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From: Julien Grall <julien.grall@citrix.com>
To: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Tim Deegan <tim@xen.org>, Chen Baozi <baozich@gmail.com>,
	Stefano Stabellini <stefano.stabellini@citrix.com>,
	Andre Przywara <andre.przywara@linaro.org>,
	xen-devel <xen-devel@lists.xen.org>
Subject: Re: xen: arm: beginning the removal of mode_switch.S
Date: Wed, 21 Aug 2013 13:36:12 +0100	[thread overview]
Message-ID: <5214B43C.7090807@citrix.com> (raw)
In-Reply-To: <1377007861.9517.52.camel@kazak.uk.xensource.com>

On 08/20/2013 03:11 PM, Ian Campbell wrote:
> So this is all pretty complex (not to mention hard to describe in ASCII)
> and in lockstep, the secondary cpus wait twice once on the original
> smp_cpu_up and then again on the relocated version. There is a subtle
> reliance on the 1:1 mapping being retained in the original copy of the
> page tables.

Thanks for this ASCII!

> I think the original wait is actually a workaround for lack of firmware
> on the fastmodels, and should be implemented by either the firmware or
> bootwrapper.

BTW, this wait is an issue when the boot CPU ID is not equal to 0.

I gave a quick try to move kick cpus after the HYP mode switch in
assembly and I'm unable to boot secondary cpus on the Versatile Express.
I guess, on the VE secondary cpus can only be "kick" in secure mode.

Cheers,

-- 
Julien Grall

  reply	other threads:[~2013-08-21 12:36 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-08-15 11:51 xen: arm: beginning the removal of mode_switch.S Ian Campbell
2013-08-15 13:46 ` Tim Deegan
2013-08-15 14:07   ` Ian Campbell
2013-08-15 16:53     ` Tim Deegan
2013-08-15 20:48       ` Ian Campbell
2013-08-15 17:05 ` Julien Grall
2013-08-15 20:51   ` Ian Campbell
2013-08-16 10:12     ` Julien Grall
2013-08-16 15:04       ` Ian Campbell
2013-08-16 15:11         ` Andre Przywara
2013-08-16 15:44         ` Julien Grall
2013-08-20 14:11           ` Ian Campbell
2013-08-21 12:36             ` Julien Grall [this message]
2013-08-21 12:42               ` Andre Przywara
2013-08-22  7:19                 ` Ian Campbell
2013-08-15 20:55   ` Andre Przywara
2013-08-15 21:14     ` Ian Campbell
2013-08-19 17:46     ` Christoffer Dall
2013-08-20  9:37       ` Ian Campbell

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