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_BOTH_ENDIAN
27 select ARCH_SUPPORTS_BOTH_ENDIAN
39 config ARCH_SUPPORTS_BOTH_ENDIAN
46 depends on ARCH_SUPPORTS_BOTH_ENDIAN
54 prompt "Little endian"
58 comment "Target optimisations"
62 prompt "Achitecture level"
65 GCC uses this name to determine what kind of instructions it can emit
66 when generating assembly code. This option can be used in conjunction
67 with or instead of the ARCH_CPU option (above), or a (command-line)
70 This is the configuration flag --with-arch=XXXX, and the runtime flag
73 Pick a value from the gcc manual for your choosen gcc version and your
76 Leave blank if you don't know, or if your target architecture does not
81 prompt "Generate code for the specific ABI"
84 Generate code for the given ABI.
86 This is the configuration flag --with-abi=XXXX, and the runtime flag
89 Pick a value from the gcc manual for your choosen gcc version and your
92 Leave blank if you don't know, or if your target architecutre does not
97 prompt "Emit assembly for CPU"
100 This specifies the name of the target processor. GCC uses this name
101 to determine what kind of instructions it can emit when generating
104 This is the configuration flag --with-cpu=XXXX, and the runtime flag
107 Pick a value from the gcc manual for your choosen gcc version and your
110 Leave blank if you don't know, or if your target architecture does not
115 prompt "Tune for CPU"
118 This option is very similar to the ARCH_CPU option (above), except
119 that instead of specifying the actual target processor type, and hence
120 restricting which instructions can be used, it specifies that GCC should
121 tune the performance of the code as if the target were of the type
122 specified in this option, but still choosing the instructions that it
123 will generate based on the cpu specified by the ARCH_CPU option
124 (above), or a (command-line) -mcpu= option.
126 This is the configuration flag --with-tune=XXXX, and the runtime flag
129 Pick a value from the gcc manual for your choosen gcc version and your
132 Leave blank if you don't know, or if your target architecture does not
137 prompt "Use specific FPU"
140 On some targets (eg. ARM), you can specify the kind of FPU to emit
143 This is the configuration flag --with-fpu=XXX, and the runtime flag
146 See below wether to actually emit FP opcodes, or to emulate them.
148 Pick a value from the gcc manual for your choosen gcc version and your
151 Leave blank if you don't know, or if your target architecture does not
156 prompt "Floating point:"
160 prompt "hardware (FPU)"
162 Emit hardware floating point opcodes.
164 If you've got a processor with a FPU, then you want that.
165 If your hardware has no FPU, you still can use HW floating point, but
166 need to compile support for FPU emulation in your kernel. Needless to
167 say that emulating the FPU is /slooowwwww/...
169 One situation you'd want HW floating point without a FPU is if you get
170 binary blobs from different vendors that are compiling this way and
171 can't (don't wan't to) change.
177 Do not emit any hardware floating point opcode.
179 If your processor has no FPU, then you most probably want this, as it
180 is faster than emulating the FPU in the kernel.
186 prompt "Target CFLAGS"
189 Used to add specific options when compiling libraries of the toolchain,
190 that will run on the target (eg. libc.so).
192 Note that the options above for CPU, tune, arch and FPU will be
193 automaticaly used. You don't need to specify them here.
195 Leave blank if you don't know better.