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Subject: Re: [PATCH 3/6] 8xx: get rid of _PAGE_HWWRITE dependency in MMU.
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Joakim Tjernlund <joakim.tjernlund@transmode.se>
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Date: Tue, 06 Oct 2009 17:45:47 +1100
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Cc: Scott Wood <scottwood@freescale.com>,
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On Tue, 2009-10-06 at 08:15 +0200, Joakim Tjernlund wrote:

> Yes, I would too but TLB Miss knows nothing about load/store, protection etc.
> because DSISR isn't set. So I cannot see any other way than the TLB Error way.

Hrm... that MMU really sucks more than I thought :-(

I'll go read the manual and think about that a bit more.

> But I guess BookE knows if it is a load or store in TLB Miss?
> Then it can emulate changed bit I guess.

Yes, it knows.

Cheers,
Ben.