[Intel-gfx] [PATCH v9 1/6] drm: Add Content protection type property
Ramalingam C
ramalingam.c at intel.com
Thu Jul 11 23:38:48 UTC 2019
On 2019-07-11 at 10:18:22 -0400, Sean Paul wrote:
> On Mon, Jul 08, 2019 at 04:51:11PM +0530, Ramalingam C wrote:
> > This patch adds a DRM ENUM property to the selected connectors.
> > This property is used for mentioning the protected content's type
> > from userspace to kernel HDCP authentication.
> >
> > Type of the stream is decided by the protected content providers.
> > Type 0 content can be rendered on any HDCP protected display wires.
> > But Type 1 content can be rendered only on HDCP2.2 protected paths.
> >
> > So when a userspace sets this property to Type 1 and starts the HDCP
> > enable, kernel will honour it only if HDCP2.2 authentication is through
> > for type 1. Else HDCP enable will be failed.
> >
> > Need ACK for this new conenctor property from userspace consumer.
> >
> > v2:
> > cp_content_type is replaced with content_protection_type [daniel]
> > check at atomic_set_property is removed [Maarten]
> > v3:
> > %s/content_protection_type/hdcp_content_type [Pekka]
> > v4:
> > property is created for the first requested connector and then reused.
> > [Danvet]
> > v5:
> > kernel doc nits addressed [Daniel]
> > Rebased as part of patch reordering.
> > v6:
> > Kernel docs are modified [pekka]
> > v7:
> > More details in Kernel docs. [pekka]
> >
> > Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
> > Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> > ---
> > drivers/gpu/drm/drm_atomic_uapi.c | 4 +++
> > drivers/gpu/drm/drm_connector.c | 39 +++++++++++++++++++++++
> > drivers/gpu/drm/drm_hdcp.c | 36 ++++++++++++++++++++-
> > drivers/gpu/drm/i915/display/intel_hdcp.c | 4 ++-
> > include/drm/drm_connector.h | 7 ++++
> > include/drm/drm_hdcp.h | 2 +-
> > include/drm/drm_mode_config.h | 6 ++++
> > include/uapi/drm/drm_mode.h | 4 +++
> > 8 files changed, 99 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
> > index abe38bdf85ae..19ae119f1a5d 100644
> > --- a/drivers/gpu/drm/drm_atomic_uapi.c
> > +++ b/drivers/gpu/drm/drm_atomic_uapi.c
> > @@ -747,6 +747,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector,
> > return -EINVAL;
> > }
> > state->content_protection = val;
> > + } else if (property == config->hdcp_content_type_property) {
> > + state->hdcp_content_type = val;
> > } else if (property == connector->colorspace_property) {
> > state->colorspace = val;
> > } else if (property == config->writeback_fb_id_property) {
> > @@ -831,6 +833,8 @@ drm_atomic_connector_get_property(struct drm_connector *connector,
> > state->hdr_output_metadata->base.id : 0;
> > } else if (property == config->content_protection_property) {
> > *val = state->content_protection;
> > + } else if (property == config->hdcp_content_type_property) {
> > + *val = state->hdcp_content_type;
> > } else if (property == config->writeback_fb_id_property) {
> > /* Writeback framebuffer is one-shot, write and forget */
> > *val = 0;
> > diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> > index 068d4b05f1be..732f6645643d 100644
> > --- a/drivers/gpu/drm/drm_connector.c
> > +++ b/drivers/gpu/drm/drm_connector.c
> > @@ -952,6 +952,45 @@ static const struct drm_prop_enum_list hdmi_colorspaces[] = {
> > * is no longer protected and userspace should take appropriate action
> > * (whatever that might be).
> > *
> > + * HDCP Content Type:
> > + * This Enum property is used by the userspace to declare the content type
> > + * of the display stream, to kernel. Here display stream stands for any
> > + * display content that userspace intended to render with HDCP encryption.
> > + *
> > + * Content Type of a stream is decided by the owner of the stream, as
> > + * "HDCP Type0" or "HDCP Type1".
> > + *
> > + * The value of the property can be one the below:
> > + * - "HDCP Type0": DRM_MODE_HDCP_CONTENT_TYPE0 = 0
> > + * - "HDCP Type1": DRM_MODE_HDCP_CONTENT_TYPE1 = 1
> > + *
> > + * When kernel starts the HDCP authentication upon the "DESIRED" state of
> > + * the "Content Protection", it refers the "HDCP Content Type" property
> > + * state. And perform the HDCP authentication with the display sink for
> > + * the content type mentioned by "HDCP Content Type".
> > + *
> > + * Stream classified as HDCP Type0 can be transmitted on a link which is
> > + * encrypted with HDCP 1.4 or higher versions of HDCP(i.e HDCP2.2
> > + * and more).
> > + *
> > + * Streams classified as HDCP Type1 can be transmitted on a link which is
> > + * encrypted only with HDCP 2.2. In future, HDCP versions >2.2 also might
> > + * support Type1 based on their spec.
> > + *
> > + * HDCP2.2 authentication protocol itself takes the "Content Type" as a
> > + * parameter, which is a input for the DP HDCP2.2 encryption algo.
> > + *
> > + * Note that the HDCP Content Type property is introduced at HDCP 2.2, and
> > + * defaults to type 0. It is only exposed by drivers supporting HDCP 2.2.
> > + * Based on how next versions of HDCP specs are defined content Type could
> > + * be used for higher versions too.
> > + *
> > + * If content type is changed when "Content Protection" is not UNDESIRED,
> > + * then kernel will disable the HDCP and re-enable with new type in the
> > + * same atomic commit. And when "Content Protection" is ENABLED, it means
> > + * that link is HDCP authenticated and encrypted, for the transmission of
> > + * the Type of stream mentioned at "HDCP Content Type".
> > + *
> > * HDR_OUTPUT_METADATA:
> > * Connector property to enable userspace to send HDR Metadata to
> > * driver. This metadata is based on the composition and blending
>
> Do we actually need an entirely new property? Can't we just add a new
> entry to the existing Content Protection property which is "Desired Type1" or
> similar? The kernel will then either attempt 2.2 auth or it will ignore it the
> request if it's not supported.
Thanks Sean for the review.
As you have mentioned earlier, "Content Protection" property is supposed
to be generic for any encryption, not just HDCP.
And content type is specific to the HDCP implementation.
And also the way content type is defined and used at HDCP2.2 spec, we
could expect when you version of spec is added to fix/improve 2.2 new
content type will be added as specific to that version.
All these points make the separate HDCP related property as more preferred.
so that only HDCP implementing driver will attach the property to the
drm connector.
Thanks,
Ram.
>
> Sean
>
> > diff --git a/drivers/gpu/drm/drm_hdcp.c b/drivers/gpu/drm/drm_hdcp.c
> > index cd837bd409f7..ce235fd1c844 100644
> > --- a/drivers/gpu/drm/drm_hdcp.c
> > +++ b/drivers/gpu/drm/drm_hdcp.c
> > @@ -344,23 +344,41 @@ static struct drm_prop_enum_list drm_cp_enum_list[] = {
> > };
> > DRM_ENUM_NAME_FN(drm_get_content_protection_name, drm_cp_enum_list)
> >
> > +static struct drm_prop_enum_list drm_hdcp_content_type_enum_list[] = {
> > + { DRM_MODE_HDCP_CONTENT_TYPE0, "HDCP Type0" },
> > + { DRM_MODE_HDCP_CONTENT_TYPE1, "HDCP Type1" },
> > +};
> > +DRM_ENUM_NAME_FN(drm_get_hdcp_content_type_name,
> > + drm_hdcp_content_type_enum_list)
> > +
> > /**
> > * drm_connector_attach_content_protection_property - attach content protection
> > * property
> > *
> > * @connector: connector to attach CP property on.
> > + * @hdcp_content_type: is HDCP Content Type property needed for connector
> > *
> > * This is used to add support for content protection on select connectors.
> > * Content Protection is intentionally vague to allow for different underlying
> > * technologies, however it is most implemented by HDCP.
> > *
> > + * When hdcp_content_type is true enum property called HDCP Content Type is
> > + * created (if it is not already) and attached to the connector.
> > + *
> > + * This property is used for sending the protected content's stream type
> > + * from userspace to kernel on selected connectors. Protected content provider
> > + * will decide their type of their content and declare the same to kernel.
> > + *
> > + * Content type will be used during the HDCP 2.2 authentication.
> > + * Content type will be set to &drm_connector_state.hdcp_content_type.
> > + *
> > * The content protection will be set to &drm_connector_state.content_protection
> > *
> > * Returns:
> > * Zero on success, negative errno on failure.
> > */
> > int drm_connector_attach_content_protection_property(
> > - struct drm_connector *connector)
> > + struct drm_connector *connector, bool hdcp_content_type)
> > {
> > struct drm_device *dev = connector->dev;
> > struct drm_property *prop =
> > @@ -377,6 +395,22 @@ int drm_connector_attach_content_protection_property(
> > DRM_MODE_CONTENT_PROTECTION_UNDESIRED);
> > dev->mode_config.content_protection_property = prop;
> >
> > + if (!hdcp_content_type)
> > + return 0;
> > +
> > + prop = dev->mode_config.hdcp_content_type_property;
> > + if (!prop)
> > + prop = drm_property_create_enum(dev, 0, "HDCP Content Type",
> > + drm_hdcp_content_type_enum_list,
> > + ARRAY_SIZE(
> > + drm_hdcp_content_type_enum_list));
> > + if (!prop)
> > + return -ENOMEM;
> > +
> > + drm_object_attach_property(&connector->base, prop,
> > + DRM_MODE_HDCP_CONTENT_TYPE0);
> > + dev->mode_config.hdcp_content_type_property = prop;
> > +
> > return 0;
> > }
> > EXPORT_SYMBOL(drm_connector_attach_content_protection_property);
> > diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
> > index bc3a94d491c4..2a4d10952b74 100644
> > --- a/drivers/gpu/drm/i915/display/intel_hdcp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
> > @@ -1829,7 +1829,9 @@ int intel_hdcp_init(struct intel_connector *connector,
> > if (!shim)
> > return -EINVAL;
> >
> > - ret = drm_connector_attach_content_protection_property(&connector->base);
> > + ret =
> > + drm_connector_attach_content_protection_property(&connector->base,
> > + false);
> > if (ret)
> > return ret;
> >
> > diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> > index 4c30d751487a..d6432967a2a9 100644
> > --- a/include/drm/drm_connector.h
> > +++ b/include/drm/drm_connector.h
> > @@ -601,6 +601,12 @@ struct drm_connector_state {
> > */
> > unsigned int content_type;
> >
> > + /**
> > + * @hdcp_content_type: Connector property to pass the type of
> > + * protected content. This is most commonly used for HDCP.
> > + */
> > + unsigned int hdcp_content_type;
> > +
> > /**
> > * @scaling_mode: Connector property to control the
> > * upscaling, mostly used for built-in panels.
> > @@ -1484,6 +1490,7 @@ const char *drm_get_dvi_i_select_name(int val);
> > const char *drm_get_tv_subconnector_name(int val);
> > const char *drm_get_tv_select_name(int val);
> > const char *drm_get_content_protection_name(int val);
> > +const char *drm_get_hdcp_content_type_name(int val);
> >
> > int drm_mode_create_dvi_i_properties(struct drm_device *dev);
> > int drm_mode_create_tv_margin_properties(struct drm_device *dev);
> > diff --git a/include/drm/drm_hdcp.h b/include/drm/drm_hdcp.h
> > index 13771a496e2b..2970abdfaf12 100644
> > --- a/include/drm/drm_hdcp.h
> > +++ b/include/drm/drm_hdcp.h
> > @@ -291,5 +291,5 @@ struct drm_connector;
> > bool drm_hdcp_check_ksvs_revoked(struct drm_device *dev,
> > u8 *ksvs, u32 ksv_count);
> > int drm_connector_attach_content_protection_property(
> > - struct drm_connector *connector);
> > + struct drm_connector *connector, bool hdcp_content_type);
> > #endif
> > diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h
> > index 759d462d028b..6c4b5bc85951 100644
> > --- a/include/drm/drm_mode_config.h
> > +++ b/include/drm/drm_mode_config.h
> > @@ -849,6 +849,12 @@ struct drm_mode_config {
> > */
> > struct drm_property *content_protection_property;
> >
> > + /**
> > + * @hdcp_content_type_property: DRM ENUM property for type of
> > + * Protected Content.
> > + */
> > + struct drm_property *hdcp_content_type_property;
> > +
> > /* dumb ioctl parameters */
> > uint32_t preferred_depth, prefer_shadow;
> >
> > diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
> > index 5ab331e5dc23..5c954394093f 100644
> > --- a/include/uapi/drm/drm_mode.h
> > +++ b/include/uapi/drm/drm_mode.h
> > @@ -218,6 +218,10 @@ extern "C" {
> > #define DRM_MODE_CONTENT_PROTECTION_DESIRED 1
> > #define DRM_MODE_CONTENT_PROTECTION_ENABLED 2
> >
> > +/* Content Type classification for HDCP2.2 vs others */
> > +#define DRM_MODE_HDCP_CONTENT_TYPE0 0
> > +#define DRM_MODE_HDCP_CONTENT_TYPE1 1
> > +
> > struct drm_mode_modeinfo {
> > __u32 clock;
> > __u16 hdisplay;
> > --
> > 2.19.1
> >
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
>
> --
> Sean Paul, Software Engineer, Google / Chromium OS
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