linux.git/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.h, branch v7.1 Linux kernel source tree drm/amd/display: Add Idle state manager(ISM) 2026-03-30T19:14:05+00:00 Ray Wu ray.wu@amd.com 2025-12-17T08:36:02+00:00 754003486c3cc95f2fcb9d6b71a779047d6db95c [Why] Rapid allow/disallow of idle optimization calls, whether it be IPS or self-refresh features, can end up using more power if actual time-in-idle is low. It can also spam DMUB command submission in a way that prevents it from servicing other requestors. [How] Introduce the Idle State Manager (ISM) to amdgpu. It maintains a finite state machine that uses a hysteresis to determine if a delay should be inserted between a caller allowing idle, and when the actual idle optimizations are programmed. A second timer is also introduced to enable static screen optimizations (SSO) such as PSR1 and Replay low HZ idle mode. Rapid SSO enable/disable can have a negative power impact on some low hz video playback, and can introduce user lag for PSR1 (due to up to 3 frames of sync latency). This effectively rate-limits idle optimizations, based on hysteresis. This also replaces the existing delay logic used for PSR1, allowing drm_vblank_crtc_config.disable_immediate = true, and thus allowing drm_crtc_vblank_restore(). v2: * Loosen criteria for ISM to exit idle optimizations; it failed to exit idle correctly on cursor updates when there are no drm_vblank requestors, * Document default_ism_config * Convert pr_debug to trace events to reduce overhead on frequent codepaths * checkpatch.pl fixes Link: https://gitlab.freedesktop.org/drm/amd/-/issues/4527 Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3709 Fixes: 58a261bfc967 ("drm/amd/display: use a more lax vblank enable policy for older ASICs") Signed-off-by: Ray Wu <ray.wu@amd.com> Signed-off-by: Leo Li <sunpeng.li@amd.com> Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[Why]

Rapid allow/disallow of idle optimization calls, whether it be IPS or
self-refresh features, can end up using more power if actual
time-in-idle is low. It can also spam DMUB command submission in a way
that prevents it from servicing other requestors.

[How]

Introduce the Idle State Manager (ISM) to amdgpu. It maintains a finite
state machine that uses a hysteresis to determine if a delay should be
inserted between a caller allowing idle, and when the actual idle
optimizations are programmed.

A second timer is also introduced to enable static screen optimizations
(SSO) such as PSR1 and Replay low HZ idle mode. Rapid SSO enable/disable
can have a negative power impact on some low hz video playback, and can
introduce user lag for PSR1 (due to up to 3 frames of sync latency).

This effectively rate-limits idle optimizations, based on hysteresis.

This also replaces the existing delay logic used for PSR1, allowing
drm_vblank_crtc_config.disable_immediate = true, and thus allowing
drm_crtc_vblank_restore().

v2:
* Loosen criteria for ISM to exit idle optimizations; it failed to exit
  idle correctly on cursor updates when there are no drm_vblank
  requestors,
* Document default_ism_config
* Convert pr_debug to trace events to reduce overhead on frequent
  codepaths
* checkpatch.pl fixes

Link: https://gitlab.freedesktop.org/drm/amd/-/issues/4527
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3709
Fixes: 58a261bfc967 ("drm/amd/display: use a more lax vblank enable policy for older ASICs")
Signed-off-by: Ray Wu <ray.wu@amd.com>
Signed-off-by: Leo Li <sunpeng.li@amd.com>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Disable replay and psr while VRR is enabled 2025-01-13T19:21:36+00:00 Tom Chung chiahsuan.chung@amd.com 2024-12-05T15:20:45+00:00 67edb81d6e9af43a0d58edf74630f82cfda4155d [Why] Replay and PSR will cause some video corruption while VRR is enabled. [How] 1. Disable the Replay and PSR while VRR is enabled. 2. Change the amdgpu_dm_crtc_vrr_active() parameter to const. Because the function will only read data from dm_crtc_state. Reviewed-by: Sun peng Li <sunpeng.li@amd.com> Signed-off-by: Tom Chung <chiahsuan.chung@amd.com> Signed-off-by: Roman Li <roman.li@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit d7879340e987b3056b8ae39db255b6c19c170a0d) Cc: stable@vger.kernel.org 
[Why]
Replay and PSR will cause some video corruption while VRR is enabled.

[How]
1. Disable the Replay and PSR while VRR is enabled.
2. Change the amdgpu_dm_crtc_vrr_active() parameter to const.
   Because the function will only read data from dm_crtc_state.

Reviewed-by: Sun peng Li <sunpeng.li@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit d7879340e987b3056b8ae39db255b6c19c170a0d)
Cc: stable@vger.kernel.org
drm/amd/display: add prefix to amdgpu_dm_crtc.h functions 2023-03-08T19:05:53+00:00 David Tadokoro davidbtadokoro@usp.br 2023-03-07T19:14:17+00:00 6c5e25a0255d56e8455869cd7f90bb9be7478132 Some amdgpu_dm_crtc.h functions didn't have names that indicated where they were declared. To better filter results in debug tools like ftrace, prefix these functions with 'amdgpu_dm_crtc_'. Signed-off-by: David Tadokoro <davidbtadokoro@usp.br> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
Some amdgpu_dm_crtc.h functions didn't have names that indicated where
they were declared.

To better filter results in debug tools like ftrace, prefix these
functions with 'amdgpu_dm_crtc_'.

Signed-off-by: David Tadokoro <davidbtadokoro@usp.br>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Create a file dedicated for CRTC 2022-07-25T13:31:01+00:00 Rodrigo Siqueira Rodrigo.Siqueira@amd.com 2022-07-20T19:43:21+00:00 473683a03495a5ed9c75a02c7497f32d6cf92c7a [Why] The amdgpu_dm file contains most of the code that works as an interface between DRM API and DC. As a result, this file becomes very large since it comprises multiple abstractions such as CRTC manipulation. [How] This commit extracts the CRTC code to its specific file named amdgpu_dm_crtc. This change does not change anything inside the functions; the only exception is converting some static functions to a global function. v2: fix ifdef merge mix up (Alex) Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Reviewed-by: Harry Wentland <Harry.Wentland@amd.com> Acked-by: Alan Liu <HaoPing.Liu@amd.com> Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[Why]
The amdgpu_dm file contains most of the code that works as an interface
between DRM API and DC. As a result, this file becomes very large since
it comprises multiple abstractions such as CRTC manipulation.

[How]
This commit extracts the CRTC code to its specific file named
amdgpu_dm_crtc. This change does not change anything inside the
functions; the only exception is converting some static functions to a
global function.

v2: fix ifdef merge mix up (Alex)

Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Acked-by: Alan Liu <HaoPing.Liu@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>