[REGRESSION] drm/amd/display: Radeon 840M/860M: bisected suspend crash

[Alex Hung]

Hi,

Thanks for reporting. Can you please create a bug at 
https://gitlab.freedesktop.org/drm/amd/-/issues/ for issue tracking and 
log collection.

On 6/12/25 08:08, ggo at tuxedocomputers.com wrote:
> Hi,
> 
> I have discovered that two small form factor desktops with Ryzen AI 7
> 350 and Ryzen AI 5 340 crash when woken up from suspend. I can see how
> the LED on the USB mouse is switched on when I trigger a resume via
> keyboard button, but the display remains black. The kernel also no
> longer responds to Magic SysRq keys in this state.
> 
> The problem affects all kernels after merge b50753547453 (v6.11.0). But
> this merge only adds PCI_DEVICE_ID_AMD_1AH_M60H_ROOT with commit
> 59c34008d (necessary to trigger this bug with Ryzen AI CPU).
> I cherry-picked this commit and continued searching. Which finally led
> me to commit f6098641d3e - drm/amd/display: fix s2idle entry for DCN3.5+
> 
> If I remove the code, which has changed somewhat in the meantime, then
> the suspend works without any problems. See the following patch.
> 
> Regards,
> Georg
> 
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index d3100f641ac6..76204ae70acc 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -3121,9 +3121,6 @@ static int dm_suspend(struct amdgpu_ip_block
> *ip_block)
> 
>   	dc_set_power_state(dm->dc, DC_ACPI_CM_POWER_STATE_D3);
> 
> -	if (dm->dc->caps.ips_support && adev->in_s0ix)
> -		dc_allow_idle_optimizations(dm->dc, true);
> -
>   	dc_dmub_srv_set_power_state(dm->dc->ctx->dmub_srv,
> DC_ACPI_CM_POWER_STATE_D3);
> 
>   	return 0;
>