From: arnd@arndb•de (Arnd Bergmann)
To: linux-arm-kernel@lists•infradead.org
Subject: Android and compatibility with deprecated armv7 instructions
Date: Mon, 7 Jul 2014 23:26:38 +0200 [thread overview]
Message-ID: <201407072326.38975.arnd@arndb.de> (raw)
In-Reply-To: <20140707143545.GD32276@arm.com>
On Monday 07 July 2014, Catalin Marinas wrote:
> > - running an old arm7tdmi rtos build that you lost the source code for
> > but that would be cheaper to run on a new cortex-a7 emulating the
> > peripherals than to rewrite and revalidate
>
> That's a too rare case to justify the additional CPU gates.
For trapping just a few extra instructions? That doesn't sound too
expensive.
> > - running OABI binaries in a 32-bit guest on an armv8 (or future version)
>
> But you can already run an ARMv7 kernel now with OABI enabled on an
> ARMv8 (either native or guest).
>
> > - testing armv4 kernel builds in a kvm guest using qemu models
>
> Again, this would require pre-ARMv6 MMU to be carried over for little
> benefit (well, just to developers but hard to justify ARMv4 hardware
> compatibility to marketing).
I don't think anybody was talking about emulating the MMU in hardware.
It doesn't have to be fast, so you'd just do shadow page tables.
Arnd
next prev parent reply other threads:[~2014-07-07 21:26 UTC|newest]
Thread overview: 76+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-07-01 23:06 Android and compatibility with deprecated armv7 instructions Colin Cross
2014-07-01 23:42 ` Olof Johansson
2014-07-01 23:48 ` Mark Brown
2014-07-02 10:01 ` Will Deacon
2014-07-02 15:48 ` Colin Cross
2014-07-02 16:16 ` Will Deacon
2014-07-02 18:03 ` Christopher Covington
2014-07-02 18:25 ` Will Deacon
2014-07-02 19:47 ` Mark Brown
2014-07-05 21:26 ` Rob Herring
2014-07-02 16:39 ` Mark Brown
2014-07-02 17:01 ` Will Deacon
2014-07-02 17:33 ` Mark Brown
2014-07-02 22:14 ` Grant Likely
2014-07-03 10:41 ` Catalin Marinas
2014-07-03 14:28 ` Arnd Bergmann
2014-07-03 15:00 ` Russell King - ARM Linux
2014-07-03 15:40 ` Grant Likely
2014-07-03 17:13 ` Catalin Marinas
2014-07-03 17:48 ` Russell King - ARM Linux
2014-07-03 18:15 ` Arnd Bergmann
2014-07-03 18:30 ` Russell King - ARM Linux
2014-07-03 18:37 ` Will Deacon
2014-07-03 18:52 ` Russell King - ARM Linux
2014-07-03 19:00 ` Will Deacon
2014-07-04 8:57 ` Catalin Marinas
2014-07-04 9:25 ` Russell King - ARM Linux
2014-07-04 10:12 ` Arnd Bergmann
2014-07-04 14:09 ` Dr. David Alan Gilbert
2014-07-04 12:56 ` Grant Likely
2014-07-04 13:31 ` Russell King - ARM Linux
2014-07-03 18:46 ` Will Deacon
2014-07-03 18:53 ` Arnd Bergmann
2014-07-03 19:07 ` Russell King - ARM Linux
2014-07-03 19:40 ` Arnd Bergmann
2014-07-04 13:25 ` Grant Likely
2014-07-03 16:22 ` Grant Likely
2014-07-03 17:05 ` Russell King - ARM Linux
2014-07-03 17:32 ` Will Deacon
2014-07-03 18:23 ` Arnd Bergmann
2014-07-03 18:38 ` Peter Maydell
2014-07-03 18:40 ` Will Deacon
2014-07-03 18:32 ` Mark Brown
2014-07-03 22:16 ` Måns Rullgård
2014-07-03 22:47 ` Russell King - ARM Linux
2014-07-04 7:08 ` Ard Biesheuvel
2014-07-04 8:24 ` Catalin Marinas
2014-07-04 8:33 ` Ard Biesheuvel
2014-07-04 9:21 ` Måns Rullgård
2014-07-04 9:34 ` Russell King - ARM Linux
2014-07-04 10:21 ` Måns Rullgård
2014-07-04 10:33 ` Russell King - ARM Linux
2014-07-04 11:00 ` Ard Biesheuvel
2014-07-04 17:28 ` Nicolas Pitre
2014-07-03 17:43 ` Catalin Marinas
2014-07-04 13:22 ` Grant Likely
2014-07-04 19:24 ` Mark Brown
2014-07-04 19:33 ` Arnd Bergmann
2014-07-04 22:06 ` Måns Rullgård
2014-07-04 22:08 ` Mark Brown
2014-07-05 11:14 ` Catalin Marinas
2014-07-05 11:25 ` Russell King - ARM Linux
2014-07-05 16:43 ` Mark Brown
2014-07-05 17:06 ` Catalin Marinas
2014-07-05 18:43 ` Arnd Bergmann
2014-07-05 21:19 ` Catalin Marinas
2014-07-06 15:39 ` Arnd Bergmann
2014-07-07 13:59 ` Janne Grunau
2014-07-07 14:52 ` Catalin Marinas
2014-07-07 17:52 ` Janne Grunau
2014-07-07 15:43 ` Peter Maydell
2014-07-08 5:28 ` Måns Rullgård
2014-07-07 14:35 ` Catalin Marinas
2014-07-07 21:26 ` Arnd Bergmann [this message]
2014-07-07 12:28 ` Grant Likely
2014-07-07 18:35 ` Colin Cross
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