From: Arnout Vandecappelle <arnout@mind.be>
To: buildroot@busybox.net
Subject: [Buildroot] [PATCH v2 04/17] uclibc: add patches to simplify Thumb handling
Date: Sat, 19 Mar 2016 16:46:04 +0100 [thread overview]
Message-ID: <56ED743C.9070500@mind.be> (raw)
In-Reply-To: <1458335299-27409-5-git-send-email-thomas.petazzoni@free-electrons.com>
On 03/18/16 22:08, Thomas Petazzoni wrote:
> This commit adds a number of patches to uClibc that radically
> simplifies the Thumb handling. uClibc currently has three options that
> you need to toggle on Thumb configurations depending on the specific
> ARM CPU being targeted.
>
> However, it turns out that none of those options are necessary:
>
> - USE_BX can simply be guessed by looking at the ARM core being
> used. The bx instruction is available for all ARM cores >=
> ARMv4T. This is exactly what glibc is doing.
>
> - USE_LDREXSTREX can also be guessed by looking at the ARM core being
> used: whenever you have Thumb2, ldrex/strex is available.
>
> - COMPILE_IN_THUMB becomes useless, since all it does is passing
> -mthumb. But just like the uClibc config options to set
> --march=<foo> have been removed a long time ago, there's no need to
> -have an option to pass -mthumb.
>
> Signed-off-by: Thomas Petazzoni<thomas.petazzoni@free-electrons.com>
Reviewed-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Upstream status? Knowing Waldemar's lightning reflexes, we will probably just
bump the uClibc version rather than having these patches in Buildroot :-)
Regards,
Arnout
> ---
> .../0001-arm-remove-use-of-USE_BX-option.patch | 53 ++++++++++++++++++++++
> package/uclibc/0002-arm-remove-USE_BX-option.patch | 40 ++++++++++++++++
> .../0003-arm-remove-use-of-USE_LDREXSTREX.patch | 49 ++++++++++++++++++++
> .../uclibc/0004-arm-remove-USE_LDREXSTREX.patch | 34 ++++++++++++++
> .../uclibc/0005-arm-remove-COMPILE_IN_THUMB.patch | 43 ++++++++++++++++++
> 5 files changed, 219 insertions(+)
> create mode 100644 package/uclibc/0001-arm-remove-use-of-USE_BX-option.patch
> create mode 100644 package/uclibc/0002-arm-remove-USE_BX-option.patch
> create mode 100644 package/uclibc/0003-arm-remove-use-of-USE_LDREXSTREX.patch
> create mode 100644 package/uclibc/0004-arm-remove-USE_LDREXSTREX.patch
> create mode 100644 package/uclibc/0005-arm-remove-COMPILE_IN_THUMB.patch
--
Arnout Vandecappelle arnout at mind be
Senior Embedded Software Architect +32-16-286500
Essensium/Mind http://www.mind.be
G.Geenslaan 9, 3001 Leuven, Belgium BE 872 984 063 RPR Leuven
LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle
GPG fingerprint: 7493 020B C7E3 8618 8DEC 222C 82EB F404 F9AC 0DDF
next prev parent reply other threads:[~2016-03-19 15:46 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-03-18 21:08 [Buildroot] [PATCH v2 00/17] ARM Cortex-M support and STM32 defconfigs Thomas Petazzoni
2016-03-18 21:08 ` [Buildroot] [PATCH v2 01/17] arch/arm: introduce and use BR2_ARM_CPU_ARMV7M Thomas Petazzoni
2016-03-18 22:30 ` Yann E. MORIN
2016-03-19 13:33 ` Thomas Petazzoni
2016-03-19 13:59 ` Yann E. MORIN
2016-03-19 14:08 ` Thomas Petazzoni
2016-03-18 21:08 ` [Buildroot] [PATCH v2 02/17] arch/arm: Cortex-M3 provides only Thumb-2 Thomas Petazzoni
2016-03-18 22:34 ` Yann E. MORIN
2016-03-19 15:33 ` Arnout Vandecappelle
2016-03-18 21:08 ` [Buildroot] [PATCH v2 03/17] arch/arm: add Cortex-M4 entry Thomas Petazzoni
2016-03-18 22:41 ` Yann E. MORIN
2016-03-18 21:08 ` [Buildroot] [PATCH v2 04/17] uclibc: add patches to simplify Thumb handling Thomas Petazzoni
2016-03-19 15:46 ` Arnout Vandecappelle [this message]
2016-03-29 22:14 ` Thomas Petazzoni
2016-03-18 21:08 ` [Buildroot] [PATCH v2 05/17] uclibc: remove USE_BX handling Thomas Petazzoni
2016-03-19 15:47 ` Arnout Vandecappelle
2016-03-18 21:08 ` [Buildroot] [PATCH v2 06/17] uclibc: gcc >= 4.9 can build a thumb/thread uclibc Thomas Petazzoni
2016-03-19 15:53 ` Arnout Vandecappelle
2016-03-29 22:18 ` Thomas Petazzoni
2016-03-29 22:49 ` Arnout Vandecappelle
2016-03-18 21:08 ` [Buildroot] [PATCH v2 07/17] uclibc: disable DOPIC on ARM FLAT Thomas Petazzoni
2016-03-19 16:11 ` Arnout Vandecappelle
2016-03-29 22:20 ` Thomas Petazzoni
2016-03-19 19:27 ` Ezequiel Garcia
2016-03-19 20:50 ` Thomas Petazzoni
2016-03-20 1:59 ` Ezequiel Garcia
2016-03-18 21:08 ` [Buildroot] [PATCH v2 08/17] uclibc: context functions are not Thumb-compatible Thomas Petazzoni
2016-03-19 16:20 ` Arnout Vandecappelle
2016-03-19 18:07 ` Thomas Petazzoni
2016-03-20 19:39 ` Arnout Vandecappelle
2016-03-18 21:08 ` [Buildroot] [PATCH v2 09/17] uclibc: NPTL thread implementation only available on MMU platforms Thomas Petazzoni
2016-03-18 21:08 ` [Buildroot] [PATCH v2 10/17] musl: build broken on Thumb, use ARM mode Thomas Petazzoni
2016-03-18 21:08 ` [Buildroot] [PATCH v2 11/17] toolchain-buildroot: update glibc comment for noMMU Thomas Petazzoni
2016-03-18 21:08 ` [Buildroot] [PATCH v2 12/17] toolchain-buildroot: don't show musl on noMMU platforms Thomas Petazzoni
2016-03-18 21:08 ` [Buildroot] [PATCH v2 13/17] package/Makefile.in: adjust LDFLAGS for elf2flt Thomas Petazzoni
2016-03-18 21:08 ` [Buildroot] [PATCH v2 14/17] elf2flt: use new upstream site and add ARM patch Thomas Petazzoni
2016-03-18 21:34 ` Ezequiel Garcia
2016-03-19 13:32 ` Thomas Petazzoni
2016-03-18 21:08 ` [Buildroot] [PATCH v2 15/17] afboot-stm32: use the Buildroot toolchain Thomas Petazzoni
2016-03-18 21:08 ` [Buildroot] [PATCH v2 16/17] configs/stm32f429_disco: new configuration for STM32F429 Discovery board Thomas Petazzoni
2016-03-21 9:48 ` Lee Jones
2016-03-21 10:39 ` Thomas Petazzoni
2016-03-18 21:08 ` [Buildroot] [PATCH v2 17/17] configs/stm32f469_disco: new configuration for STM32F469 " Thomas Petazzoni
2016-03-21 9:46 ` Lee Jones
2016-03-18 21:17 ` [Buildroot] [PATCH v2 00/17] ARM Cortex-M support and STM32 defconfigs Thomas Petazzoni
2016-03-18 22:49 ` Ezequiel Garcia
2016-03-19 13:32 ` Thomas Petazzoni
2016-03-19 16:12 ` Arnout Vandecappelle
2016-03-20 14:39 ` Thomas Petazzoni
2016-03-21 9:49 ` Lee Jones
2016-03-29 22:28 ` Thomas Petazzoni
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