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Thomas Petazzoni 85d0769ac5 arch/arm: add support for Thumb2
Until now, we were using the default ARM instruction set, as used by
the toolchain: the 32 bits ARM instruction set for the internal
backend, and for external toolchain, whatever default was chosen when
the toolchain was generated.

This commit adds support for the Thumb2 instruction set. To do so, it:

 * provides a menuconfig choice between ARM and Thumb2. The choice is
   only shown when Thumb2 is supported, i.e on ARMv7-A CPUs.

 * passes the --with-mode={arm,thumb} option when building gcc in the
   internal backend. This tells the compiler which type of
   instructions it should generate.

 * passes the m{arm,thumb} option in the external toolchain
   wrapper. ARM and Thumb2 code can freely be mixed together, so the
   fact that the C library has been built either ARM or Thumb2 and
   that the rest of the code is built Thumb2 or ARM is not a problem.

[Peter: fix empty BR2_GCC_TARGET_MODE check]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2013-07-16 15:28:03 +02:00
arch arch/arm: add support for Thumb2 2013-07-16 15:28:03 +02:00
board
boot
configs configs: update defconfigs after VFP option changes 2013-07-16 15:14:53 +02:00
docs
fs
linux linux: remove EABI conditional 2013-07-14 22:16:40 +02:00
package arch/arm: add support for Thumb2 2013-07-16 15:28:03 +02:00
support
system
toolchain arch/arm: add support for Thumb2 2013-07-16 15:28:03 +02:00
.defconfig
.gitignore
CHANGES
Config.in
Config.in.legacy toolchain: remove the old BR2_VFP_FLOAT option 2013-07-16 15:13:57 +02:00
COPYING
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Makefile.legacy

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