LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Marc Zyngier <maz@kernel.org>
To: Kevin Hilman <khilman@baylibre.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>,
	jbrunet@baylibre.com, linux-amlogic@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/2] irq-meson-gpio: make it possible to build as a module
Date: Mon, 26 Oct 2020 17:00:24 +0000	[thread overview]
Message-ID: <b0780e423d5fa527835ba55c64dba473@kernel.org> (raw)
In-Reply-To: <7ha6w9hsfm.fsf@baylibre.com>

On 2020-10-26 16:18, Kevin Hilman wrote:
> Marc Zyngier <maz@kernel.org> writes:
> 
>> On Tue, 20 Oct 2020 08:25:30 +0100,
>> Neil Armstrong <narmstrong@baylibre.com> wrote:
>>> 
>>> In order to reduce the kernel Image size on multi-platform 
>>> distributions,
>>> make it possible to build the Amlogic GPIO IRQ controller as a module
>>> by switching it to a platform driver.
>>> 
>>> The second patch removes MESON_IRQ_GPIO selection from ARCH_MESON to 
>>> allow
>>> building the driver as module.
>>> 
>>> Neil Armstrong (2):
>>>   irqchip: irq-meson-gpio: make it possible to build as a module
>>>   arm64: meson: remove MESON_IRQ_GPIO selection
>>> 
>>>  arch/arm64/Kconfig.platforms     |  1 -
>>>  drivers/irqchip/Kconfig          |  5 +-
>>>  drivers/irqchip/irq-meson-gpio.c | 89 
>>> ++++++++++++++++++++------------
>>>  3 files changed, 59 insertions(+), 36 deletions(-)
>> 
>> I've tried this series on my vim3l with the this driver compiled as a
>> module, and lost the Ethernet interface in the process, as the phy
>> wasn't able to resolve its interrupt and things fail later on:
>> 
>> [   72.238291] meson8b-dwmac ff3f0000.ethernet eth1: no phy at addr -1
>> [   72.238917] meson8b-dwmac ff3f0000.ethernet eth1: stmmac_open: 
>> Cannot attach to PHY (error: -19)
>> 
>> This is a generic problem with making DT-based interrupt controllers
>> modular when not *all* the drivers can deal with probing deferral.
> 
> Yes, but this series still keeps the default as built-in.
> 
> If you build as a module, and you add `fw_devlink=on` to the kernel
> command-line, device-links will be created based on DT dependencies
> which will ensure the right module load order.

It doesn't work here. I get the exact same error (well, with eth0 
instead
of eth1). In my experience, fw_devlink isn't reliable yet. Config on 
request.

> I've tested this series with `fw_devlink=on` on several Amlogic
> platforms and it works just fine, but since it requires the extra
> cmdline option, I think the default should remain built-in.
> 
> So, I'd still like to see this series merged so that at least it's an
> option to enable this as a module.

I have taken similar patches in 5.9 for other SoC families (qcomm, mtk),
and ended up reverting them in -rc2, because there is simply too much
breakage. Even keeping it as built in changes the init order, which
tons of drivers depend on. I proposed a middle-of-the-road approach
(modules can break, built-in stays the same) which Rob pushed back on.

So either we fix fw_devlink to work for everything and be on by default,
or we keep the current setup.

> Also, another reason to make it optional is that not all platforms need
> this feature at all, but right now we select it for all Amlogic SoCs.

I understand that, but I don't want another episode of widespread
breakages, and this series definitely breaks things.

Thanks,

         M.
-- 
Jazz is not dead. It just smells funny...

  reply	other threads:[~2020-10-26 17:00 UTC|newest]

Thread overview: 38+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-20  7:25 Neil Armstrong
2020-10-20  7:25 ` [PATCH 1/2] irqchip: " Neil Armstrong
2020-10-20 18:23   ` Kevin Hilman
     [not found]     ` <CAF2Aj3g6c8FEZb3e1by6sd8LpKLaeN5hsKrrQkZUvh8hosiW9A@mail.gmail.com>
2021-05-24 10:11       ` Marc Zyngier
2021-05-25 16:17         ` Kevin Hilman
2021-05-25 16:30           ` Lee Jones
2021-06-14 22:30         ` Kevin Hilman
2021-07-13  9:05           ` Lee Jones
2021-08-03  9:44           ` Marc Zyngier
2021-08-03  9:51             ` Marc Zyngier
2021-08-04  2:11               ` Saravana Kannan
2021-08-03  9:51             ` Neil Armstrong
2021-08-04  1:36             ` Saravana Kannan
2021-08-04  8:50               ` Marc Zyngier
2021-08-04 18:20                 ` Saravana Kannan
2021-08-04 21:47                   ` Saravana Kannan
2021-08-05  6:31                     ` Neil Armstrong
2021-08-06 23:55                       ` Saravana Kannan
2021-08-05  7:57                     ` Lee Jones
2021-08-16 12:47                       ` Lee Jones
2021-08-16 20:27                         ` Saravana Kannan
2021-08-16 20:46                           ` Andrew Lunn
2021-08-16 21:02                             ` Saravana Kannan
2021-08-16 21:18                               ` Andrew Lunn
2021-08-17  7:24                           ` Lee Jones
2021-08-17 18:12                             ` Saravana Kannan
2021-08-18 11:19                               ` Marc Zyngier
2021-09-02  9:28                                 ` Neil Armstrong
2020-10-20  7:25 ` [PATCH 2/2] arm64: meson: remove MESON_IRQ_GPIO selection Neil Armstrong
2020-10-20 23:18   ` Kevin Hilman
2020-10-25 11:51 ` [PATCH 0/2] irq-meson-gpio: make it possible to build as a module Marc Zyngier
2020-10-26 16:18   ` Kevin Hilman
2020-10-26 17:00     ` Marc Zyngier [this message]
2020-10-26 17:28       ` Kevin Hilman
2020-10-26 17:33         ` Kevin Hilman
2020-10-26 18:30         ` Marc Zyngier
2020-10-26 23:45       ` Kevin Hilman
2021-09-02 13:49 Neil Armstrong

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=b0780e423d5fa527835ba55c64dba473@kernel.org \
    --to=maz@kernel.org \
    --cc=jbrunet@baylibre.com \
    --cc=khilman@baylibre.com \
    --cc=linux-amlogic@lists.infradead.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=narmstrong@baylibre.com \
    --subject='Re: [PATCH 0/2] irq-meson-gpio: make it possible to build as a module' \
    /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

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).