From: Pavel Machek <pavel@ucw.cz>
To: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>,
"Rafael J. Wysocki" <rjw@rjwysocki.net>,
linux-kernel@vger.kernel.org,
"Rafael J. Wysocki" <rafael@kernel.org>,
Ulf Hansson <ulf.hansson@linaro.org>,
Daniel Lezcano <daniel.lezcano@linaro.org>,
linux-pm <linux-pm@vger.kernel.org>,
Thibaud Cornic <thibaud_cornic@sigmadesigns.com>,
JB <jb_lescher@sigmadesigns.com>, Mason <slash.tmp@free.fr>,
Kevin Hilman <khilman@kernel.org>,
Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: [RFC 1/2] PM / suspend: Add platform_suspend_target_state()
Date: Thu, 6 Jul 2017 05:18:19 +0200 [thread overview]
Message-ID: <20170706031819.GD12954@xo-6d-61-c0.localdomain> (raw)
In-Reply-To: <20170715183358.4bnhshokalyulswz@piout.net>
On Sat 2017-07-15 20:33:58, Alexandre Belloni wrote:
> On 15/07/2017 at 10:20:27 -0700, Florian Fainelli wrote:
> > > We already have
> > >
> > > struct regulator_state {
> > > int uV; /* suspend voltage */
> > > unsigned int mode; /* suspend regulator operating mode */
> > > int enabled; /* is regulator enabled in this suspend state */
> > > int disabled; /* is the regulator disabled in this suspend state */
> > > };
> > >
> > > * struct regulation_constraints - regulator operating constraints.
> > > * @state_disk: State for regulator when system is suspended in disk
> > > * mode.
> > > * @state_mem: State for regulator when system is suspended in mem
> > > * mode.
> > > * @state_standby: State for regulator when system is suspended in
> > > * standby
> > > * mode.
> > >
> > > . So it seems that maybe we should tell the drivers if we are entering
> > > "state_mem" or "state_standby" (something I may have opposed, sorry),
> > > then the driver can get neccessary information from regulator
> > > framework.
> >
> > OK, so what would be the mechanism to tell these drivers about the
> > system wide suspend state they are entering if it is not via
> > platform_suspend_target_state()?
> >
> > Keep in mind that regulators might be one aspect of what could be
> > causing the platform to behave specifically in one suspend state vs.
> > another, but there could be pieces of HW within the SoC that can't be
> > described with power domains, voltage islands etc. that would still have
> > inherent suspend states properties (like memory retention, pin/pad
> > controls etc. etc). We still need some mechanism, possibly centralized
> >
>
> I concur, the regulator stuff is one aspect of one of our suspend state
> (cutting VDDcore). But we have another state where the main clock (going
> to the IPs) is going from a few hundred MHz to 32kHz. This is currently
> handled by calling at91_suspend_entering_slow_clock(). I think it is
> important to take that into account so we can remove this hack from the
> kernel.
Cure should not be worse then the disease... and it is in this case.
For clocks, take a look at clock framework, perhaps it already has "clock_will_be_suspended"
as regulator framework had. If not, implement it.
Same with memory retention, pin/pad controls.
Pavel
next prev parent reply other threads:[~2017-07-16 7:34 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20170622085102.mpk7vxodpgxtrlfd@piout.net>
2017-06-23 1:08 ` [RFC 0/2] PM / suspend: Add platform_suspend_target_state() Florian Fainelli
2017-06-23 1:08 ` [RFC 1/2] " Florian Fainelli
2017-06-29 23:00 ` Rafael J. Wysocki
2017-07-12 18:08 ` Florian Fainelli
2017-07-14 22:16 ` Rafael J. Wysocki
2017-07-15 6:28 ` Pavel Machek
2017-07-15 12:17 ` Rafael J. Wysocki
2017-07-15 16:46 ` Pavel Machek
2017-07-15 17:20 ` Florian Fainelli
2017-07-15 18:33 ` Alexandre Belloni
2017-07-06 3:18 ` Pavel Machek [this message]
2017-07-16 13:41 ` Alexandre Belloni
2017-07-16 15:35 ` Florian Fainelli
2017-07-15 23:24 ` Rafael J. Wysocki
2017-07-15 23:34 ` Mason
2017-07-15 23:38 ` Rafael J. Wysocki
2017-07-16 2:36 ` Florian Fainelli
2017-07-16 10:22 ` Rafael J. Wysocki
2017-07-16 13:38 ` Alexandre Belloni
2017-07-16 18:24 ` Pavel Machek
2017-07-16 15:41 ` Florian Fainelli
2017-07-15 23:29 ` Rafael J. Wysocki
2017-07-06 3:17 ` Pavel Machek
2017-07-16 10:28 ` Rafael J. Wysocki
2017-07-16 18:22 ` Pavel Machek
2017-06-23 1:08 ` [RFC 2/2] soc: bcm: brcmstb: PM: Implement target_state callback Florian Fainelli
2017-06-29 23:04 ` Rafael J. Wysocki
2017-07-16 2:36 ` [PATCH 0/2] PM / suspend: Add platform_suspend_target_state() Florian Fainelli
2017-07-16 2:36 ` [PATCH 1/2] " Florian Fainelli
2017-07-06 3:18 ` Pavel Machek
2017-07-16 15:41 ` Florian Fainelli
2017-07-16 10:30 ` Rafael J. Wysocki
2017-07-16 2:36 ` [PATCH 2/2] soc: bcm: brcmstb: PM: Implement target_state callback Florian Fainelli
2017-07-17 20:06 ` [PATCH v2] PM / suspend: Add suspend_target_state() Florian Fainelli
2017-07-17 20:16 ` Pavel Machek
2017-07-17 21:03 ` Rafael J. Wysocki
2017-07-17 21:21 ` Florian Fainelli
2017-07-20 8:03 ` Pavel Machek
2017-07-17 22:10 ` [PATCH v3] PM / suspend: Export pm_suspend_target_state Florian Fainelli
2017-07-17 23:24 ` Rafael J. Wysocki
2017-07-18 0:19 ` [PATCH v4] " Florian Fainelli
2017-07-24 20:55 ` Rafael J. Wysocki
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20170706031819.GD12954@xo-6d-61-c0.localdomain \
--to=pavel@ucw.cz \
--cc=alexandre.belloni@free-electrons.com \
--cc=daniel.lezcano@linaro.org \
--cc=f.fainelli@gmail.com \
--cc=jb_lescher@sigmadesigns.com \
--cc=khilman@kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=rafael@kernel.org \
--cc=rjw@rjwysocki.net \
--cc=slash.tmp@free.fr \
--cc=thibaud_cornic@sigmadesigns.com \
--cc=ulf.hansson@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).