config/target.in
author "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
Tue May 22 20:36:44 2007 +0000 (2007-05-22)
changeset 117 80c4338ec0a0
parent 108 69407950a2a2
child 136 22b5ef41df97
permissions -rw-r--r--
Only prompt for libfloat for those target that support it.
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# Target definition: architecture, optimisations, etc...
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menu "Target options"
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comment "General target options"
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config ARCH
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    string
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    default "arm"     if ARCH_ARM
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    default "mips"    if ARCH_MIPS
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    default "x86"     if ARCH_x86
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    default "x86_64"  if ARCH_x86_64
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choice
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    bool
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    prompt "Target architecture:"
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    default ARCH_x86
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config ARCH_ARM
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    bool
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    prompt "arm"
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    select ARCH_SUPPORTS_BE
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    select ARCH_SUPPORTS_LE
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    select ARCH_SUPPORTS_LIBFLOAT
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config ARCH_MIPS
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    bool
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    prompt "mips"
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    select ARCH_SUPPORTS_BE
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    select ARCH_SUPPORTS_LE
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config ARCH_x86
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    bool
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    prompt "x86"
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    select ARCH_SUPPORTS_LE
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    select ARCH_SUPPORTS_LIBFLOAT
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config ARCH_x86_64
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    bool
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    prompt "x86_64"
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    select ARCH_SUPPORTS_LE
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endchoice
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config ARCH_SUPPORTS_BE
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    bool
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    default n
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config ARCH_SUPPORTS_LE
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    bool
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    default n
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choice
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    bool
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    prompt "Endianness:"
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config ARCH_BE
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    bool
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    prompt "Big endian"
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    depends on ARCH_SUPPORTS_BE
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config ARCH_LE
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    bool
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    prompt "Little endian"
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    depends on ARCH_SUPPORTS_LE
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endchoice
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comment "Target optimisations"
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config ARCH_ARCH
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    string
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    prompt "Achitecture level"
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    default ""
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    help
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      GCC uses this name to determine what kind of instructions it can emit
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      when generating assembly code. This option can be used in conjunction
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      with or instead of the ARCH_CPU option (above), or a (command-line)
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      -mcpu= option.
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      This is the configuration flag --with-arch=XXXX, and the runtime flag
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      -march=XXX.
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      Pick a value from the gcc manual for your choosen gcc version and your
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      target CPU.
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      Leave blank if you don't know, or if your target architecture does not
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      offer this option.
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config ARCH_ABI
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    string
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    prompt "Generate code for the specific ABI"
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    default ""
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    help
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      Generate code for the given ABI.
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      This is the configuration flag --with-abi=XXXX, and the runtime flag
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      -mabi=XXX.
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      Pick a value from the gcc manual for your choosen gcc version and your
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      target CPU.
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      Leave blank if you don't know, or if your target architecutre does not
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      offer this option.
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config ARCH_CPU
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    string
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    prompt "Emit assembly for CPU"
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    default ""
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    help
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      This specifies the name of the target ARM processor. GCC uses this name
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      to determine what kind of instructions it can emit when generating
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      assembly code.
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      This is the configuration flag --with-cpu=XXXX, and the runtime flag
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      -mcpu=XXX.
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      Pick a value from the gcc manual for your choosen gcc version and your
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      target CPU.
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      Leave blank if you don't know, or if your target architecture does not
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      offer this option.
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config ARCH_TUNE
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    string
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    prompt "Tune for CPU"
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    default ""
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    help
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      This option is very similar to the ARCH_CPU option (above), except
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      that instead of specifying the actual target processor type, and hence
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      restricting which instructions can be used, it specifies that GCC should
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      tune the performance of the code as if the target were of the type
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      specified in this option, but still choosing the instructions that it
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      will generate based on the cpu specified by the ARCH_CPU option
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      (above), or a (command-line) -mcpu= option.
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      This is the configuration flag --with-tune=XXXX, and the runtime flag
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      -mtune=XXX.
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      Pick a value from the gcc manual for your choosen gcc version and your
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      target CPU.
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      Leave blank if you don't know, or if your target architecture does not
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      offer this option.
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config ARCH_FPU
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    string
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    prompt "Use specific FPU"
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    default ""
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    help
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      On some targets (eg. ARM), you can specify the kind of FPU to emit
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      code for.
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      This is the configuration flag --with-fpu=XXX, and the runtime flag
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      -mfpu=XXX.
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      See below wether to actually emit FP opcodes, or to emulate them.
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      Pick a value from the gcc manual for your choosen gcc version and your
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      target CPU.
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      Leave blank if you don't know, or if your target architecture does not
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      offer this option.
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choice
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    bool
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    prompt "Floating point:"
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config ARCH_FLOAT_HW
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    bool
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    prompt "hardware (FPU)"
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    help
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      Emit hardware floating point opcodes.
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      If you've got a processor with a FPU, then you want that.
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      If your hardware has no FPU, you still can use HW floating point, but
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      need to compile support for FPU emulation in your kernel. Needless to
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      say that emulating the FPU is /slooowwwww/...
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      One situation you'd want HW floating point without a FPU is if you get
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      binary blobs from different vendors that are compiling this way and
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      can't (don't wan't to) change.
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config ARCH_FLOAT_SW
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    bool
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    prompt "software"
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    help
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      Do not emit any hardware floating point opcode.
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      If your processor has no FPU, then you most probably want this, as it
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      is faster than emulating the FPU in the kernel.
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endchoice
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config ARCH_SUPPORTS_LIBFLOAT
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    bool
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    default n
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config ARCH_FLOAT_SW_LIBFLOAT
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    bool
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    prompt "Use libfloat"
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    default n
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    depends on ARCH_FLOAT_SW && ARCH_SUPPORTS_LIBFLOAT
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    help
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      For those targets upporting it, you can use libfloat for the software
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      floating point emulation.
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      Note that some versions of gcc have support code that supersedes libfloat,
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      while others don't. Known version of gcc that don't have support code are
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      versions prior to 3.0, and version above 4.0.
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      You should check gcc before deciding to use libfloat.
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config LIBFLOAT_VERSION
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    string
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    default "990616.orig"
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    depends on ARCH_FLOAT_SW_LIBFLOAT
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config TARGET_CFLAGS
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    string
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    prompt "Target CFLAGS"
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    default ""
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    help
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      Used to add specific options when compiling libraries of the toolchain,
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      that will run on the target (eg. libc.so).
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      Note that the options above for CPU, tune, arch and FPU will be
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      automaticaly used. You don't need to specify them here.
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      Leave blank if you don't know better.
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endmenu