[Intel-gfx] [RFC] drm/i915: Eliminate devid sprinkle

[Tvrtko Ursulin]

On 22/02/2018 08:24, Chris Wilson wrote:
> Quoting Tvrtko Ursulin (2018-02-22 08:09:07)
> 
>> diff --git a/drivers/gpu/drm/i915/intel_device_info.h b/drivers/gpu/drm/i915/intel_device_info.h
>> index 71fdfb0451ef..7b6211061fba 100644
>> --- a/drivers/gpu/drm/i915/intel_device_info.h
>> +++ b/drivers/gpu/drm/i915/intel_device_info.h
>> @@ -74,6 +74,20 @@ enum intel_platform {
>>          INTEL_MAX_PLATFORMS
>>   };
>>   
>> +/* Subplatform flags share the same namespace per parent platform. */
>> +
>> +#define INTEL_SUBPLATFORM_BITS (2)
> 
> Enough space to do the same for GT (4 bits?) on top?

Nope, only 1 bit remains with this patch. Maybe 2 if Jani lets me do 
BIT(platform - 1) for the mask. ;) You could also release your Gen1 bit. :D

Not sure if there is scope (makes sense or not) to free up some more 
bits by downgrading some of the I9[146]5GM platforms to be subplatforms 
of I9[146]G. G[M]45 also.

Or how IS_MOBILE fits in this scheme.

But anyway, not enough for gen in any case.

I think I've prototyped aggregated u64 platform+gen mask in some branch 
though. It is a small code increase overall due 64 bit immediates.

Regards,

Tvrtko