[PATCH] drm/amd/pm: correct the fan speed retrieving in PWM for some SMU13 asics

[Alex Deucher]

With Christian's comment addressed, the patch is:
Acked-by: Alex Deucher <alexander.deucher at amd.com>

On Fri, Dec 16, 2022 at 6:50 AM Christian König
<ckoenig.leichtzumerken at gmail.com> wrote:
>
> Am 16.12.22 um 11:35 schrieb Evan Quan:
> > For SMU 13.0.0 and 13.0.7, the output from PMFW is in percent. Driver
> > need to convert that into correct PMW(255) based.
> >
> > Signed-off-by: Evan Quan <evan.quan at amd.com>
> > Change-Id: I7bbeae3c0d81c6cf6e0033aa28ca6d26f5b6d178
> > ---
> >   .../gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_0_ppt.c  | 15 ++++++++++++---
> >   .../gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_7_ppt.c  | 15 ++++++++++++---
> >   2 files changed, 24 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_0_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_0_ppt.c
> > index 636cb561fea9..283cf7cf95ab 100644
> > --- a/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_0_ppt.c
> > +++ b/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_0_ppt.c
> > @@ -1445,12 +1445,21 @@ static void smu_v13_0_0_get_unique_id(struct smu_context *smu)
> >   static int smu_v13_0_0_get_fan_speed_pwm(struct smu_context *smu,
> >                                        uint32_t *speed)
> >   {
> > +     int ret = 0;
>
> Please don't initialize local variables when there isn't a need for this.
>
> We often get complains about this from automated scripts.
>
> Regards,
> Christian.
>
> > +
> >       if (!speed)
> >               return -EINVAL;
> >
> > -     return smu_v13_0_0_get_smu_metrics_data(smu,
> > -                                             METRICS_CURR_FANPWM,
> > -                                             speed);
> > +     ret = smu_v13_0_0_get_smu_metrics_data(smu,
> > +                                            METRICS_CURR_FANPWM,
> > +                                            speed);
> > +     if (ret)
> > +             return ret;
> > +
> > +     /* Convert the PMFW output which is in percent to pwm(255) based */
> > +     *speed = MIN(*speed * 255 / 100, 255);
> > +
> > +     return 0;
> >   }
> >
> >   static int smu_v13_0_0_get_fan_speed_rpm(struct smu_context *smu,
> > diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_7_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_7_ppt.c
> > index 5e937e4efb51..f207f102ed7e 100644
> > --- a/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_7_ppt.c
> > +++ b/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_7_ppt.c
> > @@ -1365,12 +1365,21 @@ static int smu_v13_0_7_populate_umd_state_clk(struct smu_context *smu)
> >   static int smu_v13_0_7_get_fan_speed_pwm(struct smu_context *smu,
> >                                        uint32_t *speed)
> >   {
> > +     int ret = 0;
> > +
> >       if (!speed)
> >               return -EINVAL;
> >
> > -     return smu_v13_0_7_get_smu_metrics_data(smu,
> > -                                             METRICS_CURR_FANPWM,
> > -                                             speed);
> > +     ret = smu_v13_0_7_get_smu_metrics_data(smu,
> > +                                            METRICS_CURR_FANPWM,
> > +                                            speed);
> > +     if (ret)
> > +             return ret;
> > +
> > +     /* Convert the PMFW output which is in percent to pwm(255) based */
> > +     *speed = MIN(*speed * 255 / 100, 255);
> > +
> > +     return 0;
> >   }
> >
> >   static int smu_v13_0_7_get_fan_speed_rpm(struct smu_context *smu,
>