linux/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.h, branch v5.7

drm/amd/display: Add sysfs interface for set/get srm

2020-02-06T20:04:36Z

[Why] PSP doesn't have the ability to store SRM in a non-volatile memory. And since the kernel cannot write to the storage directly, we need usermode to facilitate this As per spec the SRM needs to be persistent so this interface is to be called by the usermode anytime the system goes down/powers on *boot/resume: load from storage *shutdown/suspend: save to storage [How] Provide a sysfs interface so that the usermode can set/get srm at the right times save to storage: call "cat /sys/class/drm/card0/device/hdcp_srm > file" after boot and resume -driver calls psp_get_srm() to get the stored srm and outputs it load from storage: call "cat file > /sys/class/drm/card0/device/hdcp_srm" before shutdown and suspend -driver reads the file from sysfs and calls psp_set_srm() to send the SRM to PSP v2: -update commit description -add comment about sysfs file handling in the code v3: - squash in use after free fix (Dan Carpenter) Signed-off-by: Bhawanpreet Lakha Reviewed-by: Rodrigo Siqueira Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher

drm/amd/display: Pass amdgpu_device instead of psp_context

2020-02-05T04:30:40Z

[Why] We need this to create sysfs (followup patch) [How] Change the parameter Signed-off-by: Bhawanpreet Lakha Reviewed-by: Rodrigo Siqueira Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher

drm/amd/display: add force Type0/1 flag

2019-11-19T15:12:53Z

[Why] Before we had a disable_type1 flag, this forced HDCP 2.2 to type0 There was no way to force type1. [How] Remove disable_type1 flag and instead add a flag to force type0/1. Signed-off-by: Bhawanpreet Lakha Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher

drm/amd/display: Refactor HDCP to handle multiple displays per link

2019-11-19T15:12:53Z

[Why] We need to do this to support HDCP over MST Currently we save a display per link, in a MST case we need to save multiple displays per link. [How] We can create an array per link to cache the displays, but it complicates the design. Instead we can use the module to cache the displays. Now we will always add all the displays to the module, but we use the adjustment flag to disable hdcp on all of them before they are added. When we want to enable hdcp we just query the display(cache), remove it then add it back with different adjustments. Its the similar for disable. Signed-off-by: Bhawanpreet Lakha Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher

drm/amd/display: Handle hdcp2.2 type0/1 in dm

2019-11-19T15:12:53Z

[Why] HDCP 2.2 uses type0 and type1 content type. This is passed to the receiver to stream the proper content. For example, in a MST case if the main device is HDCP2.2 capable but the secondary device is only 1.4 capabale we can use Type0 Type0 content: use HDCP 1.4 or HDCP2.2 type0 Type1 content: Only use HDCP 2.2 type1 [How] We use the "hdcp content type" property in drm. We use the disable_type1 flag in hdcp module to select the type based on the properties. For updating the property we use the same logic as 1.4, but now we consider content_type as well and update the property if the requirements are met Signed-off-by: Bhawanpreet Lakha Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher

drm/amd/display: Update CP property based on HW query

2019-10-03T14:10:58Z

[Why] We need to use HW state to set content protection to ENABLED. This way we know that the link is encrypted from the HW side [How] Create a workqueue that queries the HW every ~2seconds, and sets it to ENABLED or DESIRED based on the result from the hardware Signed-off-by: Bhawanpreet Lakha Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher

drm/amd/display: Create amdgpu_dm_hdcp

2019-10-03T14:10:58Z

[Why] We need to interact with the hdcp module from the DM, the module has to be interacted with in terms of events [How] Create the files needed for linux hdcp. These files manage the events needed for the dm to interact with the hdcp module. We use the kernel work queue to process the events needed for the module Signed-off-by: Bhawanpreet Lakha Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher