[PATCH v6 17/35] drm/i915: Check HDCP 1.4 and 2.2 link on CP_IRQ

[Ramalingam C]

On Wednesday 01 August 2018 04:32 PM, Shankar, Uma wrote:
>
>> -----Original Message-----
>> From: C, Ramalingam
>> Sent: Saturday, July 14, 2018 8:45 AM
>> To: intel-gfx at lists.freedesktop.org; dri-devel at lists.freedesktop.org;
>> daniel at ffwll.ch; seanpaul at chromium.org; Winkler, Tomas
>> <tomas.winkler at intel.com>; Usyskin, Alexander <alexander.usyskin at intel.com>;
>> Shankar, Uma <uma.shankar at intel.com>
>> Cc: Sharma, Shashank <shashank.sharma at intel.com>; C, Ramalingam
>> <ramalingam.c at intel.com>
>> Subject: [PATCH v6 17/35] drm/i915: Check HDCP 1.4 and 2.2 link on CP_IRQ
>>
>> On DP HDCP1.4 and 2.2, when CP_IRQ is received, start the link integrity check
>> for the HDCP version that is enabled.
>>
>> v2:
>>   Rebased. Function name is changed.
>> v3:
>>   No Changes.
>> v4:
>>   No Changes.
>> v5:
>>   No Changes.
>> v6:
>>   %s/_in_force/_in_use [Sean Paul]
>>
>> Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
>> cc: Sean Paul <seanpaul at chromium.org>
>> Reviewed-by: Sean Paul <seanpaul at chromium.org>
>> ---
>> drivers/gpu/drm/i915/intel_dp.c   |  2 +-
>> drivers/gpu/drm/i915/intel_drv.h  |  2 +-  drivers/gpu/drm/i915/intel_hdcp.c | 31
>> ++++++++++++++++++++++++++++++-
>> 3 files changed, 32 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
>> index 0d31c9c286e9..6dcb09430fb5 100644
>> --- a/drivers/gpu/drm/i915/intel_dp.c
>> +++ b/drivers/gpu/drm/i915/intel_dp.c
>> @@ -4484,7 +4484,7 @@ 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)
>> -			intel_hdcp_check_link(intel_dp->attached_connector);
>> +			intel_hdcp_handle_cp_irq(intel_dp-
>>> attached_connector);
>> 		if (sink_irq_vector & DP_SINK_SPECIFIC_IRQ)
>> 			DRM_DEBUG_DRIVER("Sink specific irq unhandled\n");
>> 	}
>> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
>> index ce4679a0b530..82cda9a5aae3 100644
>> --- a/drivers/gpu/drm/i915/intel_drv.h
>> +++ b/drivers/gpu/drm/i915/intel_drv.h
>> @@ -1969,10 +1969,10 @@ int intel_hdcp_init(struct intel_connector
>> *connector,
>> 		    bool hdcp2_supported);
>> int intel_hdcp_enable(struct intel_connector *connector);  int
>> intel_hdcp_disable(struct intel_connector *connector); -int
>> intel_hdcp_check_link(struct intel_connector *connector);  bool
>> is_hdcp_supported(struct drm_i915_private *dev_priv, enum port port);  int
>> intel_hdcp_component_init(struct drm_i915_private *dev_priv);  bool
>> is_hdcp2_supported(struct drm_i915_private *dev_priv);
>> +void intel_hdcp_handle_cp_irq(struct intel_connector *connector);
>>
>> /* intel_psr.c */
>> #define CAN_PSR(dev_priv) (HAS_PSR(dev_priv) && dev_priv->psr.sink_support)
>> diff --git a/drivers/gpu/drm/i915/intel_hdcp.c
>> b/drivers/gpu/drm/i915/intel_hdcp.c
>> index 6afce9ae09ed..66d47240336f 100644
>> --- a/drivers/gpu/drm/i915/intel_hdcp.c
>> +++ b/drivers/gpu/drm/i915/intel_hdcp.c
>> @@ -32,6 +32,7 @@ int intel_hdcp_read_valid_bksv(struct intel_digital_port
>> *intel_dig_port,
>> 			       const struct intel_hdcp_shim *shim, u8 *bksv);  static
>> struct intel_digital_port *conn_to_dig_port(struct intel_connector *connector);
>> +static int intel_hdcp_check_link(struct intel_connector *connector);
>>
>> /* Is HDCP1.4 capable on Platform and Panel */  static bool
>> intel_hdcp_capable(struct intel_connector *connector) @@ -66,6 +67,26 @@
>> static bool intel_hdcp2_capable(struct intel_connector *connector)
>> 	return capable;
>> }
>>
>> +static inline bool intel_hdcp_in_use(struct intel_connector *connector)
>> +{
>> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
>> +	enum port port = connector->encoder->port;
>> +	u32 reg;
>> +
>> +	reg = I915_READ(PORT_HDCP_STATUS(port));
>> +	return reg & (HDCP_STATUS_AUTH | HDCP_STATUS_ENC); }
>> +
>> +static inline bool intel_hdcp2_in_use(struct intel_connector
>> +*connector) {
>> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
>> +	enum port port = connector->encoder->port;
>> +	u32 reg;
>> +
>> +	reg = I915_READ(HDCP2_STATUS_DDI(port));
>> +	return reg & (LINK_ENCRYPTION_STATUS | LINK_AUTH_STATUS); }
>> +
>> static int intel_hdcp_poll_ksv_fifo(struct intel_digital_port *intel_dig_port,
>> 				    const struct intel_hdcp_shim *shim)  { @@ -
>> 928,7 +949,7 @@ void intel_hdcp_atomic_check(struct drm_connector
>> *connector,  }
>>
>> /* Implements Part 3 of the HDCP authorization procedure */ -int
>> intel_hdcp_check_link(struct intel_connector *connector)
>> +static int intel_hdcp_check_link(struct intel_connector *connector)
>> {
>> 	struct intel_hdcp *hdcp = &connector->hdcp;
>> 	struct drm_i915_private *dev_priv = connector->base.dev->dev_private;
>> @@ -1821,3 +1842,11 @@ static void intel_hdcp2_check_work(struct
>> work_struct *work)
>> 		schedule_delayed_work(&hdcp->hdcp2_check_work,
>> 				      DRM_HDCP2_CHECK_PERIOD_MS);
>> }
>> +
>> +void intel_hdcp_handle_cp_irq(struct intel_connector *connector) {
>> +	if (intel_hdcp_in_use(connector))
>> +		intel_hdcp_check_link(connector);
> Handle the return value. Atleast a print in case of link failures through this
> path.
>
>> +	else if (intel_hdcp2_in_use(connector))
>> +		intel_hdcp2_check_link(connector);
> Same here.
Uma,

At this handler of CP_IRQ, we don't want to handle the return of the 
Link integrity check.
As CP_IRQ could be generated for LINK_INTEGRITY_FAILURE and REAUTH_REQ 
and which
are handled in the check_link()

And if reauth(Disable -> Enable) fails we have nothing to do. So we need 
not handle it.
Errors are already logged within check_link().

--Ram.
> With above fixed.
> Reviewed-by: Uma Shankar <uma.shankar at intel.com>
>
>> +}
>> --
>> 2.7.4