On Mon, 17 Aug 2015, "Yang, Libin" libin.yang@intel.com wrote:
Hi Jani
-----Original Message----- From: Jani Nikula [mailto:jani.nikula@linux.intel.com] Sent: Monday, August 17, 2015 8:21 PM To: Yang, Libin; alsa-devel@alsa-project.org; tiwai@suse.de; intel- gfx@lists.freedesktop.org; daniel.vetter@ffwll.ch Cc: Yang, Libin Subject: Re: [PATCH v3 2/4] drm/i915: implement sync_audio_rate callback
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).
Do you mean it should be: if (!crtc || !intel_pipe_has_type(crtc, INTEL_OUTPUT_HDMI))
No, just check for intel_encoder->type as the first thing in the loop, and continue if it isn't HDMI.
if (intel_encoder->type != INTEL_OUTPUT_HDMI) continue;
regards, Libin
if (port == intel_dig_port->port) {crtc = to_intel_crtc(intel_encoder->base.crtc);if (!crtc) {DRM_DEBUG_KMS("%s: crtc isNULL\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 valueon 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
-- Jani Nikula, Intel Open Source Technology Center