DPREFCLK_WDIVIDER_SHIFT		24
+
 /* DCE 4.0 AFMT */
 #define HDMI_CONTROL                         0x7030
 #       define HDMI_KEEPOUT_MODE             (1 << 0)

drivers/gpu/drm/radeon/radeon_atombios.c

@@ -1106,6 +1106,31 @@ union firmware_info {
 	ATOM_FIRMWARE_INFO_V2_2 info_22;
 };
 
+union igp_info {
+	struct _ATOM_INTEGRATED_SYSTEM_INFO info;
+	struct _ATOM_INTEGRATED_SYSTEM_INFO_V2 info_2;
+	struct _ATOM_INTEGRATED_SYSTEM_INFO_V6 info_6;
+	struct _ATOM_INTEGRATED_SYSTEM_INFO_V1_7 info_7;
+	struct _ATOM_INTEGRATED_SYSTEM_INFO_V1_8 info_8;
+};
+
+static void radeon_atombios_get_dentist_vco_freq(struct radeon_device *rdev)
+{
+	struct radeon_mode_info *mode_info = &rdev->mode_info;
+	int index = GetIndexIntoMasterTable(DATA, IntegratedSystemInfo);
+	union igp_info *igp_info;
+	u8 frev, crev;
+	u16 data_offset;
+
+	if (atom_parse_data_header(mode_info->atom_context, index, NULL,
+			&frev, &crev, &data_offset)) {
+		igp_info = (union igp_info *)(mode_info->atom_context->bios +
+			data_offset);
+		rdev->clock.vco_freq =
+			le32_to_cpu(igp_info->info_6.ulDentistVCOFreq);
+	}
+}
+
 bool radeon_atom_get_clock_info(struct drm_device *dev)
 {
 	struct radeon_device *rdev = dev->dev_private;
@@ -1260,6 +1285,10 @@ bool radeon_atom_get_clock_info(struct drm_device *dev)
 		if (ASIC_IS_DCE8(rdev))
 			rdev->clock.vco_freq =
 				le32_to_cpu(firmware_info->info_22.ulGPUPLL_OutputFreq);
+		else if (ASIC_IS_DCE5(rdev))
+			rdev->clock.vco_freq = rdev->clock.current_dispclk;
+		else if (ASIC_IS_DCE41(rdev))
+			radeon_atombios_get_dentist_vco_freq(rdev);
 		else
 			rdev->clock.vco_freq = rdev->clock.current_dispclk;
 
@@ -1272,14 +1301,6 @@ bool radeon_atom_get_clock_info(struct drm_device *dev)
 	return false;
 }
 
-union igp_info {
-	struct _ATOM_INTEGRATED_SYSTEM_INFO info;
-	struct _ATOM_INTEGRATED_SYSTEM_INFO_V2 info_2;
-	struct _ATOM_INTEGRATED_SYSTEM_INFO_V6 info_6;
-	struct _ATOM_INTEGRATED_SYSTEM_INFO_V1_7 info_7;
-	struct _ATOM_INTEGRATED_SYSTEM_INFO_V1_8 info_8;
-};
-
 bool radeon_atombios_sideport_present(struct radeon_device *rdev)
 {
 	struct radeon_mode_info *mode_info = &rdev->mode_info;