Hi Daniel,
-----Original Message----- From: Daniel Vetter [mailto:daniel.vetter@ffwll.ch] On Behalf Of Daniel Vetter Sent: Wednesday, August 26, 2015 3:53 PM To: Jani Nikula Cc: Yang, Libin; alsa-devel@alsa-project.org; tiwai@suse.de; intel- gfx@lists.freedesktop.org; daniel.vetter@ffwll.ch Subject: Re: [Intel-gfx] [PATCH v3 2/4] drm/i915: implement sync_audio_rate callback
On Mon, Aug 17, 2015 at 03:20:38PM +0300, Jani Nikula wrote:
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).
encoder->type is changed at runtime thanks to ddi encoders. Also shouldn't we care about dp audio too or am I confused?
Do you have suggestion how to handle it as it is changed at runtime? Need a lock or not?
For DP, because the 4K DP display is not stable, so we didn't do the full test on DP and no patch is ready for DP currently.
Based on the very simple test on DP, it seems DP audio is OK. When DP is stable, we will do the full test and decide to make the patch or not based on the test result.
Regards, Libin
-Daniel
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
-- Jani Nikula, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
-- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch