qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Blue Swirl <blauwirbel@gmail.com>
To: qemu-devel@nongnu.org
Cc: Alexander Graf <alex@csgraf.de>
Subject: Re: [Qemu-devel] [PATCH] PPC: Use correct values for 970 interrupts and hreset
Date: Sat, 28 Feb 2009 17:21:34 +0200	[thread overview]
Message-ID: <f43fc5580902280721x39ad3c25y1d73b611a73cabf8@mail.gmail.com> (raw)
In-Reply-To: <1235832403-29902-1-git-send-email-agraf@suse.de>

On 2/28/09, Alexander Graf <agraf@suse.de> wrote:
> The 970 doesn't set exception prefix values by default. According to
>  the ISA it just jumps to real mode with nip=vector.
>
>  Because of that the current hreset_vector is rendered invalid. Before,
>  it would go to excp_prefix (ROM base) + 0x100 (reset vector) and get
>  into the firmware.
>
>  But with the corrected excp_prefix, we now have to jump to the real
>  entry point, which is at 0xFFFFFFFC.

I don't think this is correct. 970FX uses HIOR to specify the
exception vector base, please see "IBM PowerPC 970FX RISC
Microprocessor", page 273.

>From OpenBIOS viewpoint both vectors are OK.

>  I can't imagine how any OS that does memory management itself could have
>  possibly worked with the code as it was.

Maybe Qemu uses the 604 exception prefix somewhere.

  reply	other threads:[~2009-02-28 15:21 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-02-28 14:46 [Qemu-devel] [PATCH] PPC: Use correct values for 970 interrupts and hreset Alexander Graf
2009-02-28 15:21 ` Blue Swirl [this message]
2009-02-28 15:27   ` Alexander Graf
2009-02-28 15:32   ` Alexander Graf
2009-02-28 15:49     ` Blue Swirl

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=f43fc5580902280721x39ad3c25y1d73b611a73cabf8@mail.gmail.com \
    --to=blauwirbel@gmail.com \
    --cc=alex@csgraf.de \
    --cc=qemu-devel@nongnu.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).