[acc25ee] | 1 | # |
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| 2 | # $Id$ |
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| 3 | # |
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| 4 | |
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| 5 | The code in this directory has been taken WITH PERMISSION from |
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| 6 | Gabriel Paubert, paubert@iram.es. The main reason for having |
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| 7 | a separate bootloader for PreP compliant firmware is that the |
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| 8 | initial code is relocated by firmware at an unknow address |
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| 9 | (actually 0x5000 on motorola MCP750) and that as Gabriel I |
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| 10 | think having a relocatable bootloder code is a must. |
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| 11 | |
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| 12 | So the way of building a binary executable that can be booted via |
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| 13 | hard disk or network boot goes like this : |
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| 14 | |
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| 15 | - make a RTEMS executable, |
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| 16 | - put is as data section in the bootloder binary, |
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| 17 | - relink the loader (see make-exe macros for details), |
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| 18 | |
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| 19 | I would like to thank Gabriel for his support and his code. |
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| 20 | The original code can be found in form of a patch to official linux |
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| 21 | kernel at (I insist not vger ppc kernel or Imac ppc kernels!!) : |
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| 22 | |
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| 23 | <ftp://vlab1.iram.es/pub/linux-2.2/> |
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| 24 | |
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| 25 | After applying the patch, the code is located in a new directory |
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| 26 | called prepboot. |
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| 27 | |
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| 28 | (NB : note use ftp not netscape...) |
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| 29 | |
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| 30 | Note that the actual code differs a lot since Gabriel choose to use |
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| 31 | a CHRP compliant mapping instead of a Prep Mapping to save |
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| 32 | BATs. I had no time to upgrade the code to its new one allthough |
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| 33 | I agree it should be done... |
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| 34 | |
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| 35 | I have also splitted the original code to have a more modular |
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| 36 | design enabling to reuse code between the loader and RTEMS |
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| 37 | initialization (e.g printk, ...). |
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| 38 | |
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| 39 | Eric Valette (valette@crf.canon.fr) |
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| 40 | |
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| 41 | |
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