From: Tomi Valkeinen <tomi.valkeinen@ti.com>
To: Grygorii Strashko <grygorii.strashko@ti.com>,
Tony Lindgren <tony@atomide.com>
Cc: <linux-omap@vger.kernel.org>, "Andrew F . Davis" <afd@ti.com>,
Dave Gerlach <d-gerlach@ti.com>, Faiz Abbas <faiz_abbas@ti.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Keerthy <j-keerthy@ti.com>, Nishanth Menon <nm@ti.com>,
Peter Ujfalusi <peter.ujfalusi@ti.com>,
Roger Quadros <rogerq@ti.com>, Suman Anna <s-anna@ti.com>,
Tero Kristo <t-kristo@ti.com>, <linux-kernel@vger.kernel.org>,
<linux-arm-kernel@lists.infradead.org>,
<dri-devel@lists.freedesktop.org>,
Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Subject: Re: [PATCH 1/5] drm/omap: Fix suspend resume regression after platform data removal
Date: Tue, 16 Jun 2020 16:01:39 +0300 [thread overview]
Message-ID: <592501c9-2d94-b266-ae76-e383d3bffa29@ti.com> (raw)
In-Reply-To: <d03dd04f-6f2c-25ba-fe1f-d5fc0dfb5c68@ti.com>
On 11/06/2020 17:00, Grygorii Strashko wrote:
>
>
> On 09/06/2020 18:26, Tomi Valkeinen wrote:
>> On 09/06/2020 18:19, Tony Lindgren wrote:
>>>> But there's an extra runtime PM reference (dev.power.usage_count) that seems
>>>> to come out of nowhere. So when omap_drm_suspend is finished, there's still
>>>> usage_count of 1, and dispc never suspends fully.
>>>
>>> Hmm no idea about that. My guess is that there might be an issue that was
>>> masked earlier with omap_device calling the child runtime_suspend.
>>
>> Yes. It's how PM works. It calls pm_runtime_get_noresume() before starting the suspend of a
>> device. So I guess omapdrm's suspend has been broken all the time, but it was "fixed" by omap_device.
>>
>
> I think I might have an idea what is going wrong.
>
> Before:
> +----------------------+
> |omap_device_pm_domain |
> +---------------+------+------+
> | device |
> +-------------+
> | omap_device |
> +-------------+
>
> omap_device is embedded in DD device and PM handled by omap_device_pm_domain.
>
> static int _od_suspend_noirq(struct device *dev)
> {
> ...
>
> ret = pm_generic_suspend_noirq(dev);
> [1] ^^ device suspend_noirq call
>
> if (!ret && !pm_runtime_status_suspended(dev)) {
> if (pm_generic_runtime_suspend(dev) == 0) {
> [2] ^^ device pm_runtime_suspend force call
>
> omap_device_idle(pdev);
> [3] ^^ omap_device disable
> od->flags |= OMAP_DEVICE_SUSPENDED;
> }
> }
>
> return ret;
> }
>
> Now:
> +------------+
> |ti sysc dev |
> +-+----------+
> |
> |
> | +-------------+
> | | device |
> +-->+ |
> +-------------+
>
> With new approach the omap_device is not embedded in DD Device anymore,
> instead ti-sysc (hwmod replacement) became parent of DD Device.
>
> As result suspend sequence became the following
> (Note. All PM runtime PUT calls became NOP during suspend by design):
>
> device
> |-> suspend() - in case of dss omap_drm_suspend() and Co if defined
> |-> suspend_noirq() - in case of dss *not defined", equal to step [1] above
> ..
>
> ti sysc dev (ti-sysc is parent, so called after device)
> |-> sysc_noirq_suspend
> |-> pm_runtime_force_suspend()
> |-> sysc_runtime_suspend() - equal to step [3] above
>
> And step [2] is missing as of now!
>
> I think, suspend might be fixed if all devices, which are now child of ti-sysc, will do
> pm_runtime_force_xxx() calls at noirq suspend stage by adding:
>
> SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> pm_runtime_force_resume)
>
> Am I missing smth?
Isn't this almost exactly the same my patch does? I just used suspend_late and resume_early. Is
noirq phase better than late & early?
Tomi
--
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
next prev parent reply other threads:[~2020-06-16 13:02 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-31 19:39 [PATCH 0/5] Suspend and resume fixes for omapdrm pdata removal Tony Lindgren
2020-05-31 19:39 ` [PATCH 1/5] drm/omap: Fix suspend resume regression after platform data removal Tony Lindgren
2020-06-03 12:33 ` Tomi Valkeinen
2020-06-03 14:06 ` Tony Lindgren
2020-06-09 7:04 ` Tomi Valkeinen
2020-06-09 15:19 ` Tony Lindgren
2020-06-09 15:26 ` Tomi Valkeinen
2020-06-09 16:52 ` Tony Lindgren
2020-06-09 17:10 ` Tony Lindgren
2020-06-09 17:26 ` Tony Lindgren
2020-06-10 11:47 ` Tomi Valkeinen
2020-06-10 22:41 ` Tony Lindgren
2020-06-11 14:00 ` Grygorii Strashko
2020-06-11 14:32 ` Tony Lindgren
2020-06-16 13:01 ` Tomi Valkeinen [this message]
2020-06-16 15:30 ` Tony Lindgren
2020-06-16 16:56 ` Grygorii Strashko
2020-06-17 6:04 ` Tomi Valkeinen
2020-06-17 12:49 ` Grygorii Strashko
2020-05-31 19:39 ` [PATCH 2/5] bus: ti-sysc: Use optional clocks on for enable and wait for softreset bit Tony Lindgren
2020-06-01 2:19 ` kbuild test robot
2020-06-01 15:01 ` Tony Lindgren
2020-05-31 19:39 ` [PATCH 3/5] bus: ti-sysc: Ignore clockactivity unless specified as a quirk Tony Lindgren
2020-05-31 19:39 ` [PATCH 4/5] bus: ti-sysc: Fix uninitialized framedonetv_irq Tony Lindgren
2020-05-31 19:39 ` [PATCH 5/5] ARM: OMAP2+: Fix legacy mode dss_reset Tony Lindgren
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=592501c9-2d94-b266-ae76-e383d3bffa29@ti.com \
--to=tomi.valkeinen@ti.com \
--cc=afd@ti.com \
--cc=d-gerlach@ti.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=faiz_abbas@ti.com \
--cc=gregkh@linuxfoundation.org \
--cc=grygorii.strashko@ti.com \
--cc=j-keerthy@ti.com \
--cc=laurent.pinchart@ideasonboard.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-omap@vger.kernel.org \
--cc=nm@ti.com \
--cc=peter.ujfalusi@ti.com \
--cc=rogerq@ti.com \
--cc=s-anna@ti.com \
--cc=t-kristo@ti.com \
--cc=tony@atomide.com \
/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).