linux-kernel - Re: [PATCH v2 01/11] base: power: Add generic OF-based power domain look-up

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]

Date:	Wed, 05 Mar 2014 13:44:34 +0100
From:	Tomasz Figa <tomasz.figa@...il.com>
To:	Ulf Hansson <ulf.hansson@...aro.org>
CC:	"linux-pm@...r.kernel.org" <linux-pm@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	linux-samsung-soc@...r.kernel.org,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>, devicetree@...r.kernel.org,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	"Rafael J. Wysocki" <rjw@...ysocki.net>,
	Pavel Machek <pavel@....cz>, Len Brown <len.brown@...el.com>,
	Russell King <linux@....linux.org.uk>,
	Kukjin Kim <kgene.kim@...sung.com>,
	Kumar Gala <galak@...eaurora.org>,
	Ian Campbell <ijc+devicetree@...lion.org.uk>,
	Mark Rutland <mark.rutland@....com>,
	Pawel Moll <pawel.moll@....com>,
	Rob Herring <robh+dt@...nel.org>,
	Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>,
	Stephen Warren <swarren@...dotorg.org>,
	Tomasz Figa <t.figa@...sung.com>,
	Mark Brown <broonie@...nel.org>,
	Stephen Boyd <sboyd@...eaurora.org>,
	Lorenzo Pieralisi <lorenzo.pieralisi@....com>,
	Marek Szyprowski <m.szyprowski@...sung.com>
Subject: Re: [PATCH v2 01/11] base: power: Add generic OF-based power domain
 look-up

On 05.03.2014 12:47, Tomasz Figa wrote:
> Hi Ulf,
>
> On 05.03.2014 08:19, Ulf Hansson wrote:
>>> @@ -2177,3 +2181,297 @@ void pm_genpd_init(struct generic_pm_domain
>>> *genpd,
>>>          list_add(&genpd->gpd_list_node, &gpd_list);
>>>          mutex_unlock(&gpd_list_lock);
>>>   }
>>> +
>>> +#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
>>
>> Do we need a new config for this? Can't we just use CONFIG_OF?
>>
>
> I guess we could, but initially it would have to be CONFIG_OF &&
> !CONFIG_ARCH_EXYNOS until patch 03/11 converts Exynos to use the common
> code.
>
>>> +       if (ret < 0) {
>>> +               dev_err(dev, "failed to add to power domain %s: %d",
>>> +                       pd->name, ret);
>>> +               return ret;
>>> +       }
>>> +
>>> +       pm_genpd_dev_need_restore(dev, true);
>>
>> So this will reflect the device as being inactive, which I think is
>> the wrong approach.
>>
>> Usually we should expect drivers that's being probed successfully to
>> leave their devices in active state, right?
>
> It depends on domain power state, but actually it seems to be already
> handled in __pm_genpd_add_device(), so this line might be not needed
> indeed.
>
> Strangely enough, it seemed to be needed on Exynos for correct
> operation, but maybe in the meantime some fixes in genpd code showed up.
> This will need some extra testing.

Hmm, after removing this line, power domains no longer work correctly on 
Exynos (thanks Marek for testing). Unfortunately I'm on a sick leave 
right now and I won't be able to debug this issue on Exynos for some 
time, but I'll see if I can reproduce it on s3c64xx board I have here at 
home.

Best regards,
Tomasz
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/