On Sun, Oct 25, 2026 at 12:11 AM Atharva Tiwari
<[email protected]> wrote:
>
> From: Andre Eikmeyer <[email protected]>
>
> Plugging or unplugging the charger raises an ACPI AC event. The handler
> sent the new power source to the SMU without a runtime PM reference, so
> with GMUX keeping the GPU off every SMU message spun on skipped register
> reads for seconds. A runtime resume racing with that left the SMU
> firmware unable to start on MacBookPro15,1 and the GPU in runtime PM
> error state. Record the power source only and let the resume apply it.
>
> Signed-off-by: Atharva Tiwari <[email protected]>
> Signed-off-by: Andre Eikmeyer <[email protected]>
> ---
> drivers/gpu/drm/amd/pm/amdgpu_dpm.c | 19 +++++++++++++------
> 1 file changed, 13 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
> b/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
> index 808be6c42..b64f0b681 100644
> --- a/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
> +++ b/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
> @@ -30,6 +30,7 @@
> #include "amd_pcie.h"
> #include "amdgpu_display.h"
> #include "hwmgr.h"
> +#include <linux/pm_runtime.h>
> #include <linux/power_supply.h>
> #include "amdgpu_smu.h"
>
> @@ -498,20 +499,26 @@ int amdgpu_dpm_smu_i2c_bus_access(struct amdgpu_device
> *adev,
>
> void amdgpu_pm_acpi_event_handler(struct amdgpu_device *adev)
> {
> + int active = 0;
> +
> if (adev->pm.dpm_enabled) {
> mutex_lock(&adev->pm.mutex);
> + active = adev->pm.rpm_mode == AMDGPU_RUNPM_GMUX ?
> + pm_runtime_get_if_active(adev->dev) : 1;
There's no reason this needs to be GMUX only. You can drop the
AMDGPU_RUNPM_GMUX check here.
Alex
> +
> if (power_supply_is_system_supplied() > 0)
> adev->pm.ac_power = true;
> else
> adev->pm.ac_power = false;
>
> - if (adev->powerplay.pp_funcs &&
> - adev->powerplay.pp_funcs->notify_ac_dc)
> - amdgpu_dpm_notify_ac_dc(adev);
> -
> - if (is_support_sw_smu(adev))
> - smu_set_ac_dc(adev->powerplay.pp_handle, true);
> + if (active) {
> + if (adev->powerplay.pp_funcs &&
> + adev->powerplay.pp_funcs->notify_ac_dc)
> + amdgpu_dpm_notify_ac_dc(adev);
>
> + if (is_support_sw_smu(adev))
> + smu_set_ac_dc(adev->powerplay.pp_handle,
> true);
> + }
> mutex_unlock(&adev->pm.mutex);
> }
> }
> --
> 2.55.0
>
