From 49a630b00bacb609d78ae137cbe9e8de1cd5c692 Mon Sep 17 00:00:00 2001 From: Ramalingam C Date: Sat, 16 Feb 2019 23:06:53 +0530 Subject: [PATCH] drm/i915: Enable and Disable of HDCP2.2 Considering that HDCP2.2 is more secure than HDCP1.4, When a setup supports HDCP2.2 and HDCP1.4, HDCP2.2 will be enabled. When HDCP2.2 enabling fails and HDCP1.4 is supported, HDCP1.4 is enabled. This change implements a sequence of enabling and disabling of HDCP2.2 authentication and HDCP2.2 port encryption. v2: Included few optimization suggestions [Chris Wilson] Commit message is updated as per the rebased version. intel_wait_for_register is used instead of wait_for. [Chris Wilson] v3: Extra comment added and Style issue fixed [Uma] v4: Rebased as part of patch reordering. HDCP2 encryption status is tracked. HW state check is moved into WARN_ON [Daniel] v5: Redefined the mei service functions as per comp redesign. Merged patches related to hdcp2.2 enabling and disabling [Sean Paul]. Required shim functionality is defined [Sean Paul] v6: Return values are handles [Uma] Realigned the code. Check for comp_master is removed. v7: HDCP2.2 is attempted only if mei interface is up. Adjust to the new interface Avoid bool usage in struct [Tomas] v8: mei_binded status check is removed. %s/hdcp2_in_use/hdcp2_encrypted v9: bool is used in struct intel_hdcp. [Daniel] v10: panel is replaced with sink [Uma] Mei interface decided the hdcp2_capability. WARN_ON if hdcp_enable is called when hdcp state is ENABLED. Reviewed-by Uma. Signed-off-by: Ramalingam C Reviewed-by: Daniel Vetter Reviewed-by: Uma Shankar Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/1550338640-17470-7-git-send-email-ramalingam.c@intel.com --- drivers/gpu/drm/i915/intel_drv.h | 7 + drivers/gpu/drm/i915/intel_hdcp.c | 212 ++++++++++++++++++++++++++++-- 2 files changed, 205 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index aaddde44b270..7fcaa3ba538c 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -399,6 +399,10 @@ struct intel_hdcp_shim { /* HDCP adaptation(DP/HDMI) required on the port */ enum hdcp_wired_protocol protocol; + + /* Detects whether sink is HDCP2.2 capable */ + int (*hdcp_2_2_capable)(struct intel_digital_port *intel_dig_port, + bool *capable); }; struct intel_hdcp { @@ -416,6 +420,9 @@ struct intel_hdcp { /* Flag indicates whether this connector supports HDCP2.2 or not. */ bool hdcp2_supported; + /* HDCP2.2 Encryption status */ + bool hdcp2_encrypted; + /* * 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) diff --git a/drivers/gpu/drm/i915/intel_hdcp.c b/drivers/gpu/drm/i915/intel_hdcp.c index 66e3850a57a0..0b6ccb3d24fe 100644 --- a/drivers/gpu/drm/i915/intel_hdcp.c +++ b/drivers/gpu/drm/i915/intel_hdcp.c @@ -74,6 +74,32 @@ bool intel_hdcp_capable(struct intel_connector *connector) return capable; } +/* Is HDCP2.2 capable on Platform and Sink */ +static bool intel_hdcp2_capable(struct intel_connector *connector) +{ + struct drm_i915_private *dev_priv = to_i915(connector->base.dev); + struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector); + struct intel_hdcp *hdcp = &connector->hdcp; + bool capable = false; + + /* I915 support for HDCP2.2 */ + if (!hdcp->hdcp2_supported) + return false; + + /* MEI interface is solid */ + mutex_lock(&dev_priv->hdcp_comp_mutex); + if (!dev_priv->hdcp_comp_added || !dev_priv->hdcp_master) { + mutex_unlock(&dev_priv->hdcp_comp_mutex); + return false; + } + mutex_unlock(&dev_priv->hdcp_comp_mutex); + + /* Sink's capability for HDCP2.2 */ + hdcp->shim->hdcp_2_2_capable(intel_dig_port, &capable); + + return capable; +} + static inline bool intel_hdcp_in_use(struct intel_connector *connector) { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); @@ -1094,8 +1120,7 @@ int hdcp2_authenticate_port(struct intel_connector *connector) return ret; } -static __attribute__((unused)) -int hdcp2_close_mei_session(struct intel_connector *connector) +static int hdcp2_close_mei_session(struct intel_connector *connector) { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); struct i915_hdcp_comp_master *comp; @@ -1116,12 +1141,157 @@ int hdcp2_close_mei_session(struct intel_connector *connector) return ret; } -static __attribute__((unused)) -int hdcp2_deauthenticate_port(struct intel_connector *connector) +static int hdcp2_deauthenticate_port(struct intel_connector *connector) { return hdcp2_close_mei_session(connector); } +static int hdcp2_authenticate_sink(struct intel_connector *connector) +{ + DRM_ERROR("Sink authentication is done in subsequent patches\n"); + + return -EINVAL; +} + +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; + + WARN_ON(I915_READ(HDCP2_STATUS_DDI(port)) & LINK_ENCRYPTION_STATUS); + + if (hdcp->shim->toggle_signalling) { + ret = hdcp->shim->toggle_signalling(intel_dig_port, true); + if (ret) { + DRM_ERROR("Failed to enable HDCP signalling. %d\n", + ret); + return ret; + } + } + + if (I915_READ(HDCP2_STATUS_DDI(port)) & LINK_AUTH_STATUS) { + /* Link is Authenticated. Now set for Encryption */ + I915_WRITE(HDCP2_CTL_DDI(port), + I915_READ(HDCP2_CTL_DDI(port)) | + CTL_LINK_ENCRYPTION_REQ); + } + + ret = intel_wait_for_register(dev_priv, HDCP2_STATUS_DDI(port), + LINK_ENCRYPTION_STATUS, + LINK_ENCRYPTION_STATUS, + ENCRYPT_STATUS_CHANGE_TIMEOUT_MS); + + 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; + + WARN_ON(!(I915_READ(HDCP2_STATUS_DDI(port)) & LINK_ENCRYPTION_STATUS)); + + I915_WRITE(HDCP2_CTL_DDI(port), + I915_READ(HDCP2_CTL_DDI(port)) & ~CTL_LINK_ENCRYPTION_REQ); + + ret = intel_wait_for_register(dev_priv, HDCP2_STATUS_DDI(port), + LINK_ENCRYPTION_STATUS, 0x0, + ENCRYPT_STATUS_CHANGE_TIMEOUT_MS); + if (ret == -ETIMEDOUT) + DRM_DEBUG_KMS("Disable Encryption Timedout"); + + if (hdcp->shim->toggle_signalling) { + ret = hdcp->shim->toggle_signalling(intel_dig_port, false); + if (ret) { + DRM_ERROR("Failed to disable HDCP signalling. %d\n", + ret); + return ret; + } + } + + return ret; +} + +static int hdcp2_authenticate_and_encrypt(struct intel_connector *connector) +{ + int ret, i, tries = 3; + + for (i = 0; i < tries; i++) { + ret = hdcp2_authenticate_sink(connector); + if (!ret) + break; + + /* Clearing the mei hdcp session */ + DRM_DEBUG_KMS("HDCP2.2 Auth %d of %d Failed.(%d)\n", + i + 1, tries, ret); + if (hdcp2_deauthenticate_port(connector) < 0) + DRM_DEBUG_KMS("Port deauth failed.\n"); + } + + if (i != tries) { + /* + * Ensuring the required 200mSec min time interval between + * Session Key Exchange and encryption. + */ + msleep(HDCP_2_2_DELAY_BEFORE_ENCRYPTION_EN); + ret = hdcp2_enable_encryption(connector); + if (ret < 0) { + DRM_DEBUG_KMS("Encryption Enable Failed.(%d)\n", ret); + if (hdcp2_deauthenticate_port(connector) < 0) + DRM_DEBUG_KMS("Port deauth failed.\n"); + } + } + + return ret; +} + +static int _intel_hdcp2_enable(struct intel_connector *connector) +{ + struct intel_hdcp *hdcp = &connector->hdcp; + int ret; + + DRM_DEBUG_KMS("[%s:%d] HDCP2.2 is being enabled. Type: %d\n", + connector->base.name, connector->base.base.id, + hdcp->content_type); + + ret = hdcp2_authenticate_and_encrypt(connector); + if (ret) { + DRM_DEBUG_KMS("HDCP2 Type%d Enabling Failed. (%d)\n", + hdcp->content_type, ret); + return ret; + } + + DRM_DEBUG_KMS("[%s:%d] HDCP2.2 is enabled. Type %d\n", + connector->base.name, connector->base.base.id, + hdcp->content_type); + + hdcp->hdcp2_encrypted = true; + return 0; +} + +static int _intel_hdcp2_disable(struct intel_connector *connector) +{ + int ret; + + DRM_DEBUG_KMS("[%s:%d] HDCP2.2 is being Disabled\n", + connector->base.name, connector->base.base.id); + + ret = hdcp2_disable_encryption(connector); + + if (hdcp2_deauthenticate_port(connector) < 0) + DRM_DEBUG_KMS("Port deauth failed.\n"); + + connector->hdcp.hdcp2_encrypted = false; + + return ret; +} + static void intel_hdcp_check_work(struct work_struct *work) { struct intel_hdcp *hdcp = container_of(to_delayed_work(work), @@ -1263,22 +1433,34 @@ int intel_hdcp_init(struct intel_connector *connector, int intel_hdcp_enable(struct intel_connector *connector) { struct intel_hdcp *hdcp = &connector->hdcp; - int ret; + int ret = -EINVAL; if (!hdcp->shim) return -ENOENT; mutex_lock(&hdcp->mutex); + WARN_ON(hdcp->value == DRM_MODE_CONTENT_PROTECTION_ENABLED); - ret = _intel_hdcp_enable(connector); - if (ret) - goto out; + /* + * Considering that HDCP2.2 is more secure than HDCP1.4, If the setup + * is capable of HDCP2.2, it is preferred to use HDCP2.2. + */ + if (intel_hdcp2_capable(connector)) + ret = _intel_hdcp2_enable(connector); + + /* When HDCP2.2 fails, HDCP1.4 will be attempted */ + if (ret && intel_hdcp_capable(connector)) { + ret = _intel_hdcp_enable(connector); + if (!ret) + schedule_delayed_work(&hdcp->check_work, + DRM_HDCP_CHECK_PERIOD_MS); + } + + if (!ret) { + hdcp->value = DRM_MODE_CONTENT_PROTECTION_ENABLED; + schedule_work(&hdcp->prop_work); + } - hdcp->value = DRM_MODE_CONTENT_PROTECTION_ENABLED; - schedule_work(&hdcp->prop_work); - schedule_delayed_work(&hdcp->check_work, - DRM_HDCP_CHECK_PERIOD_MS); -out: mutex_unlock(&hdcp->mutex); return ret; } @@ -1295,7 +1477,9 @@ int intel_hdcp_disable(struct intel_connector *connector) if (hdcp->value != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) { hdcp->value = DRM_MODE_CONTENT_PROTECTION_UNDESIRED; - if (hdcp->hdcp_encrypted) + if (hdcp->hdcp2_encrypted) + ret = _intel_hdcp2_disable(connector); + else if (hdcp->hdcp_encrypted) ret = _intel_hdcp_disable(connector); } -- 2.30.2