[igt-dev] [PATCH i-g-t 2/6] i915/i915_pm_rpm.c: create PC state subtest group

[Chris Wilson]

Quoting Anshuman Gupta (2020-12-10 05:02:48)
> On 2020-12-09 at 16:47:01 +0000, Chris Wilson wrote:
> > Quoting Anshuman Gupta (2020-12-09 16:25:02)
> > > On 2020-12-09 at 16:25:55 +0000, Chris Wilson wrote:
> > > > Quoting Anshuman Gupta (2020-12-09 16:06:38)
> > > > > Create a separate igt test group and move package C
> > > > > state in to this subgroup.
> > > > > Run powertop --auto-tune to tune SOC power configuration
> > > > > for package C state tests.
> > > > > 
> > > > > Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
> > > > > ---
> > > > >  tests/i915/i915_pm_rpm.c | 35 +++++++++++++++++++++++++++++++----
> > > > >  1 file changed, 31 insertions(+), 4 deletions(-)
> > > > > 
> > > > > diff --git a/tests/i915/i915_pm_rpm.c b/tests/i915/i915_pm_rpm.c
> > > > > index af55b569..42bc44d9 100644
> > > > > --- a/tests/i915/i915_pm_rpm.c
> > > > > +++ b/tests/i915/i915_pm_rpm.c
> > > > > @@ -832,6 +832,25 @@ static void basic_subtest(void)
> > > > >         /* XXX Also we can test wake up via exec nop */
> > > > >  }
> > > > >  
> > > > > +static bool setup_powertop(void)
> > > > > +{
> > > > > +       FILE *fp;
> > > > > +       char tmp[512];
> > > > > +
> > > > > +       fp = popen("powertop --auto-tune", "r");
> > > > 
> > > > Doesn't this defeat the point of having it work out of the box?
> May be misunderstood your comment, is it PC state or powertop should work
> out of box ?

Powermanagement should not require the user to configure it before it
can work.

powertop in particular may tweak the gfx, which is verboten.

Manually perform any configuration you think is required, and warn if the
initial configuration does not support reaching the lowest pc state the
system can. File bugs.
-Chris