Re: [PATCH v6 09/35] drm/i915: Initialize HDCP2.2 and its MEI interface

From: Ramalingam C <ramalingam.c@intel.com>
To: "Shankar, Uma" <uma.shankar@intel.com>,
	"intel-gfx@lists.freedesktop.org"
	<intel-gfx@lists.freedesktop.org>,
	"dri-devel@lists.freedesktop.org"
	<dri-devel@lists.freedesktop.org>,
	"daniel@ffwll.ch" <daniel@ffwll.ch>,
	"seanpaul@chromium.org" <seanpaul@chromium.org>,
	"Winkler, Tomas" <tomas.winkler@intel.com>,
	"Usyskin, Alexander" <alexander.usyskin@intel.com>
Subject: Re: [PATCH v6 09/35] drm/i915: Initialize HDCP2.2 and its MEI interface
Date: Wed, 1 Aug 2018 17:12:01 +0530	[thread overview]
Message-ID: <7bdf6233-5cd5-9f45-e194-7e87bfece26c@intel.com> (raw)
In-Reply-To: <E7C9878FBA1C6D42A1CA3F62AEB6945F7F36210A@BGSMSX104.gar.corp.intel.com>


On Wednesday 01 August 2018 01:11 AM, Shankar, Uma wrote:
>> -----Original Message-----
>> From: C, Ramalingam
>> Sent: Saturday, July 14, 2018 8:45 AM
>> To: intel-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org;
>> daniel@ffwll.ch; seanpaul@chromium.org; Winkler, Tomas
>> <tomas.winkler@intel.com>; Usyskin, Alexander <alexander.usyskin@intel.com>;
>> Shankar, Uma <uma.shankar@intel.com>
>> Cc: Sharma, Shashank <shashank.sharma@intel.com>; C, Ramalingam
>> <ramalingam.c@intel.com>
>> Subject: [PATCH v6 09/35] drm/i915: Initialize HDCP2.2 and its MEI interface
>>
>> Initialize HDCP2.2 support. This includes the mei interface initialization along with
>> required component registration.
>>
>> v2:
>>   mei interface handle is protected with mutex. [Chris Wilson]
>> v3:
>>   Notifiers are used for the mei interface state.
>> v4:
>>   Poll for mei client device state
>>   Error msg for out of mem [Uma]
>>   Inline req for init function removed [Uma]
>> v5:
>>   Rebase as Part of reordering.
>>   Component is used for the I915 and MEI_HDCP interface [Daniel]
>> v6:
>>   HDCP2.2 uses the I915 component master to communicate with mei_hdcp
>> 	- [Daniel]
>>   Required HDCP2.2 variables defined [Sean Paul]
>>
>> Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
>> ---
>> drivers/gpu/drm/i915/intel_dp.c   |  3 +-
>> drivers/gpu/drm/i915/intel_drv.h  | 23 +++++++++++-
>> drivers/gpu/drm/i915/intel_hdcp.c | 77
>> ++++++++++++++++++++++++++++++++++++++-
>> drivers/gpu/drm/i915/intel_hdmi.c |  2 +-
>> include/drm/i915_component.h      | 60 ++++++++++++++++++++++++++++++
>> 5 files changed, 161 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
>> index 5be07e1d816d..12eb5bd33b7e 100644
>> --- a/drivers/gpu/drm/i915/intel_dp.c
>> +++ b/drivers/gpu/drm/i915/intel_dp.c
>> @@ -6406,7 +6406,8 @@ intel_dp_init_connector(struct intel_digital_port
>> *intel_dig_port,
>> 	intel_dp_add_properties(intel_dp, connector);
>>
>> 	if (is_hdcp_supported(dev_priv, port) && !intel_dp_is_edp(intel_dp)) {
>> -		int ret = intel_hdcp_init(intel_connector, &intel_dp_hdcp_shim);
>> +		int ret = intel_hdcp_init(intel_connector, &intel_dp_hdcp_shim,
>> +					  false);
>> 		if (ret)
>> 			DRM_DEBUG_KMS("HDCP init failed, skipping.\n");
>> 	}
>> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
>> index c32665136d5d..38262792813a 100644
>> --- a/drivers/gpu/drm/i915/intel_drv.h
>> +++ b/drivers/gpu/drm/i915/intel_drv.h
>> @@ -29,6 +29,7 @@
>> #include <linux/i2c.h>
>> #include <linux/hdmi.h>
>> #include <linux/sched/clock.h>
>> +#include <linux/mei_hdcp.h>
>> #include <drm/i915_drm.h>
>> #include "i915_drv.h"
>> #include <drm/drm_crtc.h>
>> @@ -376,6 +377,9 @@ struct intel_hdcp_shim {
>> 	/* Detects panel's hdcp capability. This is optional for HDMI. */
>> 	int (*hdcp_capable)(struct intel_digital_port *intel_dig_port,
>> 			    bool *hdcp_capable);
>> +
>> +	/* Detects the HDCP protocol(DP/HDMI) required on the port */
>> +	enum hdcp_protocol (*hdcp_protocol)(void);
>> };
>>
>> struct intel_hdcp {
>> @@ -385,6 +389,20 @@ struct intel_hdcp {
>> 	uint64_t value;
>> 	struct delayed_work check_work;
>> 	struct work_struct prop_work;
>> +
>> +	/* HDCP2.2 related definitions */
>> +	/* Flag indicates whether this connector supports HDCP2.2 or not. */
>> +	bool hdcp2_supported;
>> +
>> +	/*
>> +	 * Content Stream Type defined by content owner. TYPE0(0x0) content
>> can
>> +	 * flow in the link protected by HDCP2.2 or HDCP1.4, where as
>> TYPE1(0x1)
>> +	 * content can flow only through a link protected by HDCP2.2.
>> +	 */
>> +	u8 content_type;
>> +
>> +	/* mei interface related information */
>> +	struct mei_hdcp_data mei_data;
>> };
>>
>> struct intel_connector {
>> @@ -1903,11 +1921,14 @@ void intel_hdcp_atomic_check(struct
>> drm_connector *connector,
>> 			     struct drm_connector_state *old_state,
>> 			     struct drm_connector_state *new_state);  int
>> intel_hdcp_init(struct intel_connector *connector,
>> -		    const struct intel_hdcp_shim *hdcp_shim);
>> +		    const struct intel_hdcp_shim *hdcp_shim,
>> +		    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);
>>
>> /* 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 55bc4d423187..cfe915c3f336 100644
>> --- a/drivers/gpu/drm/i915/intel_hdcp.c
>> +++ b/drivers/gpu/drm/i915/intel_hdcp.c
>> @@ -8,13 +8,19 @@
>>
>> #include <drm/drmP.h>
>> #include <drm/drm_hdcp.h>
>> +#include <drm/i915_component.h>
>> #include <linux/i2c.h>
>> #include <linux/random.h>
>> +#include <linux/component.h>
>>
>> #include "intel_drv.h"
>> #include "i915_reg.h"
>>
>> #define KEY_LOAD_TRIES	5
>> +#define GET_MEI_DDI_INDEX(port)		(((port) == PORT_A) ? DDI_A : \
>> +					 (enum hdcp_physical_port)(port))
>> +
>> +static int intel_hdcp2_init(struct intel_connector *connector);
>>
>> static int intel_hdcp_poll_ksv_fifo(struct intel_digital_port *intel_dig_port,
>> 				    const struct intel_hdcp_shim *shim) @@ -
>> 744,11 +750,15 @@ bool is_hdcp_supported(struct drm_i915_private *dev_priv,
>> enum port port)  }
>>
>> int intel_hdcp_init(struct intel_connector *connector,
>> -		    const struct intel_hdcp_shim *shim)
>> +		    const struct intel_hdcp_shim *shim,
>> +		    bool hdcp2_supported)
>> {
>> 	struct intel_hdcp *hdcp = &connector->hdcp;
>> 	int ret;
>>
>> +	if (!shim)
>> +		return -EINVAL;
>> +
>> 	ret = drm_connector_attach_content_protection_property(
>> 			&connector->base);
>> 	if (ret)
>> @@ -758,6 +768,10 @@ int intel_hdcp_init(struct intel_connector *connector,
>> 	mutex_init(&hdcp->mutex);
>> 	INIT_DELAYED_WORK(&hdcp->check_work, intel_hdcp_check_work);
>> 	INIT_WORK(&hdcp->prop_work, intel_hdcp_prop_work);
>> +
>> +	if (hdcp2_supported)
>> +		intel_hdcp2_init(connector);
>> +
>> 	return 0;
>> }
>>
>> @@ -895,3 +909,64 @@ int intel_hdcp_check_link(struct intel_connector
>> *connector)
>> 	mutex_unlock(&hdcp->mutex);
>> 	return ret;
>> }
>> +
>> +static int i915_hdcp_component_match(struct device *dev, void *data) {
>> +	return !strcmp(dev->driver->name, "mei_hdcp"); }
>> +
>> +static int initialize_mei_hdcp_data(struct intel_connector *connector)
>> +{
>> +	struct intel_hdcp *hdcp = &connector->hdcp;
>> +	struct mei_hdcp_data *data = &hdcp->mei_data;
>> +	enum port port;
>> +
>> +	if (connector->encoder) {
>> +		port = connector->encoder->port;
>> +		data->port = GET_MEI_DDI_INDEX(port);
>> +	}
>> +
>> +	data->port_type = INTEGRATED;
>> +	data->protocol = hdcp->shim->hdcp_protocol();
>> +
>> +	data->k = 1;
>> +	if (!data->streams)
>> +		data->streams = kcalloc(data->k,
>> +					sizeof(struct hdcp2_streamid_type),
>> +					GFP_KERNEL);
>> +	if (!data->streams) {
>> +		DRM_ERROR("Out of Memory\n");
>> +		return -ENOMEM;
>> +	}
>> +
>> +	data->streams[0].stream_id = 0;
>> +	data->streams[0].stream_type = hdcp->content_type;
>> +
>> +	return 0;
>> +}
>> +
>> +bool is_hdcp2_supported(struct drm_i915_private *dev_priv) {
>> +	return ((INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv) ||
>> +		 IS_KABYLAKE(dev_priv)) &&
>> IS_ENABLED(CONFIG_INTEL_MEI_HDCP));
>> +}
>> +
>> +static int intel_hdcp2_init(struct intel_connector *connector) {
> The caller doesn't care for the return. Either make it void or handle the error.
> I recommend later would be good.
Make sense return void, as no need to handle the error state at caller.
>> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
>> +	struct intel_hdcp *hdcp = &connector->hdcp;
>> +	int ret;
>> +
>> +	WARN_ON(!is_hdcp2_supported(dev_priv));
> Don't think this extra check is required, since it's called only from 1 place with
> hdcp2 check already taken care of. This can be dropped.
I believe this extra check should be ok. Being more paranoid just to 
catch if we are here by mistake.
>
>> +	ret = initialize_mei_hdcp_data(connector);
>> +	if (ret)
>> +		goto exit;
>> +
>> +	component_match_add(dev_priv->drm.dev, &dev_priv->master_match,
>> +			    i915_hdcp_component_match, dev_priv);
>> +
>> +	hdcp->hdcp2_supported = true;
>> +
>> +exit:
>> +	return ret;
>> +}
>> diff --git a/drivers/gpu/drm/i915/intel_hdmi.c
>> b/drivers/gpu/drm/i915/intel_hdmi.c
>> index 8363fbd18ee8..7988f958d835 100644
>> --- a/drivers/gpu/drm/i915/intel_hdmi.c
>> +++ b/drivers/gpu/drm/i915/intel_hdmi.c
>> @@ -2366,7 +2366,7 @@ void intel_hdmi_init_connector(struct
>> intel_digital_port *intel_dig_port,
>>
>> 	if (is_hdcp_supported(dev_priv, port)) {
>> 		int ret = intel_hdcp_init(intel_connector,
>> -					  &intel_hdmi_hdcp_shim);
>> +					  &intel_hdmi_hdcp_shim, false);
> A comment mentioning the reason for hdcp2 supported to be false would be good.
This is just intermediate state. later patch will replace this with 
connector's hdcp2.2 capability.
So I guess I will skip this comment.

--Ram
>
>> 		if (ret)
>> 			DRM_DEBUG_KMS("HDCP init failed, skipping.\n");
>> 	}
>> diff --git a/include/drm/i915_component.h b/include/drm/i915_component.h
>> index 52313bc227b2..f208a83ea2c9 100644
>> --- a/include/drm/i915_component.h
>> +++ b/include/drm/i915_component.h
>> @@ -24,6 +24,10 @@
>> #ifndef _I915_COMPONENT_H_
>> #define _I915_COMPONENT_H_
>>
>> +#include <linux/mei_cl_bus.h>
>> +#include <linux/mei_hdcp.h>
>> +#include <drm/drm_hdcp.h>
>> +
>> /* MAX_PORT is the number of port
>>   * It must be sync with I915_MAX_PORTS defined i915_drv.h
>>   */
>> @@ -121,6 +125,54 @@ struct i915_audio_component {
>> 	const struct i915_audio_component_audio_ops *audio_ops;  };
>>
>> +struct i915_hdcp_component_ops {
>> +	/**
>> +	 * @owner: mei_hdcp module
>> +	 */
>> +	struct module *owner;
>> +	int (*initiate_hdcp2_session)(struct mei_cl_device *cldev,
>> +				      struct mei_hdcp_data *data,
>> +				      struct hdcp2_ake_init *ake_data);
>> +	int
>> +	(*verify_receiver_cert_prepare_km)(struct mei_cl_device *cldev,
>> +					   struct mei_hdcp_data *data,
>> +					   struct hdcp2_ake_send_cert *rx_cert,
>> +					   bool *km_stored,
>> +					   struct hdcp2_ake_no_stored_km
>> +								*ek_pub_km,
>> +					   size_t *msg_sz);
>> +	int (*verify_hprime)(struct mei_cl_device *cldev,
>> +			     struct mei_hdcp_data *data,
>> +			     struct hdcp2_ake_send_hprime *rx_hprime);
>> +	int (*store_pairing_info)(struct mei_cl_device *cldev,
>> +				  struct mei_hdcp_data *data,
>> +				  struct hdcp2_ake_send_pairing_info
>> +								*pairing_info);
>> +	int (*initiate_locality_check)(struct mei_cl_device *cldev,
>> +				       struct mei_hdcp_data *data,
>> +				       struct hdcp2_lc_init *lc_init_data);
>> +	int (*verify_lprime)(struct mei_cl_device *cldev,
>> +			     struct mei_hdcp_data *data,
>> +			     struct hdcp2_lc_send_lprime *rx_lprime);
>> +	int (*get_session_key)(struct mei_cl_device *cldev,
>> +			       struct mei_hdcp_data *data,
>> +			       struct hdcp2_ske_send_eks *ske_data);
>> +	int
>> +	(*repeater_check_flow_prepare_ack)(struct mei_cl_device *cldev,
>> +					   struct mei_hdcp_data *data,
>> +					   struct hdcp2_rep_send_receiverid_list
>> +								*rep_topology,
>> +					   struct hdcp2_rep_send_ack
>> +
>> 	*rep_send_ack);
>> +	int (*verify_mprime)(struct mei_cl_device *cldev,
>> +			     struct mei_hdcp_data *data,
>> +			     struct hdcp2_rep_stream_ready *stream_ready);
>> +	int (*enable_hdcp_authentication)(struct mei_cl_device *cldev,
>> +					  struct mei_hdcp_data *data);
>> +	int (*close_hdcp_session)(struct mei_cl_device *cldev,
>> +				  struct mei_hdcp_data *data);
>> +};
>> +
>> /**
>>   * struct i915_component_master - Used for communication between i915
>>   * and any other drivers for the services of different feature.
>> @@ -131,6 +183,14 @@ struct i915_component_master {
>> 	 * removing the reference to mei_cldev.
>> 	 */
>> 	struct device *i915_kdev;
>> +	/**
>> +	 * @mei_cldev: mei client device, used as parameter for ops
>> +	 */
>> +	struct mei_cl_device *mei_cldev;
>> +	/**
>> +	 * @ops: Ops implemented by mei_hdcp driver, used by i915 driver.
>> +	 */
>> +	const struct i915_hdcp_component_ops *hdcp_ops;
>>
>> 	/*
>> 	 * Add here the interface details between I915 and interested modules.
>> --
>> 2.7.4

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx