yann@1
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1 |
# Target definition: architecture, optimisations, etc...
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yann@1
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2 |
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yann@1
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3 |
menu "Target options"
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yann@1
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4 |
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yann@47
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5 |
config ARCH
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yann@47
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6 |
string
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yann@628
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7 |
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yann@628
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8 |
# Pre-declare target optimisation variables
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yann@1345
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9 |
config ARCH_SUPPORTS_BOTH_MMU
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yann@1345
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10 |
config ARCH_SUPPORTS_BOTH_ENDIAN
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yann@1633
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11 |
config ARCH_SUPPORTS_32
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yann@1633
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12 |
config ARCH_SUPPORTS_64
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yann@2788
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13 |
config ARCH_SUPPORTS_WITH_ARCH
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yann@2788
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14 |
config ARCH_SUPPORTS_WITH_ABI
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yann@2788
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15 |
config ARCH_SUPPORTS_WITH_CPU
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yann@2788
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16 |
config ARCH_SUPPORTS_WITH_TUNE
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yann@2789
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17 |
config ARCH_SUPPORTS_WITH_FLOAT
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yann@2788
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18 |
config ARCH_SUPPORTS_WITH_FPU
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yann@2788
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19 |
config ARCH_SUPPORTS_SOFTFP
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yann@1345
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20 |
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yann@1345
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21 |
config ARCH_DEFAULT_HAS_MMU
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yann@628
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22 |
config ARCH_DEFAULT_BE
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yann@628
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23 |
config ARCH_DEFAULT_LE
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yann@1633
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24 |
config ARCH_DEFAULT_32
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yann@1633
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25 |
config ARCH_DEFAULT_64
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yann@1345
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26 |
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yann@633
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27 |
config ARCH_ARCH
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yann@633
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28 |
config ARCH_ABI
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yann@633
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29 |
config ARCH_CPU
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yann@633
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30 |
config ARCH_TUNE
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yann@633
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31 |
config ARCH_FPU
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yann@633
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32 |
config ARCH_BE
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yann@633
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33 |
config ARCH_LE
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yann@1638
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34 |
config ARCH_32
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yann@1638
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config ARCH_64
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yann@1715
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36 |
config ARCH_BITNESS
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yann@628
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37 |
config ARCH_FLOAT_HW
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yann@628
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config ARCH_FLOAT_SW
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yann@628
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config TARGET_CFLAGS
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yann@791
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config TARGET_LDFLAGS
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yann@628
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41 |
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yann@1870
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source "config.gen/arch.in"
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yann@1
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43 |
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yann@1345
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#--------------------------------------
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yann@2413
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comment "Generic target options"
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yann@2413
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46 |
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yann@2815
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#--------------------------------------
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yann@2815
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48 |
config MULTILIB
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yann@2815
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bool
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yann@2815
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prompt "Build a multilib toolchain (EXPERIMENTAL)"
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yann@2815
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51 |
depends on EXPERIMENTAL
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yann@2815
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help
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yann@2815
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If you say 'y' here, then the toolchain will also contain the C library
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yann@2815
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54 |
optimised for some variants of the selected architecture, besides the
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yann@2815
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default settings.
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yann@2815
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56 |
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yann@2815
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57 |
This means the build time of the C library will be in O(nb_variants).
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yann@2815
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58 |
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yann@2815
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59 |
The list of variants is dependent on the architecture, and is hard-coded
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yann@2815
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60 |
in gcc, so it is not possible to say what variants to support, only
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yann@2815
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61 |
whether hard-coded variants should be supported or not.
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yann@2815
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62 |
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yann@2815
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63 |
#--------------------------------------
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yann@1345
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64 |
config ARCH_SUPPORTS_BOTH_MMU
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yann@1345
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bool
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yann@1345
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66 |
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yann@1345
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67 |
config ARCH_DEFAULT_HAS_MMU
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yann@1345
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68 |
bool
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yann@1345
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69 |
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yann@1345
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70 |
config ARCH_USE_MMU
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yann@1345
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71 |
bool
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yann@1345
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72 |
prompt "Use the MMU" if ARCH_SUPPORTS_BOTH_MMU
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yann@1345
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default y if ARCH_DEFAULT_HAS_MMU
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yann@1586
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74 |
help
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yann@1586
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75 |
If your architecture has an MMU and you want to use it,
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yann@1586
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76 |
say 'Y' here.
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yann@1586
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77 |
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yann@1586
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78 |
OTOH, if you don't want to use the MMU, or your arch
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yann@1586
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79 |
lacks an MMU, say 'N' here.
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yann@1586
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80 |
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yann@1586
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81 |
Note that some architectures (eg. ARM) has variants that
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yann@1586
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82 |
lacks an MMU (eg. ARM Cortex-M3), while other variants
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yann@1586
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83 |
have one (eg. ARM Cortex-A8).
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yann@1345
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84 |
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yann@1345
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85 |
#--------------------------------------
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yann@136
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86 |
config ARCH_SUPPORTS_BOTH_ENDIAN
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yann@35
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bool
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yann@35
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88 |
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yann@347
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89 |
config ARCH_DEFAULT_BE
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yann@347
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90 |
bool
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yann@347
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91 |
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yann@347
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92 |
config ARCH_DEFAULT_LE
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yann@347
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93 |
bool
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yann@347
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94 |
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yann@1
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95 |
choice
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yann@1
|
96 |
bool
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yann@1
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97 |
prompt "Endianness:"
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yann@136
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98 |
depends on ARCH_SUPPORTS_BOTH_ENDIAN
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yann@347
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99 |
default ARCH_BE if ARCH_DEFAULT_BE
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yann@347
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100 |
default ARCH_LE if ARCH_DEFAULT_LE
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yann@1
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101 |
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yann@1
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102 |
config ARCH_BE
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yann@1
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103 |
bool
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yann@1
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104 |
prompt "Big endian"
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yann@1
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105 |
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yann@1
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106 |
config ARCH_LE
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yann@1
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107 |
bool
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yann@1
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108 |
prompt "Little endian"
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yann@1
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109 |
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yann@1
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110 |
endchoice
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yann@1
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111 |
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yann@2772
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112 |
config ARCH_ENDIAN
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yann@2772
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113 |
string
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yann@2772
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114 |
depends on ARCH_SUPPORTS_BOTH_ENDIAN
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yann@2772
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115 |
default "big" if ARCH_BE
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yann@2772
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116 |
default "little" if ARCH_LE
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yann@2772
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117 |
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yann@1345
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118 |
#--------------------------------------
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yann@1633
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119 |
config ARCH_SUPPORTS_32
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yann@1633
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120 |
bool
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yann@1633
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121 |
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yann@1633
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122 |
config ARCH_SUPPORTS_64
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yann@1633
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123 |
bool
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yann@1633
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124 |
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yann@1633
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125 |
config ARCH_DEFAULT_32
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yann@1633
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126 |
bool
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yann@1633
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127 |
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yann@1633
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128 |
config ARCH_DEFAULT_64
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yann@1633
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129 |
bool
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yann@1633
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130 |
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yann@1715
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131 |
config ARCH_BITNESS
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yann@1715
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132 |
int
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yann@1715
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133 |
default "32" if ARCH_32
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yann@1715
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134 |
default "64" if ARCH_64
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yann@1715
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135 |
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yann@1633
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136 |
choice
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yann@1633
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137 |
bool
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yann@1633
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138 |
prompt "Bitness:"
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yann@1638
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139 |
default ARCH_32 if ARCH_DEFAULT_32
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yann@1638
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140 |
default ARCH_64 if ARCH_DEFAULT_64
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yann@1633
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141 |
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yann@1638
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142 |
config ARCH_32
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yann@1633
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143 |
bool
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yann@1633
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144 |
prompt "32-bit"
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yann@1633
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145 |
depends on ARCH_SUPPORTS_32
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yann@1633
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146 |
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yann@1638
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147 |
config ARCH_64
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yann@1633
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148 |
bool
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yann@1633
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149 |
prompt "64-bit"
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yann@1633
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150 |
depends on ARCH_SUPPORTS_64
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yann@1633
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151 |
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yann@1633
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152 |
endchoice
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yann@1633
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153 |
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yann@1633
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154 |
#--------------------------------------
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yann@1
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155 |
comment "Target optimisations"
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yann@1
|
156 |
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yann@2788
|
157 |
config ARCH_SUPPORTS_WITH_ARCH
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yann@631
|
158 |
bool
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yann@631
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159 |
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yann@2788
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160 |
config ARCH_SUPPORTS_WITH_ABI
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yann@631
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161 |
bool
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yann@631
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162 |
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yann@2788
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163 |
config ARCH_SUPPORTS_WITH_CPU
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yann@631
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164 |
bool
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yann@631
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165 |
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yann@2788
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166 |
config ARCH_SUPPORTS_WITH_TUNE
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yann@631
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167 |
bool
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yann@631
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168 |
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yann@2789
|
169 |
config ARCH_SUPPORTS_WITH_FLOAT
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yann@2789
|
170 |
bool
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yann@2789
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171 |
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yann@2788
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172 |
config ARCH_SUPPORTS_WITH_FPU
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yann@631
|
173 |
bool
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yann@631
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174 |
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yann@2788
|
175 |
config ARCH_SUPPORTS_SOFTFP
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michael@2739
|
176 |
bool
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michael@2739
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177 |
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yann@47
|
178 |
config ARCH_ARCH
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yann@47
|
179 |
string
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yann@425
|
180 |
prompt "Architecture level"
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yann@2788
|
181 |
depends on ARCH_SUPPORTS_WITH_ARCH
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yann@47
|
182 |
default ""
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yann@47
|
183 |
help
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yann@47
|
184 |
GCC uses this name to determine what kind of instructions it can emit
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yann@47
|
185 |
when generating assembly code. This option can be used in conjunction
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yann@47
|
186 |
with or instead of the ARCH_CPU option (above), or a (command-line)
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yann@47
|
187 |
-mcpu= option.
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yann@47
|
188 |
|
yann@47
|
189 |
This is the configuration flag --with-arch=XXXX, and the runtime flag
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yann@47
|
190 |
-march=XXX.
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yann@47
|
191 |
|
yann@47
|
192 |
Pick a value from the gcc manual for your choosen gcc version and your
|
yann@47
|
193 |
target CPU.
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yann@47
|
194 |
|
yann@47
|
195 |
Leave blank if you don't know, or if your target architecture does not
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yann@47
|
196 |
offer this option.
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yann@47
|
197 |
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yann@45
|
198 |
config ARCH_ABI
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yann@45
|
199 |
string
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yann@45
|
200 |
prompt "Generate code for the specific ABI"
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yann@2788
|
201 |
depends on ARCH_SUPPORTS_WITH_ABI
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yann@45
|
202 |
default ""
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yann@45
|
203 |
help
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yann@45
|
204 |
Generate code for the given ABI.
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yann@45
|
205 |
|
yann@47
|
206 |
This is the configuration flag --with-abi=XXXX, and the runtime flag
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yann@47
|
207 |
-mabi=XXX.
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yann@47
|
208 |
|
yann@45
|
209 |
Pick a value from the gcc manual for your choosen gcc version and your
|
yann@45
|
210 |
target CPU.
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yann@45
|
211 |
|
antony@2564
|
212 |
Leave blank if you don't know, or if your target architecture does not
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yann@45
|
213 |
offer this option.
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yann@45
|
214 |
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yann@1
|
215 |
config ARCH_CPU
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yann@1
|
216 |
string
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yann@1
|
217 |
prompt "Emit assembly for CPU"
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yann@2788
|
218 |
depends on ARCH_SUPPORTS_WITH_CPU
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yann@1
|
219 |
default ""
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yann@1
|
220 |
help
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yann@283
|
221 |
This specifies the name of the target processor. GCC uses this name
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yann@1
|
222 |
to determine what kind of instructions it can emit when generating
|
yann@1
|
223 |
assembly code.
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yann@1
|
224 |
|
yann@47
|
225 |
This is the configuration flag --with-cpu=XXXX, and the runtime flag
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yann@47
|
226 |
-mcpu=XXX.
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yann@47
|
227 |
|
yann@1
|
228 |
Pick a value from the gcc manual for your choosen gcc version and your
|
yann@1
|
229 |
target CPU.
|
yann@1
|
230 |
|
yann@1
|
231 |
Leave blank if you don't know, or if your target architecture does not
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yann@1
|
232 |
offer this option.
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yann@1
|
233 |
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yann@1
|
234 |
config ARCH_TUNE
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yann@1
|
235 |
string
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yann@1
|
236 |
prompt "Tune for CPU"
|
yann@2788
|
237 |
depends on ARCH_SUPPORTS_WITH_TUNE
|
yann@1
|
238 |
default ""
|
yann@1
|
239 |
help
|
yann@1
|
240 |
This option is very similar to the ARCH_CPU option (above), except
|
yann@1
|
241 |
that instead of specifying the actual target processor type, and hence
|
yann@1
|
242 |
restricting which instructions can be used, it specifies that GCC should
|
yann@1
|
243 |
tune the performance of the code as if the target were of the type
|
yann@1
|
244 |
specified in this option, but still choosing the instructions that it
|
yann@1
|
245 |
will generate based on the cpu specified by the ARCH_CPU option
|
yann@1
|
246 |
(above), or a (command-line) -mcpu= option.
|
yann@1
|
247 |
|
yann@47
|
248 |
This is the configuration flag --with-tune=XXXX, and the runtime flag
|
yann@47
|
249 |
-mtune=XXX.
|
yann@1
|
250 |
|
yann@1
|
251 |
Pick a value from the gcc manual for your choosen gcc version and your
|
yann@1
|
252 |
target CPU.
|
yann@1
|
253 |
|
yann@1
|
254 |
Leave blank if you don't know, or if your target architecture does not
|
yann@1
|
255 |
offer this option.
|
yann@1
|
256 |
|
yann@1
|
257 |
config ARCH_FPU
|
yann@1
|
258 |
string
|
yann@47
|
259 |
prompt "Use specific FPU"
|
yann@2788
|
260 |
depends on ARCH_SUPPORTS_WITH_FPU
|
yann@1
|
261 |
default ""
|
yann@1
|
262 |
help
|
yann@1
|
263 |
On some targets (eg. ARM), you can specify the kind of FPU to emit
|
yann@1
|
264 |
code for.
|
yann@47
|
265 |
|
yann@47
|
266 |
This is the configuration flag --with-fpu=XXX, and the runtime flag
|
yann@47
|
267 |
-mfpu=XXX.
|
yann@1
|
268 |
|
yann@1
|
269 |
See below wether to actually emit FP opcodes, or to emulate them.
|
yann@1
|
270 |
|
yann@1
|
271 |
Pick a value from the gcc manual for your choosen gcc version and your
|
yann@1
|
272 |
target CPU.
|
yann@1
|
273 |
|
yann@1
|
274 |
Leave blank if you don't know, or if your target architecture does not
|
yann@1
|
275 |
offer this option.
|
yann@1
|
276 |
|
yann@1
|
277 |
choice
|
yann@1
|
278 |
bool
|
yann@1
|
279 |
prompt "Floating point:"
|
yann@2794
|
280 |
depends on ARCH_SUPPORTS_WITH_FLOAT
|
yann@1
|
281 |
|
yann@1
|
282 |
config ARCH_FLOAT_HW
|
yann@1
|
283 |
bool
|
yann@1
|
284 |
prompt "hardware (FPU)"
|
yann@1
|
285 |
help
|
yann@1
|
286 |
Emit hardware floating point opcodes.
|
yann@1
|
287 |
|
yann@1
|
288 |
If you've got a processor with a FPU, then you want that.
|
yann@1
|
289 |
If your hardware has no FPU, you still can use HW floating point, but
|
yann@1
|
290 |
need to compile support for FPU emulation in your kernel. Needless to
|
yann@1
|
291 |
say that emulating the FPU is /slooowwwww/...
|
yann@1
|
292 |
|
yann@1
|
293 |
One situation you'd want HW floating point without a FPU is if you get
|
yann@1
|
294 |
binary blobs from different vendors that are compiling this way and
|
yann@1
|
295 |
can't (don't wan't to) change.
|
yann@1
|
296 |
|
yann@1
|
297 |
config ARCH_FLOAT_SW
|
yann@1
|
298 |
bool
|
yann@1
|
299 |
prompt "software"
|
yann@1
|
300 |
help
|
yann@1
|
301 |
Do not emit any hardware floating point opcode.
|
yann@1
|
302 |
|
yann@1
|
303 |
If your processor has no FPU, then you most probably want this, as it
|
yann@1
|
304 |
is faster than emulating the FPU in the kernel.
|
yann@1
|
305 |
|
michael@2739
|
306 |
config ARCH_FLOAT_SOFTFP
|
michael@2739
|
307 |
bool
|
michael@2739
|
308 |
prompt "softfp"
|
yann@2788
|
309 |
depends on ARCH_SUPPORTS_SOFTFP
|
michael@2739
|
310 |
help
|
michael@2739
|
311 |
Emit hardware floating point opcodes but use the software
|
michael@2739
|
312 |
floating point calling convention.
|
michael@2739
|
313 |
|
michael@2739
|
314 |
Architectures such as ARM use different registers for passing
|
michael@2739
|
315 |
floating point values depending on if they're in software mode
|
michael@2739
|
316 |
or hardware mode. softfp emits FPU instructions but uses the
|
michael@2739
|
317 |
software FP calling convention allowing softfp code to
|
michael@2739
|
318 |
interoperate with legacy software only code.
|
michael@2739
|
319 |
|
michael@2739
|
320 |
If in doubt, use 'software' or 'hardware' mode instead.
|
michael@2739
|
321 |
|
yann@1
|
322 |
endchoice
|
yann@1
|
323 |
|
yann@1
|
324 |
config TARGET_CFLAGS
|
yann@1
|
325 |
string
|
yann@41
|
326 |
prompt "Target CFLAGS"
|
yann@1
|
327 |
default ""
|
yann@1
|
328 |
help
|
yann@1
|
329 |
Used to add specific options when compiling libraries of the toolchain,
|
yann@1
|
330 |
that will run on the target (eg. libc.so).
|
yann@1
|
331 |
|
yann@531
|
332 |
Note that the options above for ARCH, ABI, CPU, TUNE and FPU will be
|
antony@2564
|
333 |
automatically used. You don't need to specify them here.
|
yann@1
|
334 |
|
yann@1
|
335 |
Leave blank if you don't know better.
|
yann@1
|
336 |
|
yann@767
|
337 |
config TARGET_LDFLAGS
|
yann@767
|
338 |
string
|
yann@767
|
339 |
prompt "Target LDFLAGS"
|
yann@767
|
340 |
default ""
|
yann@767
|
341 |
help
|
yann@767
|
342 |
Used to add specific options when linking libraries of the toolchain,
|
yann@767
|
343 |
that will run on your target.
|
yann@767
|
344 |
|
yann@767
|
345 |
Leave blank if you don't know better.
|
yann@767
|
346 |
|
michael@2737
|
347 |
config ARCH_FLOAT
|
michael@2737
|
348 |
string
|
yann@2794
|
349 |
default "" if ! ARCH_SUPPORTS_WITH_FLOAT
|
michael@2737
|
350 |
default "hard" if ARCH_FLOAT_HW
|
michael@2737
|
351 |
default "soft" if ARCH_FLOAT_SW
|
michael@2739
|
352 |
default "softfp" if ARCH_FLOAT_SOFTFP
|
michael@2737
|
353 |
|
yann@2413
|
354 |
source "config.gen/arch.in.2"
|
yann@2413
|
355 |
|
yann@1
|
356 |
endmenu
|