kernel/drivers/gpu/drm/i915/display/intel_alpm.c, branch linux-rolling-stable

drm/i915/alpm: ALPM disable fixes

2026-03-19T15:15:13Z

commit eb4a7139e97374f42b7242cc754e77f1623fbcd5 upstream. PORT_ALPM_CTL is supposed to be written only before link training. Remove writing it from ALPM disable. Also clearing ALPM_CTL_ALPM_AUX_LESS_ENABLE and is not about disabling ALPM but switching to AUX-Wake ALPM. Stop touching this bit on ALPM disable. Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/7153 Fixes: 1ccbf135862b ("drm/i915/psr: Enable ALPM on source side for eDP Panel replay") Cc: Animesh Manna Cc: Jani Nikula Cc: # v6.10+ Signed-off-by: Jouni Högander Reviewed-by: Michał Grzelak Link: https://patch.msgid.link/20260212062731.397801-1-jouni.hogander@intel.com (cherry picked from commit 008304c9ae75c772d3460040de56e12112cdf5e6) Signed-off-by: Joonas Lahtinen Signed-off-by: Greg Kroah-Hartman

drm/i915/dp: Read ALPM caps after DPCD init

2026-03-19T15:14:52Z

[ Upstream commit 335b237d902c7362cb7228802e68374406b24acf ] For eDP read the ALPM DPCD caps after DPCD initalization and just before the PSR init. v2: Move intel_alpm_init to intel_edp_init_dpcd (Jouni) v3: Add Fixes with commit-id (Jouni) v4: Separated the alpm dpcd read caps from alpm_init and moved to intel_edp_init_dpcd. v5: Read alpm_caps always for eDP irrespective of the eDP version (Jouni) v6: replace drm_dp_dpcd_readb with drm_dp_dpcd_read_byte (Jouni) Fixes: 15438b325987 ("drm/i915/alpm: Add compute config for lobf") Signed-off-by: Arun R Murthy Reviewed-by: Animesh Manna Reviewed-by: Jouni Högander Signed-off-by: Animesh Manna Link: https://patch.msgid.link/20260304072157.1123283-1-arun.r.murthy@intel.com (cherry picked from commit 88442ba208dd5d3405de3f5000cf5b2c86876ae3) Signed-off-by: Tvrtko Ursulin Signed-off-by: Sasha Levin

drm/i915/alpm: Remove parameters suffix from intel_dp->alpm_parameters

2025-10-09T06:06:41Z

Now as intel_dp->alpm_parameters doesn't really contain any parameters it doesn't make sense to call it as alpm_parameters -> remove parameters suffix. Signed-off-by: Jouni Högander Reviewed-by: Animesh Manna Link: https://lore.kernel.org/r/20250929130003.28365-2-jouni.hogander@intel.com

drm/i915/alpm: Compute ALPM parameters into crtc_state->alpm_state

2025-10-09T06:06:13Z

Currently ALPM parameters are computed directly into intel_dp->alpm_parameters. This is a problem when compute config ends up to not using the computed state. Fix this by adding ALPM parameters into intel_crtc_state and compute into there. Copy needed parameters (io_wake_lines and fast_wake_lines used by PSR activate/exit) from crtc_state->alpm_state into intel_dp->alpm.alpm_parameters when they are configured into HW. v3: - enhance commit message v2: - store io/fast wake lines into intel_dp->dp instead of intel_dp->alpm_parameters and do it in intel_psr_enable_locked - rename crtc_state->alpm_parameters -> crtc_state->alpm_state - clarify commit message Signed-off-by: Jouni Högander Reviewed-by: Animesh Manna Link: https://lore.kernel.org/r/20250929130003.28365-1-jouni.hogander@intel.com

drm/i915/alpm: Remove error handling from get_lfps_cycle_min_max_time

2025-09-18T05:55:15Z

Getter for LFPS cycle min/max times is unnecessarily checking faulty port clock value. This doesn't make sense as erroneous port clock value would have been noticed already at this point. Remove this check and use 140/800 ns always when port clock > 540000. Signed-off-by: Jouni Högander Reviewed-by: Mika Kahola Link: https://lore.kernel.org/r/20250912064035.335329-1-jouni.hogander@intel.com

drm/i915/alpm: Use actual lfps cycle and silence periods in wake time

2025-09-05T05:35:47Z

Currently we are using maximum lfps cycle and silence period times when calculating AUXLess wake time. Use actual values instead. Signed-off-by: Jouni Högander Reviewed-by: Animesh Manna Link: https://lore.kernel.org/r/20250829053929.3585636-5-jouni.hogander@intel.com

drm/i915/alpm: Replace hardcoded LFPS cycle with proper calculation

2025-09-05T05:35:46Z

Currently LFPS is hadcoded for different port clocks. Replace this with proper calculation. v2: replace hardcoded 20 with 2 * LFPS_CYCLE_COUNT Signed-off-by: Jouni Högander Reviewed-by: Animesh Manna Link: https://lore.kernel.org/r/20250829053929.3585636-4-jouni.hogander@intel.com

drm/i915/alpm: Add own define for LFPS count

2025-09-05T05:35:45Z

Add own define for LFPS count and use it for the configuration. This new define will be used for calculating ALPM parameters as well. Signed-off-by: Jouni Högander Reviewed-by: Animesh Manna Link: https://lore.kernel.org/r/20250829053929.3585636-3-jouni.hogander@intel.com

drm/i915/alpm: Calculate silence period

2025-09-05T05:35:45Z

Calculate silence period instead of hardcoding it in switch case. Signed-off-by: Jouni Högander Reviewed-by: Animesh Manna Link: https://lore.kernel.org/r/20250829053929.3585636-2-jouni.hogander@intel.com

drm/i915/alpm: Move port alpm configuration

2025-05-29T05:13:42Z

It is specified in Bspec where port alpm configuration is supposed to be performed. Change accordingly. v2: - drop HAS reference - ensure PORT_ALPM registers are not writen on older platform Bspec: 68849 Signed-off-by: Jouni Högander Reviewed-by: Ankit Nautiyal Link: https://lore.kernel.org/r/20250526120512.1702815-9-jouni.hogander@intel.com