@@ -64,6 +64,9 @@
* struct &i915_audio_component_audio_ops @audio_ops is called from i915 driver.
*/
+#define AUDIO_SAMPLE_CONTAINER_SIZE 32
+#define MAX_CHANNEL_COUNT 8
+
struct intel_audio_funcs {
void (*audio_codec_enable)(struct intel_encoder *encoder,
const struct intel_crtc_state *crtc_state,
@@ -770,6 +773,39 @@ void intel_audio_sdp_split_update(struct intel_encoder *encoder,
crtc_state->sdp_split_enable ? AUD_ENABLE_SDP_SPLIT : 0);
}
+static int calc_audio_bw(int channel_count, int rate)
+{
+ int bandwidth = channel_count * rate * AUDIO_SAMPLE_CONTAINER_SIZE;
+ return bandwidth;
+}
+
+static void calc_audio_config_params(struct intel_crtc_state *pipe_config)
+{
+ struct drm_display_mode *adjusted_mode = &pipe_config->hw.adjusted_mode;
+ int channel_count;
+ int index, rate[] = { 192000, 176000, 96000, 88000, 48000, 44100, 32000 };
+ int audio_req_bandwidth, available_blank_bandwidth, vblank, hblank;
+
+ hblank = adjusted_mode->htotal - adjusted_mode->hdisplay;
+ vblank = adjusted_mode->vtotal - adjusted_mode->vdisplay;
+ available_blank_bandwidth = hblank * vblank *
+ drm_mode_vrefresh(adjusted_mode) * pipe_config->pipe_bpp;
+ for (channel_count = MAX_CHANNEL_COUNT; channel_count > 0; channel_count--) {
+ for (index = 0; index < ARRAY_SIZE(rate); index++) {
+ audio_req_bandwidth = calc_audio_bw(channel_count,
+ rate[index]);
+ if (audio_req_bandwidth < available_blank_bandwidth) {
+ pipe_config->audio.max_rate = rate[index];
+ pipe_config->audio.max_channel_count = channel_count;
+ return;
+ }
+ }
+ }
+
+ pipe_config->audio.max_rate = 0;
+ pipe_config->audio.max_channel_count = 0;
+}
+
bool intel_audio_compute_config(struct intel_encoder *encoder,
struct intel_crtc_state *crtc_state,
struct drm_connector_state *conn_state)
@@ -791,6 +827,8 @@ bool intel_audio_compute_config(struct intel_encoder *encoder,
crtc_state->eld[6] = drm_av_sync_delay(connector, adjusted_mode) / 2;
+ calc_audio_config_params(crtc_state);
+
return true;
}
@@ -1131,6 +1131,12 @@ struct intel_crtc_state {
struct {
bool has_audio;
+
+ /* Audio rate in Hz */
+ int max_rate;
+
+ /* Number of audio channels */
+ int max_channel_count;
} audio;
/*
Initialize the source audio capabilities in crtc_state property by setting them to their maximum supported values, including max_channel and max_frequency. This allows for the calculation of audio source capabilities with respect to the available mode bandwidth. These capabilities encompass parameters such as supported frequency and channel configurations. --v1: - Refactor max_channel and max_rate to this commit as it is being initialised here - Remove call for intel_audio_compute_eld to avoid any regression while merge. instead call it in different commit when it is defined. - Use int instead of unsigned int for max_channel and max_frequecy - Update commit message and header --v2: - Use signed instead of unsigned variables. - Avoid using magic numbers and give them proper name. --v3: - Move defines to intel_audio.c. - use consistent naming convention for rate and channel. - declare num_of_channel and aud_rate separately. - Declare index value outside of for loop. - Move Bandwidth calculation to intel_Audio.c as it is common for both DP and HDMI. Also use static. Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com> --- drivers/gpu/drm/i915/display/intel_audio.c | 38 +++++++++++++++++++ .../drm/i915/display/intel_display_types.h | 6 +++ 2 files changed, 44 insertions(+)