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Thomas Petazzoni 8e55f03a54 Clarify MIPS ABIs support
Practically speaking, MIPS has three useful ABIs:

 * o32 is for 32-bits CPUs, or 64-bit CPUs running only a 32-bit subset
   of the instruction set.
 * n32 is for 64-bits CPUs only. It has 32-bits pointers and long
   integers.
 * n64 is for 64-bits CPUs only. It has 64-bits pointers and long
   integers.

See http://www.linux-mips.org/wiki/MIPS_ABI_History and
http://www.linux-mips.org/wiki/WhatsWrongWithO32N32N64 for more
details.

So, this commit reworks the Buildroot MIPS support by:

 * Add separate mips64/mips64el top-level architectures.

 * Renaming the n32 ABI option to BR2_MIPS_NABI32, for consistency
   with BR2_MIPS_OABI32.

 * Renaming the n64 ABI option to BR2_MIPS_NABI64, for consistency
   with BR2_MIPS_OABI32.

 * Make the n32 and n64 ABI selections select the BR2_ARCH_IS_64,
   since those ABIs are valid on 64-bits CPUs only.

 * Removing the o64 ABI, which is practicaly never used.

 * Removing the "none" ABI, which really doesn't make sense.

 * Introduce the mips64 and mips64el architecture names when a 64-bits
   MIPS ABI is choosen. This will fix build issue like
   http://autobuild.buildroot.org/results/9b8c5ea86c953a89e85e7b67e9221de41773f652/build-end.log
   where gmp was confused by the fact of having a 32 bits architecture
   (detected by the mips- architecture part of the tuple) but 64 bits
   integer size when compiling.

 * Adjust the uclibc.mk logic to support the new mips64/mips64el
   architecture names, and take into account the renaming of the ABI
   options.

This has been build tested by generating Buildroot toolchains and
compiling a few packages for MIPS o32, MIPS n32 and MIPS n64.

This work is originally based on prior work done by Gustavo Zacarias.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2012-09-04 22:03:55 +02:00
board Add support for the Calao-systems QIL-A9260 2012-08-11 23:17:49 +02:00
boot Merge branch 'next' 2012-09-03 21:59:03 +02:00
configs Add support for the Calao-systems QIL-A9260 2012-08-11 23:17:49 +02:00
docs Prepare for 2012.08 2012-08-31 10:49:41 +02:00
fs Add the www-data user group to the skeleton target filesystem 2012-04-26 15:22:15 +02:00
linux linux: bump default to kernel version 3.5.3 2012-09-04 15:50:21 +02:00
package Clarify MIPS ABIs support 2012-09-04 22:03:55 +02:00
support support/graph-depends: fix out-of-tree usage 2012-08-14 15:09:21 +02:00
target Clarify MIPS ABIs support 2012-09-04 22:03:55 +02:00
toolchain Clarify MIPS ABIs support 2012-09-04 22:03:55 +02:00
.defconfig buildroot: get rid of s390 support 2009-01-12 14:36:14 +00:00
.gitignore .gitignore: ignore more patch related files 2010-11-18 12:07:23 +01:00
CHANGES Kickoff 2012.11 cycle 2012-09-03 21:27:41 +02:00
Config.in Remove BR2_SOURCEFORGE_MIRROR variable 2012-08-29 01:04:58 +02:00
COPYING clarify license and fix website license link 2009-05-08 09:29:41 +02:00
Makefile Kickoff 2012.11 cycle 2012-09-03 21:27:41 +02:00

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