drm/i915: set proper N/CTS in modeset

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@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/drivers/gpu/drm/i915/intel_audio.c b/drivers/gpu/drm/i915/intel_audio.c
index c5922f902aafa0ea92262203cdc1b80726668a24..30f6859dcb3667e59724dbd65928dd5ffedd5851 100644 (file)
--- 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 +721,9 @@ 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;
+       BUILD_BUG_ON(MAX_PORTS != I915_MAX_PORTS);
+       for (i = 0; i < ARRAY_SIZE(acomp->aud_sample_rate); 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 e6d35d7239c0492aabf7b5d1b4334e89719128f7..89dc7d6bc1ccb94a8a65f06a45a1d35e18d8562c 100644 (file)
--- a/include/drm/i915_component.h
+++ b/include/drm/i915_component.h
@@ -24,8 +24,18 @@
 #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.
+ */
+#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;