On Mon, 17 Aug 2015, libin.yang@intel.com wrote:
From: Libin Yang libin.yang@intel.com
HDMI audio may not work at some frequencies with the HW provided N/CTS.
This patch sets the proper N value for the given audio sample rate at the impacted frequencies. At other frequencies, it will use the N/CTS value which HW provides.
Signed-off-by: Libin Yang libin.yang@intel.com
drivers/gpu/drm/i915/intel_audio.c | 117 +++++++++++++++++++++++++++++++++++++ 1 file changed, 117 insertions(+)
diff --git a/drivers/gpu/drm/i915/intel_audio.c b/drivers/gpu/drm/i915/intel_audio.c index dc32cf4..27add6a 100644 --- a/drivers/gpu/drm/i915/intel_audio.c +++ b/drivers/gpu/drm/i915/intel_audio.c @@ -68,6 +68,31 @@ static const struct { { 148500, AUD_CONFIG_PIXEL_CLOCK_HDMI_148500 }, };
+/* HDMI N/CTS table */ +#define TMDS_297M 297000 +#define TMDS_296M DIV_ROUND_UP(297000 * 1000, 1001) +static const struct {
- int sample_rate;
- int clock;
- int n;
- int cts;
+} aud_ncts[] = {
- { 44100, TMDS_296M, 4459, 234375 },
- { 44100, TMDS_297M, 4704, 247500 },
- { 48000, TMDS_296M, 5824, 281250 },
- { 48000, TMDS_297M, 5120, 247500 },
- { 32000, TMDS_296M, 5824, 421875 },
- { 32000, TMDS_297M, 3072, 222750 },
- { 88200, TMDS_296M, 8918, 234375 },
- { 88200, TMDS_297M, 9408, 247500 },
- { 96000, TMDS_296M, 11648, 281250 },
- { 96000, TMDS_297M, 10240, 247500 },
- { 176400, TMDS_296M, 17836, 234375 },
- { 176400, TMDS_297M, 18816, 247500 },
- { 44100, TMDS_296M, 23296, 281250 },
- { 44100, TMDS_297M, 20480, 247500 },
+};
/* get AUD_CONFIG_PIXEL_CLOCK_HDMI_* value for mode */ static u32 audio_config_hdmi_pixel_clock(struct drm_display_mode *mode) { @@ -90,6 +115,31 @@ static u32 audio_config_hdmi_pixel_clock(struct drm_display_mode *mode) return hdmi_audio_clock[i].config; }
+static int audio_config_get_n(struct drm_display_mode *mode, int rate) +{
- int i;
- for (i = 0; i < ARRAY_SIZE(aud_ncts); i++) {
if ((rate == aud_ncts[i].sample_rate) &&
(mode->clock == aud_ncts[i].clock)) {
return aud_ncts[i].n;
}
- }
- return 0;
+}
+/* check whether N/CTS/M need be set manually */ +static bool audio_rate_need_prog(struct intel_crtc *crtc,
struct drm_display_mode *mode)
+{
- if (((mode->clock == TMDS_297M) ||
(mode->clock == TMDS_296M)) &&
intel_pipe_has_type(crtc, INTEL_OUTPUT_HDMI))
return true;
- else
return false;
+}
static bool intel_eld_uptodate(struct drm_connector *connector, int reg_eldv, uint32_t bits_eldv, int reg_elda, uint32_t bits_elda, @@ -514,12 +564,79 @@ static int i915_audio_component_get_cdclk_freq(struct device *dev) return ret; }
+static int i915_audio_component_sync_audio_rate(struct device *dev,
int port, int rate)
+{
- struct drm_i915_private *dev_priv = dev_to_i915(dev);
- struct drm_device *drm_dev = dev_priv->dev;
- struct intel_encoder *intel_encoder;
- struct intel_digital_port *intel_dig_port;
- struct intel_crtc *crtc;
- struct drm_display_mode *mode;
- enum pipe pipe = -1;
- u32 tmp;
- int n_low, n_up, n;
- /* 1. get the pipe */
- for_each_intel_encoder(drm_dev, intel_encoder) {
intel_dig_port = enc_to_dig_port(&intel_encoder->base);
Mmmh, not all encoders are digital ports. enc_to_dig_port does a container_of, so you can't just check for NULL either. IOW, you need to check the encoder->type (and you only care about HDMI here).
if (port == intel_dig_port->port) {
crtc = to_intel_crtc(intel_encoder->base.crtc);
if (!crtc) {
DRM_DEBUG_KMS("%s: crtc is NULL\n", __func__);
continue;
}
pipe = crtc->pipe;
break;
}
- }
- if (pipe == INVALID_PIPE) {
DRM_DEBUG_KMS("no pipe for the port %c\n", port_name(port));
return -ENODEV;
- }
- DRM_DEBUG_KMS("pipe %c connects port %c\n",
pipe_name(pipe), port_name(port));
- mode = &crtc->config->base.adjusted_mode;
- /* 2. check whether to set the N/CTS/M manually or not */
- if (!audio_rate_need_prog(crtc, mode)) {
tmp = I915_READ(HSW_AUD_CFG(pipe));
tmp &= ~AUD_CONFIG_N_PROG_ENABLE;
I915_WRITE(HSW_AUD_CFG(pipe), tmp);
return 0;
- }
- n = audio_config_get_n(mode, rate);
- if (n == 0) {
DRM_DEBUG_KMS("Using automatic mode for N value on port %c\n",
port_name(port));
tmp = I915_READ(HSW_AUD_CFG(pipe));
tmp &= ~AUD_CONFIG_N_PROG_ENABLE;
I915_WRITE(HSW_AUD_CFG(pipe), tmp);
return 0;
- }
- n_low = n & 0xfff;
- n_up = (n >> 12) & 0xff;
- /* 4. set the N/CTS/M */
- tmp = I915_READ(HSW_AUD_CFG(pipe));
- tmp &= ~(AUD_CONFIG_UPPER_N_MASK | AUD_CONFIG_LOWER_N_MASK);
- tmp |= ((n_up << AUD_CONFIG_UPPER_N_SHIFT) |
(n_low << AUD_CONFIG_LOWER_N_SHIFT) |
AUD_CONFIG_N_PROG_ENABLE);
- I915_WRITE(HSW_AUD_CFG(pipe), tmp);
- return 0;
+}
static const struct i915_audio_component_ops i915_audio_component_ops = { .owner = THIS_MODULE, .get_power = i915_audio_component_get_power, .put_power = i915_audio_component_put_power, .codec_wake_override = i915_audio_component_codec_wake_override, .get_cdclk_freq = i915_audio_component_get_cdclk_freq,
- .sync_audio_rate = i915_audio_component_sync_audio_rate,
};
static int i915_audio_component_bind(struct device *i915_dev,
1.9.1