1 # Target definition: architecture, optimisations, etc...
5 comment "General target options"
9 default "arm" if ARCH_ARM
10 default "mips" if ARCH_MIPS
11 default "x86" if ARCH_x86
12 default "x86_64" if ARCH_x86_64
16 prompt "Target architecture:"
22 select ARCH_SUPPORTS_BE
23 select ARCH_SUPPORTS_LE
28 select ARCH_SUPPORTS_BE
29 select ARCH_SUPPORTS_LE
34 select ARCH_SUPPORTS_LE
39 select ARCH_SUPPORTS_LE
43 config ARCH_SUPPORTS_BE
47 config ARCH_SUPPORTS_LE
58 depends on ARCH_SUPPORTS_BE
62 prompt "Little endian"
63 depends on ARCH_SUPPORTS_LE
67 comment "Target optimisations"
71 prompt "Achitecture level"
74 GCC uses this name to determine what kind of instructions it can emit
75 when generating assembly code. This option can be used in conjunction
76 with or instead of the ARCH_CPU option (above), or a (command-line)
79 This is the configuration flag --with-arch=XXXX, and the runtime flag
82 Pick a value from the gcc manual for your choosen gcc version and your
85 Leave blank if you don't know, or if your target architecture does not
90 prompt "Generate code for the specific ABI"
93 Generate code for the given ABI.
95 This is the configuration flag --with-abi=XXXX, and the runtime flag
98 Pick a value from the gcc manual for your choosen gcc version and your
101 Leave blank if you don't know, or if your target architecutre does not
106 prompt "Emit assembly for CPU"
109 This specifies the name of the target ARM processor. GCC uses this name
110 to determine what kind of instructions it can emit when generating
113 This is the configuration flag --with-cpu=XXXX, and the runtime flag
116 Pick a value from the gcc manual for your choosen gcc version and your
119 Leave blank if you don't know, or if your target architecture does not
124 prompt "Tune for CPU"
127 This option is very similar to the ARCH_CPU option (above), except
128 that instead of specifying the actual target processor type, and hence
129 restricting which instructions can be used, it specifies that GCC should
130 tune the performance of the code as if the target were of the type
131 specified in this option, but still choosing the instructions that it
132 will generate based on the cpu specified by the ARCH_CPU option
133 (above), or a (command-line) -mcpu= option.
135 This is the configuration flag --with-tune=XXXX, and the runtime flag
138 Pick a value from the gcc manual for your choosen gcc version and your
141 Leave blank if you don't know, or if your target architecture does not
146 prompt "Use specific FPU"
149 On some targets (eg. ARM), you can specify the kind of FPU to emit
152 This is the configuration flag --with-fpu=XXX, and the runtime flag
155 See below wether to actually emit FP opcodes, or to emulate them.
157 Pick a value from the gcc manual for your choosen gcc version and your
160 Leave blank if you don't know, or if your target architecture does not
165 prompt "Floating point:"
169 prompt "hardware (FPU)"
171 Emit hardware floating point opcodes.
173 If you've got a processor with a FPU, then you want that.
174 If your hardware has no FPU, you still can use HW floating point, but
175 need to compile support for FPU emulation in your kernel. Needless to
176 say that emulating the FPU is /slooowwwww/...
178 One situation you'd want HW floating point without a FPU is if you get
179 binary blobs from different vendors that are compiling this way and
180 can't (don't wan't to) change.
186 Do not emit any hardware floating point opcode.
188 If your processor has no FPU, then you most probably want this, as it
189 is faster than emulating the FPU in the kernel.
193 config ARCH_FLOAT_SW_LIBFLOAT
195 prompt "Use libfloat"
197 depends on ARCH_FLOAT_SW
199 For those targets upporting it, you can use libfloat for the software
200 floating point emulation.
202 Note that some versions of gcc have support code that supersedes libfloat,
203 while others don't. Known version of gcc that don't have support code are
204 versions prior to 3.0, and version above 4.0.
206 You should check gcc before deciding to use libfloat.
208 config LIBFLOAT_VERSION
210 default "990616.orig"
211 depends on ARCH_FLOAT_SW_LIBFLOAT
215 prompt "Target CFLAGS"
218 Used to add specific options when compiling libraries of the toolchain,
219 that will run on the target (eg. libc.so).
221 Note that the options above for CPU, tune, arch and FPU will be
222 automaticaly used. You don't need to specify them here.
224 Leave blank if you don't know better.