All of lore.kernel.org
 help / color / mirror / Atom feed
From: Anthony Liguori <anthony@codemonkey.ws>
To: Peter Maydell <peter.maydell@linaro.org>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Liu Ping Fan" <pingfank@linux.vnet.ibm.com>,
	"Alexander Graf" <agraf@suse.de>,
	"qemu-devel Developers" <qemu-devel@nongnu.org>,
	"qemu-ppc@nongnu.org list:PowerPC" <qemu-ppc@nongnu.org>,
	"Paolo Bonzini" <pbonzini@redhat.com>,
	"Jan Kiszka" <jan.kiszka@web.de>,
	"Andreas Färber" <afaerber@suse.de>,
	"Hervé Poussineau" <hpoussin@reactos.org>
Subject: Re: [Qemu-devel] [Qemu-ppc] [PATCH v3 11/14] ioport: Switch dispatching to memory core layer
Date: Mon, 15 Jul 2013 09:01:13 -0500	[thread overview]
Message-ID: <87sizfudli.fsf@codemonkey.ws> (raw)
In-Reply-To: <CAFEAcA9qGE4pgM_DBJ2w0d16Jef8W6GkUbOTQvCFm3c-EZCYnA@mail.gmail.com>

Peter Maydell <peter.maydell@linaro.org> writes:

> On 12 July 2013 23:50, Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote:
>> Our experience is that it actually works fine for almost everything
>> except virtio :-) ie mostly TARGET_WORDS_BIGENDIAN is irrelevant (and
>> should be).
>
> I agree that TARGET_WORDS_BIGENDIAN *should* go away, but
> it exists currently. Do you actually implement a CPU which
> does dynamic endianness flipping?

TCG already supports bi-endianness for PPC.  Grep for 'le_mode' in
target-ppc/translate.c to see how the TCG instruction stream is affected
by it.

On PPC, le_mode only really affects load/stores and instruction
decoding.  Any shared data structures between the CPU and OS remain big
endian.

So TARGET_WORDS_BIGENDIAN is still accurate even when le_mode=1.  It's
not the semantic equivalent of changing TARGET_WORDS.

Regards,

Anthony Liguori

> Is it at all efficient
> in the config which is the opposite of whatever
> TARGET_WORDS_BIGENDIAN says?
>
> thanks
> -- PMM

  parent reply	other threads:[~2013-07-15 14:01 UTC|newest]

Thread overview: 66+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-06-22  6:06 [Qemu-devel] [PATCH v3 00/14] Refactor portio dispatching Jan Kiszka
2013-06-22  6:06 ` [Qemu-devel] [PATCH v3 01/14] adlib: replace register_ioport* Jan Kiszka
2013-06-22  6:06 ` [Qemu-devel] [PATCH v3 02/14] applesmc: " Jan Kiszka
2013-06-22  6:06 ` [Qemu-devel] [PATCH v3 03/14] wdt_ib700: " Jan Kiszka
2013-06-22  6:06 ` [Qemu-devel] [PATCH v3 04/14] i82374: " Jan Kiszka
2013-06-22  6:06 ` [Qemu-devel] [PATCH v3 05/14] prep: " Jan Kiszka
2013-06-22  6:06 ` [Qemu-devel] [PATCH v3 06/14] vt82c686: " Jan Kiszka
2013-06-22  6:07 ` [Qemu-devel] [PATCH v3 07/14] Privatize register_ioport_read/write Jan Kiszka
2013-06-22  6:07 ` [Qemu-devel] [PATCH v3 08/14] isa: implement isa_is_ioport_assigned via memory_region_find Jan Kiszka
2013-06-22  6:07 ` [Qemu-devel] [PATCH v3 09/14] vmware-vga: Accept unaligned I/O accesses Jan Kiszka
2013-06-22  6:07 ` [Qemu-devel] [PATCH v3 10/14] xen: Mark fixed platform I/O as unaligned Jan Kiszka
2013-06-22  6:07 ` [Qemu-devel] [PATCH v3 11/14] ioport: Switch dispatching to memory core layer Jan Kiszka
2013-06-23 20:50   ` Hervé Poussineau
2013-06-24  6:07     ` Jan Kiszka
2013-07-11 12:29       ` Alexander Graf
2013-07-11 12:34         ` Alexander Graf
2013-07-11 12:46           ` Andreas Färber
2013-07-11 12:48             ` Alexander Graf
2013-07-11 13:28               ` Alexander Graf
2013-07-11 13:35                 ` Alexander Graf
2013-07-11 22:30                 ` [Qemu-devel] [Qemu-ppc] " Benjamin Herrenschmidt
2013-07-11 22:32                 ` Benjamin Herrenschmidt
2013-07-12  3:18                   ` Alexander Graf
2013-07-12 11:35                     ` Benjamin Herrenschmidt
2013-07-12 17:04                       ` Hervé Poussineau
2013-07-12 19:06                         ` Anthony Liguori
2013-07-12 22:59                           ` Benjamin Herrenschmidt
2013-07-12 22:39                         ` Benjamin Herrenschmidt
2013-07-12 17:49                       ` Anthony Liguori
2013-07-12 18:26                         ` Peter Maydell
2013-07-12 22:50                           ` Benjamin Herrenschmidt
2013-07-12 23:10                             ` Peter Maydell
2013-07-12 23:49                               ` Benjamin Herrenschmidt
2013-07-15 14:01                               ` Anthony Liguori [this message]
2013-07-15 14:10                                 ` Peter Maydell
2013-07-15 14:16                                 ` Benjamin Herrenschmidt
2013-07-12 22:44                         ` Benjamin Herrenschmidt
2013-07-13 14:38             ` [Qemu-devel] " Paolo Bonzini
2013-07-13 15:22               ` Anthony Liguori
2013-07-13 18:11                 ` Hervé Poussineau
2013-07-14  6:15                 ` Paolo Bonzini
2013-07-14 13:05                   ` Anthony Liguori
2013-07-14 14:58                     ` Peter Maydell
2013-07-14 15:18                       ` Anthony Liguori
2013-07-14 16:50                         ` Peter Maydell
2013-07-16  7:18                         ` Jan Kiszka
2013-07-16  7:33                           ` Paolo Bonzini
2013-07-16 16:59                             ` Hervé Poussineau
2013-07-16 17:12                               ` Paolo Bonzini
2013-07-12 12:56           ` Anthony Liguori
2013-07-12 14:30             ` Alexander Graf
2013-07-19 11:09         ` [Qemu-devel] BUG: " Alexey Kardashevskiy
2013-07-19 12:49           ` Paolo Bonzini
2013-07-19 15:48             ` Alexey Kardashevskiy
2013-07-20  0:55               ` Alexey Kardashevskiy
2013-07-20  1:11                 ` Alexey Kardashevskiy
2013-07-20 10:11                   ` Paolo Bonzini
2013-07-20 20:53                     ` Edgar E. Iglesias
2013-07-21 15:13                     ` Hervé Poussineau
2013-07-22 10:25                       ` Paolo Bonzini
2013-06-24  8:45     ` [Qemu-devel] [PATCH v4 " Jan Kiszka
2013-07-12 19:36     ` [Qemu-devel] [PATCH v3 " Anthony Liguori
2013-06-22  6:07 ` [Qemu-devel] [PATCH v3 12/14] ioport: Remove unused old dispatching services Jan Kiszka
2013-06-22  6:07 ` [Qemu-devel] [PATCH v3 13/14] vmport: Disentangle read handler type from portio Jan Kiszka
2013-06-22  6:07 ` [Qemu-devel] [PATCH v3 14/14] ioport: Move portio types to ioport.h Jan Kiszka
2013-06-23 20:45 ` [Qemu-devel] [PATCH v3 00/14] Refactor portio dispatching Hervé Poussineau

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=87sizfudli.fsf@codemonkey.ws \
    --to=anthony@codemonkey.ws \
    --cc=afaerber@suse.de \
    --cc=agraf@suse.de \
    --cc=benh@kernel.crashing.org \
    --cc=hpoussin@reactos.org \
    --cc=jan.kiszka@web.de \
    --cc=pbonzini@redhat.com \
    --cc=peter.maydell@linaro.org \
    --cc=pingfank@linux.vnet.ibm.com \
    --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 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.