[Intel-gfx] [PATCH 5/5] drm/i915: Move hdcp msg detection into shim

Sean Paul seanpaul at chromium.org
Mon Feb 26 18:01:46 UTC 2018


On Mon, Feb 26, 2018 at 10:42:39PM +0530, Ramalingam C wrote:
> DP and HDMI HDCP specifications are varying with respect to
> detecting the R0 and ksv_fifo availability.
> 
> DP will produce CP_IRQ and set a bit for indicating the R0 and
> FIFO_READY status.

I'm not sure what the benefit is? Keeping things common was a deliberate
decision on my part to keep complexity down and increase the amount of common
code.

Sean

> 
> Whereas HDMI will set a bit for FIFO_READY but there is no bit
> indication for R0 ready. And also polling of READY bit is needed for
> HDMI as ther is no CP_IRQ.
> 
> So Fielding the CP_IRQ for DP and the polling the READY bit for a
> period and blindly waiting for a fixed time for R0 incase of HDMI are
> moved into corresponding hdcp_shim.
> 
> Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_dp.c   | 70 +++++++++++++++++++++++++++++++++++----
>  drivers/gpu/drm/i915/intel_drv.h  |  6 ++--
>  drivers/gpu/drm/i915/intel_hdcp.c | 39 ++--------------------
>  drivers/gpu/drm/i915/intel_hdmi.c | 28 +++++++++++++++-
>  4 files changed, 98 insertions(+), 45 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 2c3eb90b9499..afe310a91d3c 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -4436,6 +4436,7 @@ static bool
>  intel_dp_short_pulse(struct intel_dp *intel_dp)
>  {
>  	struct drm_i915_private *dev_priv = to_i915(intel_dp_to_dev(intel_dp));
> +	struct intel_connector *connector = intel_dp->attached_connector;
>  	u8 sink_irq_vector = 0;
>  	u8 old_sink_count = intel_dp->sink_count;
>  	bool ret;
> @@ -4470,8 +4471,11 @@ intel_dp_short_pulse(struct intel_dp *intel_dp)
>  
>  		if (sink_irq_vector & DP_AUTOMATED_TEST_REQUEST)
>  			intel_dp_handle_test_request(intel_dp);
> -		if (sink_irq_vector & (DP_CP_IRQ | DP_SINK_SPECIFIC_IRQ))
> -			DRM_DEBUG_DRIVER("CP or sink specific irq unhandled\n");
> +		if (sink_irq_vector & DP_CP_IRQ)
> +			if (connector->hdcp_shim)
> +				complete_all(&connector->cp_irq_recved);
> +		if (sink_irq_vector & DP_SINK_SPECIFIC_IRQ)
> +			DRM_DEBUG_DRIVER("Sink specific irq unhandled\n");
>  	}
>  
>  	intel_dp_check_link_status(intel_dp);
> @@ -5083,6 +5087,25 @@ void intel_dp_encoder_suspend(struct intel_encoder *intel_encoder)
>  	pps_unlock(intel_dp);
>  }
>  
> +static int intel_dp_hdcp_wait_for_cp_irq(struct completion *cp_irq_recved,
> +					 int timeout)
> +{
> +	long ret;
> +
> +	if (completion_done(cp_irq_recved))
> +		reinit_completion(cp_irq_recved);
> +
> +	ret = wait_for_completion_interruptible_timeout(cp_irq_recved,
> +							msecs_to_jiffies(
> +							timeout));
> +	reinit_completion(cp_irq_recved);
> +	if (ret < 0)
> +		return (int)ret;
> +	else if (!ret)
> +		return -ETIMEDOUT;
> +	return 0;
> +}
> +
>  static
>  int intel_dp_hdcp_write_an_aksv(struct intel_digital_port *intel_dig_port,
>  				u8 *an)
> @@ -5188,11 +5211,38 @@ int intel_dp_hdcp_repeater_present(struct intel_digital_port *intel_dig_port,
>  	return 0;
>  }
>  
> +static int intel_dp_hdcp_wait_for_r0(struct intel_digital_port *intel_dig_port)
> +{
> +	struct intel_dp *dp = &intel_dig_port->dp;
> +	struct intel_connector *connector = dp->attached_connector;
> +	int ret;
> +	u8 bstatus;
> +
> +	intel_dp_hdcp_wait_for_cp_irq(&connector->cp_irq_recved, 100);
> +
> +	ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_BSTATUS,
> +			       &bstatus, 1);
> +	if (ret != 1) {
> +		DRM_ERROR("Read bstatus from DP/AUX failed (%d)\n", ret);
> +		return ret >= 0 ? -EIO : ret;
> +	}
> +
> +	if (!(bstatus & DP_BSTATUS_R0_PRIME_READY))
> +		return -ETIMEDOUT;
> +
> +	return 0;
> +}
> +
>  static
>  int intel_dp_hdcp_read_ri_prime(struct intel_digital_port *intel_dig_port,
>  				u8 *ri_prime)
>  {
>  	ssize_t ret;
> +
> +	ret = intel_dp_hdcp_wait_for_r0(intel_dig_port);
> +	if (!ret)
> +		return ret;
> +
>  	ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_RI_PRIME,
>  			       ri_prime, DRM_HDCP_RI_LEN);
>  	if (ret != DRM_HDCP_RI_LEN) {
> @@ -5203,18 +5253,26 @@ int intel_dp_hdcp_read_ri_prime(struct intel_digital_port *intel_dig_port,
>  }
>  
>  static
> -int intel_dp_hdcp_read_ksv_ready(struct intel_digital_port *intel_dig_port,
> -				 bool *ksv_ready)
> +int intel_dp_hdcp_ksv_ready(struct intel_digital_port *intel_dig_port)
>  {
> +	struct intel_dp *dp = &intel_dig_port->dp;
> +	struct intel_connector *connector = dp->attached_connector;
>  	ssize_t ret;
>  	u8 bstatus;
> +
> +	intel_dp_hdcp_wait_for_cp_irq(&connector->cp_irq_recved,
> +				      5 * 1000 * 1000);
> +
>  	ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_BSTATUS,
>  			       &bstatus, 1);
>  	if (ret != 1) {
>  		DRM_ERROR("Read bstatus from DP/AUX failed (%zd)\n", ret);
>  		return ret >= 0 ? -EIO : ret;
>  	}
> -	*ksv_ready = bstatus & DP_BSTATUS_READY;
> +
> +	if (!(bstatus & DP_BSTATUS_READY))
> +		return -ETIMEDOUT;
> +
>  	return 0;
>  }
>  
> @@ -5305,7 +5363,7 @@ static const struct intel_hdcp_shim intel_dp_hdcp_shim = {
>  	.read_bstatus = intel_dp_hdcp_read_bstatus,
>  	.repeater_present = intel_dp_hdcp_repeater_present,
>  	.read_ri_prime = intel_dp_hdcp_read_ri_prime,
> -	.read_ksv_ready = intel_dp_hdcp_read_ksv_ready,
> +	.wait_for_ksv_ready = intel_dp_hdcp_ksv_ready,
>  	.read_ksv_fifo = intel_dp_hdcp_read_ksv_fifo,
>  	.read_v_prime_part = intel_dp_hdcp_read_v_prime_part,
>  	.toggle_signalling = intel_dp_hdcp_toggle_signalling,
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index 8f38e584d375..ab975107c978 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -353,8 +353,7 @@ struct intel_hdcp_shim {
>  	int (*read_ri_prime)(struct intel_digital_port *intel_dig_port, u8 *ri);
>  
>  	/* Determines if the receiver's KSV FIFO is ready for consumption */
> -	int (*read_ksv_ready)(struct intel_digital_port *intel_dig_port,
> -			      bool *ksv_ready);
> +	int (*wait_for_ksv_ready)(struct intel_digital_port *intel_dig_port);
>  
>  	/* Reads the ksv fifo for num_downstream devices */
>  	int (*read_ksv_fifo)(struct intel_digital_port *intel_dig_port,
> @@ -413,6 +412,9 @@ struct intel_connector {
>  	uint64_t hdcp_value; /* protected by hdcp_mutex */
>  	struct delayed_work hdcp_check_work;
>  	struct work_struct hdcp_prop_work;
> +
> +	/* To indicate the assertion of CP_IRQ */
> +	struct completion cp_irq_recved;
>  };
>  
>  struct intel_digital_connector_state {
> diff --git a/drivers/gpu/drm/i915/intel_hdcp.c b/drivers/gpu/drm/i915/intel_hdcp.c
> index 14be14a45e5a..a077e1333886 100644
> --- a/drivers/gpu/drm/i915/intel_hdcp.c
> +++ b/drivers/gpu/drm/i915/intel_hdcp.c
> @@ -57,27 +57,6 @@ static bool wait_for_hdcp_port(struct intel_connector *connector)
>  	return true;
>  }
>  
> -static int intel_hdcp_poll_ksv_fifo(struct intel_digital_port *intel_dig_port,
> -				    const struct intel_hdcp_shim *shim)
> -{
> -	int ret, read_ret;
> -	bool ksv_ready;
> -
> -	/* Poll for ksv list ready (spec says max time allowed is 5s) */
> -	ret = __wait_for(read_ret = shim->read_ksv_ready(intel_dig_port,
> -							 &ksv_ready),
> -			 read_ret || ksv_ready, 5 * 1000 * 1000, 1000,
> -			 100 * 1000);
> -	if (ret)
> -		return ret;
> -	if (read_ret)
> -		return read_ret;
> -	if (!ksv_ready)
> -		return -ETIMEDOUT;
> -
> -	return 0;
> -}
> -
>  static bool hdcp_key_loadable(struct drm_i915_private *dev_priv)
>  {
>  	struct i915_power_domains *power_domains = &dev_priv->power_domains;
> @@ -222,7 +201,7 @@ int intel_hdcp_auth_downstream(struct intel_digital_port *intel_dig_port,
>  
>  	dev_priv = intel_dig_port->base.base.dev->dev_private;
>  
> -	ret = intel_hdcp_poll_ksv_fifo(intel_dig_port, shim);
> +	ret = shim->wait_for_ksv_ready(intel_dig_port);
>  	if (ret) {
>  		DRM_ERROR("KSV list failed to become ready (%d)\n", ret);
>  		return ret;
> @@ -476,7 +455,6 @@ static int intel_hdcp_auth(struct intel_digital_port *intel_dig_port,
>  {
>  	struct drm_i915_private *dev_priv;
>  	enum port port;
> -	unsigned long r0_prime_gen_start;
>  	int ret, i, tries = 2;
>  	union {
>  		u32 reg[2];
> @@ -531,8 +509,6 @@ static int intel_hdcp_auth(struct intel_digital_port *intel_dig_port,
>  	if (ret)
>  		return ret;
>  
> -	r0_prime_gen_start = jiffies;
> -
>  	memset(&bksv, 0, sizeof(bksv));
>  
>  	/* HDCP spec states that we must retry the bksv if it is invalid */
> @@ -572,22 +548,11 @@ static int intel_hdcp_auth(struct intel_digital_port *intel_dig_port,
>  	}
>  
>  	/*
> -	 * Wait for R0' to become available. The spec says minimum 100ms from
> -	 * Aksv, but some monitors can take longer than this. So we are
> -	 * combinely waiting for 300mSec just to be sure in case of HDMI.
>  	 * DP HDCP Spec mandates the two more reattempt to read R0, incase
>  	 * of R0 mismatch.
> -	 *
> -	 * On DP, there's an R0_READY bit available but no such bit
> -	 * exists on HDMI. Since the upper-bound is the same, we'll just do
> -	 * the stupid thing instead of polling on one and not the other.
>  	 */
> -
>  	tries = 3;
>  	for (i = 0; i < tries; i++) {
> -		wait_remaining_ms_from_jiffies(r0_prime_gen_start,
> -					       100 * (i + 1));
> -
>  		ri.reg = 0;
>  		ret = shim->read_ri_prime(intel_dig_port, ri.shim);
>  		if (ret)
> @@ -749,6 +714,8 @@ int intel_hdcp_init(struct intel_connector *connector,
>  	mutex_init(&connector->hdcp_mutex);
>  	INIT_DELAYED_WORK(&connector->hdcp_check_work, intel_hdcp_check_work);
>  	INIT_WORK(&connector->hdcp_prop_work, intel_hdcp_prop_work);
> +
> +	init_completion(&connector->cp_irq_recved);
>  	return 0;
>  }
>  
> diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
> index f5d7bfb43006..532d13f91602 100644
> --- a/drivers/gpu/drm/i915/intel_hdmi.c
> +++ b/drivers/gpu/drm/i915/intel_hdmi.c
> @@ -1007,6 +1007,9 @@ int intel_hdmi_hdcp_read_ri_prime(struct intel_digital_port *intel_dig_port,
>  				  u8 *ri_prime)
>  {
>  	int ret;
> +
> +	wait_remaining_ms_from_jiffies(jiffies, 100);
> +
>  	ret = intel_hdmi_hdcp_read(intel_dig_port, DRM_HDCP_DDC_RI_PRIME,
>  				   ri_prime, DRM_HDCP_RI_LEN);
>  	if (ret)
> @@ -1027,6 +1030,29 @@ int intel_hdmi_hdcp_read_ksv_ready(struct intel_digital_port *intel_dig_port,
>  		return ret;
>  	}
>  	*ksv_ready = val & DRM_HDCP_DDC_BCAPS_KSV_FIFO_READY;
> +
> +	return 0;
> +}
> +
> +static
> +int intel_hdmi_hdcp_ksv_ready(struct intel_digital_port *intel_dig_port)
> +{
> +	int ret, read_ret;
> +	bool ksv_ready;
> +
> +	/* Poll for ksv list ready (spec says max time allowed is 5s) */
> +	ret = __wait_for(read_ret =
> +			 intel_hdmi_hdcp_read_ksv_ready(intel_dig_port,
> +							&ksv_ready),
> +			 read_ret || ksv_ready, 5 * 1000 * 1000, 1000,
> +			 100 * 1000);
> +	if (ret)
> +		return ret;
> +	if (read_ret)
> +		return read_ret;
> +	if (!ksv_ready)
> +		return -ETIMEDOUT;
> +
>  	return 0;
>  }
>  
> @@ -1112,7 +1138,7 @@ static const struct intel_hdcp_shim intel_hdmi_hdcp_shim = {
>  	.read_bstatus = intel_hdmi_hdcp_read_bstatus,
>  	.repeater_present = intel_hdmi_hdcp_repeater_present,
>  	.read_ri_prime = intel_hdmi_hdcp_read_ri_prime,
> -	.read_ksv_ready = intel_hdmi_hdcp_read_ksv_ready,
> +	.wait_for_ksv_ready = intel_hdmi_hdcp_ksv_ready,
>  	.read_ksv_fifo = intel_hdmi_hdcp_read_ksv_fifo,
>  	.read_v_prime_part = intel_hdmi_hdcp_read_v_prime_part,
>  	.toggle_signalling = intel_hdmi_hdcp_toggle_signalling,
> -- 
> 2.7.4
> 

-- 
Sean Paul, Software Engineer, Google / Chromium OS


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