Re: [RFC PATCH 2/2] drm/xe/uapi: Expose wmtp as engine capability

[Nirmoy Das <nirmoy.das@intel.com>]

On 7/13/2024 3:55 PM, Lucas De Marchi wrote:
> On Sat, Feb 03, 2024 at 07:05:34AM GMT, Nirmoy Das wrote:
>> Add capabilities to engine struct which can be used to
>> expose various capabilities of each engines.
>>
>> Add wmtp as engine capability which is retrieve from
>> GT info.
>>
>> Take a field from the reserved for that purpose.
>>
>> Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
>> ---
>> drivers/gpu/drm/xe/xe_query.c | 5 +++++
>> include/uapi/drm/xe_drm.h     | 6 ++++--
>> 2 files changed, 9 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/xe/xe_query.c 
>> b/drivers/gpu/drm/xe/xe_query.c
>> index 7e924faeeea0..10981b46c56f 100644
>> --- a/drivers/gpu/drm/xe/xe_query.c
>> +++ b/drivers/gpu/drm/xe/xe_query.c
>> @@ -215,6 +215,11 @@ static int query_engines(struct xe_device *xe,
>>             engines->engines[i].instance.pad = 0;
>>             memset(engines->engines[i].reserved, 0,
>>                    sizeof(engines->engines[i].reserved));
>> +            if (gt->info.has_wmtp &&
>> +                (hwe->class == XE_ENGINE_CLASS_COMPUTE ||
>> +                 hwe->class == XE_ENGINE_CLASS_RENDER))
>> +                engines->engines[i].capabilities |=
>> +                    DRM_XE_ENGINE_CAPABILITY_WMTP;
>>
>>             i++;
>>         }
>> diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
>> index 50bbea0992d9..5dac079e64de 100644
>> --- a/include/uapi/drm/xe_drm.h
>> +++ b/include/uapi/drm/xe_drm.h
>> @@ -247,9 +247,11 @@ struct drm_xe_engine_class_instance {
>> struct drm_xe_engine {
>>     /** @instance: The @drm_xe_engine_class_instance */
>>     struct drm_xe_engine_class_instance instance;
>> -
>> +#define DRM_XE_ENGINE_CAPABILITY_WMTP        BIT(0)
>> +    /** @capabilities: Capabilities of this engine. */
>> +    __u64 capabilities;
>
> isn't u64 a lot for this?  maybe make it u32 and add a u32 reserved?
>
> i915 for example reserved 64b but still only uses 2 bits.


Splitting into two u32 didn't occur to me that that time. I will do that.


Thanks,

Nirmoy

>
> Lucas De Marchi
>
>>     /** @reserved: Reserved */
>> -    __u64 reserved[3];
>> +    __u64 reserved[2];
>> };
>>
>> /**
>> -- 
>> 2.42.0
>>