[Intel-gfx] [PATCH] drm/i915: Transform WaInPlaceDecompressionHang to a simple reg write

[Oscar Mateo]

On 09/06/2017 02:19 PM, Chris Wilson wrote:
> Quoting Oscar Mateo (2017-09-06 22:12:11)
>> Afaict, GEN9_GAMT_ECO_REG_RW_IA does not live in the context, so writing
>> it on every context creation is overkill (and wrong).
>>
>> Cc: Mika Kuoppala <mika.kuoppala at intel.com>
>> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
>> Signed-off-by: Oscar Mateo <oscar.mateo at intel.com>
>> ---
>>   drivers/gpu/drm/i915/intel_engine_cs.c | 25 +++++++++++++++----------
>>   1 file changed, 15 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
>> index 23812ec..9f01a5c 100644
>> --- a/drivers/gpu/drm/i915/intel_engine_cs.c
>> +++ b/drivers/gpu/drm/i915/intel_engine_cs.c
>> @@ -985,8 +985,9 @@ static int skl_init_workarounds(struct intel_engine_cs *engine)
>>   
>>          /* WaInPlaceDecompressionHang:skl */
>>          if (IS_SKL_REVID(dev_priv, SKL_REVID_H0, REVID_FOREVER))
>> -               WA_SET_BIT(GEN9_GAMT_ECO_REG_RW_IA,
>> -                          GAMT_ECO_ENABLE_IN_PLACE_DECOMPRESS);
> Anything using a precalculated RMW value for a ctx register is indeed
> fishy. Whilst you are checking this register, can you check whether the
> other users of WA_SET_BIT/WA_CLR_BIT are indeed context bound?
> -Chris

Sure, I'll try to go through all of them (but I'd like to clarify first 
if I should also be moving those I find to xxx_init_clock_gating).

-- Oscar