1 | /* eva_app.c -- Glue code for linking apps to run under GDB debugger control. |
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2 | * |
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3 | * Copyright (c) 2001 Red Hat, Inc. |
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4 | * |
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5 | * The authors hereby grant permission to use, copy, modify, distribute, |
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6 | * and license this software and its documentation for any purpose, provided |
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7 | * that existing copyright notices are retained in all copies and that this |
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8 | * notice is included verbatim in any distributions. No written agreement, |
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9 | * license, or royalty fee is required for any of the authorized uses. |
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10 | * Modifications to this software may be copyrighted by their authors |
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11 | * and need not follow the licensing terms described here, provided that |
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12 | * the new terms are clearly indicated on the first page of each file where |
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13 | * they apply. |
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14 | */ |
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15 | #include "glue.h" |
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16 | |
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17 | typedef void (*write_proc_t)(char *buf, int nbytes); |
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18 | typedef int (*read_proc_t)(char *buf, int nbytes); |
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19 | |
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20 | /* There is no "syscall", so we just call directly into the stub code |
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21 | at fixed addresses. */ |
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22 | #define STUB_WRITE(p,n) ((write_proc_t)0x8084)((p),(n)) |
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23 | #define STUB_READ(p,n) ((read_proc_t)0x8088)((p),(n)) |
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24 | |
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25 | /* |
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26 | * print -- do a raw print of a string |
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27 | */ |
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28 | void |
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29 | print(char *ptr) |
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30 | { |
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31 | STUB_WRITE(ptr, strlen(ptr)); |
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32 | } |
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33 | |
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34 | /* |
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35 | * write -- write bytes to the serial port. Ignore fd, since |
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36 | * stdout and stderr are the same. Since we have no filesystem, |
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37 | * open will only return an error. |
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38 | */ |
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39 | int |
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40 | _write (int fd, char *buf, int nbytes) |
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41 | { |
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42 | STUB_WRITE(buf, nbytes); |
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43 | return (nbytes); |
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44 | } |
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45 | |
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46 | int |
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47 | _read (int fd, char *buf, int nbytes) |
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48 | { |
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49 | return STUB_READ(buf, nbytes); |
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50 | } |
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51 | |
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52 | extern char _end[]; |
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53 | #define HEAP_LIMIT ((char *)0xffff) |
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54 | |
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55 | void * |
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56 | _sbrk(int inc) |
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57 | { |
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58 | static char *heap_ptr = _end; |
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59 | void *base; |
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60 | |
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61 | if (inc > (HEAP_LIMIT - heap_ptr)) |
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62 | return (void *)-1; |
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63 | |
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64 | base = heap_ptr; |
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65 | heap_ptr += inc; |
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66 | |
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67 | return base; |
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68 | } |
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69 | |
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70 | void |
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71 | _exit(int n) |
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72 | { |
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73 | while (1) |
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74 | { |
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75 | asm volatile ("nop"); |
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76 | asm volatile (".hword 0x0006"); /* breakpoint (special illegal insn) */ |
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77 | } |
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78 | } |
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