RE: [PATCH v10 07/40] drm/i915: hdcp1.4 CP_IRQ handling and SW encryption tracking

-----Original Message----- From: C, Ramalingam Sent: Thursday, January 31, 2019 12:29 PM To: intel-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org; daniel.vetter@ffwll.ch; Winkler, Tomas tomas.winkler@intel.com; Shankar, Uma uma.shankar@intel.com Cc: C, Ramalingam ramalingam.c@intel.com Subject: [PATCH v10 07/40] drm/i915: hdcp1.4 CP_IRQ handling and SW encryption tracking

"hdcp_encrypted" flag is defined to denote the HDCP1.4 encryption status. This SW tracking is used to determine the need for real hdcp1.4 disable and hdcp_check_link upon CP_IRQ.

On CP_IRQ we filter the CP_IRQ related to the states like Link failure and reauthentication req etc and handle them in hdcp_check_link. CP_IRQ corresponding to the authentication msg availability are ignored.

WARN_ON is added for the abrupt stop of HDCP encryption of a port.

v2: bool is used in struct for the cleaner coding. [Daniel] check_link work_fn is scheduled for cp_irq handling [Daniel]

Signed-off-by: Ramalingam C ramalingam.c@intel.com

drivers/gpu/drm/i915/intel_dp.c | 2 +- drivers/gpu/drm/i915/intel_drv.h | 5 ++- drivers/gpu/drm/i915/intel_hdcp.c | 73 ++++++++++++++++++++++++++++----------- 3 files changed, 58 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 815ee68efa2f..9ce05819fc11 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -4776,7 +4776,7 @@ static void intel_dp_check_service_irq(struct intel_dp *intel_dp) intel_dp_handle_test_request(intel_dp);

if (val & DP_CP_IRQ)

• intel_hdcp_check_link(intel_dp->attached_connector);
  

• intel_hdcp_handle_cp_irq(intel_dp->attached_connector);
  
  

  if (val & 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 63e009286d5f..13a41e8cf4ff 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -399,6 +399,9 @@ struct intel_hdcp { struct delayed_work check_work; struct work_struct prop_work;

• /* HDCP1.4 Encryption status */
• bool hdcp_encrypted;
• /* HDCP2.2 related definitions */ /* Flag indicates whether this connector supports HDCP2.2 or not. */ bool hdcp2_supported;

@@ -2073,10 +2076,10 @@ 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); bool intel_hdcp_capable(struct intel_connector *connector); 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 e0bb5f32ba90..c1b057f1501b 100644 --- a/drivers/gpu/drm/i915/intel_hdcp.c +++ b/drivers/gpu/drm/i915/intel_hdcp.c @@ -74,6 +74,16 @@ bool intel_hdcp_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_ENC;

+}

static int intel_hdcp_poll_ksv_fifo(struct intel_digital_port *intel_dig_port, const struct intel_hdcp_shim *shim) { @@ - 668,6 +678,7 @@ static int _intel_hdcp_disable(struct intel_connector *connector) DRM_DEBUG_KMS("[%s:%d] HDCP is being disabled...\n", connector->base.name, connector->base.base.id);

• hdcp->hdcp_encrypted = false; I915_WRITE(PORT_HDCP_CONF(port), 0); if (intel_wait_for_register(dev_priv, PORT_HDCP_STATUS(port), ~0, 0, ENCRYPT_STATUS_CHANGE_TIMEOUT_MS)) {

@@ -713,8 +724,10 @@ static int _intel_hdcp_enable(struct intel_connector *connector) /* Incase of authentication failures, HDCP spec expects reauth. */ for (i = 0; i < tries; i++) { ret = intel_hdcp_auth(conn_to_dig_port(connector), hdcp-

...

shim);

• if (!ret)
  

• if (!ret) {
  

• 	hdcp->hdcp_encrypted = true;
  return 0;
  

• }
  
  

  DRM_DEBUG_KMS("HDCP Auth failure (%d)\n", ret);

@@ -741,16 +754,17 @@ int intel_hdcp_check_link(struct intel_connector *connector) enum port port = intel_dig_port->base.port; int ret = 0;

• if (!hdcp->shim)

• return -ENOENT;
  

• mutex_lock(&hdcp->mutex);

• if (hdcp->value == DRM_MODE_CONTENT_PROTECTION_UNDESIRED)

• /* Check_link valid only when HDCP1.4 is enabled */
• if (hdcp->value != DRM_MODE_CONTENT_PROTECTION_ENABLED ||

•    !hdcp->hdcp_encrypted) {
  

• ret = -EINVAL;
  

  goto out;
• }

• if (!(I915_READ(PORT_HDCP_STATUS(port)) & HDCP_STATUS_ENC)) {

• DRM_ERROR("%s:%d HDCP check failed: link is not
  

encrypted,%x\n",

• if (WARN_ON(!intel_hdcp_in_use(connector))) {

• DRM_ERROR("%s:%d HDCP link stopped encryption,%x\n",
    connector->base.name, connector->base.base.id,
    I915_READ(PORT_HDCP_STATUS(port)));
  

  ret = -ENXIO;

@@ -791,18 +805,6 @@ int intel_hdcp_check_link(struct intel_connector *connector) return ret; }

-static void intel_hdcp_check_work(struct work_struct *work) -{

• struct intel_hdcp *hdcp = container_of(to_delayed_work(work),

• 			       struct intel_hdcp,
  

• 			       check_work);
  

• struct intel_connector *connector = intel_hdcp_to_connector(hdcp);
• if (!intel_hdcp_check_link(connector))

• schedule_delayed_work(&hdcp->check_work,
  

• 		      DRM_HDCP_CHECK_PERIOD_MS);
  

-}

static void intel_hdcp_prop_work(struct work_struct *work) { struct intel_hdcp *hdcp = container_of(work, struct intel_hdcp, @@ - 1120,6 +1122,18 @@ int hdcp2_deauthenticate_port(struct intel_connector *connector) return hdcp2_close_mei_session(connector); }

+static void intel_hdcp_check_work(struct work_struct *work) {

Why this code movement for check_work. If not intentional no need for this change. With proper justification or this fixed.

Reviewed-by: Uma Shankar uma.shankar@intel.com

• struct intel_hdcp *hdcp = container_of(to_delayed_work(work),

• 			       struct intel_hdcp,
  

• 			       check_work);
  

• struct intel_connector *connector = intel_hdcp_to_connector(hdcp);
• if (!intel_hdcp_check_link(connector))

• schedule_delayed_work(&hdcp->check_work,
  

• 		      DRM_HDCP_CHECK_PERIOD_MS);
  

+}

static int i915_hdcp_component_bind(struct device *i915_kdev, struct device *mei_kdev, void *data) { @@ - 1288,7 +1302,8 @@ int intel_hdcp_disable(struct intel_connector *connector)

if (hdcp->value != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) { hdcp->value = DRM_MODE_CONTENT_PROTECTION_UNDESIRED;

• ret = _intel_hdcp_disable(connector);
  

• if (hdcp->hdcp_encrypted)
  

• 	ret = _intel_hdcp_disable(connector);
  

  }

  mutex_unlock(&hdcp->mutex);

@@ -1328,3 +1343,21 @@ void intel_hdcp_atomic_check(struct drm_connector *connector, new_state->crtc); crtc_state->mode_changed = true; }

+/* Handles the CP_IRQ raised from the DP HDCP sink */ void +intel_hdcp_handle_cp_irq(struct intel_connector *connector) {

• struct intel_hdcp *hdcp = &connector->hdcp;
• if (!hdcp->shim)

• return;
  

• /*

• * CP_IRQ could be triggered due to 1. HDCP2.2 auth msgs availability,
  

• * 2. link failure and 3. repeater reauth request. At present we dont
  

• * handle the CP_IRQ for the HDCP2.2 auth msg availability for read.
  

• * To handle other two causes for CP_IRQ we have the work_fn which is
  

• * scheduled here.
  

• */
  

• schedule_delayed_work(&hdcp->check_work, 0); }

-- 2.7.4