Commit 86b6cf8387a4 for kernel
commit 86b6cf8387a4a28754fa251c79e1abfc2e57b534
Author: Timur Kristóf <timur.kristof@gmail.com>
Date: Sun Jul 12 19:39:27 2026 +0200
drm/amd/pm/si: Fix AC/DC switch notification
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 <jeremy.klarenbeek99@gmail.com>
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 358dd0a9ce66d898fa934887385327547d599d88)
Cc: stable@vger.kernel.org
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,