[PATCH v8 06/35] drm/i915: Enable and Disable of HDCP2.2
C, Ramalingam
ramalingam.c at intel.com
Fri Dec 7 06:22:21 UTC 2018
On 12/6/2018 4:00 PM, Daniel Vetter wrote:
> On Tue, Nov 27, 2018 at 04:13:04PM +0530, Ramalingam C wrote:
>> 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.
> Patch series suggestion for next time around: First build out the helper
> functions, then time them into the big picture like here. Personally I
> think that makes it easier to understand, but it's kinda personal choice.
Tried that already. But bisecting will give warnings as "defined but
unused functions"
Hence moved to this approach.
> I guess this here works too.
>
>> 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:
>> No changes.
>> v4:
>> Extra comment added and Style issue fixed [Uma]
>> v5:
>> Rebased as part of patch reordering.
>> HDCP2 encryption status is tracked.
>> HW state check is moved into WARN_ON [Daniel]
>> v6:
>> 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]
>> v7:
>> Return values are handles [Uma]
>> Realigned the code.
>> Check for comp_master is removed.
>> v8:
>> HDCP2.2 is attempted only if mei interface is up.
>> Adjust to the new interface
>> Avoid bool usage in struct [Tomas]
>>
>> Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
>> ---
>> drivers/gpu/drm/i915/intel_drv.h | 5 +
>> drivers/gpu/drm/i915/intel_hdcp.c | 223 +++++++++++++++++++++++++++++++++++---
>> 2 files changed, 214 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
>> index bde82f3ada85..3e9f21d23442 100644
>> --- a/drivers/gpu/drm/i915/intel_drv.h
>> +++ b/drivers/gpu/drm/i915/intel_drv.h
>> @@ -383,6 +383,10 @@ struct intel_hdcp_shim {
>>
>> /* Detects the HDCP protocol(DP/HDMI) required on the port */
>> enum mei_hdcp_wired_protocol (*hdcp_protocol)(void);
>> +
>> + /* Detects whether Panel is HDCP2.2 capable */
>> + int (*hdcp_2_2_capable)(struct intel_digital_port *intel_dig_port,
>> + bool *capable);
>> };
>>
>> struct intel_hdcp {
>> @@ -396,6 +400,7 @@ struct intel_hdcp {
>> /* HDCP2.2 related definitions */
>> /* Flag indicates whether this connector supports HDCP2.2 or not. */
>> u8 hdcp2_supported;
>> + u8 hdcp2_in_use;
>>
>> /*
>> * Content Stream Type defined by content owner. TYPE0(0x0) content can
>> diff --git a/drivers/gpu/drm/i915/intel_hdcp.c b/drivers/gpu/drm/i915/intel_hdcp.c
>> index 760780f1105c..c1bd1ccd47cd 100644
>> --- a/drivers/gpu/drm/i915/intel_hdcp.c
>> +++ b/drivers/gpu/drm/i915/intel_hdcp.c
>> @@ -79,6 +79,43 @@ bool intel_hdcp_capable(struct intel_connector *connector)
>> return capable;
>> }
>>
>> +/* At present whether mei_hdcp component is binded with i915 master component */
>> +static bool intel_hdcp2_mei_binded(struct intel_connector *connector)
>> +{
>> + struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
>> + struct i915_hdcp_component_master *comp = dev_priv->hdcp_comp;
>> +
>> + mutex_lock(&comp->mutex);
>> + if (!comp->ops || !comp->dev) {
>> + mutex_unlock(&comp->mutex);
>> + return false;
>> + }
>> + mutex_unlock(&comp->mutex);
>> +
>> + return true;
>> +}
>> +
>> +/* Is HDCP2.2 capable on Platform and Sink */
>> +static bool intel_hdcp2_capable(struct intel_connector *connector)
>> +{
>> + 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 services for HDCP2.2 */
>> + if (!intel_hdcp2_mei_binded(connector))
>> + return false;
> Why do we still need this with component? Driver load should be stalled
> out until it's all there, that was kinda the entire point of component,
> so we don't have to recheck all the time whether hdcp2 is still there or
> not.
We discussed this in previous patches. Lets decide whether this approach
is good enough or not.
--Ram
>
>> +
>> + /* Sink's capability for HDCP2.2 */
>> + hdcp->shim->hdcp_2_2_capable(intel_dig_port, &capable);
>> +
>> + return capable;
>> +}
>> +
>> static int intel_hdcp_poll_ksv_fifo(struct intel_digital_port *intel_dig_port,
>> const struct intel_hdcp_shim *shim)
>> {
>> @@ -1114,8 +1151,7 @@ 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 mei_hdcp_data *data = &connector->hdcp.mei_data;
>> struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
>> @@ -1137,12 +1173,157 @@ 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,
>> + 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;
>> +
>> + 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,
>> + TIME_FOR_ENCRYPT_STATUS_CHANGE);
>> + 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_in_use = 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_in_use = false;
>> +
>> + return ret;
>> +}
>> +
>> static int i915_hdcp_component_master_bind(struct device *dev)
>> {
>> struct drm_i915_private *dev_priv = kdev_to_i915(dev);
>> @@ -1342,22 +1523,33 @@ void intel_hdcp_exit(struct drm_i915_private *dev_priv)
>> 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);
>>
>> - 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;
>> }
>> @@ -1374,7 +1566,10 @@ 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->hdcp2_in_use)
>> + ret = _intel_hdcp2_disable(connector);
>> + else
>> + ret = _intel_hdcp_disable(connector);
> Looks reasonable. So one thing we could be doing is already internally
> have a DRM_MODE_CONTENT_PROTECTION_ENABLED_TYPE1 for hdcp2.But the uapi
> would only return _ENABLED to userspace. But for internal tracking this
> would avoid the need for the separate hdcp2_in_use variable.
>
> Probably good cleanup/prep patch for the type0/1 uapi extension, once we
> get there.
>
> Aside from the component intergration question seems all reasonable. But I
> didn't yet review the hdcp2 flow, will do that once it's more complete in
> later patches.
> -Daniel
>
>> }
>>
>> mutex_unlock(&hdcp->mutex);
>> --
>> 2.7.4
>>
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