From: Christoffer Dall <cdall@linaro.org>
To: Raz <raziebe@gmail.com>
Cc: kvmarm@lists.cs.columbia.edu
Subject: Re: A question about TTBRs
Date: Fri, 24 Feb 2017 11:22:40 +0100 [thread overview]
Message-ID: <20170224102240.GG1409@cbox> (raw)
In-Reply-To: <CAPB=Z-omrvPjkjmQWfLNWtA86XJzEM1wCB1Rbc-2dnd0iUtaDA@mail.gmail.com>
On Fri, Feb 24, 2017 at 09:55:09AM +0000, Raz wrote:
> Hello
> I am reading the arm8a book. According to the documentation the output
> address of each level 3 entry in TTBRx_EL1points to an address in the
> physical memory.
> By looking in the mmu tab in the DS5 studio I can see the TTBRs tables.
>
> What I do not understand is why while I have 2GB of RAM in the FVP (
> /proc/meminfo ) some page entries ( level 3 ) of the ttbr points to memory
> above 4GB; for instance:
>
> Output address NP:0xF794D000
>
> Doesn't the physical memory starts at address zero ? if not, where its
> starting point is configured?
It depends on your particular system where RAM starts, and it does not
necessarily start at zero. You'd have to check the documentation of
your model or hardware or look at the device tree you use, for example.
-Christoffer
next prev parent reply other threads:[~2017-02-24 10:21 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-24 9:55 A question about TTBRs Raz
2017-02-24 10:22 ` Christoffer Dall [this message]
2017-02-24 12:10 ` Mark Rutland
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=20170224102240.GG1409@cbox \
--to=cdall@linaro.org \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=raziebe@gmail.com \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.