linux-kernel - Re: [PATCH 2/3] soc: c3: Add support for power domains controller

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: <20230703193736.7teaaovalia3g3ml@CAB-WSD-L081021>
Date:   Mon, 3 Jul 2023 22:37:36 +0300
From:   Dmitry Rokosov <ddrokosov@...rdevices.ru>
To:     Neil Armstrong <neil.armstrong@...aro.org>,
        =Xianwei Zhao <xianwei.zhao@...ogic.com>
CC:     <devicetree@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-amlogic@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>, Rob Herring <robh+dt@...nel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        Conor Dooley <conor+dt@...nel.org>,
        Kevin Hilman <khilman@...libre.com>
Subject: Re: [PATCH 2/3] soc: c3: Add support for power domains controller

On Mon, Jul 03, 2023 at 03:29:31PM +0200, Neil Armstrong wrote:
> Hi,
> 
> On 03/07/2023 11:31, =Xianwei Zhao wrote:
> > From: Xianwei Zhao <xianwei.zhao@...ogic.com>
> > 
> > Add support for C3 Power controller. C3 power control
> > registers are in secure domain, and should be accessed by SMC.
> > 
> > Signed-off-by: Xianwei Zhao <xianwei.zhao@...ogic.com>
> > ---
> >   drivers/soc/amlogic/meson-secure-pwrc.c | 28 ++++++++++++++++++++++++-
> >   1 file changed, 27 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/soc/amlogic/meson-secure-pwrc.c b/drivers/soc/amlogic/meson-secure-pwrc.c
> > index 25b4b71df9b8..39ccc8f2e630 100644
> > --- a/drivers/soc/amlogic/meson-secure-pwrc.c
> > +++ b/drivers/soc/amlogic/meson-secure-pwrc.c
> > @@ -12,6 +12,7 @@
> >   #include <linux/pm_domain.h>
> >   #include <dt-bindings/power/meson-a1-power.h>
> >   #include <dt-bindings/power/meson-s4-power.h>
> > +#include <dt-bindings/power/amlogic-c3-power.h>
> >   #include <linux/arm-smccc.h>
> >   #include <linux/firmware/meson/meson_sm.h>
> >   #include <linux/module.h>
> > @@ -132,6 +133,22 @@ static struct meson_secure_pwrc_domain_desc s4_pwrc_domains[] = {
> >   	SEC_PD(S4_AUDIO,	0),
> >   };
> > +static struct meson_secure_pwrc_domain_desc c3_pwrc_domains[] = {
> > +	SEC_PD(C3_NNA,	0),
> > +	SEC_PD(C3_AUDIO,	GENPD_FLAG_ALWAYS_ON),
> > +	SEC_PD(C3_SDIOA,	GENPD_FLAG_ALWAYS_ON),
> > +	SEC_PD(C3_EMMC,	GENPD_FLAG_ALWAYS_ON),
> > +	SEC_PD(C3_USB_COMB, GENPD_FLAG_ALWAYS_ON),
> > +	SEC_PD(C3_SDCARD,	GENPD_FLAG_ALWAYS_ON),
> > +	SEC_PD(C3_ETH,	GENPD_FLAG_ALWAYS_ON),
> > +	SEC_PD(C3_GE2D,	GENPD_FLAG_ALWAYS_ON),
> > +	SEC_PD(C3_CVE,	GENPD_FLAG_ALWAYS_ON),
> > +	SEC_PD(C3_GDC_WRAP,	GENPD_FLAG_ALWAYS_ON),
> > +	SEC_PD(C3_ISP_TOP,		GENPD_FLAG_ALWAYS_ON),
> > +	SEC_PD(C3_MIPI_ISP_WRAP, GENPD_FLAG_ALWAYS_ON),
> > +	SEC_PD(C3_VCODEC,	0),
> > +};
> 
> Please move this struct before _s4_
> 
> > +
> >   static int meson_secure_pwrc_probe(struct platform_device *pdev)
> >   {
> >   	int i;
> > @@ -179,7 +196,7 @@ static int meson_secure_pwrc_probe(struct platform_device *pdev)
> >   	for (i = 0 ; i < match->count ; ++i) {
> >   		struct meson_secure_pwrc_domain *dom = &pwrc->domains[i];
> > -		if (!match->domains[i].index)
> > +		if (!match->domains[i].name)
> 
> Is this change necessary ? If yes please move it to another patch
> and explain it's purpose. If it fixes something, add a Fixes tag so
> it can be backported.
> 
> Thanks,
> Neil
> 

I suppose, this change fixes the situation with SEC_PD(C3_NNA, 0)
domain, because it has index == 0.
May be it's better to introduce the separate struct member for that? For
example, 'present' (true or false).
I think code would be more readable and clean.

[...]

-- 
Thank you,
Dmitry