[Intel-gfx] [PATCH] drm/i915/tgl: WaEnablePreemptionGranularityControlByUMD

[Tvrtko Ursulin]

On 11/03/2020 15:11, Ye, Tony wrote:
> 
> 
> On 3/10/2020 5:19 PM, Tvrtko Ursulin wrote:
>> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>
>> Certain workloads need the ability to disable preemption completely so
>> allow them to do that by whitelisting GEN8_CS_CHICKEN1.
>>
>> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>> Cc: Michal Mrozek <michal.mrozek at intel.com>
>> Cc: Tony Ye <tony.ye at intel.com>
>> Cc: Rafael Antognolli <rafael.antognolli at intel.com>
>> Cc: Jason Ekstrand <jason at jlekstrand.net>
>> ---
>> We need confirmation and acks from all three userspace components here.
>> Especially since my impression was some are for and some were against
>> whitelisting this one.
> 
> Media doesn't need this for TGL. But it's acceptable if other userspace 
> wants to whitelist it.
> 
> Acked-by: Tony Ye <tony.ye at intel.com>

Jason, Rafael - any objections?

Regards,

Tvrtko


> ---
>>   drivers/gpu/drm/i915/gt/intel_workarounds.c | 3 +++
>>   1 file changed, 3 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c 
>> b/drivers/gpu/drm/i915/gt/intel_workarounds.c
>> index 391f39b1fb26..37becdf77427 100644
>> --- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
>> +++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
>> @@ -1276,6 +1276,9 @@ static void tgl_whitelist_build(struct 
>> intel_engine_cs *engine)
>>           /* Wa_1806527549:tgl */
>>           whitelist_reg(w, HIZ_CHICKEN);
>> +
>> +        /* WaEnablePreemptionGranularityControlByUMD:tgl */
>> +        whitelist_reg(w, GEN8_CS_CHICKEN1);
>>           break;
>>       default:
>>           break;
>>