[Intel-gfx] [PATCH v3 05/10] drm/i915: Prepare for multiple gts

[Tvrtko Ursulin]

On 02/11/2021 11:26, Andi Shyti wrote:
> Hi Tvrtko,
> 
>>> [...]
>>>
>>>>    static int
>>>>    intel_gt_tile_setup(struct intel_gt *gt, unsigned int id, phys_addr_t phys_addr)
>>>
>>> we don't actually need 'id', it's gt->info.id. It's introduced in
>>> patch 3 with the value '0' but it's not needed.
>>
>> I have a suspicion code got munged up over endless rebases and refactors.
>>
>> This patch is the one which introduces the id member to gt->info. But it is not setting it, even though I suspect the intent was for intel_gt_tile_setup to do that.
>>
>> Instead gt->info.id is only set to a valid value in last patch of this series inside intel_gt_probe_all:
>>
>> +		gt->i915 = i915;
>> +		gt->name = gtdef->name;
>> +		gt->type = gtdef->type;
>> +		gt->info.engine_mask = gtdef->engine_mask;
>> +		gt->info.id = i;
>> +
>> +		drm_dbg(&i915->drm, "Setting up %s %u\n", gt->name, gt->info.id);
>> +		ret = intel_gt_tile_setup(gt, i, phys_addr + gtdef->mapping_base);
>>
>> And intel_gt_tile_setup then calls __intel_gt_init_early which assigns gt->i915 yet again.
>>
>> So I'd say there is probably space to bring this all into a more streamlined flow, even more than what you suggest below.
> 
> yes, I noticed them!
> 
> Patch 3, 5 and 10 are very much connected with each other: 3
> prepares for one tile, 5 prepares for multitile and 10 does the
> multitile. While in between other patches are doing other things.
> 
> On top of some cleanups we could also rearrange the patches with
> some squashing and reordering to have them a bit more linear and
> also easier to review.

Yes. Maybe make intel_gt_tile_setup accept more arguments so it can be 
truly used to setup a gt?

   intel_gt_tile_setup(gt, id, name, type, engine_mask)

The usual thing where patch which adds something extends the prototype 
to include more stuff. If that applies here.

I know it is originally my patch but I don't have the time to rework it, 
much less the whole series, so usual dispensation to take over 
authorship if changes are large applies.

Regards,

Tvrtko