linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: linux@arm.linux.org.uk (Russell King - ARM Linux)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 2/4] irqchip: bcm2836: Add SMP support for the 2836
Date: Sat, 2 Jan 2016 10:27:47 +0000	[thread overview]
Message-ID: <20160102102747.GO8644@n2100.arm.linux.org.uk> (raw)
In-Reply-To: <1451166444-11044-3-git-send-email-eric@anholt.net>

On Sat, Dec 26, 2015 at 01:47:22PM -0800, Eric Anholt wrote:
> +int __init bcm2836_smp_boot_secondary(unsigned int cpu,
> +				      struct task_struct *idle)
> +{
> +	unsigned long secondary_startup_phys =
> +		(unsigned long)virt_to_phys((void *)secondary_startup);
> +
> +	dsb();
> +	writel(secondary_startup_phys,
> +	       intc.base + LOCAL_MAILBOX3_SET0 + 16 * cpu);

Please explain why you need this dsb() - I can't see a reason for it.
writel() has a barrier internally prior to writing the register, and
therefore I think the above dsb() is entirely redundant.

-- 
RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.

  reply	other threads:[~2016-01-02 10:27 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-12-26 21:47 [PATCH 0/4] bcm2836 (Raspberry Pi 2) interrupt controller updates for 4.5 Eric Anholt
2015-12-26 21:47 ` [PATCH 1/4] irqchip: bcm2836: Fix initialization of the LOCAL_IRQ_CNT*IRQ timers Eric Anholt
2015-12-26 21:47 ` [PATCH 2/4] irqchip: bcm2836: Add SMP support for the 2836 Eric Anholt
2016-01-02 10:27   ` Russell King - ARM Linux [this message]
2016-01-02 16:05     ` Andrea Merello
2015-12-26 21:47 ` [PATCH 3/4] irqchip: bcm2836: tolerate IRQs while no flag is set in ISR Eric Anholt
2015-12-26 21:47 ` [PATCH 4/4] irqchip: bcm2836: make code more readable Eric Anholt

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=20160102102747.GO8644@n2100.arm.linux.org.uk \
    --to=linux@arm.linux.org.uk \
    --cc=linux-arm-kernel@lists.infradead.org \
    /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).