[Intel-gfx] [PATCH] drm/i915/psr: Adds psrwake options for all platforms

[Pandiyan, Dhinakaran]

On Thu, 2018-06-14 at 11:59 +0530, Nagaraju, Vathsala wrote:
> 
> On 6/13/2018 11:10 PM, Dhinakaran Pandiyan wrote:
> > 
> > On Wed, 2018-06-13 at 10:32 -0700, Dhinakaran Pandiyan wrote:
> > > 
> > > On Wed, 2018-06-13 at 09:41 +0300, Jani Nikula wrote:
> > > > 
> > > > On Wed, 13 Jun 2018, "Nagaraju, Vathsala" <vathsala.nagaraju at in
> > > > tel.
> > > > co
> > > > m> wrote:
> > > > > 
> > > > > 
> > > > > On 6/12/2018 2:30 PM, Jani Nikula wrote:
> > > > > > 
> > > > > > 
> > > > > > On Tue, 12 Jun 2018, vathsala nagaraju <vathsala.nagaraju at i
> > > > > > ntel
> > > > > > .c
> > > > > > om> wrote:
> > > > > > > 
> > > > > > > 
> > > > > > > From: Vathsala Nagaraju <vathsala.nagaraju at intel.com>
> > > > > > > 
> > > > > > > Adds new psrwake options defined in the below table.
> > > > > > > Platform	PSR wake options vbt version
> > > > > > > KBL/CFL/WHL	All
> > > > > > > SKL		All PV releases (Check for 203+ might
> > > > > > > help
> > > > > > > but cannot be foolproof)
> > > > > > > BXT		Uses old interpretation.
> > > > > > > CNL/ICL+	All
> > > > > > > GLK		All
> > > > > > > 
> > > > > > > For SKL, we will continue to use older interpretation for
> > > > > > > the
> > > > > > > above reason.
> > > > > > > 
> > > > > > > Cc: Jani Nikula <jani.nikula at intel.com>
> > > > > > > Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> > > > > > > Cc: Puthikorn Voravootivat <puthik at chromium.org>
> > > > > > > Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> > > > > > > 
> > > > > > > Signed-off-by: Vathsala Nagaraju <vathsala.nagaraju at intel
> > > > > > > .com
> > > > > > > ---
> > > > > > >    drivers/gpu/drm/i915/intel_bios.c | 3 ++-
> > > > > > >    1 file changed, 2 insertions(+), 1 deletion(-)
> > > > > > > 
> > > > > > > diff --git a/drivers/gpu/drm/i915/intel_bios.c
> > > > > > > b/drivers/gpu/drm/i915/intel_bios.c
> > > > > > > index 465dff4..010ff68 100644
> > > > > > > --- a/drivers/gpu/drm/i915/intel_bios.c
> > > > > > > +++ b/drivers/gpu/drm/i915/intel_bios.c
> > > > > > > @@ -710,7 +710,8 @@ static int
> > > > > > > intel_bios_ssc_frequency(struct
> > > > > > > drm_i915_private *dev_priv,
> > > > > > >    	 * New psr options 0=500us, 1=100us, 2=2500us,
> > > > > > > 3=0us
> > > > > > >    	 * Old decimal value is wake up time in
> > > > > > > multiples
> > > > > > > of
> > > > > > > 100 us.
> > > > > > >    	 */
> > > > > > > -	if (bdb->version >= 209 && IS_GEN9_BC(dev_priv))
> > > > > > > {
> > > > > > > +	if ((INTEL_GEN(dev_priv) >= 10) ||
> > > > > > > +	    (IS_GEN9_BC(dev_priv) &&
> > > > > > > !IS_SKYLAKE(dev_priv)))
> > > > > > > {
> > > > > > Please keep the version check.
> > > > > Sure. For SKL , shall we use older interpretation for all bdb
> > > > > version as
> > > > > vbt team cannot confirm bdb version for SKL?
> > > > I guess.
> > > > 
> > > Why not change the version check to >= 203, if that's what PV
> > > releases
> > > had as per your commit message? With the current code, Linux and
> > > Windows set 500 us and 2.5 ms respectively on my laptop.
> > Said laptop is a SKL with bdb version 205.
> + ashutosh(VBT team)
> Since VBT team cannot confirm version for SKL ,so skipped for
> skylake.
> I did a copy paste of the table provided by vbt team, will edit for
> skylake.
> 
We are not going to get this right for all combinations, the best we
can do is make sure things work in most cases. I prefer to err on the
side of using the new mapping because when translated incorrectly, 3
out of 4 values lead to >= intended training time. Given the fact that
SKL PV releases also used the new mapping, I suggest you do this

if ((bdb->version >= 203 && IS_GEN9_BC(dev_priv)) ||
IS_GEMINILAKE(dev_priv) ||  INTEL_GEN(dev_priv) >= 10) {
/* new mapping */

}

I don't know what the basis for the current check for version 209 is,
other than it was the version on the KBL you tested.

-DK