From mboxrd@z Thu Jan  1 00:00:00 1970
From: Julien Grall <julien.grall@citrix.com>
Subject: Re: xen/arm: Alternative start of day cache coherency
Date: Wed, 22 Jan 2014 19:06:53 +0000
Message-ID: <52E016CD.4020007@citrix.com>
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To: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@citrix.com>, xen-devel <xen-devel@lists.xen.org>
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On 01/22/2014 04:35 PM, Ian Campbell wrote:
> Julien,

Hi Ian,

> I wonder if the following is any better than the current stuff in
> staging for the issue you are seeing with BSD at start of day? Can you
> try it please.

Thanks for the patch! It allows me to boot FreeBSD correctly (ie with
Write-Through for the first page table) on Midway.

> It has survived >1000 bootloops on Midway and >50 on Mustang, both are
> still going.
> 
> It basically does a cache clean on all RAM mapped in the p2m. Anything
> in the cache is either the result of an earlier scrub of the page or
> something toolstack just wrote, so there is no need to be concerned
> about clean vs. invalidate -- clean is always correct.

I don't remember what was the conclusion... is it necessary to flush all
the RAM? Flushing the Kernel/initrd/DTB space should be enough.

-- 
Julien Grall