[alsa-devel] [PATCH] drm/i915: set proper N/CTS in modeset
libin.yang at intel.com
libin.yang at intel.com
Thu Sep 10 09:29:45 CEST 2015
From: Libin Yang <libin.yang at intel.com>
When modeset occurs and the TMDS frequency is set to some
speical values, the N/CTS need to be set manually if audio
is playing.
Signed-off-by: Libin Yang <libin.yang at intel.com>
---
drivers/gpu/drm/i915/intel_audio.c | 56 ++++++++++++++++++++++++++++++++------
include/drm/i915_component.h | 11 ++++++++
2 files changed, 58 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_audio.c b/drivers/gpu/drm/i915/intel_audio.c
index e3c32ce..a12bf57 100644
--- a/drivers/gpu/drm/i915/intel_audio.c
+++ b/drivers/gpu/drm/i915/intel_audio.c
@@ -128,6 +128,20 @@ static int audio_config_get_n(const struct drm_display_mode *mode, int rate)
return 0;
}
+static uint32_t audio_config_setup_n_reg(int n, uint32_t val)
+{
+ int n_low, n_up;
+ uint32_t tmp = val;
+
+ n_low = n & 0xfff;
+ n_up = (n >> 12) & 0xff;
+ 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);
+ return tmp;
+}
+
/* check whether N/CTS/M need be set manually */
static bool audio_rate_need_prog(struct intel_crtc *crtc,
struct drm_display_mode *mode)
@@ -262,9 +276,14 @@ static void hsw_audio_codec_enable(struct drm_connector *connector,
struct drm_i915_private *dev_priv = connector->dev->dev_private;
struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
enum pipe pipe = intel_crtc->pipe;
+ struct i915_audio_component *acomp = dev_priv->audio_component;
const uint8_t *eld = connector->eld;
+ struct intel_digital_port *intel_dig_port =
+ enc_to_dig_port(&encoder->base);
+ enum port port = intel_dig_port->port;
uint32_t tmp;
int len, i;
+ int n, rate;
DRM_DEBUG_KMS("Enable audio codec on pipe %c, %u bytes ELD\n",
pipe_name(pipe), drm_eld_size(eld));
@@ -302,12 +321,29 @@ static void hsw_audio_codec_enable(struct drm_connector *connector,
/* Enable timestamps */
tmp = I915_READ(HSW_AUD_CFG(pipe));
tmp &= ~AUD_CONFIG_N_VALUE_INDEX;
- tmp &= ~AUD_CONFIG_N_PROG_ENABLE;
tmp &= ~AUD_CONFIG_PIXEL_CLOCK_HDMI_MASK;
if (intel_pipe_has_type(intel_crtc, INTEL_OUTPUT_DISPLAYPORT))
tmp |= AUD_CONFIG_N_VALUE_INDEX;
else
tmp |= audio_config_hdmi_pixel_clock(mode);
+
+ tmp &= ~AUD_CONFIG_N_PROG_ENABLE;
+ if (audio_rate_need_prog(intel_crtc, mode)) {
+ if (!acomp)
+ rate = 0;
+ else if (port >= PORT_A && port <= PORT_E)
+ rate = acomp->aud_sample_rate[port];
+ else {
+ DRM_ERROR("invalid port: %d\n", port);
+ rate = 0;
+ }
+ n = audio_config_get_n(mode, rate);
+ if (n != 0)
+ tmp = audio_config_setup_n_reg(n, tmp);
+ else
+ DRM_DEBUG_KMS("no suitable N value is found\n");
+ }
+
I915_WRITE(HSW_AUD_CFG(pipe), tmp);
mutex_unlock(&dev_priv->av_mutex);
@@ -594,9 +630,10 @@ static int i915_audio_component_sync_audio_rate(struct device *dev,
struct intel_digital_port *intel_dig_port;
struct intel_crtc *crtc;
struct drm_display_mode *mode;
+ struct i915_audio_component *acomp = dev_priv->audio_component;
enum pipe pipe = -1;
u32 tmp;
- int n_low, n_up, n;
+ int n;
/* HSW, BDW SKL need this fix */
if (!IS_SKYLAKE(dev_priv) &&
@@ -630,6 +667,9 @@ static int i915_audio_component_sync_audio_rate(struct device *dev,
pipe_name(pipe), port_name(port));
mode = &crtc->config->base.adjusted_mode;
+ /* port must be valid now, otherwise the pipe will be invalid */
+ acomp->aud_sample_rate[port] = rate;
+
/* 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));
@@ -649,15 +689,10 @@ static int i915_audio_component_sync_audio_rate(struct device *dev,
mutex_unlock(&dev_priv->av_mutex);
return 0;
}
- n_low = n & 0xfff;
- n_up = (n >> 12) & 0xff;
- /* 4. set the N/CTS/M */
+ /* 3. 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);
+ tmp = audio_config_setup_n_reg(n, tmp);
I915_WRITE(HSW_AUD_CFG(pipe), tmp);
mutex_unlock(&dev_priv->av_mutex);
@@ -678,6 +713,7 @@ static int i915_audio_component_bind(struct device *i915_dev,
{
struct i915_audio_component *acomp = data;
struct drm_i915_private *dev_priv = dev_to_i915(i915_dev);
+ int i;
if (WARN_ON(acomp->ops || acomp->dev))
return -EEXIST;
@@ -685,6 +721,8 @@ static int i915_audio_component_bind(struct device *i915_dev,
drm_modeset_lock_all(dev_priv->dev);
acomp->ops = &i915_audio_component_ops;
acomp->dev = i915_dev;
+ for (i = 0; i < I915_MAX_PORTS; i++)
+ acomp->aud_sample_rate[i] = 0;
dev_priv->audio_component = acomp;
drm_modeset_unlock_all(dev_priv->dev);
diff --git a/include/drm/i915_component.h b/include/drm/i915_component.h
index e6d35d7..11999eb 100644
--- a/include/drm/i915_component.h
+++ b/include/drm/i915_component.h
@@ -24,8 +24,19 @@
#ifndef _I915_COMPONENT_H_
#define _I915_COMPONENT_H_
+/* MAX_PORT is the number of port
+ * It must be sync with I915_MAX_PORTS defined i915_drv.h
+ * 5 should be enough as only HSW, BDW, SKL need such fix.
+ * The 4K resolution audio issue should be fixed on CNL
+ */
+#define MAX_PORTS 5
+
struct i915_audio_component {
struct device *dev;
+ /**
+ * @aud_sample_rate: the array of audio sample rate per port
+ */
+ int aud_sample_rate[MAX_PORTS];
const struct i915_audio_component_ops {
struct module *owner;
--
1.9.1
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