1 # Target definition: architecture, optimisations, etc...
12 # Pre-declare target optimisation variables
13 config ARCH_SUPPORT_ARCH
14 config ARCH_SUPPORT_ABI
15 config ARCH_SUPPORT_CPU
16 config ARCH_SUPPORT_TUNE
17 config ARCH_SUPPORT_FPU
18 config ARCH_SUPPORTS_BOTH_ENDIAN
19 config ARCH_DEFAULT_BE
20 config ARCH_DEFAULT_LE
33 comment "General target options"
35 source config.gen/arch.in
37 config ARCH_SUPPORTS_BOTH_ENDIAN
41 config ARCH_DEFAULT_BE
45 config ARCH_DEFAULT_LE
52 depends on ARCH_SUPPORTS_BOTH_ENDIAN
53 default ARCH_BE if ARCH_DEFAULT_BE
54 default ARCH_LE if ARCH_DEFAULT_LE
62 prompt "Little endian"
66 comment "Target optimisations"
68 config ARCH_SUPPORT_ARCH
72 config ARCH_SUPPORT_ABI
76 config ARCH_SUPPORT_CPU
80 config ARCH_SUPPORT_TUNE
84 config ARCH_SUPPORT_FPU
90 prompt "Architecture level"
91 depends on ARCH_SUPPORT_ARCH
94 GCC uses this name to determine what kind of instructions it can emit
95 when generating assembly code. This option can be used in conjunction
96 with or instead of the ARCH_CPU option (above), or a (command-line)
99 This is the configuration flag --with-arch=XXXX, and the runtime flag
102 Pick a value from the gcc manual for your choosen gcc version and your
105 Leave blank if you don't know, or if your target architecture does not
110 prompt "Generate code for the specific ABI"
111 depends on ARCH_SUPPORT_ABI
114 Generate code for the given ABI.
116 This is the configuration flag --with-abi=XXXX, and the runtime flag
119 Pick a value from the gcc manual for your choosen gcc version and your
122 Leave blank if you don't know, or if your target architecutre does not
127 prompt "Emit assembly for CPU"
128 depends on ARCH_SUPPORT_CPU
131 This specifies the name of the target processor. GCC uses this name
132 to determine what kind of instructions it can emit when generating
135 This is the configuration flag --with-cpu=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 "Tune for CPU"
147 depends on ARCH_SUPPORT_TUNE
150 This option is very similar to the ARCH_CPU option (above), except
151 that instead of specifying the actual target processor type, and hence
152 restricting which instructions can be used, it specifies that GCC should
153 tune the performance of the code as if the target were of the type
154 specified in this option, but still choosing the instructions that it
155 will generate based on the cpu specified by the ARCH_CPU option
156 (above), or a (command-line) -mcpu= option.
158 This is the configuration flag --with-tune=XXXX, and the runtime flag
161 Pick a value from the gcc manual for your choosen gcc version and your
164 Leave blank if you don't know, or if your target architecture does not
169 prompt "Use specific FPU"
170 depends on ARCH_SUPPORT_FPU
173 On some targets (eg. ARM), you can specify the kind of FPU to emit
176 This is the configuration flag --with-fpu=XXX, and the runtime flag
179 See below wether to actually emit FP opcodes, or to emulate them.
181 Pick a value from the gcc manual for your choosen gcc version and your
184 Leave blank if you don't know, or if your target architecture does not
189 prompt "Floating point:"
193 prompt "hardware (FPU)"
195 Emit hardware floating point opcodes.
197 If you've got a processor with a FPU, then you want that.
198 If your hardware has no FPU, you still can use HW floating point, but
199 need to compile support for FPU emulation in your kernel. Needless to
200 say that emulating the FPU is /slooowwwww/...
202 One situation you'd want HW floating point without a FPU is if you get
203 binary blobs from different vendors that are compiling this way and
204 can't (don't wan't to) change.
210 Do not emit any hardware floating point opcode.
212 If your processor has no FPU, then you most probably want this, as it
213 is faster than emulating the FPU in the kernel.
219 prompt "Target CFLAGS"
222 Used to add specific options when compiling libraries of the toolchain,
223 that will run on the target (eg. libc.so).
225 Note that the options above for ARCH, ABI, CPU, TUNE and FPU will be
226 automaticaly used. You don't need to specify them here.
228 Leave blank if you don't know better.
230 config TARGET_LDFLAGS
232 prompt "Target LDFLAGS"
235 Used to add specific options when linking libraries of the toolchain,
236 that will run on your target.
238 Leave blank if you don't know better.