[Intel-gfx] [PATCH] drm/i915: Enable runtime pm

Tue Jun 16 05:23:08 PDT 2015

2015-06-16 5:34 GMT-03:00 Daniel Vetter <daniel.vetter at ffwll.ch>:
> Can I get an ack on this please? The audio folks already move ahead
>
> http://permalink.gmane.org/gmane.linux.alsa.devel/139831
>
> Would be embarassing if we are late to the party we organized ourselves ...

The situation is already embarassing for us :)

pzanoni at nhoque:~/nfs/intel-gpu-tools/tests$ sudo ./pm_rpm --quick 2>&1
| tee pm_rpm.txt
(lots of stuff)
pzanoni at nhoque:~/nfs/intel-gpu-tools/tests$ ./sumario.sh pm_rpm.txt
Subtest drm-resources-equal: FAIL (5.897s)
Subtest dpms-lpsp: FAIL (10.045s)
Subtest dpms-non-lpsp: FAIL (10.027s)
Subtest cursor-dpms: FAIL (12.693s)
Subtest legacy-planes-dpms: FAIL (12.636s)
Subtest universal-planes-dpms: FAIL (12.719s)
Subtest dpms-mode-unset-lpsp: FAIL (12.588s)
Subtest dpms-mode-unset-non-lpsp: FAIL (10.234s)
Subtest fences-dpms: FAIL (11.726s)

Total:   41
SUCCESS: 32
FAIL:    9
SKIP:    0
pzanoni at nhoque:~/nfs/intel-gpu-tools/tests$ edmesg
[  166.007957] WARNING: CPU: 1 PID: 1648 at
drivers/gpu/drm/i915/intel_uncore.c:620
hsw_unclaimed_reg_debug+0x75/0xa0 [i915]()
[  174.944917] WARNING: CPU: 1 PID: 1648 at
drivers/gpu/drm/i915/intel_uncore.c:620
hsw_unclaimed_reg_debug+0x75/0xa0 [i915]()
[  327.095531] WARNING: CPU: 0 PID: 1648 at
drivers/gpu/drm/i915/i915_gem.c:5316
i915_gem_obj_ggtt_offset_view+0xad/0x100 [i915]()
[  327.096026] WARNING: CPU: 0 PID: 1648 at
drivers/gpu/drm/i915/i915_gem.c:5316
i915_gem_obj_ggtt_offset_view+0xad/0x100 [i915]()
[  327.096597] WARNING: CPU: 0 PID: 1648 at
drivers/gpu/drm/i915/i915_gem.c:5316
i915_gem_obj_ggtt_offset_view+0xad/0x100 [i915]()
[  327.096866] WARNING: CPU: 0 PID: 1648 at
drivers/gpu/drm/i915/i915_gem.c:5316
i915_gem_obj_ggtt_offset_view+0xad/0x100 [i915]()
[  327.097089] WARNING: CPU: 0 PID: 1648 at
drivers/gpu/drm/i915/i915_gem.c:5316
i915_gem_obj_ggtt_offset_view+0xad/0x100 [i915]()
[  327.097323] WARNING: CPU: 0 PID: 1648 at
drivers/gpu/drm/i915/i915_gem.c:5316
i915_gem_obj_ggtt_offset_view+0xad/0x100 [i915]()
[  327.097534] WARNING: CPU: 0 PID: 1648 at
drivers/gpu/drm/i915/i915_gem.c:5316
i915_gem_obj_ggtt_offset_view+0xad/0x100 [i915]()
[  327.097767] WARNING: CPU: 0 PID: 1648 at
drivers/gpu/drm/i915/i915_gem.c:5316
i915_gem_obj_ggtt_offset_view+0xad/0x100 [i915]()
pzanoni at nhoque:~/nfs/intel-gpu-tools/tests$ lspci -nn | grep VGA
00:02.0 VGA compatible controller [0300]: Intel Corporation
Broadwell-U Integrated Graphics [8086:1616] (rev 09)

Please notice that, if I remember correctly, just a few weeks ago we
were passing everything, although we were having some dmesg WARNs. Now
we're not even passing the tests anymore :(

And I only see 2 pm_rpm bugs on bugzilla:
https://bugs.freedesktop.org/show_bug.cgi?id=90863
https://bugs.freedesktop.org/show_bug.cgi?id=90546

Why isn't PRTS/QA cathing stuff!?

I'm sorry, but for now, I just can't give the ACK.

> -Daniel
>
>
> On Fri, May 8, 2015 at 8:51 PM, Daniel Vetter <daniel.vetter at ffwll.ch> wrote:
>> Like with every other feature that's not enabled by default we break
>> runtime pm support way too often by accident because the overall test
>> coverage isn't great. And it's been almost 2 years since we enabled
>> the power well code by default
>>
>> commit bf51d5e2cda5d36d98e4b46ac7fca9461e512c41
>> Author: Paulo Zanoni <paulo.r.zanoni at intel.com>
>> Date:   Wed Jul 3 17:12:13 2013 -0300
>>
>>     drm/i915: switch disable_power_well default value to 1
>>
>> It's really more than overdue for runtime pm itself to follow!
>>
>> Note that in practice this wont do a hole lot yet, since we're still
>> gated on snd-hda-intel doing proper runtime pm. But I've discussed
>> this with Liam and we agreed that this needs to be done. And the audio
>> team is working to hold up their end of this bargain.
>>
>> And the justification for updating the autosuspend delay to 100ms:
>> Quick measurment shows that we can do a full rpm cycle in about 5ms,
>> which means the delay should still be really conservative from a power
>> conservation pov. The only workload that would suffer from ping-pong
>> is also only gpu/compute with all screens off. 100ms should cover any
>> kind of latency with submitting follow-up batches.
>>
>> Cc: Takashi Iwai <tiwai at suse.de>
>> Cc: Liam Girdwood <liam.r.girdwood at intel.com>
>> Cc: Yang, Libin <libin.yang at intel.com>
>> Cc: Lin, Mengdong <mengdong.lin at intel.com>
>> Cc: Li, Jocelyn <jocelyn.li at intel.com>
>> Cc: Kaskinen, Tanu <tanu.kaskinen at intel.com>
>> Cc: Zanoni, Paulo R <paulo.r.zanoni at intel.com>
>> Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
>> ---
>>  drivers/gpu/drm/i915/intel_runtime_pm.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
>> index 317b9b43d1c1..36ecbe275dd9 100644
>> --- a/drivers/gpu/drm/i915/intel_runtime_pm.c
>> +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
>> @@ -1919,9 +1919,10 @@ void intel_runtime_pm_enable(struct drm_i915_private *dev_priv)
>>                 return;
>>         }
>>
>> -       pm_runtime_set_autosuspend_delay(device, 10000); /* 10s */
>> +       pm_runtime_set_autosuspend_delay(device, 100);
>>         pm_runtime_mark_last_busy(device);
>>         pm_runtime_use_autosuspend(device);
>> +       pm_runtime_allow(device);
>>
>>         pm_runtime_put_autosuspend(device);
>>  }
>> --
>> 2.1.0
>>
>
>
>
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> +41 (0) 79 365 57 48 - http://blog.ffwll.ch
> _______________________________________________
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> Intel-gfx at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Paulo Zanoni