linux-kernel - RE: [PATCH v3 01/12] dt-bindings: clock: renesas,r9a08g045-vbattb: Document VBATTB

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID:
 <TY3PR01MB113460D6408A9B17DDCBFCB8586932@TY3PR01MB11346.jpnprd01.prod.outlook.com>
Date: Tue, 3 Sep 2024 07:29:29 +0000
From: Biju Das <biju.das.jz@...renesas.com>
To: Biju Das <biju.das.jz@...renesas.com>, Geert Uytterhoeven
	<geert@...ux-m68k.org>
CC: Claudiu.Beznea <claudiu.beznea@...on.dev>, "mturquette@...libre.com"
	<mturquette@...libre.com>, "sboyd@...nel.org" <sboyd@...nel.org>,
	"robh@...nel.org" <robh@...nel.org>, "krzk+dt@...nel.org"
	<krzk+dt@...nel.org>, "conor+dt@...nel.org" <conor+dt@...nel.org>,
	"alexandre.belloni@...tlin.com" <alexandre.belloni@...tlin.com>,
	"magnus.damm@...il.com" <magnus.damm@...il.com>, "p.zabel@...gutronix.de"
	<p.zabel@...gutronix.de>, "linux-renesas-soc@...r.kernel.org"
	<linux-renesas-soc@...r.kernel.org>, "linux-clk@...r.kernel.org"
	<linux-clk@...r.kernel.org>, "devicetree@...r.kernel.org"
	<devicetree@...r.kernel.org>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>, "linux-rtc@...r.kernel.org"
	<linux-rtc@...r.kernel.org>, "linux-arm-kernel@...ts.infradead.org"
	<linux-arm-kernel@...ts.infradead.org>, Claudiu Beznea
	<claudiu.beznea.uj@...renesas.com>
Subject: RE: [PATCH v3 01/12] dt-bindings: clock: renesas,r9a08g045-vbattb:
 Document VBATTB

Hi Geert,

> -----Original Message-----
> From: Biju Das <biju.das.jz@...renesas.com>
> Sent: Tuesday, September 3, 2024 8:25 AM
> Subject: RE: [PATCH v3 01/12] dt-bindings: clock: renesas,r9a08g045-vbattb: Document VBATTB
> 
> Hi Geert,
> 
> > -----Original Message-----
> > From: Geert Uytterhoeven <geert@...ux-m68k.org>
> > Sent: Tuesday, September 3, 2024 8:23 AM
> > Subject: Re: [PATCH v3 01/12] dt-bindings: clock:
> > renesas,r9a08g045-vbattb: Document VBATTB
> >
> > Hi Biju,
> >
> > On Tue, Sep 3, 2024 at 8:58 AM Biju Das <biju.das.jz@...renesas.com> wrote:
> > > > -----Original Message-----
> > > > From: Claudiu <claudiu.beznea@...on.dev>
> > > > Sent: Friday, August 30, 2024 2:02 PM
> > > > Subject: [PATCH v3 01/12] dt-bindings: clock:
> > > > renesas,r9a08g045-vbattb: Document VBATTB
> > > >
> > > > From: Claudiu Beznea <claudiu.beznea.uj@...renesas.com>
> > > >
> > > > The VBATTB IP of the Renesas RZ/G3S SoC controls the clock for
> > > > RTC, the tamper detector and a small general usage memory of 128B. Add documentation for it.
> > > >
> > > > Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@...renesas.com>
> >
> > > > --- /dev/null
> > > > +++ b/Documentation/devicetree/bindings/clock/renesas,r9a08g045-vb
> > > > +++ at
> > > > +++ tb.yaml
> > > > +  power-domains:
> > > > +    maxItems: 1
> > >
> > > Not sure, you need to document "PD_VBATT" power domain as per Table
> > > 41.2, this LSI supports 3 power domains(PD_ISOVCC, PD_VCC, PD_VBATT)
> > >
> > > Power Mode PD_ISOVCC PD_VCC PD_VBATT
> > > ALL_ON      ON          ON    ON
> > > AWO         OFF         ON    ON
> > > VBATT       OFF         OFF   ON
> > > ALL_OFF     OFF         OFF   OFF
> > >
> > > PD_VBATT domain is the area where the RTC/backup register is
> > > located, works on battery power when the power of PD_VCC and PD_ISOVCC domain are turned off.
> >
> > AFAIU, PD_VBATT cannot be controlled by the user, and is just on if main or battery power is
> supplied.

As per Figure 41.1 Power Domain and Power Supply,

If both PMIC PWS off, PD_VBATT is active, so looks like it is controllable
Outside Linux.

Cheers,
Biju