All of lore.kernel.org
 help / color / mirror / Atom feed
From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Marc Zyngier <maz@kernel.org>
Cc: Saravana Kannan <saravanak@google.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Android Kernel Team <kernel-team@android.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Jisheng Zhang <Jisheng.Zhang@synaptics.com>,
	Kevin Hilman <khilman@baylibre.com>,
	John Stultz <john.stultz@linaro.org>,
	Nicolas Saenz Julienne <nsaenzjulienne@suse.de>,
	Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,
	Linux-Renesas <linux-renesas-soc@vger.kernel.org>
Subject: Re: [PATCH v1 5/5] driver core: Set fw_devlink=on by default
Date: Mon, 18 Jan 2021 20:16:33 +0100	[thread overview]
Message-ID: <CAMuHMdUUX22D7gV-LtDJ4jcxD=TD6soWzP=gUy4EqdFFAntoGA@mail.gmail.com> (raw)
In-Reply-To: <86db7747ea6d48eebbf40a5855240d14@kernel.org>

Hi Marc,

On Mon, Jan 18, 2021 at 6:59 PM Marc Zyngier <maz@kernel.org> wrote:
> On 2021-01-18 17:39, Geert Uytterhoeven wrote:
> > On Fri, Dec 18, 2020 at 4:34 AM Saravana Kannan <saravanak@google.com>
> > wrote:
> >> Cyclic dependencies in some firmware was one of the last remaining
> >> reasons fw_devlink=on couldn't be set by default. Now that cyclic
> >> dependencies don't block probing, set fw_devlink=on by default.
> >>
> >> Setting fw_devlink=on by default brings a bunch of benefits
> >> (currently,
> >> only for systems with device tree firmware):
> >> * Significantly cuts down deferred probes.
> >> * Device probe is effectively attempted in graph order.
> >> * Makes it much easier to load drivers as modules without having to
> >>   worry about functional dependencies between modules (depmod is still
> >>   needed for symbol dependencies).
> >>
> >> If this patch prevents some devices from probing, it's very likely due
> >> to the system having one or more device drivers that "probe"/set up a
> >> device (DT node with compatible property) without creating a struct
> >> device for it.  If we hit such cases, the device drivers need to be
> >> fixed so that they populate struct devices and probe them like normal
> >> device drivers so that the driver core is aware of the devices and
> >> their
> >> status. See [1] for an example of such a case.
> >>
> >> [1] -
> >> https://lore.kernel.org/lkml/CAGETcx9PiX==mLxB9PO8Myyk6u2vhPVwTMsA5NkD-ywH5xhusw@mail.gmail.com/
> >> Signed-off-by: Saravana Kannan <saravanak@google.com>
> >
> > Shimoda-san reported that next-20210111 and later fail to boot
> > on Renesas R-Car Gen3 platforms. No output is seen, unless earlycon
> > is enabled.
> >
> > I have bisected this to commit e590474768f1cc04 ("driver core: Set
> > fw_devlink=on by default").
>
> There is a tentative patch from Saravana here[1], which works around
> some issues on my RK3399 platform, and it'd be interesting to find
> out whether that helps on your system.
>
> Thanks,
>
>          M.
>
> [1]
> https://lore.kernel.org/r/20210116011412.3211292-1-saravanak@google.com

Thanks for the suggestion, but given no devices probe (incl. GPIO
providers), I'm afraid it won't help. [testing] Indeed.

With the debug prints in device_links_check_suppliers enabled, and
some postprocessing, I get:

    255 supplier e6180000.system-controller not ready
      9 supplier fe990000.iommu not ready
      9 supplier fe980000.iommu not ready
      6 supplier febd0000.iommu not ready
      6 supplier ec670000.iommu not ready
      3 supplier febe0000.iommu not ready
      3 supplier e7740000.iommu not ready
      3 supplier e6740000.iommu not ready
      3 supplier e65ee000.usb-phy not ready
      3 supplier e6570000.iommu not ready
      3 supplier e6054000.gpio not ready
      3 supplier e6053000.gpio not ready

As everything is part of a PM Domain, the (lack of the) system controller
must be the culprit. What's wrong with it? It is registered very early in
the boot:

[    0.142096] rcar_sysc_pd_init:442: of_genpd_add_provider_onecell() returned 0

Thanks!

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

  reply	other threads:[~2021-01-18 19:23 UTC|newest]

Thread overview: 93+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-18  3:16 [PATCH v1 0/5] Enable fw_devlink=on by default Saravana Kannan
2020-12-18  3:16 ` [PATCH v1 1/5] driver core: Add debug logs for device link related probe deferrals Saravana Kannan
2020-12-18  3:17 ` [PATCH v1 2/5] driver core: Add device link support for INFERRED flag Saravana Kannan
2020-12-18  3:17 ` [PATCH v1 3/5] driver core: Have fw_devlink use DL_FLAG_INFERRED Saravana Kannan
2020-12-18  3:17 ` [PATCH v1 4/5] driver core: Handle cycles in device links created by fw_devlink Saravana Kannan
2020-12-18  6:39   ` kernel test robot
2020-12-18  6:39     ` kernel test robot
2020-12-18  6:39   ` [RFC PATCH] driver core: fw_devlink_relax_cycle() can be static kernel test robot
2020-12-18  6:39     ` kernel test robot
2020-12-18  6:48   ` [PATCH v1 4/5] driver core: Handle cycles in device links created by fw_devlink kernel test robot
2020-12-18  6:48     ` kernel test robot
2020-12-18  7:12   ` kernel test robot
2020-12-18  7:12     ` kernel test robot
2020-12-18  3:17 ` [PATCH v1 5/5] driver core: Set fw_devlink=on by default Saravana Kannan
     [not found]   ` <CGME20210111111245eucas1p15acde7ecc2ca7f7782beb8ed74c72022@eucas1p1.samsung.com>
2021-01-11 11:12     ` Marek Szyprowski
     [not found]       ` <CGME20210111141814eucas1p1f388df07b789693a999042b27f0d8c2a@eucas1p1.samsung.com>
2021-01-11 14:18         ` Marek Szyprowski
2021-01-11 21:47           ` Saravana Kannan
2021-01-12  7:11             ` Marek Szyprowski
2021-01-12 20:51               ` Saravana Kannan
2021-01-13  7:04                 ` Marek Szyprowski
2021-01-13 19:23                   ` Saravana Kannan
2021-01-14  7:36                     ` Marek Szyprowski
2021-01-14 18:08                       ` Saravana Kannan
2021-01-18 17:43                 ` Geert Uytterhoeven
2021-01-17 23:01   ` Michael Walle
2021-01-18 21:01     ` Saravana Kannan
2021-01-19 10:41       ` Michael Walle
2021-01-20  0:00         ` Saravana Kannan
2021-01-18 17:39   ` Geert Uytterhoeven
2021-01-18 17:59     ` Marc Zyngier
2021-01-18 19:16       ` Geert Uytterhoeven [this message]
2021-01-18 19:30         ` Marc Zyngier
2021-01-18 21:18         ` Saravana Kannan
2021-01-19  9:05           ` Geert Uytterhoeven
2021-01-19 18:08             ` Saravana Kannan
2021-01-19 21:50               ` Saravana Kannan
2021-01-20  9:40                 ` Geert Uytterhoeven
2021-01-20 14:26                   ` Geert Uytterhoeven
2021-01-20 17:22                     ` Saravana Kannan
2021-01-21 16:04                       ` Geert Uytterhoeven
2021-01-25 23:30                         ` Saravana Kannan
2021-01-26  8:25                           ` Geert Uytterhoeven
2021-01-20  9:11               ` Geert Uytterhoeven
2021-01-21  8:22   ` [TEST PATCH v1] driver: core: Make fw_devlink=on more forgiving Saravana Kannan
2021-01-21  8:27     ` Saravana Kannan
2021-01-21 10:37       ` Geert Uytterhoeven
2021-01-22  1:07         ` Saravana Kannan
2021-01-21 10:33     ` Marek Szyprowski
2021-01-25 17:05   ` [PATCH v1 5/5] driver core: Set fw_devlink=on by default Tudor.Ambarus
2021-01-25 18:16     ` Saravana Kannan
2021-01-28 10:59       ` Tudor.Ambarus
2021-01-28 17:04         ` Saravana Kannan
2021-02-10  5:54   ` Guenter Roeck
2021-02-10  8:20     ` Saravana Kannan
2021-02-10 15:10       ` Guenter Roeck
2021-02-10 20:52         ` Saravana Kannan
2021-02-10 21:21           ` Guenter Roeck
2021-02-17  2:39             ` Saravana Kannan
2021-02-17  3:05               ` Guenter Roeck
2021-02-17  3:13                 ` Saravana Kannan
2020-12-18 21:11 ` [PATCH v1 0/5] Enable " Saravana Kannan
2020-12-21  8:18 ` Jisheng Zhang
     [not found]   ` <CAHp75VfqL1QuvjCZ7p23e_2qhY3DUgVNaS--Uk1mEoEHsD8GBA@mail.gmail.com>
2021-01-14 16:49     ` Saravana Kannan
2020-12-21  9:48 ` Rafael J. Wysocki
2021-01-07 20:05 ` Greg Kroah-Hartman
2021-01-07 21:53   ` Saravana Kannan
2021-01-13 11:11   ` Marc Zyngier
2021-01-13 15:27     ` Jon Hunter
2021-01-13 21:29       ` Saravana Kannan
2021-01-14 11:34         ` Jon Hunter
2021-01-14 16:40           ` Saravana Kannan
2021-01-14 16:47             ` Jon Hunter
2021-01-14 16:52               ` Saravana Kannan
2021-01-14 18:55                 ` Jon Hunter
2021-01-14 21:50                   ` Saravana Kannan
2021-01-15 16:12                     ` Jon Hunter
2021-01-15 17:44                       ` Saravana Kannan
2021-01-13 20:56     ` Saravana Kannan
2021-01-13 11:30 ` Jon Hunter
2021-01-13 21:26   ` Saravana Kannan
2021-01-14 16:11     ` Jon Hunter
2021-01-14 16:47       ` Saravana Kannan
2021-01-14 16:56         ` Jon Hunter
2021-01-28 15:03           ` Jon Hunter
2021-01-28 17:27             ` Saravana Kannan
2021-02-11  0:02             ` Saravana Kannan
2021-02-11 15:03               ` Rafael J. Wysocki
2021-02-11 17:14                 ` Saravana Kannan
2021-02-11 17:48                   ` Rafael J. Wysocki
2021-02-12  3:04                     ` Saravana Kannan
2021-01-13 11:44 ` Nicolas Saenz Julienne
2021-01-13 11:48   ` Marc Zyngier
2021-01-13 21:27     ` Saravana Kannan

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='CAMuHMdUUX22D7gV-LtDJ4jcxD=TD6soWzP=gUy4EqdFFAntoGA@mail.gmail.com' \
    --to=geert@linux-m68k.org \
    --cc=Jisheng.Zhang@synaptics.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=john.stultz@linaro.org \
    --cc=kernel-team@android.com \
    --cc=khilman@baylibre.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-renesas-soc@vger.kernel.org \
    --cc=maz@kernel.org \
    --cc=nsaenzjulienne@suse.de \
    --cc=rafael@kernel.org \
    --cc=saravanak@google.com \
    --cc=yoshihiro.shimoda.uh@renesas.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.