[PATCH 06/11] ARM: OMAP2+: Fix voltage scaling init for device tree

[tony@atomide.com (Tony Lindgren)]

* Joachim Eastwood <manabian@gmail.com> [140519 10:51]:
> Hi Tony,
> 
> If found this patch in your omap-for-v3.16/pm-signed tag and tested it
> on top of Linus master + omap 3.16 dt + Tomi fbdev omap. I assumed
> it's going upstream for 3.16(?).

Yes.
 
> First of all; is this safe on OMAP4460?
> As far as I understand voltage scaling on 4460 has never been
> mainline, but this code enables voltage scaling for all omap4 parts.
> More below.

Sounds like something's not right then. This should just restore
the earlier code path we had for legacy booting for omap4.

> On 11 April 2014 01:47, Tony Lindgren <tony@atomide.com> wrote:
> > We are currently disabling the init of voltage scaling
> > for device tree. With the voltage scaling problems fixed
> > for omap3 in general, there's no need to disable the voltage
> > scaling init for device tree based booting.
> >
> > Cc: Kevin Hilman <khilman@linaro.org>
> > Cc: Nishanth Menon <nm@ti.com>
> > Cc: Paul Walmsley <paul@pwsan.com>
> > Cc: Tero Kristo <t-kristo@ti.com>
> > Signed-off-by: Tony Lindgren <tony@atomide.com>
> > ---
> >  arch/arm/mach-omap2/pm.c | 28 ++++++++++++----------------
> >  1 file changed, 12 insertions(+), 16 deletions(-)
> >
> > diff --git a/arch/arm/mach-omap2/pm.c b/arch/arm/mach-omap2/pm.c
> > index e1b4141..ccefd11 100644
> > --- a/arch/arm/mach-omap2/pm.c
> > +++ b/arch/arm/mach-omap2/pm.c
> > @@ -287,25 +287,21 @@ omap_postcore_initcall(omap2_common_pm_init);
> >
> >  int __init omap2_common_pm_late_init(void)
> >  {
> > -       /*
> > -        * In the case of DT, the PMIC and SR initialization will be done using
> > -        * a completely different mechanism.
> > -        * Disable this part if a DT blob is available.
> > -        */
> > -       if (!of_have_populated_dt()) {
> > -
> > -               /* Init the voltage layer */
> > -               omap_pmic_late_init();
> > -               omap_voltage_late_init();
> > +       if (of_have_populated_dt()) {
> > +               omap3_twl_init();
> > +               omap4_twl_init();
> > +       }
> >
> > -               /* Initialize the voltages */
> > -               omap3_init_voltages();
> > -               omap4_init_voltages();
> > +       /* Init the voltage layer */
> > +       omap_pmic_late_init();
> > +       omap_voltage_late_init();
> >
> > -               /* Smartreflex device init */
> > -               omap_devinit_smartreflex();
> > +       /* Initialize the voltages */
> > +       omap3_init_voltages();
> > +       omap4_init_voltages();
> >
> > -       }
> > +       /* Smartreflex device init */
> > +       omap_devinit_smartreflex();
> >
> >         /* cpufreq dummy device instantiation */
> >         omap_init_cpufreq();
> > --
> 
> In omap4_twl_init() we have:
> if (!cpu_is_omap44xx())
>     return -ENODEV;
> 
> voltdm = voltdm_lookup("mpu");
> omap_voltage_register_pmic(voltdm, &omap4_mpu_pmic);
> 
> voltdm = voltdm_lookup("iva");
> omap_voltage_register_pmic(voltdm, &omap4_iva_pmic);
> 
> voltdm = voltdm_lookup("core");
> omap_voltage_register_pmic(voltdm, &omap4_core_pmic);
> 
> As far as I understand the setup above is only valid for 4430 and not
> 4460 since it is hook up to the twl in diffent way. External switcher
> (TPS62361) for mpu rail and the other rails are used differently.

Hmm interesting, I think we had this enabled with legacy booting?

> I also get the following messages on boot now:
> [ 2.458740] twl: not initialized
> [ 2.462127] twl6030_uv_to_vsel:OUT OF RANGE! non mapped vsel for
> 1375000 Vs max 1316660
> [ 2.470581] twl6030_uv_to_vsel:OUT OF RANGE! non mapped vsel for
> 1375000 Vs max 1316660
> [ 2.479003] twl6030_uv_to_vsel:OUT OF RANGE! non mapped vsel for
> 1375000 Vs max 1316660
> [ 2.487457] twl6030_uv_to_vsel:OUT OF RANGE! non mapped vsel for
> 1375000 Vs max 1316660
> [ 2.495880] twl6030_uv_to_vsel:OUT OF RANGE! non mapped vsel for
> 1375000 Vs max 1316660
> [ 2.504302] twl6030_uv_to_vsel:OUT OF RANGE! non mapped vsel for
> 1375000 Vs max 1316660
> [ 2.512725] twl6030_uv_to_vsel:OUT OF RANGE! non mapped vsel for
> 1410000 Vs max 1316660
> [ 2.521179] omap2_set_init_voltage: unable to find boot up OPP for vdd_mpu
> [ 2.528411] omap2_set_init_voltage: unable to set vdd_mpu
> [ 2.534088] omap2_set_init_voltage: unable to find boot up OPP for vdd_core
> [ 2.541412] omap2_set_init_voltage: unable to set vdd_core
> [ 2.547210] omap2_set_init_voltage: unable to find boot up OPP for vdd_iva
> [ 2.554443] omap2_set_init_voltage: unable to set vdd_iva
> 
> It doesn't seem too happy on my 4460.

Indeed, we need to fix it. Nishant, any comments on how we should
deal with this one?

Regards,

Tony