On shared (Thunderbolt) links with DP tunnels, the modeset may need to
be retried on all connectors on the link due to a link BW limitation
arising only after the atomic check phase. To support this add a helper
function queuing a work to retry the modeset on a given port's connector
and at the same time any MST connector with streams through the same
port. A follow-up change enabling the DP tunnel Bandwidth Allocation
Mode will take this into use.
v2:
- Send the uevent only to enabled MST connectors. (Jouni)
Cc: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240220211841.448846-5-imre.deak@intel.com
The system resume display mode restoration should happen with an output
configuration matching that of the suspend time saved mode. Since the
restored mode configuration is subject to the bpp fallback logic,
starting out with an unlimited bpp and reducing the bpp as required by
any (MST) link BW limit, the resulting bpp will match the one during
suspend only if the BW limit checks during suspend and resume are
applied in an identical way. The latter is not guaranteed at the moment,
since the pre-suspend MST topology may not be in place during resume
(for instance if the MST sink was disconnected while being suspended),
which makes the MST link BW check accept the unlimited bpp mode
configuration unconditionally without ensuring that the required BW fits
into the available MST link BW.
To fix the above, initialize the bpp fallback logic with the max link
bpp / force-FEC limits left behind by the suspend time mode save.
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240220211841.448846-4-imre.deak@intel.com
Add support for Display Port tunneling. For now this includes the
support for Bandwidth Allocation Mode (BWA), leaving adding Panel Replay
support for later.
BWA allows using displays that share the same (Thunderbolt) link with
their maximum resolution. Atm, this may not be possible due to the
coarse granularity of partitioning the link BW among the displays on the
link: the BW allocation policy is in a SW/FW/HW component on the link
(on Thunderbolt it's the SW or FW Connection Manager), independent of
the driver. This policy will set the DPRX maximum rate and lane count
DPCD registers the GFX driver will see (0x00000, 0x00001, 0x02200,
0x02201) based on the available link BW.
The granularity of the current BW allocation policy is coarse, based on
the required link rate in the 1.62Gbs..8.1Gbps range and it may prevent
using higher resolutions all together: the display connected first will
get a share of the link BW which corresponds to its full DPRX capability
(regardless of the actual mode it uses). A subsequent display connected
will only get the remaining BW, which could be well below its full
capability.
BWA solves the above coarse granularity (reducing it to a 250Mbs..1Gps
range) and first-come/first-served issues by letting the driver request
the BW for each display on a link which reflects the actual modes the
displays use.
This patch adds the DRM core helper functions, while a follow-up change
in the patchset takes them into use in the i915 driver.
v2:
- Fix prepare_to_wait vs. wake-up cond check order in
allocate_tunnel_bw(). (Ville)
- Move tunnel==NULL checks from callers in drivers to here. (Ville)
- Avoid var inits in declaration blocks that can fail or have
side-effects. (Ville)
- Use u8 for driver and group IDs. (Ville)
- Simplify API removing drm_dp_tunnel_get/put_untracked(). (Ville)
- Reuse str_yes_no() instead of a local yes_no_chr(). (Ville)
- s/drm_dp_tunnel_atomic_clear_state()/free_tunnel_state() and unexport
the function. (Ville)
- s/clear_tunnel_group_state()/free_group_state() and move kfree() to
this function. (Ville)
- Add separate group_free_bw() helper and describe what the tunnel
estimated BW includes. (Ville)
- Improve help text for CONFIG_DRM_DISPLAY_DP_TUNNEL. (Ville)
- Add code comment explaining the purpose of DPCD reg read helpers.
(Ville)
- Add code comment describing the tunnel group name prefix format.
(Ville)
- Report the allocated BW as undetermined until the first allocation
request.
- Skip allocation requests matching the previous request.
- Clear any stale BW request status flags before a new request.
- Add missing error return check of drm_dp_tunnel_atomic_get_group_state()
in drm_dp_tunnel_atomic_set_stream_bw().
- Add drm_dp_tunnel_get_allocated_bw().
- s/drm_dp_tunnel_atomic_get_tunnel_bw/drm_dp_tunnel_atomic_get_required_bw
- Fix return value description in function doc of drm_dp_tunnel_detect().
- Add function documentation to all exported functions.
v3:
- Improve grouping of fields in drm_dp_tunnel_group struct. (Uma)
- Fix validating the BW granularity DPCD reg value. (Uma)
- Document return value of check_and_clear_status_change(). (Uma)
- Fix resetting drm_dp_tunnel_ref::tunnel in drm_dp_tunnel_ref_put().
(Ville)
- Allow for ALLOCATED_BW to change after a BWA enable/disable sequence.
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240226185246.1276018-2-imre.deak@intel.com
Copy intel_dp_max_data_rate() to DRM core. It will be needed by a
follow-up DP tunnel patch, checking the maximum rate the DPRX (sink)
supports. Accordingly use the drm_dp_max_dprx_data_rate() name for
clarity. This patchset will also switch calling the new DRM function
in i915 instead of intel_dp_max_data_rate().
While at it simplify the function documentation/comments, removing
parts described already by drm_dp_bw_channel_coding_efficiency().
v2: (Ville)
- Remove max_link_rate_kbps.
- Simplify the function documentation.
v3:
- Rebased on latest drm-tip.
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240226185246.1276018-1-imre.deak@intel.com
Currently we are only checking capability of remote device and not
immediate downstream device but during capability check we need are
concerned with only the HDCP capability of downstream device.
During i915_display_info reporting we need HDCP Capability for both
the monitors and downstream branch device if any this patch adds that.
--v2
-Use MST Hub HDCP version [Ankit]
--v3
-Redefined how we seprate remote and direct read to make sure HDMI
shim functions are not touched [Ankit]
--v4
- Fix the conditions so that hdcp_info with remote_req true is sent
only when encoder is mst [Ankit]
--v5
-No need to have the MST Hub version in i915_hdcp_sink_capability[Ankit]
Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240223081453.1576918-9-suraj.kandpal@intel.com
Create a remote HDCP capability shim function which can read the
remote monitor HDCP capability when in MST configuration.
--v2
-Add an assertion to make sure only mst encoder call this remote_cap
function [Ankit]
--v3
-rename remote_hdcp_cap to remote_hdcp_capability [Jani]
--v4
-fix hdcp2_prerequisite check condition
-Move intel_dp_hdcp_get_remote_capability to dp_mst shim instead of
having it in dp shim [Ankit]
Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240226051017.1652970-2-suraj.kandpal@intel.com
If fixed refresh rate program the PKGC_LATENCY register
with the highest latency from level 1 and above LP registers
and program ADDED_WAKE_TIME = DSB execution time.
else program PKGC_LATENCY with all 1's and ADDED_WAKE_TIME as 0.
This is used to improve package C residency by sending the highest
latency tolerance requirement (LTR) when the planes are done with the
frame until the next frame programming window (set context latency,
window 2) starts.
Bspec: 68986
--v2
-Fix indentation [Chaitanya]
--v3
-Take into account if fixed refrersh rate or not [Vinod]
-Added wake time dependengt on DSB execution time [Vinod]
-Use REG_FIELD_PREP [Jani]
-Call program_pkgc_latency from appropriate place [Jani]
-no need for the ~0 while setting max latency [Jani]
-change commit message to add the new changes made in.
--v4
-Remove extra blank line [Vinod]
-move the vrr.enable check to previous loop [Vinod]
Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Reviewed-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240219063638.1467114-1-suraj.kandpal@intel.com
Commit 1fd4a5a36f ("drm/connector: Rename legacy TV property") failed
to update all the users of the struct drm_tv_connector_state mode field,
which resulted in a build failure in i915.
However, a subsequent commit in the same series reintroduced a mode
field in that structure, with a different semantic but the same type,
with the assumption that all previous users were updated.
Since that didn't happen, the i915 driver now compiles, but mixes
accesses to the legacy_mode field and the newer mode field, but with the
previous semantics.
This obviously doesn't work very well, so we need to update the accesses
that weren't in the legacy renaming commit.
Fixes: 1fd4a5a36f ("drm/connector: Rename legacy TV property")
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240220131251.453060-1-mripard@kernel.org
