[Intel-gfx] [PATCH v4 2/7] drm/i915/uc: Disable GuC submission during sanitize

[Michal Wajdeczko]

On Mon, 26 Mar 2018 12:36:05 +0200, Sagar Arun Kamble  
<sagar.a.kamble at intel.com> wrote:

>
>
> On 3/23/2018 8:44 PM, Michal Wajdeczko wrote:
>> We should not leave GuC submission enabled after sanitize,
>> as we are going to reset all GuC/HuC hardware.
>>
>> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
>> Cc: Sagar Arun Kamble <sagar.a.kamble at intel.com>
>> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Either we need now destroy the doorbells cleanly or remove the below  
> comment from clients_doorbell_fini:
>          /*
>           * By the time we're here, GuC has already been reset.
>           * Instead of trying (in vain) to communicate with it, let's  
> just
>           * cleanup the doorbell HW and our internal state.
>           */

Good catch!
I'll restore symmetric doorbell cleanup in separate patch right after this  
one.

>
> One additional thing I feel we should do now is remove uc_suspend|resume  
> from gem_suspend|resume
> because we don't want to do any GuC actions once we suspend it.

Hmm, I would keep it to maintain symmetry with gem, and in us_resume we
already have guard for checking unloaded/sanitized GuC.

/m

>> ---
>>   drivers/gpu/drm/i915/intel_uc.c | 3 +++
>>   1 file changed, 3 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_uc.c  
>> b/drivers/gpu/drm/i915/intel_uc.c
>> index 34f8a2c..2389828 100644
>> --- a/drivers/gpu/drm/i915/intel_uc.c
>> +++ b/drivers/gpu/drm/i915/intel_uc.c
>> @@ -331,6 +331,9 @@ void intel_uc_sanitize(struct drm_i915_private  
>> *i915)
>>     	GEM_BUG_ON(!HAS_GUC(i915));
>>   +	if (USES_GUC_SUBMISSION(dev_priv))
>> +		intel_guc_submission_disable(guc);
>> +
>>   	guc_disable_communication(guc);
>>     	intel_huc_sanitize(huc);