1 /*
2 * BedBug Functions
3 */
4
5 #include <common.h>
6 #include <cli.h>
7 #include <command.h>
8 #include <console.h>
9 #include <asm/global_data.h>
10 #include <asm/ptrace.h>
11 #include <linux/ctype.h>
12 #include <net.h>
13 #include <bedbug/type.h>
14 #include <bedbug/bedbug.h>
15 #include <bedbug/regs.h>
16 #include <bedbug/ppc.h>
17
18 DECLARE_GLOBAL_DATA_PTR;
19
20 extern void show_regs __P ((struct pt_regs *));
21 extern int run_command __P ((const char *, int));
22
23 ulong dis_last_addr = 0; /* Last address disassembled */
24 ulong dis_last_len = 20; /* Default disassembler length */
25 CPU_DEBUG_CTX bug_ctx; /* Bedbug context structure */
26
27
28 /* ======================================================================
29 * U-Boot's puts function does not append a newline, so the bedbug stuff
30 * will use this for the output of the dis/assembler.
31 * ====================================================================== */
32
bedbug_puts(const char * str)33 int bedbug_puts (const char *str)
34 {
35 /* -------------------------------------------------- */
36
37 printf ("%s\r\n", str);
38 return 0;
39 } /* bedbug_puts */
40
41
42 /* ======================================================================
43 * Initialize the bug_ctx structure used by the bedbug debugger. This is
44 * specific to the CPU since each has different debug registers and
45 * settings.
46 * ====================================================================== */
47
bedbug_init(void)48 int bedbug_init(void)
49 {
50 /* -------------------------------------------------- */
51 return 0;
52 } /* bedbug_init */
53
54
55 /* ======================================================================
56 * Entry point from the interpreter to the disassembler. Repeated calls
57 * will resume from the last disassembled address.
58 * ====================================================================== */
do_bedbug_dis(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])59 int do_bedbug_dis(struct cmd_tbl *cmdtp, int flag, int argc,
60 char *const argv[])
61 {
62 ulong addr; /* Address to start disassembly from */
63 ulong len; /* # of instructions to disassemble */
64
65 /* -------------------------------------------------- */
66
67 /* Setup to go from the last address if none is given */
68 addr = dis_last_addr;
69 len = dis_last_len;
70
71 if (argc < 2)
72 return CMD_RET_USAGE;
73
74 if ((flag & CMD_FLAG_REPEAT) == 0) {
75 /* New command */
76 addr = hextoul(argv[1], NULL);
77
78 /* If an extra param is given then it is the length */
79 if (argc > 2)
80 len = hextoul(argv[2], NULL);
81 }
82
83 /* Run the disassembler */
84 disppc ((unsigned char *) addr, 0, len, bedbug_puts, F_RADHEX);
85
86 dis_last_addr = addr + (len * 4);
87 dis_last_len = len;
88 return 0;
89 } /* do_bedbug_dis */
90
91 U_BOOT_CMD (ds, 3, 1, do_bedbug_dis,
92 "disassemble memory",
93 "ds <address> [# instructions]");
94
95 /* ======================================================================
96 * Entry point from the interpreter to the assembler. Assembles
97 * instructions in consecutive memory locations until a '.' (period) is
98 * entered on a line by itself.
99 * ====================================================================== */
do_bedbug_asm(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])100 int do_bedbug_asm(struct cmd_tbl *cmdtp, int flag, int argc,
101 char *const argv[])
102 {
103 long mem_addr; /* Address to assemble into */
104 unsigned long instr; /* Machine code for text */
105 char prompt[15]; /* Prompt string for user input */
106 int asm_err; /* Error code from the assembler */
107
108 /* -------------------------------------------------- */
109 int rcode = 0;
110
111 if (argc < 2)
112 return CMD_RET_USAGE;
113
114 printf ("\nEnter '.' when done\n");
115 mem_addr = hextoul(argv[1], NULL);
116
117 while (1) {
118 putc ('\n');
119 disppc ((unsigned char *) mem_addr, 0, 1, bedbug_puts,
120 F_RADHEX);
121
122 sprintf (prompt, "%08lx: ", mem_addr);
123 cli_readline(prompt);
124
125 if (console_buffer[0] && strcmp (console_buffer, ".")) {
126 if ((instr =
127 asmppc (mem_addr, console_buffer,
128 &asm_err)) != 0) {
129 *(unsigned long *) mem_addr = instr;
130 mem_addr += 4;
131 } else {
132 printf ("*** Error: %s ***\n",
133 asm_error_str (asm_err));
134 rcode = 1;
135 }
136 } else {
137 break;
138 }
139 }
140 return rcode;
141 } /* do_bedbug_asm */
142
143 U_BOOT_CMD (as, 2, 0, do_bedbug_asm,
144 "assemble memory", "as <address>");
145
146 /* ======================================================================
147 * Used to set a break point from the interpreter. Simply calls into the
148 * CPU-specific break point set routine.
149 * ====================================================================== */
150
do_bedbug_break(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])151 int do_bedbug_break(struct cmd_tbl *cmdtp, int flag, int argc,
152 char *const argv[])
153 {
154 /* -------------------------------------------------- */
155 if (bug_ctx.do_break)
156 (*bug_ctx.do_break) (cmdtp, flag, argc, argv);
157 return 0;
158
159 } /* do_bedbug_break */
160
161 U_BOOT_CMD (break, 3, 0, do_bedbug_break,
162 "set or clear a breakpoint",
163 " - Set or clear a breakpoint\n"
164 "break <address> - Break at an address\n"
165 "break off <bp#> - Disable breakpoint.\n"
166 "break show - List breakpoints.");
167
168 /* ======================================================================
169 * Called from the debug interrupt routine. Simply calls the CPU-specific
170 * breakpoint handling routine.
171 * ====================================================================== */
172
do_bedbug_breakpoint(struct pt_regs * regs)173 void do_bedbug_breakpoint (struct pt_regs *regs)
174 {
175 /* -------------------------------------------------- */
176
177 if (bug_ctx.break_isr)
178 (*bug_ctx.break_isr) (regs);
179
180 return;
181 } /* do_bedbug_breakpoint */
182
183
184 /* ======================================================================
185 * Called from the CPU-specific breakpoint handling routine. Enter a
186 * mini main loop until the stopped flag is cleared from the breakpoint
187 * context.
188 *
189 * This handles the parts of the debugger that are common to all CPU's.
190 * ====================================================================== */
191
bedbug_main_loop(unsigned long addr,struct pt_regs * regs)192 void bedbug_main_loop (unsigned long addr, struct pt_regs *regs)
193 {
194 int len; /* Length of command line */
195 int flag; /* Command flags */
196 int rc = 0; /* Result from run_command */
197 char prompt_str[20]; /* Prompt string */
198 static char lastcommand[CONFIG_SYS_CBSIZE] = { 0 }; /* previous command */
199 /* -------------------------------------------------- */
200
201 if (bug_ctx.clear)
202 (*bug_ctx.clear) (bug_ctx.current_bp);
203
204 printf ("Breakpoint %d: ", bug_ctx.current_bp);
205 disppc ((unsigned char *) addr, 0, 1, bedbug_puts, F_RADHEX);
206
207 bug_ctx.stopped = 1;
208 bug_ctx.regs = regs;
209
210 sprintf (prompt_str, "BEDBUG.%d =>", bug_ctx.current_bp);
211
212 /* A miniature main loop */
213 while (bug_ctx.stopped) {
214 len = cli_readline(prompt_str);
215
216 flag = 0; /* assume no special flags for now */
217
218 if (len > 0)
219 strcpy (lastcommand, console_buffer);
220 else if (len == 0)
221 flag |= CMD_FLAG_REPEAT;
222
223 if (len == -1)
224 printf ("<INTERRUPT>\n");
225 else
226 rc = run_command_repeatable(lastcommand, flag);
227
228 if (rc <= 0) {
229 /* invalid command or not repeatable, forget it */
230 lastcommand[0] = 0;
231 }
232 }
233
234 bug_ctx.regs = NULL;
235 bug_ctx.current_bp = 0;
236
237 return;
238 } /* bedbug_main_loop */
239
240
241 /* ======================================================================
242 * Interpreter command to continue from a breakpoint. Just clears the
243 * stopped flag in the context so that the breakpoint routine will
244 * return.
245 * ====================================================================== */
do_bedbug_continue(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])246 int do_bedbug_continue(struct cmd_tbl *cmdtp, int flag, int argc,
247 char *const argv[])
248 {
249 /* -------------------------------------------------- */
250
251 if (!bug_ctx.stopped) {
252 printf ("Not at a breakpoint\n");
253 return 1;
254 }
255
256 bug_ctx.stopped = 0;
257 return 0;
258 } /* do_bedbug_continue */
259
260 U_BOOT_CMD (continue, 1, 0, do_bedbug_continue,
261 "continue from a breakpoint",
262 "");
263
264 /* ======================================================================
265 * Interpreter command to continue to the next instruction, stepping into
266 * subroutines. Works by calling the find_next_addr() routine to compute
267 * the address passes control to the CPU-specific set breakpoint routine
268 * for the current breakpoint number.
269 * ====================================================================== */
do_bedbug_step(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])270 int do_bedbug_step(struct cmd_tbl *cmdtp, int flag, int argc,
271 char *const argv[])
272 {
273 unsigned long addr; /* Address to stop at */
274
275 /* -------------------------------------------------- */
276
277 if (!bug_ctx.stopped) {
278 printf ("Not at a breakpoint\n");
279 return 1;
280 }
281
282 if (!find_next_address((unsigned char *) &addr, false, bug_ctx.regs))
283 return 1;
284
285 if (bug_ctx.set)
286 (*bug_ctx.set) (bug_ctx.current_bp, addr);
287
288 bug_ctx.stopped = 0;
289 return 0;
290 } /* do_bedbug_step */
291
292 U_BOOT_CMD (step, 1, 1, do_bedbug_step,
293 "single step execution.",
294 "");
295
296 /* ======================================================================
297 * Interpreter command to continue to the next instruction, stepping over
298 * subroutines. Works by calling the find_next_addr() routine to compute
299 * the address passes control to the CPU-specific set breakpoint routine
300 * for the current breakpoint number.
301 * ====================================================================== */
do_bedbug_next(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])302 int do_bedbug_next(struct cmd_tbl *cmdtp, int flag, int argc,
303 char *const argv[])
304 {
305 unsigned long addr; /* Address to stop at */
306
307 /* -------------------------------------------------- */
308
309 if (!bug_ctx.stopped) {
310 printf ("Not at a breakpoint\n");
311 return 1;
312 }
313
314 if (!find_next_address((unsigned char *) &addr, true, bug_ctx.regs))
315 return 1;
316
317 if (bug_ctx.set)
318 (*bug_ctx.set) (bug_ctx.current_bp, addr);
319
320 bug_ctx.stopped = 0;
321 return 0;
322 } /* do_bedbug_next */
323
324 U_BOOT_CMD (next, 1, 1, do_bedbug_next,
325 "single step execution, stepping over subroutines.",
326 "");
327
328 /* ======================================================================
329 * Interpreter command to print the current stack. This assumes an EABI
330 * architecture, so it starts with GPR R1 and works back up the stack.
331 * ====================================================================== */
do_bedbug_stack(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])332 int do_bedbug_stack(struct cmd_tbl *cmdtp, int flag, int argc,
333 char *const argv[])
334 {
335 unsigned long sp; /* Stack pointer */
336 unsigned long func; /* LR from stack */
337 int depth; /* Stack iteration level */
338 int skip = 1; /* Flag to skip the first entry */
339 unsigned long top; /* Top of memory address */
340
341 /* -------------------------------------------------- */
342
343 if (!bug_ctx.stopped) {
344 printf ("Not at a breakpoint\n");
345 return 1;
346 }
347
348 top = gd->ram_start + gd->ram_size;
349 depth = 0;
350
351 printf ("Depth PC\n");
352 printf ("----- --------\n");
353 printf ("%5d %08lx\n", depth++, bug_ctx.regs->nip);
354
355 sp = bug_ctx.regs->gpr[1];
356 func = *(unsigned long *) (sp + 4);
357
358 while ((func < top) && (sp < top)) {
359 if (!skip)
360 printf ("%5d %08lx\n", depth++, func);
361 else
362 --skip;
363
364 sp = *(unsigned long *) sp;
365 func = *(unsigned long *) (sp + 4);
366 }
367 return 0;
368 } /* do_bedbug_stack */
369
370 U_BOOT_CMD (where, 1, 1, do_bedbug_stack,
371 "Print the running stack.",
372 "");
373
374 /* ======================================================================
375 * Interpreter command to dump the registers. Calls the CPU-specific
376 * show registers routine.
377 * ====================================================================== */
do_bedbug_rdump(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])378 int do_bedbug_rdump(struct cmd_tbl *cmdtp, int flag, int argc,
379 char *const argv[])
380 {
381 /* -------------------------------------------------- */
382
383 if (!bug_ctx.stopped) {
384 printf ("Not at a breakpoint\n");
385 return 1;
386 }
387
388 show_regs (bug_ctx.regs);
389 return 0;
390 } /* do_bedbug_rdump */
391
392 U_BOOT_CMD (rdump, 1, 1, do_bedbug_rdump,
393 "Show registers.", "");
394 /* ====================================================================== */
395
396
397 /*
398 * Copyright (c) 2001 William L. Pitts
399 * All rights reserved.
400 *
401 * Redistribution and use in source and binary forms are freely
402 * permitted provided that the above copyright notice and this
403 * paragraph and the following disclaimer are duplicated in all
404 * such forms.
405 *
406 * This software is provided "AS IS" and without any express or
407 * implied warranties, including, without limitation, the implied
408 * warranties of merchantability and fitness for a particular
409 * purpose.
410 */
411