[Intel-gfx] [PATCH v2] drm/i915/chv: Use timeout mode for RC6 on chv

[Deepak S]

On Friday 12 December 2014 10:04 PM, Ville Syrjälä wrote:
> On Sat, Dec 13, 2014 at 11:43:27AM +0530, deepak.s at linux.intel.com wrote:
>> From: Deepak S <deepak.s at linux.intel.com>
>>
>> Higher RC6 residency is observed using timeout mode
>> instead of EI mode. It's Recommended to use TO Method for RC6.
>>
>> v2: Add comment about timeout threshold. (Tom)
> Yeah if TO is better let's just use it. The 1750us value is what
> the BIOS spec recommends, so:
>
> Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
>
>> Signed-off-by: Deepak S <deepak.s at linux.intel.com>
>> Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Why is Rodrigo's sob here?

Rodrigo had resubmitted my patch with his sob. just retained :)

>> ---
>>   drivers/gpu/drm/i915/intel_pm.c | 5 +++--
>>   1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
>> index 2316d23..2acb3de 100644
>> --- a/drivers/gpu/drm/i915/intel_pm.c
>> +++ b/drivers/gpu/drm/i915/intel_pm.c
>> @@ -4689,7 +4689,8 @@ static void cherryview_enable_rps(struct drm_device *dev)
>>   		I915_WRITE(RING_MAX_IDLE(ring->mmio_base), 10);
>>   	I915_WRITE(GEN6_RC_SLEEP, 0);
>>   
>> -	I915_WRITE(GEN6_RC6_THRESHOLD, 50000); /* 50/125ms per EI */
>> +	/* TO threshold set to 1750 us ( 0x557 * 1.28 us) */
>> +	I915_WRITE(GEN6_RC6_THRESHOLD, 0x557);
>>   
>>   	/* allows RC6 residency counter to work */
>>   	I915_WRITE(VLV_COUNTER_CONTROL,
>> @@ -4703,7 +4704,7 @@ static void cherryview_enable_rps(struct drm_device *dev)
>>   	/* 3: Enable RC6 */
>>   	if ((intel_enable_rc6(dev) & INTEL_RC6_ENABLE) &&
>>   						(pcbr >> VLV_PCBR_ADDR_SHIFT))
>> -		rc6_mode = GEN6_RC_CTL_EI_MODE(1);
>> +		rc6_mode = GEN7_RC_CTL_TO_MODE;
>>   
>>   	I915_WRITE(GEN6_RC_CONTROL, rc6_mode);
>>   
>> -- 
>> 1.9.1