qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
To: BALATON Zoltan <balaton@eik.bme.hu>
Cc: qemu-ppc@nongnu.org, qemu-devel@nongnu.org
Subject: Re: [PATCH v8 0/5] Mac Old World ROM experiment (ppc/mac_* clean ups and loading binary ROM)
Date: Sat, 17 Oct 2020 13:54:35 +0100	[thread overview]
Message-ID: <f614564a-e3e1-fc68-7f88-5983f5d41575@ilande.co.uk> (raw)
In-Reply-To: <f26e685a-4e93-c8a5-622f-5b12c71b8ac@eik.bme.hu>

On 16/10/2020 13:19, BALATON Zoltan via wrote:

> On Fri, 16 Oct 2020, Mark Cave-Ayland wrote:
>> On 16/10/2020 00:47, BALATON Zoltan via wrote:
>>> This is the cut down version of the earlier series omitting unfinished
>>> patches that I plan to rework later and rebased to Mark's qemu-macppc
>>> branch. Compared to v7 the only change is the cast to (target_ulong)
>>> from (uint32_t) as requested by Mark in patch 1.
>>
>> FWIW the reason for suggesting the cast to target_ulong is so that the same code 
>> works for both qemu-system-ppc and qemu-system-ppc64. For qemu-system-ppc that 
>> should correctly drop the sign extension from 32-bit, whilst still allowing someone 
>> to load a 64-bit ELF into qemu-system-ppc64 if requested.
>>
>> Can you confirm that the sign extension behaviour is still correct for both 
>> qemu-system-ppc and qemu-system-ppc64? If so I'm happy to give it a R-B tag.
> 
> I've tried it now again with both ppc and ppc64: both OpenBIOS and a G3 beige ROM can 
> be loaded with qemu-system-ppc but qemu-system-ppc64 fails with OpenBIOS when casting 
> to target_ulong (i think because target_ulong is 64 bit there but g3beige is still 32 
> bit but I haven't throughly debugged it). But everything works with my original 
> uint32_t cast, so ditch it and use my original version. Should I resubmit or you can 
> fix up? (I think I wait until it's clear if this will be taken by David or you and 
> send a fixed version cc-ing David if this is decided to go through the PPC queue.)

Hmmm yes I see that qemu-system-ppc64 fails because target_ulong will always 
represent a 64-bit quantity, even if you request a 32-bit CPU. Rather than add some 
CPU-specific code let's keep the uint32_t cast for now as I would hope it is unlikely 
someone would load an ELF in high memory, and perhaps the sign-extended address bug 
will get fixed later.

With the cast reverted to uint32_t then for patches 1 and 2:
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

If you can send a v9 with the cast fixed I'll apply this to my qemu-macppc branch 
right away.


ATB,

Mark.


  reply	other threads:[~2020-10-17 12:55 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-15 23:47 [PATCH v8 0/5] Mac Old World ROM experiment (ppc/mac_* clean ups and loading binary ROM) BALATON Zoltan via
2020-10-15 23:47 ` [PATCH v8 4/5] mac_oldworld: Drop some variables BALATON Zoltan via
2020-10-15 23:47 ` [PATCH v8 1/5] mac_oldworld: Allow loading binary ROM image BALATON Zoltan via
2020-10-15 23:47 ` [PATCH v8 5/5] mac_oldworld: Change PCI address of macio to match real hardware BALATON Zoltan via
2020-10-15 23:47 ` [PATCH v8 2/5] mac_newworld: Allow loading binary ROM image BALATON Zoltan via
2020-10-15 23:47 ` [PATCH v8 3/5] mac_oldworld: Drop a variable, use get_system_memory() directly BALATON Zoltan via
2020-10-16  9:58 ` [PATCH v8 0/5] Mac Old World ROM experiment (ppc/mac_* clean ups and loading binary ROM) Mark Cave-Ayland
2020-10-16 12:19   ` BALATON Zoltan via
2020-10-17 12:54     ` Mark Cave-Ayland [this message]
2020-10-17 15:56       ` BALATON Zoltan via
2020-10-18 16:01         ` Mark Cave-Ayland
2020-10-16 13:05   ` Philippe Mathieu-Daudé
2020-10-17 16:39     ` BALATON Zoltan via
2020-10-17 17:44       ` Philippe Mathieu-Daudé

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=f614564a-e3e1-fc68-7f88-5983f5d41575@ilande.co.uk \
    --to=mark.cave-ayland@ilande.co.uk \
    --cc=balaton@eik.bme.hu \
    --cc=qemu-devel@nongnu.org \
    --cc=qemu-ppc@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).