From 86b6cf8387a4a28754fa251c79e1abfc2e57b534 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Timur=20Krist=C3=B3f?= Date: Sun, 12 Jul 2026 19:39:27 +0200 Subject: [PATCH] drm/amd/pm/si: Fix AC/DC switch notification MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit There were two mistakes in the previous implementation: The check for ATOM_PP_PLATFORM_CAP_HARDWAREDC should be inverted. We recently learned that the kernel should send PPSMC_MSG_RunningOnAC when the flag is set, and not the other way around. The clocks also need to be recomputed, because the code in the si_apply_state_adjust_rules() function selects different limits on AC and DC. Fixes: 2d071f6457af ("drm/amd/pm/si: Notify the SMC when switching to AC") Tested-by: Jeremy Klarenbeek Signed-off-by: Timur Kristóf Signed-off-by: Alex Deucher (cherry picked from commit 358dd0a9ce66d898fa934887385327547d599d88) Cc: stable@vger.kernel.org --- drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c b/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c index 9d837d23d3a7..012227c70600 100644 --- a/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c +++ b/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c @@ -3892,13 +3892,16 @@ static void si_notify_hw_of_powersource(void *handle) { struct amdgpu_device *adev = (struct amdgpu_device *)handle; - /* Check if the platform already manages the AC/DC switch via dedicated GPIO. */ - if (adev->pm.dpm.platform_caps & ATOM_PP_PLATFORM_CAP_HARDWAREDC) - return; - - /* The SMU automatically notices DC, but needs to be notified when switching to AC. */ - if (adev->pm.ac_power) + /* + * Check if the platform already manages the AC/DC switch via dedicated GPIO. + * Otherwise SMU automatically notices DC, but needs to be notified of AC. + */ + if (adev->pm.ac_power && + (adev->pm.dpm.platform_caps & ATOM_PP_PLATFORM_CAP_HARDWAREDC)) amdgpu_si_send_msg_to_smc(adev, PPSMC_MSG_RunningOnAC); + + /* Recompute clocks with updated max_limits. */ + amdgpu_legacy_dpm_compute_clocks(adev); } static PPSMC_Result si_send_msg_to_smc_with_parameter(struct amdgpu_device *adev, -- 2.47.3