Re: [Letux-kernel] [RFC PATCH 0/3] Enable 1GHz support on omap36xx

From: Adam Ford
Date: Tue Sep 10 2019 - 16:06:25 EST


On Tue, Sep 10, 2019 at 2:55 PM H. Nikolaus Schaller <hns@xxxxxxxxxxxxx> wrote:
>
> Ok,
>
> > Am 10.09.2019 um 20:51 schrieb H. Nikolaus Schaller <hns@xxxxxxxxxxxxx>:
> >
> >>>> it, but then I got some nasty errors and crashes.
> >>>
> >>> I have done the same but not (yet) seen a crash or error. Maybe you had
> >>> a typo?
> >>
> >> Can you send me an updated patch? I'd like to try to get where you
> >> are that doesn't crash.
> >
> > Yes, as soon as I have access.
>
> it turns out that my patch breaks cpufreq completely...
> So it looks as if *I* have a typo :)
>
> Hence I am likely running at constant speed and the
> VDD1 regulator is fixed a 1.200V.
>
> root@letux:~# dmesg|fgrep opp
> [ 2.426208] cpu cpu0: opp_parse_supplies: Invalid number of elements in opp-microvolt property (6) with supplies (1)
> [ 2.438140] cpu cpu0: _of_add_opp_table_v2: Failed to add OPP, -22
> root@letux:~# cat /sys/class/regulator/regulator.8/microvolts
> 1200000
> root@letux:~#
>
> The error message looks as if we have to enable multi_regulator.

That will enable both vdd and vbb regulators from what I can tell in the driver.

> And that may need to rename cpu0-supply to vdd-supply (unless the
> names can be configured).

That is consistent with what I found. vdd-supply = <&vcc>; and
vbb-supply = <&abb_mpu_iva>;
I put them both under the cpu node. Unfortunately, when I did that,
my board crashed.

I am thinking it has something to do with the abb_mpu_iva driver
because until this point, we've always operated at 800MHz or lower
which all have the same behavior in abb_mpu_iva.

With the patch you posted for the regulator, without the update to
cpufreq, and with debugging enabled, I received the following in
dmesg:

[ 1.112518] ti_abb 483072f0.regulator-abb-mpu: Missing
'efuse-address' IO resource
[ 1.112579] ti_abb 483072f0.regulator-abb-mpu: [0]v=1012500 ABB=0
ef=0x0 rbb=0x0 fbb=0x0 vset=0x0
[ 1.112609] ti_abb 483072f0.regulator-abb-mpu: [1]v=1200000 ABB=0
ef=0x0 rbb=0x0 fbb=0x0 vset=0x0
[ 1.112609] ti_abb 483072f0.regulator-abb-mpu: [2]v=1325000 ABB=0
ef=0x0 rbb=0x0 fbb=0x0 vset=0x0
[ 1.112640] ti_abb 483072f0.regulator-abb-mpu: [3]v=1375000 ABB=1
ef=0x0 rbb=0x0 fbb=0x0 vset=0x0
[ 1.112731] ti_abb 483072f0.regulator-abb-mpu: ti_abb_init_timings:
Clk_rate=13000000, sr2_cnt=0x00000032


adam
>
> BR,
> Nikolaus
>