Re: [PATCH] drm/xe: Don't disable GuCRC in suspend path

["Belgaumkar, Vinay" <vinay.belgaumkar@intel.com>]

On 3/5/2026 8:56 PM, Riana Tauro wrote:
> Hi Vinay
>
> On 3/3/2026 11:44 PM, Vinay Belgaumkar wrote:
>> GuCRC should not be disabled in xe_guc_stop_prepare() as C6 is a
>> prerequisite for s0ix and s2idle. This is a regression caused by
>> the patch below.
>
> I thought since it's used in xe_uc_stop_prepare. It should've been fine.
> But I remember this issue now where gucrc shouldn't be disabled during 
> suspend.
>>
>> Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/7510
>> Fixes: 40a684f91d26 ("drm/xe: Decouple GuC RC code from xe_guc_pc")
>> Cc: Riana Tauro <riana.tauro@intel.com>
>> Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
>> ---
>>   drivers/gpu/drm/xe/xe_gt.c  | 2 ++
>>   drivers/gpu/drm/xe/xe_guc.c | 1 -
>>   2 files changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/xe/xe_gt.c b/drivers/gpu/drm/xe/xe_gt.c
>> index b455af1e6072..f3bb856aad2a 100644
>> --- a/drivers/gpu/drm/xe/xe_gt.c
>> +++ b/drivers/gpu/drm/xe/xe_gt.c
>> @@ -38,6 +38,7 @@
>>   #include "xe_gt_topology.h"
>>   #include "xe_guc_exec_queue_types.h"
>>   #include "xe_guc_pc.h"
>> +#include "xe_guc_rc.h"
>>   #include "xe_guc_submit.h"
>>   #include "xe_hw_fence.h"
>>   #include "xe_hw_engine_class_sysfs.h"
>> @@ -896,6 +897,7 @@ static void gt_reset_worker(struct work_struct *w)
>>       if (IS_SRIOV_PF(gt_to_xe(gt)))
>>           xe_gt_sriov_pf_stop_prepare(gt);
>>   +    xe_guc_rc_disable(&gt->uc.guc);
>
> Do you think we need it in gt_reset. Though i had retained it in my 
> initial patch since it was part of uc_stop
It is better to disable GuC RC during a reset since we disable SLPC as 
well. Doesn't help or hurt, but good for consistency?
>
> But i think it should be safer since we restart post gt_reset
>
> Sorry for having missed this during review. Even i didn't recall this 
> issue
>
> Reviewed-by: Riana Tauro <riana.tauro@intel.com>

Thanks,

Vinay.

>
>
>
>>       xe_uc_stop_prepare(&gt->uc);
>>       xe_pagefault_reset(gt_to_xe(gt), gt);
>>   diff --git a/drivers/gpu/drm/xe/xe_guc.c b/drivers/gpu/drm/xe/xe_guc.c
>> index 54d2fc780127..e75653a5e797 100644
>> --- a/drivers/gpu/drm/xe/xe_guc.c
>> +++ b/drivers/gpu/drm/xe/xe_guc.c
>> @@ -1671,7 +1671,6 @@ void xe_guc_stop_prepare(struct xe_guc *guc)
>>       if (!IS_SRIOV_VF(guc_to_xe(guc))) {
>>           int err;
>>   -        xe_guc_rc_disable(guc);
>>           err = xe_guc_pc_stop(&guc->pc);
>>           xe_gt_WARN(guc_to_gt(guc), err, "Failed to stop GuC PC: 
>> %pe\n",
>>                  ERR_PTR(err));
>