[PATCH v2 27/42] drm/i915: Enable and Disable HDCP2.2 port encryption

[Ramalingam C]

Implements the enable and disable functions for HDCP2.2 encryption
of the PORT.

v2:
  intel_wait_for_register is used instead of wait_for. [Chris Wilson]

Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
---
 drivers/gpu/drm/i915/intel_hdcp.c | 54 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_hdcp.c b/drivers/gpu/drm/i915/intel_hdcp.c
index 53314f8e491a..38cecf533cb9 100644
--- a/drivers/gpu/drm/i915/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/intel_hdcp.c
@@ -19,6 +19,7 @@
 					 (enum physical_port) (port))
 #define KEY_LOAD_TRIES	5
 #define HDCP2_LC_RETRY_CNT		3
+#define TIME_FOR_ENCRYPT_STATUS_CHANGE	32
 
 static int intel_hdcp_poll_ksv_fifo(struct intel_digital_port *intel_dig_port,
 				    const struct intel_hdcp_shim *shim)
@@ -1330,3 +1331,56 @@ static int hdcp2_authenticate_sink(struct intel_connector *connector)
 
 	return ret;
 }
+
+static int hdcp2_enable_encryption(struct intel_connector *connector)
+{
+	struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
+	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+	struct intel_hdcp *hdcp = &connector->hdcp;
+	enum port port = connector->encoder->port;
+	int ret;
+
+	if (I915_READ(HDCP2_STATUS_DDI(port)) & LINK_ENCRYPTION_STATUS)
+		return 0;
+
+	if (hdcp->hdcp_shim->toggle_signalling)
+		hdcp->hdcp_shim->toggle_signalling(intel_dig_port, true);
+
+	if (I915_READ(HDCP2_STATUS_DDI(port)) & LINK_AUTH_STATUS) {
+
+		/* Link is Authenticated. Now set for Encryption */
+		I915_WRITE(HDCP2_CTR_DDI(port),
+			   I915_READ(HDCP2_CTR_DDI(port)) |
+			   CTL_LINK_ENCRYPTION_REQ);
+	}
+
+	ret = intel_wait_for_register(dev_priv, HDCP2_STATUS_DDI(port),
+				      LINK_ENCRYPTION_STATUS,
+				      LINK_ENCRYPTION_STATUS,
+				      TIME_FOR_ENCRYPT_STATUS_CHANGE);
+	return ret;
+}
+
+static int hdcp2_disable_encryption(struct intel_connector *connector)
+{
+	struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
+	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+	struct intel_hdcp *hdcp = &connector->hdcp;
+	enum port port = connector->encoder->port;
+	int ret;
+
+	if (!(I915_READ(HDCP2_STATUS_DDI(port)) & LINK_ENCRYPTION_STATUS))
+		return 0;
+
+	I915_WRITE(HDCP2_CTR_DDI(port),
+		   I915_READ(HDCP2_CTR_DDI(port)) & ~CTL_LINK_ENCRYPTION_REQ);
+
+	ret = intel_wait_for_register(dev_priv, HDCP2_STATUS_DDI(port),
+				      LINK_ENCRYPTION_STATUS, 0x0,
+				      TIME_FOR_ENCRYPT_STATUS_CHANGE);
+
+	if (hdcp->hdcp_shim->toggle_signalling)
+		hdcp->hdcp_shim->toggle_signalling(intel_dig_port, false);
+
+	return ret;
+}
-- 
2.7.4