[Intel-gfx] [PATCH 1/4] drm/i915: Move execlists setup out of common

[Tvrtko Ursulin]

On 28/11/2017 12:48, Chris Wilson wrote:
> Quoting Tvrtko Ursulin (2017-11-28 12:41:27)
>> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>
>> Move the execlists specific setup out of intel_engine_setup_common. This
>> was supposed to be only for backend agnostic bits. At the same time rename
>> it to intel_engine_setup_execlist to follow the setup vs init naming
>> convetion we have.
>>
>> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>> ---
>> +static void
>> +intel_engine_setup_execlist(struct intel_engine_cs *engine)
>> +{
>> +       struct intel_engine_execlists * const execlists = &engine->execlists;
>> +
>> +       execlists->csb_use_mmio = csb_force_mmio(engine->i915);
>> +
>> +       execlists->port_mask = 1;
>> +       BUILD_BUG_ON_NOT_POWER_OF_2(execlists_num_ports(execlists));
>> +       GEM_BUG_ON(execlists_num_ports(execlists) > EXECLIST_MAX_PORTS);
>> +
>> +       execlists->queue = RB_ROOT;
>> +       execlists->first = NULL;
>> +}
> 
> The only problem here was that we wanted to be sure that some fields
> were initialised for the common paths, i.e. so we could iterate over the
> queue without worrying first if it was execlists (if it wasn't execlists
> the queue would be empty).
> 
> Now, I think we could just rely on zero initialisation, but that was the
> rationale for it ending up early. Now we could split it between
> setup_execlists and init_execlists if we want the pedantry.

Common paths as in ringbuffer submission? I grepped around and don't see 
it used there.

Then about setup vs init, we said init is for hw access so I don't 
follow how you would split the above?

Regards,

Tvrtko