1 | # |
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2 | # $Id$ |
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3 | # |
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4 | |
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5 | Joel's Note: |
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6 | |
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7 | This has some information which is specific to 3.6.0. Other parts of the |
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8 | document should be merged with the main RTEMS READMEs. Procedures for |
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9 | building a boot floppy, from a network server, and other information |
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10 | specific to this BSP should remain in this file. |
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11 | |
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12 | ----------- |
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13 | |
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14 | RTEMS PC386 BSP HOWTO: |
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15 | |
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16 | 1. Introduction |
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17 | --------------- |
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18 | |
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19 | This howto tries to explain how to setup the RTEMS host |
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20 | environment on a Linux based PC so that RTEMS applications can be |
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21 | built for and run in a bare PC 386+. |
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22 | |
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23 | Please note that everything in the following text using the |
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24 | notation '<...>' is just an alias to something and should always be |
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25 | substituted by the real thing! |
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26 | |
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27 | 2. Unarchiving |
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28 | -------------- |
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29 | |
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30 | Files which have been "tarred, zipped" (i.e. .tar.gz or .tgz |
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31 | extension) may be unarchived with a command similar to one of the |
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32 | following: |
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33 | |
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34 | gzcat <file>.tgz | tar xvof - |
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35 | |
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36 | OR |
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37 | |
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38 | gunzip -c <file>.tgz | tar xvof - |
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39 | |
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40 | OR |
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41 | |
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42 | gtar xzvf <file>.tgz |
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43 | |
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44 | NOTE: gunzip -c is equivalent to gzcat, while gtar is GNU tar. |
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45 | |
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46 | Given that the necessary utility programs are installed, any of |
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47 | the above commands will extract the contents of <file>.tar.gz into the |
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48 | current directory. All of the RTEMS components will be extracted into |
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49 | the subdirectory rtems-3.2.0. To view the contents of a component |
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50 | without restoring any files, use a command similar to the following: |
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51 | |
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52 | gzcat <file>.tgz | tar tvf - |
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53 | |
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54 | 3. The building tools (gcc, binutils, et al.) |
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55 | --------------------------------------------- |
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56 | |
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57 | The PC386 BSP was developed so that the Linux native building |
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58 | tools can be used to build the RTEMS binaries. |
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59 | |
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60 | With this in mind all you have to do is check if you have gcc + |
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61 | binutils (as, ld, ar, objcopy) installed in your system (which most |
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62 | probably you'll have) and check their versions. You can do so with: |
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63 | |
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64 | - 'gcc -v' (for gcc); --> version 2.7.2.1 |
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65 | - 'ld -v' (for binutils). --> version 2.8.1 (with BFD linux-2.8.1.0.1) |
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66 | |
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67 | The above mentioned versions of gcc and binutils are almost |
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68 | certainly guaranteed to work (their the ones we've been using). More |
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69 | recent versions should also be ok, and older versions may be ok too. |
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70 | |
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71 | The only known problem is with older versions of binutils which |
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72 | still don't have a 'binary' target in 'objcopy'. We need objcopy's |
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73 | binary target to produce our final binaries (this will probably be |
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74 | enhanced in the future, so we get them directly from the 'elf32-i386' |
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75 | object, but for now this is how we do it). There's a possible |
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76 | workaround this, using older versions of 'objdump' with the flags used |
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77 | to produce the Linux kernel binary. You can investigate this in the |
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78 | Linux source makefiles. This hasn't been tested. |
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79 | |
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80 | It should be ok to build a cross-compilation environment (gcc + |
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81 | binutils) that supports the 'elf32-i386' target, so that you can use a |
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82 | host system other than Linux. This hasn't been tested. |
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83 | |
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84 | You can get 'gcc' and 'binutils', both pre-compiled binaries for |
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85 | Linux and sources from: |
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86 | |
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87 | ftp://sunsite.unc.edu/pub/Linux/GCC/ |
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88 | |
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89 | binutils-2.8.1.0.1.bin.tar.gz |
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90 | binutils-2.8.1.0.1.tar.gz |
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91 | gcc-2.7.2.1.bin.tar.gz |
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92 | |
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93 | as well as from several other mirrors and sites. |
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94 | |
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95 | 4. Creating aliases for gcc and the binutils |
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96 | -------------------------------------------- |
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97 | |
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98 | The NEWLIB expects to be compiled by a cross-compiler. The easiest |
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99 | (as far as we could find out) way to do this, short of changing the |
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100 | configuration files is to make symbolic links from cross-compiler |
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101 | style names (the usual names with a 'i386-elf32-rtems-' prefix) to the |
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102 | real name. |
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103 | |
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104 | You can use the following shell script to create these links |
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105 | quickly. It assumes that the native Linux 'gcc' and 'binutils' reside |
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106 | in their usual place (i.e. '/usr/bin/'). It also assumes that you're |
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107 | running it in the directory where the aliases will reside (which we |
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108 | will refer to as <elf32-tools>). You should then add <elf32-tools> to |
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109 | you path. This is necessary for building the NEWLIB package. |
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110 | |
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111 | --- CUT HERE --- CUT HERE --- CUT HERE --- CUT HERE --- CUT HERE --- |
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112 | |
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113 | #!sh |
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114 | ln -sf /usr/bin/ar i386-elf32-rtems-ar |
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115 | ln -sf /usr/bin/as i386-elf32-rtems-as |
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116 | ln -sf /usr/bin/cpp i386-elf32-rtems-cpp |
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117 | ln -sf /usr/bin/gasp i386-elf32-rtems-gasp |
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118 | ln -sf /usr/bin/gcc i386-elf32-rtems-gcc |
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119 | ln -sf /usr/bin/ld i386-elf32-rtems-ld |
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120 | ln -sf /usr/bin/objcopy i386-elf32-rtems-objcopy |
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121 | ln -sf /usr/bin/objdump i386-elf32-rtems-objdump |
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122 | ln -sf /usr/bin/ranlib i386-elf32-rtems-ranlib |
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123 | |
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124 | --- CUT HERE --- CUT HERE --- CUT HERE --- CUT HERE --- CUT HERE --- |
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125 | |
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126 | 5. Building Newlib |
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127 | ------------------ |
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128 | |
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129 | The next step is to build and install the NEWLIB package. The |
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130 | version we've been using and have tested is: |
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131 | |
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132 | newlib-1.7.0-posix-rtems-3.6.0.tgz |
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133 | |
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134 | You can get it from: |
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135 | |
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136 | ftp://lancelot.gcs.redstone.army.mil/pub/rtems/releases/current/c/ |
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137 | |
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138 | After unarchiving the NEWLIB distribution (discussed earlier), the |
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139 | NEWLIB package must be configured for the desired host and target. |
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140 | |
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141 | This is accomplished by changing the current directory to the top |
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142 | level of the NEWLIB source tree and executing the configure script |
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143 | with the appropriate arguments. This step configures the NEWLIB source |
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144 | for the 'i386-elf32-rtems' target configuration. The libraries and |
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145 | include files will be installed at <install_point>. The --verbose |
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146 | option to the ./configure script is recommended so you can check how |
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147 | the configuration process is progressing. Meanwhile we must do a |
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148 | little patching: 'install.sh' and 'config.sub' are missing from the |
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149 | 'libgloss' sub-directory. A command sequence similar to the following |
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150 | should be used: |
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151 | |
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152 | cd newlib-<NEWLIB_Version> |
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153 | |
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154 | cp configure.sub libgloss |
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155 | cp install.sh libgloss |
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156 | |
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157 | CC=gcc CFLAGS="-O4 -g" ./configure --verbose \ |
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158 | --target=i386-elf32-rtems \ |
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159 | --prefix=<install_point> |
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160 | |
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161 | If the configure script successfully completes, then NEWLIB may be |
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162 | built. This step builds the NEWLIB package in the local directory and |
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163 | does NOT install any files. The example commands specifies that gcc |
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164 | should be used as the C compiler and the arguments to be used by gcc. |
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165 | |
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166 | A command similar to the following should be used: |
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167 | |
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168 | make CC="gcc" CFLAGS="-O4 -g" |
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169 | |
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170 | If the build process successfully completes, then the NEWLIB |
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171 | package is ready to install. A command similar to the following should |
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172 | be used: |
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173 | |
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174 | make CC="gcc" CFLAGS="-O4 -g" install |
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175 | |
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176 | If this successfully completes, then the NEWLIB package has been |
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177 | installed at <install_point>. |
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178 | |
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179 | The documentation for the NEWLIB package is formatted using |
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180 | TeX. If TeX and some supporting tools are installed on the development |
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181 | system, then the following command may be used to produce the |
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182 | documentation in the "DVI" format: |
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183 | |
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184 | gmake CC="gcc" CFLAGS="-O4 -g" dvi |
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185 | |
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186 | If while the documentation is being formatted, the message "Cross reference values unknown; you must run TeX again." is printed, then the "DVI" files generated by this command (e.g. *.dvi in every subdirectory with documentation) must be removed and the command reexecuted. |
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187 | |
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188 | 6. Modules |
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189 | ---------- |
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190 | |
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191 | Modules eases the process of manipulating the environment |
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192 | variables required to build RTEMS. If, for whatever reason, you do not |
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193 | wish to use Modules, then it will be necessary to manually modify |
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194 | shell initialization files and set the required RTEMS shell variables |
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195 | "manually." In this case, the Modules files are still the best place |
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196 | to look for information on what variables to set and example values. |
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197 | |
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198 | The Modules package was utilized by the RTEMS developers to make |
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199 | the initialization process shell independent. The Modules files used |
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200 | by the RTEMS developers to configure their user environment while |
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201 | working on a particular target board are included in the |
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202 | distribution. These require only simple modifications to be |
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203 | "localized" for the RTEMS developer. The modifications to these ASCII |
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204 | files can be made with an editor such as vi or emacs. |
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205 | |
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206 | The Modules Homepage is: |
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207 | |
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208 | http://www.modules.org/ |
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209 | |
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210 | You can get the Modules distribution (the latest version, which |
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211 | we've been using, is '3.0pre') via the homepage or directly from: |
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212 | |
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213 | ftp://ftp.modules.org/pub/distrib/Modules-3.0pre.tar.gz |
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214 | |
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215 | |
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216 | 6.1. New Modules users |
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217 | ---------------------- |
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218 | |
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219 | Install Modules on the development system following the |
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220 | instructions in the file README in the main Modules directory. When |
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221 | Modules has been installed and a user account setup to use Modules, |
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222 | then proceed to the section Current Modules Users. |
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223 | |
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224 | 6.2. Current Modules users |
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225 | -------------------------- |
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226 | |
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227 | If the host computer already utilizes the Modules package, then |
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228 | the assistance of the system administrator responsible for the Modules |
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229 | package will be required to perform the modifications described below. |
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230 | |
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231 | The system administrator must integrate the RTEMS modules into the |
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232 | existing Modules configuration. A first alternative is to copy all of |
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233 | the module files provided with RTEMS into an existing modulefiles |
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234 | directory. This requires that future updates of RTEMS modules will |
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235 | also have to be integrated into the existing modulefiles |
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236 | directory. This alternative is not recommended. |
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237 | |
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238 | The more preferable alternative is to add the RTEMS modulefiles |
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239 | directory to the MODULEPATH. This can be accomplished on an individual |
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240 | user or system wide basis. For individual users, the RTEMS modules |
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241 | directory can be added to the MODULEPATH of those users requiring |
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242 | access to RTEMS. The default MODULEPATH is established by the Modules |
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243 | initialization routine. Thus, the RTEMS modules directory must be |
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244 | added to the MODULEPATH in the user's shell initialization file |
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245 | (~/.profile or ~/.cshrc for example) following the Modules |
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246 | initialization statement. The proper way to accomplish this is to use |
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247 | the Modules use statement. For example, the following line should be |
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248 | added to the user's shell initialization file: |
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249 | |
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250 | module use <rtems_path>/modules/modulefiles |
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251 | |
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252 | For system wide access, the RTEMS modulefiles directory can be |
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253 | added to each of the shell initialization scripts in the existing |
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254 | Modules package. This will require modifying the initialization of |
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255 | MODULEPATH in each shell initialization file. |
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256 | |
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257 | After integrating RTEMS modules with the existing modules, one may |
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258 | proceed to the Configuring An RTEMS User section. |
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259 | |
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260 | 7. RTEMS |
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261 | -------- |
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262 | |
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263 | You can get the latest free release of the C distribuition of |
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264 | RTEMS (version 3.6.0), from: |
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265 | |
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266 | ftp://lancelot.gcs.redstone.army.mil/pub/rtems/releases/current/c/ |
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267 | |
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268 | Where you'll find: |
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269 | |
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270 | rtems-3.6.0.tgz or rtems-c_src.tgz - RTEMS sources; |
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271 | |
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272 | rtems-3.5.1-c_doc.tgz or rtems-c_doc.tgz - RTEMS documentation; |
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273 | |
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274 | individual_manuals/ - Sub-directory where you can get the |
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275 | manuals individually. |
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276 | |
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277 | Please note that the RTEMS documentation is slightly outdated |
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278 | (most noticeably some RTEMS primitives have different protoypes) since |
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279 | it refers to the previous release (3.5.1.) of RTEMS. |
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280 | |
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281 | After unarchiving the RTEMS distribution (discussed earlier), it |
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282 | is necessary to add the PC386 BSP to the source tree. This is done in |
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283 | two steps. |
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284 | |
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285 | The first step consists in unarchiving the |
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286 | 'rtems-3.6.0-PC386-BSP.tgz' archive over the standard rtems-3.6.0 |
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287 | distribution. It should be done in the same directory where |
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288 | 'rtems-3.6.0.tgz' was unarchived. |
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289 | |
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290 | Next you'll need to apply the patch in |
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291 | 'rtems-3.6.0-PC386-BSP.diff.gz' to the RTEMS source tree. The |
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292 | following command should be used: |
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293 | |
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294 | gzip -d -c rtems-3.6.0-PC386-BSP.diff.gz | patch |
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295 | |
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296 | also from the same directory where 'rtems-3.6.0.tgz' was unarchived. |
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297 | |
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298 | At this stage we have RTEMS + PC386 BSP, the user environment must |
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299 | be setup to build and install RTEMS. |
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300 | |
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301 | Using this process, you'll know which files are patched and which |
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302 | files are new. |
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303 | |
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304 | 7.1. Board Support Package |
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305 | -------------------------- |
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306 | |
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307 | A Board Support Package (BSP) is a collection of device drivers, |
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308 | initialization code, and linker scripts necessary to execute RTEMS on |
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309 | a particular target board. The minimum set of device drivers for a |
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310 | single processor target includes a Clock, Console I/O, and Benchmark |
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311 | Timer device drivers. |
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312 | |
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313 | The source code for the PC386 BSP can be found in the directory 'c/src/lib/libbsp/i386/pc386. |
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314 | |
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315 | 7.2. Makefile Configuration Files |
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316 | --------------------------------- |
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317 | |
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318 | There are two target specific configuration files used by the |
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319 | Makefile system. These configuration files specify detailed |
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320 | information about the toolset, the compilation process, as well as |
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321 | some general configuration information regarding the target and the |
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322 | development environment. The following is a list of these |
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323 | configuration files: |
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324 | |
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325 | c/make/compilers/gcc-pc386.cfg |
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326 | |
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327 | c/make/custom/pc386.cfg |
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328 | |
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329 | If you're compiling to a i386+ with FPU in a standard Linux |
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330 | environment, you shouldn't require any changes to these files in order |
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331 | to build RTEMS (though you'll probably want to fine tune them later |
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332 | on). |
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333 | |
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334 | 7.3 Creating a Customized Modules File |
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335 | -------------------------------------- |
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336 | |
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337 | Files which the Modules packages may use to customize a user's |
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338 | environment for building, installing, and modifying RTEMS are found in |
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339 | the c/Modules/rtems directory. Each of the files in this directory |
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340 | corresponds to the configuration used by the RTEMS developers for |
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341 | building and installing RTEMS for a particular target board. These |
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342 | files contain the Modules commands necessary to set the following |
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343 | environment variables: |
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344 | |
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345 | Variable Description |
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346 | |
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347 | RTEMS_BSP The name of the target BSP (e.g. |
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348 | mvme136 or cvme961). |
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349 | |
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350 | RTEMS_ROOT The full path of root directory of the |
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351 | RTEMS source code. |
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352 | |
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353 | RTEMS_GNUTOOLS The full path of the root directory for |
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354 | the cross-development toolset to be |
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355 | used. |
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356 | |
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357 | RTEMS_HOST The name of the operating system for |
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358 | the development system. |
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359 | |
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360 | RTEMS_LIBC_DIR The full path of the root directory for |
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361 | the Standard C Library to be used. |
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362 | |
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363 | |
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364 | The Modules file for the PC386 BSP is: 'c/Modules/rtems/nav-pc386'. |
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365 | |
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366 | You MUST edit this file and set the following variables to the |
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367 | correct values in your system: |
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368 | |
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369 | - RTEMS_ROOT; |
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370 | - RTEMS_GNUTOOLS (this is the directory where the links in 4. |
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371 | were created); |
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372 | - RTEMS_LIBC_DIR (this is the directory where the Newlib target |
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373 | specific root is installed, and with reference |
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374 | to 5. should be '<install_point>/i386-elf32-rtems'). |
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375 | |
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376 | 7.4 Configuring an RTEMS User Using Modules |
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377 | ------------------------------------------- |
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378 | |
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379 | Each user building and installing RTEMS must have their |
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380 | environment configured. The user environment must have a set of |
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381 | variables set in it which indicate the target BSP, host operating |
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382 | system, and numerous paths. |
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383 | |
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384 | If you'll just be using the PC386 BSP then a line of the following |
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385 | type may be added to the initialization file for your shell after the |
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386 | Modules initialization statement. |
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387 | |
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388 | module load nav-pc386 |
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389 | |
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390 | Note that you must logout and login before any changes to the shell |
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391 | initialization files will take effect. |
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392 | |
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393 | If you don't wish the RTEMS environment configuration to be added |
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394 | to your shell initialization file, then the "module load" statement |
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395 | may be entered at the command line. |
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396 | |
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397 | You may switch from one RTEMS configuration to another with either |
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398 | of the following command sequences: |
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399 | |
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400 | module unload <old_rtems_modulefile> |
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401 | module load <new_rtems_modulefile> |
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402 | |
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403 | OR |
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404 | |
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405 | module switch <old_rtems_modulefile> <new_rtems_modulefile> |
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406 | |
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407 | The command "module avail" may be used to obtain a list of the |
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408 | Module files which are available to be loaded using the "module load" |
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409 | command. |
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410 | |
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411 | The command "module list" provides a list of the currently loaded |
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412 | Modules. |
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413 | |
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414 | 7.5. Building RTEMS |
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415 | ------------------- |
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416 | |
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417 | By default, the PC386 RTEMS BSP is installed into the directory |
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418 | 'c/pc386_i386'. If this is not the desired installation point, then |
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419 | modify the following line in the file 'c/make/custom/pc386.cfg': |
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420 | |
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421 | PROJECT_HOME=$(PROJECT_ROOT)/$(RTEMS_BSP) |
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422 | |
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423 | Once the root directory of the install point has been set, the |
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424 | following steps are required to build and install RTEMS (NOTE: If the |
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425 | Modules files are used, the environment variable '$r' is set to point |
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426 | to the top directory for the RTEMS implementation selected in the |
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427 | current environment. This is the directory 'c' in the RTEMS |
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428 | distribution.): |
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429 | |
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430 | cd $r |
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431 | make install |
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432 | |
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433 | If this completes successfully, then RTEMS has been built and |
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434 | installed. |
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435 | |
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436 | 8. RTEMS Tests |
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437 | -------------- |
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438 | |
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439 | If you've completed the last step successfully, you'll find the |
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440 | RTEMS sample and test files in the 'c/pc386_i386/tests' directory. |
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441 | |
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442 | The 'sp*.bt' are the single processor tests and should all work |
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443 | correctly. The same applies to the 'tm*.bt' which are the timing |
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444 | tests. |
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445 | |
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446 | The other sample ('*.bt') files should also work with the |
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447 | exception of 'spfatal.bt' and 'stackchk.bt' (see 9.). |
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448 | |
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449 | To load the '*.bt' files you can either run the 'diskboot.exe' |
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450 | (which can be found in 'c/pc386_i386/build-tools') under DOS with a |
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451 | command line like (this is just a quick and dirty loader - you'll have |
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452 | to press return twice after entering it): |
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453 | |
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454 | diskboot sp01.bt |
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455 | |
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456 | Alternatively, if you have a PC connected to a network with a |
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457 | BOOTP server and a TFTP server (this can very well be you're Linux |
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458 | RTEMS host system), you can use Gero Kuhlmann's netboot loader, to |
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459 | load RTEMS to a diskless PC across a network. You can get it from: |
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460 | |
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461 | ftp://sunsite.unc.edu/pub/Linux/system/boot/netboot-0.7.2.tar.gz |
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462 | |
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463 | Follow the instructions contained in the package to setup the |
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464 | server(s) and to build a boot ROM for the client PC network card, or a |
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465 | boot diskette, and the client should be able to load the '*.bt' files |
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466 | from the server. |
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467 | |
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468 | For the network loader every relocation address from 0x10200 to |
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469 | 0x80200 are known to work correctly. For the DOS loader, relocation |
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470 | addresses 0x20200, 0x40200 and 0x80200 are known to work under DOS |
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471 | 5.00, DOS 6.xx and DOS 7.00. You can set the relocation address in |
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472 | 'c/make/compilers/gcc-pc386.cfg' by setting the value of the |
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473 | 'RELOCADDR' variable. |
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474 | |
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475 | 9. Important Notes |
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476 | ------------------ |
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477 | |
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478 | The optional stack checker extension ('stackchk') doesn't seem to |
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479 | be working properly. It reports blown task stacks even if everything |
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480 | seems to work properly when 'stackchk' isn't activated... This should |
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481 | be properly investigated: the problem can reside with the 'PC386 BSP', |
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482 | or in the interface between 'stackchk' and the BSP (maybe something |
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483 | isn't being correctly initialized...). Since this doesn't seem to be a |
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484 | serious BSP problem, it hasn't been dealt with, due to more prioritary |
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485 | problems. |
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486 | |
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487 | The tests which exercise the fatal error mecanisms don't work |
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488 | correctly either. I've been told by Joe that 'spfatal' is outdated, and |
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489 | so this really isn't surprising. |
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490 | |
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491 | This issues may be important and should be investigated as soon as |
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492 | possible. |
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493 | |
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494 | When programming interrupt handlers take into account that the PIC |
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495 | is reprogrammed and so you should use the interface functions provided |
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496 | to garantee that everything works ok. |
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