All of lore.kernel.org
 help / color / mirror / Atom feed
From: Tony Lindgren <tony@atomide.com>
To: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Paul Walmsley <paul@pwsan.com>,
	Rajendra Nayak <rnayak@codeaurora.org>,
	Will Deacon <will.deacon@arm.com>, Tero Kristo <t-kristo@ti.com>,
	linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] ARM: avoid Cortex-A9 livelock on tight dmb loops
Date: Tue, 10 Apr 2018 06:41:49 -0700	[thread overview]
Message-ID: <20180410134149.GQ5700@atomide.com> (raw)
In-Reply-To: <E1f5qij-00033R-Sl@rmk-PC.armlinux.org.uk>

* Russell King <rmk+kernel@armlinux.org.uk> [180410 10:43]:
> diff --git a/arch/arm/mach-omap2/prm_common.c b/arch/arm/mach-omap2/prm_common.c
> index 021b5a8b9c0a..d4ddc78b2a0b 100644
> --- a/arch/arm/mach-omap2/prm_common.c
> +++ b/arch/arm/mach-omap2/prm_common.c
> @@ -523,7 +523,7 @@ void omap_prm_reset_system(void)
>  	prm_ll_data->reset_system();
>  
>  	while (1)
> -		cpu_relax();
> +		cpu_do_idle();
>  }
>  

Hmm we need to check so the added WFI here does not cause an
undesired change to a low power state. Adding Tero to Cc also.

Regards,

Tony

WARNING: multiple messages have this Message-ID (diff)
From: tony@atomide.com (Tony Lindgren)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] ARM: avoid Cortex-A9 livelock on tight dmb loops
Date: Tue, 10 Apr 2018 06:41:49 -0700	[thread overview]
Message-ID: <20180410134149.GQ5700@atomide.com> (raw)
In-Reply-To: <E1f5qij-00033R-Sl@rmk-PC.armlinux.org.uk>

* Russell King <rmk+kernel@armlinux.org.uk> [180410 10:43]:
> diff --git a/arch/arm/mach-omap2/prm_common.c b/arch/arm/mach-omap2/prm_common.c
> index 021b5a8b9c0a..d4ddc78b2a0b 100644
> --- a/arch/arm/mach-omap2/prm_common.c
> +++ b/arch/arm/mach-omap2/prm_common.c
> @@ -523,7 +523,7 @@ void omap_prm_reset_system(void)
>  	prm_ll_data->reset_system();
>  
>  	while (1)
> -		cpu_relax();
> +		cpu_do_idle();
>  }
>  

Hmm we need to check so the added WFI here does not cause an
undesired change to a low power state. Adding Tero to Cc also.

Regards,

Tony

  reply	other threads:[~2018-04-10 13:41 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-10 10:41 [PATCH] ARM: avoid Cortex-A9 livelock on tight dmb loops Russell King
2018-04-10 10:41 ` Russell King
2018-04-10 13:41 ` Tony Lindgren [this message]
2018-04-10 13:41   ` Tony Lindgren
2018-04-10 14:12   ` Tero Kristo
2018-04-10 14:12     ` Tero Kristo
2018-04-10 15:28     ` Will Deacon
2018-04-10 15:28       ` Will Deacon
2018-04-11 12:52     ` Russell King - ARM Linux
2018-04-11 12:52       ` Russell King - ARM Linux
2018-04-11 12:57       ` Tero Kristo
2018-04-11 12:57         ` Tero Kristo
2018-04-11 12:59       ` Keerthy
2018-04-11 12:59         ` Keerthy
2018-04-11 13:10         ` Russell King - ARM Linux
2018-04-11 13:10           ` Russell King - ARM Linux
2018-04-11 14:11       ` Tony Lindgren
2018-04-11 14:11         ` Tony Lindgren
2018-04-15 14:08         ` Russell King - ARM Linux
2018-04-15 14:08           ` Russell King - ARM Linux
2018-04-15 15:50           ` Russell King - ARM Linux
2018-04-15 15:50             ` Russell King - ARM Linux

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=20180410134149.GQ5700@atomide.com \
    --to=tony@atomide.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-omap@vger.kernel.org \
    --cc=paul@pwsan.com \
    --cc=rmk+kernel@armlinux.org.uk \
    --cc=rnayak@codeaurora.org \
    --cc=t-kristo@ti.com \
    --cc=will.deacon@arm.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.