[a8d953f] | 1 | #define GDB_STUB_ENABLE_THREAD_SUPPORT 1 |
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| 2 | /**************************************************************************** |
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| 3 | |
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[6128a4a] | 4 | THIS SOFTWARE IS NOT COPYRIGHTED |
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| 5 | |
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[a8d953f] | 6 | HP offers the following for use in the public domain. HP makes no |
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[6128a4a] | 7 | warranty with regard to the software or it's performance and the |
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[a8d953f] | 8 | user accepts the software "AS IS" with all faults. |
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| 9 | |
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| 10 | HP DISCLAIMS ANY WARRANTIES, EXPRESS OR IMPLIED, WITH REGARD |
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| 11 | TO THIS SOFTWARE INCLUDING BUT NOT LIMITED TO THE WARRANTIES |
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| 12 | OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
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| 13 | |
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| 14 | ****************************************************************************/ |
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| 15 | |
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| 16 | /**************************************************************************** |
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[6128a4a] | 17 | * Header: remcom.c,v 1.34 91/03/09 12:29:49 glenne Exp $ |
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[a8d953f] | 18 | * |
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[6128a4a] | 19 | * Module name: remcom.c $ |
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[a8d953f] | 20 | * Revision: 1.34 $ |
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| 21 | * Date: 91/03/09 12:29:49 $ |
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| 22 | * Contributor: Lake Stevens Instrument Division$ |
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[6128a4a] | 23 | * |
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[a8d953f] | 24 | * Description: low level support for gdb debugger. $ |
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| 25 | * |
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| 26 | * Considerations: only works on target hardware $ |
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| 27 | * |
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| 28 | * Written by: Glenn Engel $ |
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[6128a4a] | 29 | * ModuleState: Experimental $ |
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[a8d953f] | 30 | * |
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| 31 | * NOTES: See Below $ |
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[6128a4a] | 32 | * |
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[a8d953f] | 33 | * To enable debugger support, two things need to happen. One, a |
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| 34 | * call to set_debug_traps() is necessary in order to allow any breakpoints |
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| 35 | * or error conditions to be properly intercepted and reported to gdb. |
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| 36 | * Two, a breakpoint needs to be generated to begin communication. This |
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| 37 | * is most easily accomplished by a call to breakpoint(). Breakpoint() |
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| 38 | * simulates a breakpoint by executing a trap #1. The breakpoint instruction |
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| 39 | * is hardwired to trap #1 because not to do so is a compatibility problem-- |
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| 40 | * there either should be a standard breakpoint instruction, or the protocol |
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| 41 | * should be extended to provide some means to communicate which breakpoint |
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| 42 | * instruction is in use (or have the stub insert the breakpoint). |
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[6128a4a] | 43 | * |
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[a8d953f] | 44 | * Some explanation is probably necessary to explain how exceptions are |
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| 45 | * handled. When an exception is encountered the 68000 pushes the current |
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| 46 | * program counter and status register onto the supervisor stack and then |
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| 47 | * transfers execution to a location specified in it's vector table. |
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| 48 | * The handlers for the exception vectors are hardwired to jmp to an address |
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[6128a4a] | 49 | * given by the relation: (exception - 256) * 6. These are decending |
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[a8d953f] | 50 | * addresses starting from -6, -12, -18, ... By allowing 6 bytes for |
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[6128a4a] | 51 | * each entry, a jsr, jmp, bsr, ... can be used to enter the exception |
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[a8d953f] | 52 | * handler. Using a jsr to handle an exception has an added benefit of |
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| 53 | * allowing a single handler to service several exceptions and use the |
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| 54 | * return address as the key differentiation. The vector number can be |
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| 55 | * computed from the return address by [ exception = (addr + 1530) / 6 ]. |
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| 56 | * The sole purpose of the routine _catchException is to compute the |
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| 57 | * exception number and push it on the stack in place of the return address. |
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| 58 | * The external function exceptionHandler() is |
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| 59 | * used to attach a specific handler to a specific m68k exception. |
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| 60 | * For 68020 machines, the ability to have a return address around just |
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| 61 | * so the vector can be determined is not necessary because the '020 pushes an |
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| 62 | * extra word onto the stack containing the vector offset |
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[6128a4a] | 63 | * |
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[a8d953f] | 64 | * Because gdb will sometimes write to the stack area to execute function |
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| 65 | * calls, this program cannot rely on using the supervisor stack so it |
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[6128a4a] | 66 | * uses it's own stack area reserved in the int array remcomStack. |
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| 67 | * |
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[a8d953f] | 68 | ************* |
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| 69 | * |
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| 70 | * The following gdb commands are supported: |
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[6128a4a] | 71 | * |
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[a8d953f] | 72 | * command function Return value |
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[6128a4a] | 73 | * |
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[a8d953f] | 74 | * g return the value of the CPU registers hex data or ENN |
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| 75 | * G set the value of the CPU registers OK or ENN |
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[6128a4a] | 76 | * |
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[a8d953f] | 77 | * mAA..AA,LLLL Read LLLL bytes at address AA..AA hex data or ENN |
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| 78 | * MAA..AA,LLLL: Write LLLL bytes at address AA.AA OK or ENN |
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[6128a4a] | 79 | * |
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[a8d953f] | 80 | * c Resume at current address SNN ( signal NN) |
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| 81 | * cAA..AA Continue at address AA..AA SNN |
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[6128a4a] | 82 | * |
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[a8d953f] | 83 | * s Step one instruction SNN |
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| 84 | * sAA..AA Step one instruction from AA..AA SNN |
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[6128a4a] | 85 | * |
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[a8d953f] | 86 | * k kill |
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| 87 | * |
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| 88 | * ? What was the last sigval ? SNN (signal NN) |
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[6128a4a] | 89 | * |
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| 90 | * All commands and responses are sent with a packet which includes a |
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| 91 | * checksum. A packet consists of |
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| 92 | * |
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[a8d953f] | 93 | * $<packet info>#<checksum>. |
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[6128a4a] | 94 | * |
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[a8d953f] | 95 | * where |
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| 96 | * <packet info> :: <characters representing the command or response> |
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| 97 | * <checksum> :: < two hex digits computed as modulo 256 sum of <packetinfo>> |
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[6128a4a] | 98 | * |
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[a8d953f] | 99 | * When a packet is received, it is first acknowledged with either '+' or '-'. |
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| 100 | * '+' indicates a successful transfer. '-' indicates a failed transfer. |
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[6128a4a] | 101 | * |
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[a8d953f] | 102 | * Example: |
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[6128a4a] | 103 | * |
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[a8d953f] | 104 | * Host: Reply: |
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| 105 | * $m0,10#2a +$00010203040506070809101112131415#42 |
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[6128a4a] | 106 | * |
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[a8d953f] | 107 | *************************************************************************** |
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| 108 | * added 05/27/02 by IMD, Thomas Doerfler: |
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| 109 | * XAA..AA,LLLL: Write LLLL binary bytes at address AA.AA OK or ENN |
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| 110 | ****************************************************************************/ |
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| 111 | |
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| 112 | #include <stdio.h> |
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| 113 | #include <string.h> |
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| 114 | #include <setjmp.h> |
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| 115 | /* #include <asm.h>*/ |
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| 116 | #include <rtems.h> |
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| 117 | #include <rtems/score/cpu.h> |
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| 118 | #include "gdb_if.h" |
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| 119 | |
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| 120 | #if defined(GDB_STUB_ENABLE_THREAD_SUPPORT) |
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| 121 | static char do_threads = 1; /* != 0 means we are supporting threads */ |
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| 122 | int current_thread_registers[NUMREGBYTES/4]; |
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| 123 | #endif |
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| 124 | |
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| 125 | /************************************************************************ |
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| 126 | * |
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[6128a4a] | 127 | * external low-level support routines |
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[a8d953f] | 128 | */ |
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| 129 | typedef void (*ExceptionHook)(int); /* pointer to function with int parm */ |
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| 130 | typedef void (*Function)(); /* pointer to a function */ |
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| 131 | |
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| 132 | extern void putDebugChar(); /* write a single character */ |
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| 133 | extern int getDebugChar(); /* read and return a single char */ |
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| 134 | |
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| 135 | /************************/ |
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| 136 | /* FORWARD DECLARATIONS */ |
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| 137 | /************************/ |
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| 138 | static void |
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| 139 | initializeRemcomErrorFrame (); |
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| 140 | |
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| 141 | /************************************************************************/ |
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| 142 | /* BUFMAX defines the maximum number of characters in inbound/outbound buffers*/ |
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| 143 | /* at least NUMREGBYTES*2 are needed for register packets */ |
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| 144 | #define BUFMAX 400 |
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| 145 | |
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[39d08d55] | 146 | static bool initialized = false ; /* boolean flag. != 0 means we've been initialized */ |
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[a8d953f] | 147 | |
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| 148 | int remote_debug; |
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[6128a4a] | 149 | /* debug > 0 prints ill-formed commands in valid packets & checksum errors */ |
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[a8d953f] | 150 | |
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| 151 | const char gdb_hexchars[]="0123456789abcdef"; |
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| 152 | #define highhex(x) gdb_hexchars [(x >> 4) & 0xf] |
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| 153 | #define lowhex(x) gdb_hexchars [x & 0xf] |
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| 154 | |
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[d4b4664b] | 155 | |
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[a8d953f] | 156 | /* We keep a whole frame cache here. "Why?", I hear you cry, "doesn't |
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| 157 | GDB handle that sort of thing?" Well, yes, I believe the only |
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| 158 | reason for this cache is to save and restore floating point state |
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| 159 | (fsave/frestore). A cleaner way to do this would be to make the |
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| 160 | fsave data part of the registers which GDB deals with like any |
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| 161 | other registers. This should not be a performance problem if the |
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| 162 | ability to read individual registers is added to the protocol. */ |
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| 163 | |
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| 164 | typedef struct FrameStruct |
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| 165 | { |
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| 166 | struct FrameStruct *previous; |
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| 167 | int exceptionPC; /* pc value when this frame created */ |
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| 168 | int exceptionVector; /* cpu vector causing exception */ |
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| 169 | short frameSize; /* size of cpu frame in words */ |
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| 170 | short sr; /* for 68000, this not always sr */ |
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| 171 | int pc; |
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| 172 | short format; |
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| 173 | int fsaveHeader; |
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| 174 | int morejunk[0]; /* exception frame, fp save... */ |
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| 175 | } Frame; |
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| 176 | |
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| 177 | #define FRAMESIZE 500 |
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| 178 | int gdbFrameStack[FRAMESIZE]; |
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| 179 | static Frame *lastFrame; |
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| 180 | |
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| 181 | /* |
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| 182 | * these should not be static cuz they can be used outside this module |
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| 183 | */ |
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| 184 | int registers[NUMREGBYTES/4]; |
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| 185 | int superStack; |
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| 186 | |
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| 187 | #define STACKSIZE 10000 |
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| 188 | int remcomStack[STACKSIZE/sizeof(int)]; |
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| 189 | static int* stackPtr = &remcomStack[STACKSIZE/sizeof(int) - 1]; |
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| 190 | |
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| 191 | /* |
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| 192 | * In many cases, the system will want to continue exception processing |
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[6128a4a] | 193 | * when a continue command is given. |
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[a8d953f] | 194 | * oldExceptionHook is a function to invoke in this case. |
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| 195 | */ |
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| 196 | |
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| 197 | static ExceptionHook oldExceptionHook; |
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[6128a4a] | 198 | /* the size of the exception stack on the 68020/30/40/CPU32 varies with |
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[a8d953f] | 199 | * the type of exception. The following table is the number of WORDS used |
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| 200 | * for each exception format. |
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| 201 | * This table should be common for all 68k with VBR |
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| 202 | * although each member only implements some of the formats |
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| 203 | */ |
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| 204 | const short exceptionSize[] = { 4,4,6,6,4,4,4,30,29,10,16,46,12,4,4,4 }; |
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| 205 | |
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| 206 | /************* jump buffer used for setjmp/longjmp **************************/ |
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| 207 | jmp_buf remcomEnv; |
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| 208 | |
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| 209 | /*************************** ASSEMBLY CODE MACROS *************************/ |
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| 210 | /* */ |
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| 211 | |
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| 212 | #ifdef __HAVE_68881__ |
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| 213 | /* do an fsave, then remember the address to begin a restore from */ |
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[7922b39c] | 214 | #define SAVE_FP_REGS() __asm__ (" fsave -(%a0)"); \ |
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| 215 | __asm__ (" fmovem.x %fp0-%fp7,registers+72"); \ |
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| 216 | __asm__ (" fmovem.l %fpcr/%fpsr/%fpi,registers+168"); |
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[a8d953f] | 217 | #define RESTORE_FP_REGS() \ |
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[7922b39c] | 218 | __asm__ (" \n\ |
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[a8d953f] | 219 | fmovem.l registers+168,%fpcr/%fpsr/%fpi \n\ |
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| 220 | fmovem.x registers+72,%fp0-%fp7 \n\ |
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| 221 | cmp.l #-1,(%a0) | skip frestore flag set ? \n\ |
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| 222 | beq skip_frestore \n\ |
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| 223 | frestore (%a0)+ \n\ |
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| 224 | skip_frestore: \n\ |
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| 225 | "); |
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| 226 | |
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| 227 | #else |
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| 228 | #define SAVE_FP_REGS() |
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| 229 | #define RESTORE_FP_REGS() |
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| 230 | #endif /* __HAVE_68881__ */ |
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| 231 | |
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| 232 | void return_to_super(); |
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| 233 | void return_to_user(); |
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| 234 | extern void _catchException (); |
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| 235 | |
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| 236 | void m68k_exceptionHandler |
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| 237 | ( |
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| 238 | int vecnum, /* vector index to hook at */ |
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| 239 | void *vector /* address of handler function */ |
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| 240 | ) |
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| 241 | { |
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| 242 | void **vec_base = NULL; |
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| 243 | #if M68K_HAS_VBR |
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| 244 | /* |
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| 245 | * get vector base register |
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| 246 | */ |
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[7922b39c] | 247 | __asm__ (" movec.l %%vbr,%0":"=a" (vec_base)); |
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[a8d953f] | 248 | #endif |
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| 249 | vec_base[vecnum] = vector; |
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| 250 | } |
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| 251 | |
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| 252 | ExceptionHook exceptionHook; /* hook variable for errors/exceptions */ |
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| 253 | |
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[6128a4a] | 254 | void m68k_stub_dummy_asm_wrapper() |
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[a8d953f] | 255 | /* |
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[6128a4a] | 256 | * this dummy wrapper function ensures, |
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[a8d953f] | 257 | * that the C compiler manages sections properly |
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| 258 | */ |
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| 259 | { |
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[7922b39c] | 260 | __asm__ ("\n\ |
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[f14b925] | 261 | .globl return_to_super \n\ |
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| 262 | return_to_super: \n\ |
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| 263 | move.l registers+60,%sp /* get new stack pointer */ \n\ |
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| 264 | move.l lastFrame,%a0 /* get last frame info */ \n\ |
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| 265 | bra return_to_any \n\ |
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| 266 | \n\ |
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| 267 | .globl _return_to_user \n\ |
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| 268 | return_to_user: \n\ |
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| 269 | move.l registers+60,%a0 /* get usp */ \n\ |
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| 270 | move.l %a0,%usp /* set usp */ \n\ |
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| 271 | move.l superStack,%sp /* get original stack pointer */ \n\ |
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| 272 | \n\ |
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| 273 | return_to_any: \n\ |
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| 274 | move.l lastFrame,%a0 /* get last frame info */ \n\ |
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| 275 | move.l (%a0)+,lastFrame /* link in previous frame */ \n\ |
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| 276 | addq.l #8,%a0 /* skip over pc, vector#*/ \n\ |
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| 277 | move.w (%a0)+,%d0 /* get # of words in cpu frame */ \n\ |
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| 278 | add.w %d0,%a0 /* point to end of data */ \n\ |
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| 279 | add.w %d0,%a0 /* point to end of data */ \n\ |
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| 280 | move.l %a0,%a1 \n\ |
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| 281 | # \n\ |
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| 282 | # copy the stack frame \n\ |
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| 283 | subq.l #1,%d0 \n\ |
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| 284 | copyUserLoop: \n\ |
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| 285 | move.w -(%a1),-(%sp) \n\ |
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| 286 | dbf %d0,copyUserLoop \n\ |
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| 287 | "); |
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[6128a4a] | 288 | RESTORE_FP_REGS() |
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[7922b39c] | 289 | __asm__ (" movem.l registers,%d0-%d7/%a0-%a6"); |
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| 290 | __asm__ (" rte"); /* pop and go! */ |
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[a8d953f] | 291 | |
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[7922b39c] | 292 | #define DISABLE_INTERRUPTS() __asm__ (" oriw #0x0700,%sr"); |
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| 293 | #define BREAKPOINT() __asm__ (" trap #2"); |
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[a8d953f] | 294 | |
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| 295 | /* this function is called immediately when a level 7 interrupt occurs */ |
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| 296 | /* if the previous interrupt level was 7 then we're already servicing */ |
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| 297 | /* this interrupt and an rte is in order to return to the debugger. */ |
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| 298 | /* For the 68000, the offset for sr is 6 due to the jsr return address */ |
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[7922b39c] | 299 | __asm__ (" \n\ |
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[f14b925] | 300 | .text \n\ |
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| 301 | .globl _debug_level7 \n\ |
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| 302 | _debug_level7: \n\ |
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[a8d953f] | 303 | move.w %d0,-(%sp)"); |
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| 304 | #if M68K_HAS_VBR |
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[7922b39c] | 305 | __asm__ (" move.w 2(%sp),%d0"); |
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[a8d953f] | 306 | #else |
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[7922b39c] | 307 | __asm__ (" move.w 6(%sp),%d0"); |
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[a8d953f] | 308 | #endif |
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[7922b39c] | 309 | __asm__ (" andi.w #0x700,%d0 \n\ |
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[f14b925] | 310 | cmpi.w #0x700,%d0 \n\ |
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| 311 | beq already7 \n\ |
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| 312 | move.w (%sp)+,%d0 \n\ |
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| 313 | bra _catchException \n\ |
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| 314 | already7: \n\ |
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[a8d953f] | 315 | move.w (%sp)+,%d0"); |
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| 316 | #if !M68K_HAS_VBR |
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[7922b39c] | 317 | __asm__ (" lea 4(%sp),%sp"); /* pull off 68000 return address */ |
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[a8d953f] | 318 | #endif |
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[7922b39c] | 319 | __asm__ (" rte"); |
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[a8d953f] | 320 | |
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| 321 | #if M68K_HAS_VBR |
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| 322 | /* This function is called when a 68020 exception occurs. It saves |
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| 323 | * all the cpu and fpcp regs in the _registers array, creates a frame on a |
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| 324 | * linked list of frames which has the cpu and fpcp stack frames needed |
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| 325 | * to properly restore the context of these processors, and invokes |
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| 326 | * an exception handler (remcom_handler). |
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| 327 | * |
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| 328 | * stack on entry: stack on exit: |
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| 329 | * N bytes of junk exception # MSWord |
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| 330 | * Exception Format Word exception # MSWord |
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[6128a4a] | 331 | * Program counter LSWord |
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| 332 | * Program counter MSWord |
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| 333 | * Status Register |
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| 334 | * |
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| 335 | * |
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[a8d953f] | 336 | */ |
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[7922b39c] | 337 | __asm__ (" \n\ |
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[f14b925] | 338 | .text \n\ |
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| 339 | .globl _catchException \n\ |
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[a8d953f] | 340 | _catchException:"); |
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| 341 | DISABLE_INTERRUPTS(); |
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[7922b39c] | 342 | __asm__ (" \n\ |
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[f14b925] | 343 | movem.l %d0-%d7/%a0-%a6,registers /* save registers */ \n\ |
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| 344 | move.l lastFrame,%a0 /* last frame pointer */ \n\ |
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[a8d953f] | 345 | "); |
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[6128a4a] | 346 | SAVE_FP_REGS(); |
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[7922b39c] | 347 | __asm__ ("\n\ |
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[ee55cdb] | 348 | lea registers,%a5 /* get address of registers */\n\ |
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| 349 | move.w (%sp),%d1 /* get status register */\n\ |
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| 350 | move.w %d1,66(%a5) /* save sr */ \n\ |
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| 351 | move.l 2(%sp),%a4 /* save pc in a4 for later use */\n\ |
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| 352 | move.w 6(%sp),%d0 /* get '020 exception format */\n\ |
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| 353 | move.w %d0,%d2 /* make a copy of format word */\n\ |
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| 354 | #\n\ |
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| 355 | # compute exception number\n\ |
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| 356 | and.l #0xfff,%d2 /* mask off vector offset */\n\ |
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| 357 | lsr.w #2,%d2 /* divide by 4 to get vect num */\n\ |
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| 358 | /* #if 1 */\n\ |
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| 359 | cmp.l #33,%d2\n\ |
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| 360 | bne nopc_adjust\n\ |
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| 361 | subq.l #2,%a4\n\ |
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| 362 | nopc_adjust:\n\ |
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| 363 | /* #endif */\n\ |
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| 364 | move.l %a4,68(%a5) /* save pc in _regisers[] */\n\ |
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| 365 | \n\ |
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| 366 | #\n\ |
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| 367 | # figure out how many bytes in the stack frame\n\ |
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| 368 | andi.w #0xf000,%d0 /* mask off format type */\n\ |
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| 369 | rol.w #5,%d0 /* rotate into the low byte *2 */\n\ |
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| 370 | lea exceptionSize,%a1 \n\ |
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| 371 | add.w %d0,%a1 /* index into the table */\n\ |
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| 372 | move.w (%a1),%d0 /* get number of words in frame */\n\ |
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| 373 | move.w %d0,%d3 /* save it */\n\ |
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| 374 | sub.w %d0,%a0 /* adjust save pointer */\n\ |
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| 375 | sub.w %d0,%a0 /* adjust save pointer(bytes) */\n\ |
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| 376 | move.l %a0,%a1 /* copy save pointer */\n\ |
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| 377 | subq.l #1,%d0 /* predecrement loop counter */\n\ |
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| 378 | #\n\ |
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| 379 | # copy the frame\n\ |
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| 380 | saveFrameLoop:\n\ |
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| 381 | move.w (%sp)+,(%a1)+\n\ |
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| 382 | dbf %d0,saveFrameLoop\n\ |
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| 383 | #\n\ |
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| 384 | # now that the stack has been clenaed,\n\ |
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| 385 | # save the a7 in use at time of exception\n\ |
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| 386 | move.l %sp,superStack /* save supervisor sp */\n\ |
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| 387 | andi.w #0x2000,%d1 /* were we in supervisor mode ? */\n\ |
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| 388 | beq userMode \n\ |
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| 389 | move.l %a7,60(%a5) /* save a7 */\n\ |
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| 390 | bra a7saveDone\n\ |
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| 391 | userMode: \n\ |
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| 392 | move.l %usp,%a1 \n\ |
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| 393 | move.l %a1,60(%a5) /* save user stack pointer */\n\ |
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| 394 | a7saveDone:\n\ |
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| 395 | \n\ |
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| 396 | #\n\ |
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| 397 | # save size of frame\n\ |
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| 398 | move.w %d3,-(%a0)\n\ |
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| 399 | \n\ |
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| 400 | move.l %d2,-(%a0) /* save vector number */\n\ |
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| 401 | #\n\ |
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| 402 | # save pc causing exception\n\ |
---|
| 403 | move.l %a4,-(%a0)\n\ |
---|
| 404 | #\n\ |
---|
| 405 | # save old frame link and set the new value\n\ |
---|
| 406 | move.l lastFrame,%a1 /* last frame pointer */\n\ |
---|
| 407 | move.l %a1,-(%a0) /* save pointer to prev frame */\n\ |
---|
| 408 | move.l %a0,lastFrame\n\ |
---|
| 409 | \n\ |
---|
| 410 | move.l %d2,-(%sp) /* push exception num */\n\ |
---|
| 411 | move.l exceptionHook,%a0 /* get address of handler */\n\ |
---|
| 412 | jbsr (%a0) /* and call it */\n\ |
---|
| 413 | clr.l (%sp) /* replace exception num parm with frame ptr */\n\ |
---|
| 414 | jbsr _returnFromException /* jbsr, but never returns */\n\ |
---|
[219bb18] | 415 | "); |
---|
[a8d953f] | 416 | #else /* mc68000 */ |
---|
| 417 | /* This function is called when an exception occurs. It translates the |
---|
| 418 | * return address found on the stack into an exception vector # which |
---|
| 419 | * is then handled by either handle_exception or a system handler. |
---|
[6128a4a] | 420 | * _catchException provides a front end for both. |
---|
[a8d953f] | 421 | * |
---|
| 422 | * stack on entry: stack on exit: |
---|
[6128a4a] | 423 | * Program counter MSWord exception # MSWord |
---|
[a8d953f] | 424 | * Program counter LSWord exception # MSWord |
---|
[6128a4a] | 425 | * Status Register |
---|
| 426 | * Return Address MSWord |
---|
| 427 | * Return Address LSWord |
---|
[a8d953f] | 428 | */ |
---|
[7922b39c] | 429 | __asm__ ("\n\ |
---|
[ee55cdb] | 430 | .text\n\ |
---|
| 431 | .globl _catchException\n\ |
---|
[a8d953f] | 432 | _catchException:"); |
---|
| 433 | DISABLE_INTERRUPTS(); |
---|
[7922b39c] | 434 | __asm__ ("\ |
---|
[a8d953f] | 435 | moveml %d0-%d7/%a0-%a6,registers /* save registers */ \n\ |
---|
| 436 | movel lastFrame,%a0 /* last frame pointer */ \n\ |
---|
| 437 | "); |
---|
[6128a4a] | 438 | SAVE_FP_REGS(); |
---|
[7922b39c] | 439 | __asm__ (" \n\ |
---|
[a8d953f] | 440 | lea registers,%a5 /* get address of registers */ \n\ |
---|
| 441 | movel (%sp)+,%d2 /* pop return address */ \n\ |
---|
| 442 | addl #1530,%d2 /* convert return addr to */ \n\ |
---|
| 443 | divs #6,%d2 /* exception number */ \n\ |
---|
| 444 | extl %d2 \n\ |
---|
| 445 | \n\ |
---|
| 446 | moveql #3,%d3 /* assume a three word frame */ \n\ |
---|
| 447 | \n\ |
---|
| 448 | cmpiw #3,%d2 /* bus error or address error ? */ \n\ |
---|
| 449 | bgt normal /* if >3 then normal error */ \n\ |
---|
| 450 | movel (%sp)+,-(%a0) /* copy error info to frame buff*/ \n\ |
---|
| 451 | movel (%sp)+,-(%a0) /* these are never used */ \n\ |
---|
| 452 | moveql #7,%d3 /* this is a 7 word frame */ \n\ |
---|
| 453 | \n\ |
---|
| 454 | normal: \n\ |
---|
| 455 | movew (%sp)+,%d1 /* pop status register */ \n\ |
---|
| 456 | movel (%sp)+,%a4 /* pop program counter */ \n\ |
---|
| 457 | movew %d1,66(%a5) /* save sr */ \n\ |
---|
| 458 | movel %a4,68(%a5) /* save pc in _regisers[] */ \n\ |
---|
| 459 | movel %a4,-(%a0) /* copy pc to frame buffer */ \n\ |
---|
| 460 | movew %d1,-(%a0) /* copy sr to frame buffer */ \n\ |
---|
| 461 | \n\ |
---|
| 462 | movel %sp,superStack /* save supervisor sp */ \n\ |
---|
| 463 | \n\ |
---|
| 464 | andiw #0x2000,%d1 /* were we in supervisor mode ? */ \n\ |
---|
| 465 | beq userMode \n\ |
---|
| 466 | movel %a7,60(%a5) /* save a7 */ \n\ |
---|
| 467 | bra saveDone \n\ |
---|
| 468 | userMode: \n\ |
---|
| 469 | movel %usp,%a1 /* save user stack pointer */ \n\ |
---|
| 470 | movel %a1,60(%a5) /* save user stack pointer */ \n\ |
---|
| 471 | saveDone: \n\ |
---|
| 472 | \n\ |
---|
| 473 | movew %d3,-(%a0) /* push frame size in words */ \n\ |
---|
| 474 | movel %d2,-(%a0) /* push vector number */ \n\ |
---|
| 475 | movel %a4,-(%a0) /* push exception pc */ \n\ |
---|
| 476 | \n\ |
---|
| 477 | # \n\ |
---|
| 478 | # save old frame link and set the new value \n\ |
---|
| 479 | movel _lastFrame,%a1 /* last frame pointer */ \n\ |
---|
| 480 | movel %a1,-(%a0) /* save pointer to prev frame */ \n\ |
---|
| 481 | movel %a0,lastFrame \n\ |
---|
| 482 | \n\ |
---|
| 483 | movel %d2,-(%sp) /* push exception num */ \n\ |
---|
| 484 | movel exceptionHook,%a0 /* get address of handler */ \n\ |
---|
| 485 | jbsr (%a0) /* and call it */ \n\ |
---|
| 486 | clrl (%sp) /* replace exception num parm with frame ptr */ \n\ |
---|
| 487 | jbsr _returnFromException /* jbsr, but never returns */ \n\ |
---|
| 488 | "); |
---|
| 489 | #endif |
---|
| 490 | |
---|
| 491 | /* |
---|
| 492 | * remcomHandler is a front end for handle_exception. It moves the |
---|
| 493 | * stack pointer into an area reserved for debugger use in case the |
---|
| 494 | * breakpoint happened in supervisor mode. |
---|
| 495 | */ |
---|
[7922b39c] | 496 | __asm__ ("remcomHandler:"); |
---|
| 497 | __asm__ (" add.l #4,%sp"); /* pop off return address */ |
---|
| 498 | __asm__ (" move.l (%sp)+,%d0"); /* get the exception number */ |
---|
| 499 | __asm__ (" move.l stackPtr,%sp"); /* move to remcom stack area */ |
---|
| 500 | __asm__ (" move.l %d0,-(%sp)"); /* push exception onto stack */ |
---|
| 501 | __asm__ (" jbsr handle_exception"); /* this never returns */ |
---|
| 502 | __asm__ (" rts"); /* return */ |
---|
[a8d953f] | 503 | } /* end of stub_dummy_asm_wrapper function */ |
---|
| 504 | |
---|
| 505 | void _returnFromException( Frame *frame ) |
---|
| 506 | { |
---|
| 507 | /* if no passed in frame, use the last one */ |
---|
| 508 | if (! frame) |
---|
| 509 | { |
---|
| 510 | frame = lastFrame; |
---|
| 511 | frame->frameSize = 4; |
---|
| 512 | frame->format = 0; |
---|
| 513 | frame->fsaveHeader = -1; /* restore regs, but we dont have fsave info*/ |
---|
| 514 | } |
---|
| 515 | |
---|
| 516 | #if !M68K_HAS_VBR |
---|
| 517 | /* a 68000 cannot use the internal info pushed onto a bus error |
---|
| 518 | * or address error frame when doing an RTE so don't put this info |
---|
| 519 | * onto the stack or the stack will creep every time this happens. |
---|
| 520 | */ |
---|
| 521 | frame->frameSize=3; |
---|
| 522 | #endif |
---|
| 523 | |
---|
| 524 | /* throw away any frames in the list after this frame */ |
---|
| 525 | lastFrame = frame; |
---|
| 526 | |
---|
| 527 | frame->sr = registers[(int) PS]; |
---|
| 528 | frame->pc = registers[(int) PC]; |
---|
| 529 | |
---|
| 530 | if (registers[(int) PS] & 0x2000) |
---|
[6128a4a] | 531 | { |
---|
[a8d953f] | 532 | /* return to supervisor mode... */ |
---|
| 533 | return_to_super(); |
---|
| 534 | } |
---|
| 535 | else |
---|
| 536 | { /* return to user mode */ |
---|
| 537 | return_to_user(); |
---|
| 538 | } |
---|
| 539 | } |
---|
| 540 | |
---|
| 541 | int hex(ch) |
---|
| 542 | char ch; |
---|
| 543 | { |
---|
| 544 | if ((ch >= 'a') && (ch <= 'f')) return (ch-'a'+10); |
---|
| 545 | if ((ch >= '0') && (ch <= '9')) return (ch-'0'); |
---|
| 546 | if ((ch >= 'A') && (ch <= 'F')) return (ch-'A'+10); |
---|
| 547 | return (-1); |
---|
| 548 | } |
---|
| 549 | |
---|
| 550 | /* scan for the sequence $<data>#<checksum> */ |
---|
| 551 | void getpacket(buffer) |
---|
| 552 | char * buffer; |
---|
| 553 | { |
---|
| 554 | unsigned char checksum; |
---|
| 555 | unsigned char xmitcsum; |
---|
| 556 | int i; |
---|
| 557 | int count; |
---|
| 558 | char ch; |
---|
[6128a4a] | 559 | |
---|
[a8d953f] | 560 | do { |
---|
| 561 | /* wait around for the start character, ignore all other characters */ |
---|
[6128a4a] | 562 | while ((ch = getDebugChar()) != '$'); |
---|
[a8d953f] | 563 | checksum = 0; |
---|
| 564 | xmitcsum = -1; |
---|
[6128a4a] | 565 | |
---|
[a8d953f] | 566 | count = 0; |
---|
[6128a4a] | 567 | |
---|
[a8d953f] | 568 | /* now, read until a # or end of buffer is found */ |
---|
| 569 | while (count < BUFMAX) { |
---|
| 570 | ch = getDebugChar(); |
---|
| 571 | if (ch == '#') break; |
---|
| 572 | checksum = checksum + ch; |
---|
| 573 | buffer[count] = ch; |
---|
| 574 | count = count + 1; |
---|
| 575 | } |
---|
| 576 | buffer[count] = 0; |
---|
| 577 | |
---|
| 578 | if (ch == '#') { |
---|
| 579 | xmitcsum = hex(getDebugChar()) << 4; |
---|
| 580 | xmitcsum += hex(getDebugChar()); |
---|
| 581 | if ((remote_debug ) && (checksum != xmitcsum)) { |
---|
| 582 | fprintf (stderr,"bad checksum. My count = 0x%x, sent=0x%x. buf=%s\n", |
---|
| 583 | checksum,xmitcsum,buffer); |
---|
| 584 | } |
---|
[6128a4a] | 585 | |
---|
| 586 | if (checksum != xmitcsum) putDebugChar('-'); /* failed checksum */ |
---|
[a8d953f] | 587 | else { |
---|
| 588 | putDebugChar('+'); /* successful transfer */ |
---|
| 589 | /* if a sequence char is present, reply the sequence ID */ |
---|
| 590 | if (buffer[2] == ':') { |
---|
| 591 | putDebugChar( buffer[0] ); |
---|
| 592 | putDebugChar( buffer[1] ); |
---|
| 593 | /* remove sequence chars from buffer */ |
---|
| 594 | count = strlen(buffer); |
---|
| 595 | for (i=3; i <= count; i++) buffer[i-3] = buffer[i]; |
---|
[6128a4a] | 596 | } |
---|
| 597 | } |
---|
| 598 | } |
---|
[a8d953f] | 599 | } while (checksum != xmitcsum); |
---|
[6128a4a] | 600 | |
---|
[a8d953f] | 601 | } |
---|
| 602 | |
---|
[6128a4a] | 603 | /* send the packet in buffer. The host get's one chance to read it. |
---|
[a8d953f] | 604 | This routine does not wait for a positive acknowledge. */ |
---|
| 605 | |
---|
| 606 | /* |
---|
| 607 | * Send the packet in buffer and wait for a positive acknowledgement. |
---|
| 608 | */ |
---|
| 609 | static void |
---|
| 610 | putpacket (char *buffer) |
---|
| 611 | { |
---|
| 612 | int checksum; |
---|
| 613 | |
---|
| 614 | /* $<packet info>#<checksum> */ |
---|
| 615 | do |
---|
| 616 | { |
---|
| 617 | char *src = buffer; |
---|
| 618 | putDebugChar ('$'); |
---|
| 619 | checksum = 0; |
---|
| 620 | |
---|
| 621 | while (*src != '\0') |
---|
| 622 | { |
---|
| 623 | int runlen = 0; |
---|
| 624 | |
---|
| 625 | /* Do run length encoding */ |
---|
| 626 | while ((src[runlen] == src[0]) && (runlen < 99)) |
---|
| 627 | runlen++; |
---|
| 628 | if (runlen > 3) |
---|
| 629 | { |
---|
| 630 | int encode; |
---|
| 631 | /* Got a useful amount */ |
---|
| 632 | putDebugChar (*src); |
---|
| 633 | checksum += *src; |
---|
| 634 | putDebugChar ('*'); |
---|
| 635 | checksum += '*'; |
---|
| 636 | checksum += (encode = (runlen - 4) + ' '); |
---|
| 637 | putDebugChar (encode); |
---|
| 638 | src += runlen; |
---|
| 639 | } |
---|
| 640 | else |
---|
| 641 | { |
---|
| 642 | putDebugChar (*src); |
---|
| 643 | checksum += *src; |
---|
| 644 | src++; |
---|
| 645 | } |
---|
| 646 | } |
---|
| 647 | |
---|
| 648 | putDebugChar ('#'); |
---|
| 649 | putDebugChar (highhex (checksum)); |
---|
| 650 | putDebugChar (lowhex (checksum)); |
---|
| 651 | } |
---|
| 652 | while (getDebugChar () != '+'); |
---|
| 653 | } |
---|
| 654 | |
---|
| 655 | char remcomInBuffer[BUFMAX]; |
---|
| 656 | char remcomOutBuffer[BUFMAX]; |
---|
| 657 | static short error; |
---|
| 658 | |
---|
[ee55cdb] | 659 | void debug_error( |
---|
[219bb18] | 660 | char * format, |
---|
| 661 | char * parm |
---|
[ee55cdb] | 662 | ) |
---|
[a8d953f] | 663 | { |
---|
| 664 | if (remote_debug) fprintf (stderr,format,parm); |
---|
| 665 | } |
---|
| 666 | |
---|
| 667 | /* convert the memory pointed to by mem into hex, placing result in buf */ |
---|
| 668 | /* return a pointer to the last char put in buf (null) */ |
---|
| 669 | char* mem2hex(mem, buf, count) |
---|
| 670 | char* mem; |
---|
| 671 | char* buf; |
---|
| 672 | int count; |
---|
| 673 | { |
---|
| 674 | int i; |
---|
| 675 | unsigned char ch; |
---|
| 676 | for (i=0;i<count;i++) { |
---|
| 677 | ch = *mem++; |
---|
| 678 | *buf++ = gdb_hexchars[ch >> 4]; |
---|
| 679 | *buf++ = gdb_hexchars[ch % 16]; |
---|
| 680 | } |
---|
[6128a4a] | 681 | *buf = 0; |
---|
[a8d953f] | 682 | return(buf); |
---|
| 683 | } |
---|
| 684 | |
---|
| 685 | /* convert the hex array pointed to by buf into binary to be placed in mem */ |
---|
| 686 | /* return a pointer to the character AFTER the last byte written */ |
---|
| 687 | char* hex2mem(buf, mem, count) |
---|
| 688 | char* buf; |
---|
| 689 | char* mem; |
---|
| 690 | int count; |
---|
| 691 | { |
---|
| 692 | int i; |
---|
| 693 | unsigned char ch; |
---|
| 694 | for (i=0;i<count;i++) { |
---|
| 695 | ch = hex(*buf++) << 4; |
---|
| 696 | ch = ch + hex(*buf++); |
---|
| 697 | *mem++ = ch; |
---|
| 698 | } |
---|
| 699 | return(mem); |
---|
| 700 | } |
---|
| 701 | |
---|
| 702 | /* Convert the binary stream in BUF to memory. |
---|
| 703 | |
---|
| 704 | Gdb will escape $, #, and the escape char (0x7d). |
---|
| 705 | COUNT is the total number of bytes to write into |
---|
| 706 | memory. */ |
---|
| 707 | static unsigned char * |
---|
| 708 | bin2mem ( |
---|
| 709 | unsigned char *buf, |
---|
| 710 | unsigned char *mem, |
---|
| 711 | int count |
---|
| 712 | ) |
---|
| 713 | { |
---|
| 714 | int i; |
---|
| 715 | |
---|
| 716 | for (i = 0; i < count; i++) { |
---|
| 717 | /* Check for any escaped characters. Be paranoid and |
---|
| 718 | only unescape chars that should be escaped. */ |
---|
| 719 | if (*buf == 0x7d) { |
---|
| 720 | switch (*(buf+1)) { |
---|
| 721 | case 0x3: /* # */ |
---|
| 722 | case 0x4: /* $ */ |
---|
| 723 | case 0x5d: /* escape char */ |
---|
| 724 | buf++; |
---|
| 725 | *buf |= 0x20; |
---|
| 726 | break; |
---|
| 727 | default: |
---|
| 728 | /* nothing */ |
---|
| 729 | break; |
---|
| 730 | } |
---|
| 731 | } |
---|
| 732 | |
---|
| 733 | *mem++ = *buf++; |
---|
| 734 | } |
---|
| 735 | |
---|
| 736 | return mem; |
---|
| 737 | } |
---|
| 738 | |
---|
| 739 | /* a bus error has occurred, perform a longjmp |
---|
| 740 | to return execution and allow handling of the error */ |
---|
| 741 | |
---|
| 742 | void handle_buserror() |
---|
| 743 | { |
---|
| 744 | longjmp(remcomEnv,1); |
---|
| 745 | } |
---|
| 746 | |
---|
[6128a4a] | 747 | /* this function takes the 68000 exception number and attempts to |
---|
[a8d953f] | 748 | translate this number into a unix compatible signal value */ |
---|
| 749 | int computeSignal( exceptionVector ) |
---|
| 750 | int exceptionVector; |
---|
| 751 | { |
---|
| 752 | int sigval; |
---|
| 753 | switch (exceptionVector) { |
---|
| 754 | case 2 : sigval = 10; break; /* bus error */ |
---|
| 755 | case 3 : sigval = 10; break; /* address error */ |
---|
| 756 | case 4 : sigval = 4; break; /* illegal instruction */ |
---|
| 757 | case 5 : sigval = 8; break; /* zero divide */ |
---|
| 758 | case 6 : sigval = 8; break; /* chk instruction */ |
---|
| 759 | case 7 : sigval = 8; break; /* trapv instruction */ |
---|
| 760 | case 8 : sigval = 11; break; /* privilege violation */ |
---|
| 761 | case 9 : sigval = 5; break; /* trace trap */ |
---|
| 762 | case 10: sigval = 4; break; /* line 1010 emulator */ |
---|
| 763 | case 11: sigval = 4; break; /* line 1111 emulator */ |
---|
| 764 | |
---|
| 765 | /* Coprocessor protocol violation. Using a standard MMU or FPU |
---|
| 766 | this cannot be triggered by software. Call it a SIGBUS. */ |
---|
| 767 | case 13: sigval = 10; break; |
---|
| 768 | |
---|
| 769 | case 31: sigval = 2; break; /* interrupt */ |
---|
| 770 | case 33: sigval = 5; break; /* GDB breakpoint */ |
---|
| 771 | case 34: sigval = 5; break; /* coded breakpoint */ |
---|
| 772 | |
---|
| 773 | /* This is a trap #8 instruction. Apparently it is someone's software |
---|
| 774 | convention for some sort of SIGFPE condition. Whose? How many |
---|
| 775 | people are being screwed by having this code the way it is? |
---|
| 776 | Is there a clean solution? */ |
---|
| 777 | case 40: sigval = 8; break; /* floating point err */ |
---|
| 778 | |
---|
| 779 | case 48: sigval = 8; break; /* floating point err */ |
---|
| 780 | case 49: sigval = 8; break; /* floating point err */ |
---|
| 781 | case 50: sigval = 8; break; /* zero divide */ |
---|
| 782 | case 51: sigval = 8; break; /* underflow */ |
---|
| 783 | case 52: sigval = 8; break; /* operand error */ |
---|
| 784 | case 53: sigval = 8; break; /* overflow */ |
---|
| 785 | case 54: sigval = 8; break; /* NAN */ |
---|
[6128a4a] | 786 | default: |
---|
[a8d953f] | 787 | sigval = 7; /* "software generated"*/ |
---|
| 788 | } |
---|
| 789 | return (sigval); |
---|
| 790 | } |
---|
| 791 | |
---|
| 792 | /**********************************************/ |
---|
| 793 | /* WHILE WE FIND NICE HEX CHARS, BUILD AN INT */ |
---|
| 794 | /* RETURN NUMBER OF CHARS PROCESSED */ |
---|
| 795 | /**********************************************/ |
---|
| 796 | int hexToInt(char **ptr, int *intValue) |
---|
| 797 | { |
---|
| 798 | int numChars = 0; |
---|
| 799 | int hexValue; |
---|
[6128a4a] | 800 | |
---|
[a8d953f] | 801 | *intValue = 0; |
---|
| 802 | |
---|
| 803 | while (**ptr) |
---|
| 804 | { |
---|
| 805 | hexValue = hex(**ptr); |
---|
| 806 | if (hexValue >=0) |
---|
| 807 | { |
---|
| 808 | *intValue = (*intValue <<4) | hexValue; |
---|
| 809 | numChars ++; |
---|
| 810 | } |
---|
| 811 | else |
---|
| 812 | break; |
---|
[6128a4a] | 813 | |
---|
[a8d953f] | 814 | (*ptr)++; |
---|
| 815 | } |
---|
| 816 | |
---|
| 817 | return (numChars); |
---|
| 818 | } |
---|
| 819 | |
---|
| 820 | /* |
---|
| 821 | * This support function prepares and sends the message containing the |
---|
| 822 | * basic information about this exception. |
---|
| 823 | */ |
---|
| 824 | |
---|
| 825 | void gdb_stub_report_exception_info( |
---|
| 826 | int vector, |
---|
| 827 | int *regs, |
---|
| 828 | int thread |
---|
| 829 | ) |
---|
| 830 | { |
---|
| 831 | char *optr; |
---|
| 832 | int sigval; |
---|
| 833 | |
---|
| 834 | optr = remcomOutBuffer; |
---|
| 835 | *optr++ = 'T'; |
---|
| 836 | sigval = computeSignal (vector); |
---|
| 837 | *optr++ = highhex (sigval); |
---|
| 838 | *optr++ = lowhex (sigval); |
---|
| 839 | |
---|
| 840 | *optr++ = highhex(A7); |
---|
| 841 | *optr++ = lowhex(A7); |
---|
| 842 | *optr++ = ':'; |
---|
[6128a4a] | 843 | optr = mem2hstr(optr, |
---|
| 844 | (unsigned char *)&(regs[A7]), |
---|
[a8d953f] | 845 | sizeof(regs[A7])); |
---|
| 846 | *optr++ = ';'; |
---|
[6128a4a] | 847 | |
---|
[a8d953f] | 848 | *optr++ = highhex(PC); |
---|
| 849 | *optr++ = lowhex(PC); |
---|
| 850 | *optr++ = ':'; |
---|
[6128a4a] | 851 | optr = mem2hstr(optr, |
---|
| 852 | (unsigned char *)&(regs[PC]), |
---|
[a8d953f] | 853 | sizeof(regs[PC]) ); |
---|
| 854 | *optr++ = ';'; |
---|
| 855 | |
---|
| 856 | #if defined(GDB_STUB_ENABLE_THREAD_SUPPORT) |
---|
[6128a4a] | 857 | if (do_threads) |
---|
[a8d953f] | 858 | { |
---|
| 859 | *optr++ = 't'; |
---|
| 860 | *optr++ = 'h'; |
---|
| 861 | *optr++ = 'r'; |
---|
| 862 | *optr++ = 'e'; |
---|
| 863 | *optr++ = 'a'; |
---|
| 864 | *optr++ = 'd'; |
---|
| 865 | *optr++ = ':'; |
---|
| 866 | optr = thread2vhstr(optr, thread); |
---|
| 867 | *optr++ = ';'; |
---|
| 868 | } |
---|
| 869 | #endif |
---|
| 870 | *optr++ = '\0'; |
---|
| 871 | } |
---|
| 872 | |
---|
| 873 | /* |
---|
| 874 | * This function does all command procesing for interfacing to gdb. |
---|
| 875 | */ |
---|
| 876 | void handle_exception(int exceptionVector) |
---|
| 877 | { |
---|
| 878 | int host_has_detached = 0; |
---|
| 879 | int addr, length; |
---|
| 880 | char * ptr; |
---|
| 881 | int newPC; |
---|
| 882 | Frame *frame; |
---|
| 883 | int current_thread; /* current generic thread */ |
---|
| 884 | int thread; /* stopped thread: context exception happened in */ |
---|
| 885 | void *regptr; |
---|
| 886 | int binary; |
---|
| 887 | |
---|
[6128a4a] | 888 | if (remote_debug) printf("vector=%d, sr=0x%x, pc=0x%x\n", |
---|
[a8d953f] | 889 | exceptionVector, |
---|
[6128a4a] | 890 | registers[ PS ], |
---|
[a8d953f] | 891 | registers[ PC ]); |
---|
| 892 | |
---|
| 893 | thread = 0; |
---|
| 894 | #if defined(GDB_STUB_ENABLE_THREAD_SUPPORT) |
---|
| 895 | if (do_threads) { |
---|
| 896 | thread = rtems_gdb_stub_get_current_thread(); |
---|
| 897 | } |
---|
| 898 | #endif |
---|
| 899 | current_thread = thread; |
---|
[6128a4a] | 900 | |
---|
[a8d953f] | 901 | #if 0 |
---|
| 902 | /* reply to host that an exception has occurred */ |
---|
| 903 | sigval = computeSignal( exceptionVector ); |
---|
| 904 | remcomOutBuffer[0] = 'S'; |
---|
| 905 | remcomOutBuffer[1] = gdb_hexchars[sigval >> 4]; |
---|
| 906 | remcomOutBuffer[2] = gdb_hexchars[sigval % 16]; |
---|
| 907 | remcomOutBuffer[3] = 0; |
---|
| 908 | #else |
---|
| 909 | /* reply to host that an exception has occurred with some basic info */ |
---|
| 910 | gdb_stub_report_exception_info(exceptionVector, registers, thread); |
---|
| 911 | #endif |
---|
| 912 | |
---|
[6128a4a] | 913 | putpacket(remcomOutBuffer); |
---|
[a8d953f] | 914 | |
---|
[6128a4a] | 915 | while (!(host_has_detached)) { |
---|
[a8d953f] | 916 | binary = 0; |
---|
| 917 | error = 0; |
---|
| 918 | remcomOutBuffer[0] = 0; |
---|
| 919 | getpacket(remcomInBuffer); |
---|
| 920 | switch (remcomInBuffer[0]) { |
---|
| 921 | #if 0 |
---|
| 922 | case '?' : remcomOutBuffer[0] = 'S'; |
---|
| 923 | remcomOutBuffer[1] = gdb_hexchars[sigval >> 4]; |
---|
| 924 | remcomOutBuffer[2] = gdb_hexchars[sigval % 16]; |
---|
| 925 | remcomOutBuffer[3] = 0; |
---|
[6128a4a] | 926 | break; |
---|
[a8d953f] | 927 | #else |
---|
| 928 | case '?' : gdb_stub_report_exception_info(exceptionVector, |
---|
| 929 | registers, |
---|
| 930 | thread); |
---|
| 931 | break; |
---|
| 932 | #endif |
---|
| 933 | case 'd' : remote_debug = !(remote_debug); /* toggle debug flag */ |
---|
[6128a4a] | 934 | break; |
---|
[a8d953f] | 935 | case 'D' : /* host has detached */ |
---|
| 936 | strcpy(remcomOutBuffer,"OK"); |
---|
| 937 | host_has_detached = 1; |
---|
[6128a4a] | 938 | break; |
---|
[a8d953f] | 939 | case 'g': /* return the values of the CPU registers */ |
---|
| 940 | regptr = registers; |
---|
| 941 | #if defined(GDB_STUB_ENABLE_THREAD_SUPPORT) |
---|
| 942 | if (do_threads && current_thread != thread ) |
---|
| 943 | regptr = ¤t_thread_registers; |
---|
| 944 | #endif |
---|
| 945 | mem2hex (regptr, remcomOutBuffer, sizeof registers); |
---|
| 946 | break; |
---|
| 947 | |
---|
| 948 | case 'G': /* set the values of the CPU registers - return OK */ |
---|
| 949 | regptr = registers; |
---|
| 950 | #if defined(GDB_STUB_ENABLE_THREAD_SUPPORT) |
---|
| 951 | if (do_threads && current_thread != thread ) |
---|
| 952 | regptr = ¤t_thread_registers; |
---|
| 953 | #endif |
---|
[6128a4a] | 954 | if (hex2mem (&remcomInBuffer[1], |
---|
| 955 | regptr, |
---|
[a8d953f] | 956 | sizeof registers)) { |
---|
| 957 | strcpy (remcomOutBuffer, "OK"); |
---|
| 958 | } |
---|
| 959 | else { |
---|
| 960 | strcpy (remcomOutBuffer, "E00"); /* E00 = bad "set register" command */ |
---|
| 961 | } |
---|
| 962 | break; |
---|
[6128a4a] | 963 | |
---|
[a8d953f] | 964 | /* mAA..AA,LLLL Read LLLL bytes at address AA..AA */ |
---|
[6128a4a] | 965 | case 'm' : |
---|
[a8d953f] | 966 | if (setjmp(remcomEnv) == 0) |
---|
| 967 | { |
---|
[6128a4a] | 968 | m68k_exceptionHandler(2,handle_buserror); |
---|
[a8d953f] | 969 | |
---|
| 970 | /* TRY TO READ %x,%x. IF SUCCEED, SET PTR = 0 */ |
---|
| 971 | ptr = &remcomInBuffer[1]; |
---|
| 972 | if (hexToInt(&ptr,&addr)) |
---|
| 973 | if (*(ptr++) == ',') |
---|
[6128a4a] | 974 | if (hexToInt(&ptr,&length)) |
---|
[a8d953f] | 975 | { |
---|
| 976 | ptr = 0; |
---|
| 977 | mem2hex((char*) addr, remcomOutBuffer, length); |
---|
| 978 | } |
---|
| 979 | |
---|
| 980 | if (ptr) |
---|
| 981 | { |
---|
| 982 | strcpy(remcomOutBuffer,"E01"); |
---|
| 983 | debug_error("malformed read memory command: %s",remcomInBuffer); |
---|
[6128a4a] | 984 | } |
---|
| 985 | } |
---|
[a8d953f] | 986 | else { |
---|
[6128a4a] | 987 | m68k_exceptionHandler(2,_catchException); |
---|
[a8d953f] | 988 | strcpy(remcomOutBuffer,"E03"); |
---|
[219bb18] | 989 | debug_error("bus error", 0); |
---|
[6128a4a] | 990 | } |
---|
| 991 | |
---|
[a8d953f] | 992 | /* restore handler for bus error */ |
---|
[6128a4a] | 993 | m68k_exceptionHandler(2,_catchException); |
---|
[a8d953f] | 994 | break; |
---|
[6128a4a] | 995 | |
---|
[a8d953f] | 996 | /* XAA..AA,LLLL: Write LLLL bytes at address AA.AA return OK */ |
---|
| 997 | /* Transfer is in binary, '$', '#' and 0x7d is escaped with 0x7d */ |
---|
[6128a4a] | 998 | case 'X' : |
---|
[a8d953f] | 999 | binary = 1; |
---|
| 1000 | /* MAA..AA,LLLL: Write LLLL bytes at address AA.AA return OK */ |
---|
[6128a4a] | 1001 | case 'M' : |
---|
[a8d953f] | 1002 | if (setjmp(remcomEnv) == 0) { |
---|
[6128a4a] | 1003 | m68k_exceptionHandler(2,handle_buserror); |
---|
| 1004 | |
---|
[a8d953f] | 1005 | /* TRY TO READ '%x,%x:'. IF SUCCEED, SET PTR = 0 */ |
---|
| 1006 | ptr = &remcomInBuffer[1]; |
---|
| 1007 | if (hexToInt(&ptr,&addr)) |
---|
| 1008 | if (*(ptr++) == ',') |
---|
| 1009 | if (hexToInt(&ptr,&length)) |
---|
| 1010 | if (*(ptr++) == ':') |
---|
| 1011 | { |
---|
| 1012 | if (binary) { |
---|
| 1013 | bin2mem(ptr,(char *)addr,length); |
---|
| 1014 | } |
---|
| 1015 | else { |
---|
| 1016 | hex2mem(ptr, (char*) addr, length); |
---|
| 1017 | } |
---|
| 1018 | ptr = 0; |
---|
| 1019 | strcpy(remcomOutBuffer,"OK"); |
---|
| 1020 | } |
---|
| 1021 | if (ptr) |
---|
| 1022 | { |
---|
| 1023 | strcpy(remcomOutBuffer,"E02"); |
---|
| 1024 | debug_error("malformed write memory command: %s",remcomInBuffer); |
---|
[6128a4a] | 1025 | } |
---|
| 1026 | } |
---|
[a8d953f] | 1027 | else { |
---|
[6128a4a] | 1028 | m68k_exceptionHandler(2,_catchException); |
---|
[a8d953f] | 1029 | strcpy(remcomOutBuffer,"E03"); |
---|
[219bb18] | 1030 | debug_error("bus error", 0); |
---|
[6128a4a] | 1031 | } |
---|
[a8d953f] | 1032 | |
---|
| 1033 | /* restore handler for bus error */ |
---|
[6128a4a] | 1034 | m68k_exceptionHandler(2,_catchException); |
---|
[a8d953f] | 1035 | break; |
---|
| 1036 | |
---|
| 1037 | /* cAA..AA Continue at address AA..AA(optional) */ |
---|
| 1038 | /* sAA..AA Step one instruction from AA..AA(optional) */ |
---|
[6128a4a] | 1039 | case 'c' : |
---|
| 1040 | case 's' : |
---|
[a8d953f] | 1041 | /* try to read optional parameter, pc unchanged if no parm */ |
---|
| 1042 | ptr = &remcomInBuffer[1]; |
---|
| 1043 | if (hexToInt(&ptr,&addr)) |
---|
| 1044 | registers[ PC ] = addr; |
---|
[6128a4a] | 1045 | |
---|
[a8d953f] | 1046 | newPC = registers[ PC]; |
---|
[6128a4a] | 1047 | |
---|
[a8d953f] | 1048 | /* clear the trace bit */ |
---|
| 1049 | registers[ PS ] &= 0x7fff; |
---|
[6128a4a] | 1050 | |
---|
[a8d953f] | 1051 | /* set the trace bit if we're stepping */ |
---|
| 1052 | if (remcomInBuffer[0] == 's') registers[ PS ] |= 0x8000; |
---|
[6128a4a] | 1053 | |
---|
[a8d953f] | 1054 | /* |
---|
| 1055 | * look for newPC in the linked list of exception frames. |
---|
| 1056 | * if it is found, use the old frame it. otherwise, |
---|
| 1057 | * fake up a dummy frame in returnFromException(). |
---|
| 1058 | */ |
---|
| 1059 | if (remote_debug) printf("new pc = 0x%x\n",newPC); |
---|
| 1060 | frame = lastFrame; |
---|
| 1061 | while (frame) |
---|
| 1062 | { |
---|
| 1063 | if (remote_debug) |
---|
| 1064 | printf("frame at 0x%x has pc=0x%x, except#=%d\n", |
---|
[ed9122e] | 1065 | (uint32_t) frame, |
---|
| 1066 | (uint32_t) frame->exceptionPC, |
---|
| 1067 | (uint32_t) frame->exceptionVector); |
---|
[a8d953f] | 1068 | if (frame->exceptionPC == newPC) break; /* bingo! a match */ |
---|
| 1069 | /* |
---|
| 1070 | * for a breakpoint instruction, the saved pc may |
---|
| 1071 | * be off by two due to re-executing the instruction |
---|
| 1072 | * replaced by the trap instruction. Check for this. |
---|
| 1073 | */ |
---|
| 1074 | if ((frame->exceptionVector == 33) && |
---|
| 1075 | (frame->exceptionPC == (newPC+2))) break; |
---|
| 1076 | if (frame == frame->previous) |
---|
| 1077 | { |
---|
[6128a4a] | 1078 | frame = 0; /* no match found */ |
---|
| 1079 | break; |
---|
[a8d953f] | 1080 | } |
---|
| 1081 | frame = frame->previous; |
---|
| 1082 | } |
---|
[6128a4a] | 1083 | |
---|
[a8d953f] | 1084 | /* |
---|
| 1085 | * If we found a match for the PC AND we are not returning |
---|
| 1086 | * as a result of a breakpoint (33), |
---|
| 1087 | * trace exception (9), nmi (31), jmp to |
---|
| 1088 | * the old exception handler as if this code never ran. |
---|
| 1089 | */ |
---|
[6128a4a] | 1090 | if (frame) |
---|
[a8d953f] | 1091 | { |
---|
[6128a4a] | 1092 | if ((frame->exceptionVector != 9) && |
---|
| 1093 | (frame->exceptionVector != 31) && |
---|
[a8d953f] | 1094 | (frame->exceptionVector != 33)) |
---|
[6128a4a] | 1095 | { |
---|
[a8d953f] | 1096 | /* |
---|
| 1097 | * invoke the previous handler. |
---|
| 1098 | */ |
---|
| 1099 | if (oldExceptionHook) |
---|
| 1100 | (*oldExceptionHook) (frame->exceptionVector); |
---|
| 1101 | newPC = registers[ PC ]; /* pc may have changed */ |
---|
| 1102 | if (newPC != frame->exceptionPC) |
---|
| 1103 | { |
---|
| 1104 | if (remote_debug) |
---|
| 1105 | printf("frame at 0x%x has pc=0x%x, except#=%d\n", |
---|
[ed9122e] | 1106 | (uint32_t) frame, |
---|
[a8d953f] | 1107 | frame->exceptionPC, |
---|
| 1108 | frame->exceptionVector); |
---|
| 1109 | /* re-use the last frame, we're skipping it (longjump?)*/ |
---|
| 1110 | frame = (Frame *) 0; |
---|
| 1111 | _returnFromException( frame ); /* this is a jump */ |
---|
| 1112 | } |
---|
| 1113 | } |
---|
[6128a4a] | 1114 | } |
---|
[a8d953f] | 1115 | |
---|
| 1116 | /* if we couldn't find a frame, create one */ |
---|
| 1117 | if (frame == 0) |
---|
| 1118 | { |
---|
| 1119 | frame = lastFrame -1 ; |
---|
[6128a4a] | 1120 | |
---|
[a8d953f] | 1121 | /* by using a bunch of print commands with breakpoints, |
---|
| 1122 | it's possible for the frame stack to creep down. If it creeps |
---|
| 1123 | too far, give up and reset it to the top. Normal use should |
---|
| 1124 | not see this happen. |
---|
| 1125 | */ |
---|
| 1126 | if ((unsigned int) (frame-2) < (unsigned int) &gdbFrameStack) |
---|
| 1127 | { |
---|
| 1128 | initializeRemcomErrorFrame(); |
---|
[6128a4a] | 1129 | frame = lastFrame; |
---|
[a8d953f] | 1130 | } |
---|
| 1131 | frame->previous = lastFrame; |
---|
| 1132 | lastFrame = frame; |
---|
[6128a4a] | 1133 | frame = 0; /* null so _return... will properly initialize it */ |
---|
| 1134 | } |
---|
| 1135 | |
---|
[a8d953f] | 1136 | _returnFromException( frame ); /* this is a jump */ |
---|
| 1137 | |
---|
| 1138 | break; |
---|
[6128a4a] | 1139 | |
---|
[a8d953f] | 1140 | case 'q': /* queries */ |
---|
| 1141 | #if defined(GDB_STUB_ENABLE_THREAD_SUPPORT) |
---|
[6128a4a] | 1142 | rtems_gdb_process_query( remcomInBuffer, |
---|
| 1143 | remcomOutBuffer, |
---|
| 1144 | do_threads, |
---|
[a8d953f] | 1145 | thread ); |
---|
| 1146 | #endif |
---|
| 1147 | break; |
---|
| 1148 | |
---|
| 1149 | #if defined(GDB_STUB_ENABLE_THREAD_SUPPORT) |
---|
| 1150 | case 'T': |
---|
| 1151 | { |
---|
| 1152 | int testThread; |
---|
| 1153 | |
---|
[6128a4a] | 1154 | if( vhstr2thread(&remcomInBuffer[1], &testThread) == NULL ) |
---|
[a8d953f] | 1155 | { |
---|
| 1156 | strcpy(remcomOutBuffer, "E01"); |
---|
| 1157 | break; |
---|
| 1158 | } |
---|
| 1159 | |
---|
| 1160 | if( rtems_gdb_index_to_stub_id(testThread) == NULL ) |
---|
| 1161 | { |
---|
| 1162 | strcpy(remcomOutBuffer, "E02"); |
---|
| 1163 | } |
---|
| 1164 | else |
---|
| 1165 | { |
---|
| 1166 | strcpy(remcomOutBuffer, "OK"); |
---|
| 1167 | } |
---|
| 1168 | } |
---|
| 1169 | break; |
---|
| 1170 | #endif |
---|
[6128a4a] | 1171 | |
---|
[a8d953f] | 1172 | case 'H': /* set new thread */ |
---|
| 1173 | #if defined(GDB_STUB_ENABLE_THREAD_SUPPORT) |
---|
| 1174 | if (remcomInBuffer[1] != 'g') { |
---|
| 1175 | break; |
---|
| 1176 | } |
---|
[6128a4a] | 1177 | |
---|
[a8d953f] | 1178 | if (!do_threads) { |
---|
| 1179 | break; |
---|
| 1180 | } |
---|
[6128a4a] | 1181 | |
---|
[a8d953f] | 1182 | { |
---|
| 1183 | int tmp, ret; |
---|
[6128a4a] | 1184 | |
---|
[a8d953f] | 1185 | /* Set new generic thread */ |
---|
| 1186 | if (vhstr2thread(&remcomInBuffer[2], &tmp) == NULL) { |
---|
| 1187 | strcpy(remcomOutBuffer, "E01"); |
---|
| 1188 | break; |
---|
| 1189 | } |
---|
| 1190 | |
---|
| 1191 | /* 0 means `thread' */ |
---|
| 1192 | if (tmp == 0) { |
---|
| 1193 | tmp = thread; |
---|
| 1194 | } |
---|
| 1195 | |
---|
| 1196 | if (tmp == current_thread) { |
---|
| 1197 | /* No changes */ |
---|
| 1198 | strcpy(remcomOutBuffer, "OK"); |
---|
| 1199 | break; |
---|
| 1200 | } |
---|
| 1201 | |
---|
[6128a4a] | 1202 | /* Save current thread registers if necessary */ |
---|
[a8d953f] | 1203 | if (current_thread != thread) { |
---|
| 1204 | ret = rtems_gdb_stub_set_thread_regs( |
---|
| 1205 | current_thread, (unsigned int *) ¤t_thread_registers); |
---|
| 1206 | } |
---|
| 1207 | |
---|
| 1208 | /* Read new registers if necessary */ |
---|
| 1209 | if (tmp != thread) { |
---|
| 1210 | ret = rtems_gdb_stub_get_thread_regs( |
---|
| 1211 | tmp, (unsigned int *) ¤t_thread_registers); |
---|
| 1212 | |
---|
| 1213 | if (!ret) { |
---|
| 1214 | /* Thread does not exist */ |
---|
| 1215 | strcpy(remcomOutBuffer, "E02"); |
---|
| 1216 | break; |
---|
| 1217 | } |
---|
| 1218 | } |
---|
[6128a4a] | 1219 | |
---|
[a8d953f] | 1220 | current_thread = tmp; |
---|
| 1221 | strcpy(remcomOutBuffer, "OK"); |
---|
| 1222 | } |
---|
| 1223 | #endif |
---|
| 1224 | break; |
---|
| 1225 | |
---|
| 1226 | /* kill the program */ |
---|
| 1227 | case 'k' : /* do nothing */ |
---|
| 1228 | break; |
---|
[6128a4a] | 1229 | } /* switch */ |
---|
| 1230 | |
---|
[a8d953f] | 1231 | /* reply to the request */ |
---|
[6128a4a] | 1232 | putpacket(remcomOutBuffer); |
---|
[a8d953f] | 1233 | } |
---|
| 1234 | } |
---|
| 1235 | |
---|
| 1236 | void |
---|
| 1237 | initializeRemcomErrorFrame() |
---|
| 1238 | { |
---|
| 1239 | lastFrame = ((Frame *) &gdbFrameStack[FRAMESIZE-1]) - 1; |
---|
| 1240 | lastFrame->previous = lastFrame; |
---|
| 1241 | } |
---|
| 1242 | |
---|
[6128a4a] | 1243 | /* this function is used to set up exception handlers for tracing and |
---|
[a8d953f] | 1244 | breakpoints */ |
---|
| 1245 | void set_debug_traps() |
---|
| 1246 | { |
---|
| 1247 | extern void _debug_level7(); |
---|
| 1248 | extern void remcomHandler(); |
---|
| 1249 | int exception; |
---|
| 1250 | |
---|
| 1251 | initializeRemcomErrorFrame(); |
---|
| 1252 | stackPtr = &remcomStack[STACKSIZE/sizeof(int) - 1]; |
---|
| 1253 | |
---|
| 1254 | for (exception = 2; exception <= 23; exception++) |
---|
[6128a4a] | 1255 | m68k_exceptionHandler(exception,_catchException); |
---|
[a8d953f] | 1256 | |
---|
| 1257 | /* level 7 interrupt */ |
---|
[6128a4a] | 1258 | m68k_exceptionHandler(31,_debug_level7); |
---|
| 1259 | |
---|
[a8d953f] | 1260 | /* GDB breakpoint exception (trap #1) */ |
---|
| 1261 | m68k_exceptionHandler(33,_catchException); |
---|
| 1262 | |
---|
| 1263 | /* coded breakpoint exception (trap #2) */ |
---|
| 1264 | m68k_exceptionHandler(34,_catchException); |
---|
[6128a4a] | 1265 | |
---|
[a8d953f] | 1266 | /* This is a trap #8 instruction. Apparently it is someone's software |
---|
| 1267 | convention for some sort of SIGFPE condition. Whose? How many |
---|
| 1268 | people are being screwed by having this code the way it is? |
---|
| 1269 | Is there a clean solution? */ |
---|
| 1270 | m68k_exceptionHandler(40,_catchException); |
---|
[6128a4a] | 1271 | |
---|
[a8d953f] | 1272 | /* 48 to 54 are floating point coprocessor errors */ |
---|
| 1273 | for (exception = 48; exception <= 54; exception++) |
---|
[6128a4a] | 1274 | m68k_exceptionHandler(exception,_catchException); |
---|
[a8d953f] | 1275 | |
---|
| 1276 | if (oldExceptionHook != remcomHandler) |
---|
| 1277 | { |
---|
| 1278 | oldExceptionHook = exceptionHook; |
---|
| 1279 | exceptionHook = remcomHandler; |
---|
| 1280 | } |
---|
[6128a4a] | 1281 | |
---|
[39d08d55] | 1282 | initialized = true; |
---|
[a8d953f] | 1283 | |
---|
| 1284 | } |
---|
| 1285 | |
---|
| 1286 | /* This function will generate a breakpoint exception. It is used at the |
---|
| 1287 | beginning of a program to sync up with a debugger and can be used |
---|
| 1288 | otherwise as a quick means to stop program execution and "break" into |
---|
| 1289 | the debugger. */ |
---|
[6128a4a] | 1290 | |
---|
[a8d953f] | 1291 | void breakpoint() |
---|
| 1292 | { |
---|
| 1293 | if (initialized) BREAKPOINT(); |
---|
| 1294 | } |
---|