Re: [PATCH v2 3/3] arm64: dts: allwinner: A133: add support for Baijie Helper A133 board

From: Alexander Sverdlin

Date: Thu Jun 04 2026 - 18:43:00 EST

Hi Andre,

On Mon, 2026-05-18 at 23:54 +0200, Andre Przywara wrote:
> > > > +&reg_dcdc2 {
> > > > + regulator-always-on;
> > > > + regulator-min-microvolt = <500000>;
> > > > + regulator-max-microvolt = <1300000>; 
> > >
> > > Should be:
> > >   regulator-min-microvolt = <900000>;
> > >   regulator-max-microvolt = <1300000>; 
> >
> > 0.81..1.2v according to A133 Datasheet Revision 1.1 Jul.14, 2020?
>
> Do you have the CPU OPPs for this board? Do they slightly
> overclock/over-volt the core? We have seen this for some other boards.
> But you could go with the safer 810mV...1200mV range, and we adjust
> this when needed.

I'm not sure how to interpret this, if it helps, vendor BSP has:

root@HelperA133:~# hexdump -Cv /proc/device-tree/opp_l_table/opp@1512000000/
clock-latency-ns name opp-hz opp-microvolt-b0 opp-microvolt-b1 opp-microvolt-b2 opp-microvolt-b3
root@HelperA133:~# hexdump -Cv /proc/device-tree/opp_l_table/opp@1512000000/opp-microvolt-b0
00000000 00 12 01 60 |...`|
root@HelperA133:~# hexdump -Cv /proc/device-tree/opp_l_table/opp@1512000000/opp-microvolt-b1
00000000 00 11 3e 10 00 11 3e 10 00 11 65 20 |..>...>...e |
root@HelperA133:~# hexdump -Cv /proc/device-tree/opp_l_table/opp@1512000000/opp-microvolt-b2
00000000 00 10 c8 e0 |....|
root@HelperA133:~# hexdump -Cv /proc/device-tree/opp_l_table/opp@1512000000/opp-microvolt-b3
00000000 00 10 7a c0 |..z.|
root@HelperA133:~# hexdump -Cv /proc/device-tree/opp_l_table/compatible
00000000 61 6c 6c 77 69 6e 6e 65 72 2c 73 75 6e 35 30 69 |allwinner,sun50i|
00000010 2d 6f 70 65 72 61 74 69 6e 67 2d 70 6f 69 6e 74 |-operating-point|
00000020 73 00 |s.|

At least 1512MHz is possible (but datasheet says 1.6GHz, so probably no overclocking yet).

--
Alexander Sverdlin.