From: Hollis Blanchard <hollis@penguinppc.org>
To: Olof Johansson <olof@lixom.net>
Cc: paulus@samba.org, linuxppc-dev@lists.ozlabs.org,
Ian Munsie <imunsie@au1.ibm.com>,
linux-kernel@vger.kernel.org
Subject: Re: Introduce support for little endian PowerPC
Date: Thu, 7 Oct 2010 09:25:27 -0700 [thread overview]
Message-ID: <AANLkTim0+SU3EqRe6x5aXR+G-Gczv6gBSrrdinXQavSa@mail.gmail.com> (raw)
In-Reply-To: <20101001220343.GA10494@lixom.net>
On Fri, Oct 1, 2010 at 3:03 PM, Olof Johansson <olof@lixom.net> wrote:
> On Sat, Oct 02, 2010 at 06:51:55AM +1000, Benjamin Herrenschmidt wrote:
>> On Fri, 2010-10-01 at 12:59 -0500, Kumar Gala wrote:
>> > I'm not against it, and I agree some of the patches seem like good
>> > clean up. =A0I'm concerned about this bit rotting pretty quickly.
>>
>> Maybe. Most of it doesn't seem to be that bit-rottable.
>>
>> The changes to the asm stuff in misc_32.S for example are functions we
>> never ever touch once written (libgcc replacements) so I don't see them
>> rotting more with LE support than they did with BE :-)
>
> Does KVM/qemu support running LE guest on BE host? That'd help keeping
> the bitrot lower. :)
Surprisingly, qemu has very poor support for the concept of
endianness. The fact that BE PowerPC works on both BE and LE hosts in
Qemu today is more accidental than anything else (the special curse of
endianness is that two wrongs make a right). Supporting LE PowerPC
guests would be a dramatic effort, and I'm pretty sure it would impact
other qemu architectures as well.
-Hollis
next prev parent reply other threads:[~2010-10-07 16:25 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-10-01 7:05 Introduce support for little endian PowerPC Ian Munsie
2010-10-01 7:05 ` [PATCH 01/18] powerpc: Add ability to build little endian kernels Ian Munsie
2010-10-01 9:18 ` Kumar Gala
2010-10-01 11:28 ` Josh Boyer
2010-10-01 12:09 ` Benjamin Herrenschmidt
2010-10-01 11:40 ` Josh Boyer
2010-10-01 12:22 ` Benjamin Herrenschmidt
2010-10-01 7:05 ` [PATCH 02/18] powerpc: Add CROSSBE_COMPILE to build big endian boot wrapper Ian Munsie
2010-10-01 7:13 ` Geert Uytterhoeven
2010-10-01 7:19 ` Ian Munsie
2010-10-01 7:05 ` [PATCH 03/18] powerpc: Support parsing a little endian kernel from zImage wrapper Ian Munsie
2010-10-01 7:05 ` [PATCH 04/18] powerpc: Allow taishan platform to boot a little endian kernel Ian Munsie
2010-10-01 7:05 ` [PATCH 05/18] powerpc: Wire up 44x little endian boot for remaining 44x targets Ian Munsie
2010-10-01 11:27 ` Josh Boyer
2010-10-06 1:28 ` Ian Munsie
2010-10-06 1:55 ` Josh Boyer
2010-10-06 2:10 ` Sean MacLennan
2010-10-01 7:05 ` [PATCH 06/18] powerpc 44x: Set E bit in TLBs and PTEs when CPU is in little endian mode Ian Munsie
2010-10-01 7:06 ` [PATCH 07/18] powerpc: Use generic bitops for little endian bitmap operations Ian Munsie
2010-10-01 7:06 ` [PATCH 08/18] powerpc: Include the appropriate endianness header Ian Munsie
2010-10-01 7:06 ` [PATCH 09/18] powerpc: Support device tree regardless of CPU endianness Ian Munsie
2010-10-03 3:15 ` Grant Likely
2010-10-03 6:22 ` Benjamin Herrenschmidt
2010-10-01 7:06 ` [PATCH 10/18] powerpc: Support endian agnostic MMIO Ian Munsie
2010-10-01 7:06 ` [PATCH 11/18] powerpc: Make assembly endian agnostic when accessing 64bit values Ian Munsie
2010-10-01 7:06 ` [PATCH 12/18] powerpc 44x: Handle TLB miss regardless of endianness Ian Munsie
2010-10-01 7:06 ` [PATCH 13/18] powerpc 44x: Make DCR endianness agnostic Ian Munsie
2010-10-01 7:06 ` [PATCH 14/18] powerpc, of_serial: Endianness issues setting up the serial ports Ian Munsie
2010-10-07 23:23 ` Grant Likely
2010-10-01 7:06 ` [PATCH 15/18] mtd: Fix endianness issues from device tree Ian Munsie
2010-10-01 19:29 ` Artem Bityutskiy
2010-10-01 7:06 ` [PATCH 16/18] powerpc: Fix endianness issues in alignment handler Ian Munsie
2010-10-01 7:06 ` [PATCH 17/18] net: Fix endianess issues in IBM newemac driver Ian Munsie
2010-10-01 7:06 ` [PATCH 18/18] powerpc: Fix jiffies variable on little endian Ian Munsie
2010-10-01 9:02 ` Introduce support for little endian PowerPC Kumar Gala
2010-10-01 11:30 ` Josh Boyer
2010-10-01 11:55 ` Gary Thomas
2010-10-01 12:15 ` Benjamin Herrenschmidt
2010-10-01 12:37 ` Gary Thomas
2010-10-01 12:14 ` Benjamin Herrenschmidt
2010-10-01 16:20 ` Michel Dänzer
2010-10-01 20:50 ` Benjamin Herrenschmidt
2010-10-04 10:30 ` Michel Dänzer
2010-10-04 22:50 ` Benjamin Herrenschmidt
2010-10-01 17:59 ` Kumar Gala
2010-10-01 20:51 ` Benjamin Herrenschmidt
2010-10-01 22:03 ` Olof Johansson
2010-10-01 22:28 ` Benjamin Herrenschmidt
2010-10-07 16:25 ` Hollis Blanchard [this message]
2010-10-01 11:36 ` Josh Boyer
2010-10-01 12:21 ` Benjamin Herrenschmidt
2010-10-06 1:04 ` Ian Munsie
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