From: eric.y.miao@gmail.com (Eric Miao)
To: linux-arm-kernel@lists.infradead.org
Subject: Simply disabling MMU in cpu_v7_reset doesn't work for kexec
Date: Wed, 21 Apr 2010 21:19:06 +0800 [thread overview]
Message-ID: <n2jf17812d71004210619qee8b8467u135fdbb44ff33049@mail.gmail.com> (raw)
In-Reply-To: <w2mf17812d71004210618vc68963cbn7ed50483a56140b7@mail.gmail.com>
On Wed, Apr 21, 2010 at 9:18 PM, Eric Miao <eric.y.miao@gmail.com> wrote:
> Tried the following simple code to disable MMU in cpu_v7_reset() doesn't
> seem to work for kexec reboot. I was expecting the following instructions
> after MMU is disabled are still reachable in the instruction fetching pipe.
>
.align 5
ENTRY(cpu_v7_reset)
+ mrc p15, 0, r1, c1, c0, 0 @ ctrl register
+ bic r1, r1, #0x0001 @ ...............m
+ mcr p15, 0, r1, c1, c0, 0 @ disable MMU
+ mcr p15, 0, ip, c8, c7, 0 @ invalidate I and D TLBs
mov pc, r0
ENDPROC(cpu_v7_reset)
> Not tried JTAG but posted here early in case anyone knows the correct
> sequence of disabling MMU before reset.
>
> - eric
>
next prev parent reply other threads:[~2010-04-21 13:19 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-04-21 13:18 Simply disabling MMU in cpu_v7_reset doesn't work for kexec Eric Miao
2010-04-21 13:19 ` Eric Miao [this message]
2010-04-21 19:25 ` Jamie Lokier
2010-04-21 19:48 ` Russell King - ARM Linux
2010-04-21 21:10 ` Jamie Lokier
2010-04-21 21:39 ` Russell King - ARM Linux
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=n2jf17812d71004210619qee8b8467u135fdbb44ff33049@mail.gmail.com \
--to=eric.y.miao@gmail.com \
--cc=linux-arm-kernel@lists.infradead.org \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).