From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
To: valerij zaporogeci <vlrzprgts@gmail.com>
Cc: edk2-devel <edk2-devel@lists.01.org>
Subject: Re: flat mapping vs identity mapping on ARM
Date: Thu, 22 Sep 2016 16:03:20 +0100 [thread overview]
Message-ID: <CAKv+Gu92SzouihE0cuMNNjrDQgo2-FeNcQBnCXQtyN=OmgsDBg@mail.gmail.com> (raw)
In-Reply-To: <CANPuzFxJhYPRv16o0Z1w0F0c22mvzo6sW6hGm43qEOZ4U8LRoQ@mail.gmail.com>
On 22 September 2016 at 15:30, valerij zaporogeci <vlrzprgts@gmail.com> wrote:
> In the ARM architecture, there is such a thing - "flat mapping", where
> MMU stage 1 is disabled and the mapping done is 1:1 and attributes set
> to the predefined values.
What do you mean by 'attributes set to the predefined values' ?
> Did I understand right, that this is NOT what UEFI means by "identity
> mapping" with MMU enabled? And in the latter case there is need to
> create all those page tables and stuff, setting 1:1 mapping between VA
> and PA? If so, why to do that? Why "flat mapping" isn't what UEFI
> would love to see as its mapping regime?
On ARM, you need to enable the MMU in order to enable the Dcache.
next prev parent reply other threads:[~2016-09-22 15:03 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-22 14:30 flat mapping vs identity mapping on ARM valerij zaporogeci
2016-09-22 15:03 ` Ard Biesheuvel [this message]
2016-09-22 15:19 ` valerij zaporogeci
2016-09-22 15:22 ` Ard Biesheuvel
2016-09-22 15:23 ` Ard Biesheuvel
2016-09-22 15:34 ` Andrew Fish
2016-09-22 19:14 ` valerij zaporogeci
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