From: "Dale Farnsworth" <dale@farnsworth•org>
To: Dan Malek <dan@embeddededge•com>, linuxppc-dev@lists•linuxppc.org
Subject: Re: Patch boot/common/relocate.S to start kernel at 0x000c
Date: Tue, 4 Mar 2003 16:35:15 -0700 [thread overview]
Message-ID: <20030304233515.GC4683@rover.farnsworth.org> (raw)
In-Reply-To: <3E6534FA.9070503@embeddededge.com>
On Tue, Mar 04, 2003 at 11:21:30PM +0000, Dan Malek wrote:
> Dale Farnsworth wrote:
>
> >- nop /* used by __secondary_hold on prep (mtx) and chrp smp */
> >- nop /* used by __secondary_hold on prep (mtx) and chrp smp */
> >+ /*
> >+ * The first two words are used by __secondary_hold on SMP systems.
> >+ * The second word may be overwritten before the first cpu runs
> >+ * here, so we branch around it.
> >+ */
> >+ b __start
> >+ nop
> > nop
>
> I thought of this, but the comment on the first nop bothered me.
> Was it just a cut/paste without updating the comment, or could the nop
> and location zero be used by MP systems just like the one at location 0x04?
In __secondary_hold, location 0x4 is written by secondary cpus, and
location 0x0 is read, so I guess the comment is accurate, that both
locations are "used". Cpu 0 writes location 0 to tell the secondary
cpus they can continue.
I know the above code works for my dual-7455 system.
Thanks,
-Dale
** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/
next prev parent reply other threads:[~2003-03-04 23:35 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-03-04 19:16 Patch boot/common/relocate.S to start kernel at 0x000c Dale Farnsworth
2003-03-04 19:24 ` Dan Malek
2003-03-04 20:13 ` Dale Farnsworth
2003-03-04 20:21 ` Dan Malek
2003-03-04 23:08 ` Dale Farnsworth
2003-03-04 23:21 ` Dan Malek
2003-03-04 23:35 ` Dale Farnsworth [this message]
2003-03-04 23:42 ` Tom Rini
2003-03-05 0:07 ` Dale Farnsworth
2003-03-05 0:47 ` Paul Mackerras
2003-03-05 1:01 ` Wolfgang Denk
2003-03-05 1:03 ` Wolfgang Denk
[not found] ` <20030305022134.GR24171@kalmia.hozed.org>
2003-03-05 4:40 ` Dale Farnsworth
2003-03-05 17:07 ` Tom Rini
[not found] ` <15973.24544.124365.553602@argo.ozlabs.ibm.com>
2003-03-05 4:28 ` Dale Farnsworth
2003-03-05 9:54 ` Benjamin Herrenschmidt
2003-03-05 17:10 ` Tom Rini
2003-03-11 18:45 ` Dale Farnsworth
2003-03-05 17:24 ` Dan Malek
2003-03-13 22:38 ` Dale Farnsworth
2003-03-14 11:43 ` Gabriel Paubert
2003-03-14 17:52 ` Dale Farnsworth
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=20030304233515.GC4683@rover.farnsworth.org \
--to=dale@farnsworth$(echo .)org \
--cc=dan@embeddededge$(echo .)com \
--cc=linuxppc-dev@lists$(echo .)linuxppc.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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