Linux Samsung SOC development
 help / color / mirror / Atom feed
From: Chanwoo Choi <cwchoi00@gmail.com>
To: Marek Szyprowski <m.szyprowski@samsung.com>,
	Chanwoo Choi <cw00.choi@samsung.com>,
	linux-pm@vger.kernel.org, linux-samsung-soc@vger.kernel.org
Cc: MyungJoo Ham <myungjoo.ham@samsung.com>,
	Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
	Alim Akhtar <alim.akhtar@samsung.com>
Subject: Re: [PATCH] PM / devfreq: exynos: add Exynos PPMU as a soft module dependency
Date: Mon, 29 May 2023 23:25:04 +0900	[thread overview]
Message-ID: <b2d8f6e6-689a-be77-fddf-673b08f4d993@gmail.com> (raw)
In-Reply-To: <20230518074403.2894799-1-m.szyprowski@samsung.com>

On 23. 5. 18. 16:44, Marek Szyprowski wrote:
> Commit adf8238ef403 ("ARM: dts: exynos: move exynos-bus nodes out of soc
> in Exynos4412") changed the order of the exynos-bus nodes, what results
> in different probe order of the Exynos Bus devices. Although the driver
> properly handles the deferred probe and all devices seems to be finally
> properly registered, this change revealed some kind of a bug related to
> PPMU counters registration and passive governor operation. Usually in 1
> of 10 boots this results in complete board freeze during loading of the
> kernel modules.
> 
> To avoid that freeze, ensure that the Exynos PPMU driver is already
> loaded before the Exynos Bus driver starts probing.
> 
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> ---
> This is a follow-up of the following discussion:
> https://lore.kernel.org/all/d287ca9f-b056-d39a-aa93-b0e2cb279f73@linaro.org/
> ---
>  drivers/devfreq/exynos-bus.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
> index 88414445adf3..245898f1a88e 100644
> --- a/drivers/devfreq/exynos-bus.c
> +++ b/drivers/devfreq/exynos-bus.c
> @@ -518,6 +518,7 @@ static struct platform_driver exynos_bus_platdrv = {
>  };
>  module_platform_driver(exynos_bus_platdrv);
>  
> +MODULE_SOFTDEP("pre: exynos_ppmu");
>  MODULE_DESCRIPTION("Generic Exynos Bus frequency driver");
>  MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
>  MODULE_LICENSE("GPL v2");

Applied it. Thanks.

-- 
Best Regards,
Samsung Electronics
Chanwoo Choi


      parent reply	other threads:[~2023-05-29 14:25 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <CGME20230518074416eucas1p1dfd47a3438f2252211cf7daa82e2ac1e@eucas1p1.samsung.com>
2023-05-18  7:44 ` [PATCH] PM / devfreq: exynos: add Exynos PPMU as a soft module dependency Marek Szyprowski
2023-05-18  8:09   ` Krzysztof Kozlowski
2023-05-29 14:25   ` Chanwoo Choi [this message]

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=b2d8f6e6-689a-be77-fddf-673b08f4d993@gmail.com \
    --to=cwchoi00@gmail.com \
    --cc=alim.akhtar@samsung.com \
    --cc=cw00.choi@samsung.com \
    --cc=krzysztof.kozlowski@linaro.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=linux-samsung-soc@vger.kernel.org \
    --cc=m.szyprowski@samsung.com \
    --cc=myungjoo.ham@samsung.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