Re: [PATCH] drm/i915: Correct stepping check for WaRsDisableCoarsePowerGating

From: Arun Siluvery <arun.siluvery@linux.intel.com>
To: "Ville Syrjälä" <ville.syrjala@linux.intel.com>
Cc: intel-gfx@lists.freedesktop.org
Subject: Re: [PATCH] drm/i915: Correct stepping check for WaRsDisableCoarsePowerGating
Date: Fri, 1 Apr 2016 18:09:22 +0100	[thread overview]
Message-ID: <56FEAB42.9020105@linux.intel.com> (raw)
In-Reply-To: <20160401170205.GV4329@intel.com>

On 01/04/2016 18:02, Ville Syrjälä wrote:
> On Fri, Apr 01, 2016 at 05:43:37PM +0100, Arun Siluvery wrote:
>> This WA is applied in two different places for SKL GT3, GT4 until
>> E0. Previously we were applying until F0 at one place.
>>
>> A macro was introduced in the below commit to replace both usages but now
>> we apply this WA until F0 in both places, this patch correct this.
>>
>>      commit 06e668ac91c93eb10bd21dfcc8891493722db29a
>>      Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
>>      Date:   Wed Dec 16 19:18:37 2015 +0200
>>
>>      drm/i915: Apply broader WaRsDisableCoarsePowerGating for guc also
>
> So here you're essentially reverting
> commit 344df9809f45 ("drm/i915/skl: Disable coarse power gating up until F0")
> without any justification. Why is that the right thing to do?
>
Sorry I didn't check this, I was going through some other changes and 
found it is different.

commit 344df9809f45 ("drm/i915/skl: Disable coarse power gating up until 
F0") seems pretty important which explains the difference.

This patch can be ignored.

regards
Arun

>>
>> Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
>> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
>> Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
>> ---
>>   drivers/gpu/drm/i915/i915_drv.h | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
>> index 10fc362..281f453 100644
>> --- a/drivers/gpu/drm/i915/i915_drv.h
>> +++ b/drivers/gpu/drm/i915/i915_drv.h
>> @@ -2637,7 +2637,7 @@ struct drm_i915_cmd_table {
>>   /* WaRsDisableCoarsePowerGating:skl,bxt */
>>   #define NEEDS_WaRsDisableCoarsePowerGating(dev) (IS_BXT_REVID(dev, 0, BXT_REVID_A1) || \
>>   						 ((IS_SKL_GT3(dev) || IS_SKL_GT4(dev)) && \
>> -						  IS_SKL_REVID(dev, 0, SKL_REVID_F0)))
>> +						  IS_SKL_REVID(dev, 0, SKL_REVID_E0)))
>>   /*
>>    * dp aux and gmbus irq on gen4 seems to be able to generate legacy interrupts
>>    * even when in MSI mode. This results in spurious interrupt warnings if the
>> --
>> 1.9.1
>>
>> _______________________________________________
>> Intel-gfx mailing list
>> Intel-gfx@lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
>

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx