blob: eabc583d216d5572f4c8fa0ded185d4236a4df99 [file] [log] [blame]
wdenk1dda0b12002-08-27 10:52:29 +00001/*
2 * Bedbug Functions specific to the PPC405 chip
3 */
4
5#include <common.h>
6#include <command.h>
7#include <linux/ctype.h>
8
9#include <cmd_bedbug.h>
10#include <bedbug/bedbug.h>
11#include <bedbug/regs.h>
12#include <bedbug/ppc.h>
13
14#if (CONFIG_COMMANDS & CFG_CMD_BEDBUG) && defined(CONFIG_4xx)
15
16#define MAX_BREAK_POINTS 4
17
18extern CPU_DEBUG_CTX bug_ctx;
19
20void bedbug405_init __P ((void));
21void bedbug405_do_break __P ((cmd_tbl_t *, int, int, char *[]));
22void bedbug405_break_isr __P ((struct pt_regs *));
23int bedbug405_find_empty __P ((void));
24int bedbug405_set __P ((int, unsigned long));
25int bedbug405_clear __P ((int));
26
27
28/* ======================================================================
29 * Initialize the global bug_ctx structure for the IBM PPC405. Clear all
30 * of the breakpoints.
31 * ====================================================================== */
32
33void bedbug405_init (void)
34{
35 int i;
36
37 /* -------------------------------------------------- */
38
39 bug_ctx.hw_debug_enabled = 0;
40 bug_ctx.stopped = 0;
41 bug_ctx.current_bp = 0;
42 bug_ctx.regs = NULL;
43
44 bug_ctx.do_break = bedbug405_do_break;
45 bug_ctx.break_isr = bedbug405_break_isr;
46 bug_ctx.find_empty = bedbug405_find_empty;
47 bug_ctx.set = bedbug405_set;
48 bug_ctx.clear = bedbug405_clear;
49
50 for (i = 1; i <= MAX_BREAK_POINTS; ++i)
51 (*bug_ctx.clear) (i);
52
53 puts ("BEDBUG:ready\n");
54 return;
55} /* bedbug_init_breakpoints */
56
57
58
59/* ======================================================================
60 * Set/clear/show one of the hardware breakpoints for the 405. The "off"
61 * string will disable a specific breakpoint. The "show" string will
62 * display the current breakpoints. Otherwise an address will set a
63 * breakpoint at that address. Setting a breakpoint uses the CPU-specific
64 * set routine which will assign a breakpoint number.
65 * ====================================================================== */
66
67void bedbug405_do_break (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
68{
69 long addr = 0; /* Address to break at */
70 int which_bp; /* Breakpoint number */
71
72 /* -------------------------------------------------- */
73
74 if (argc < 2) {
75 printf ("Usage:\n%s\n", cmdtp->usage);
76 return;
77 }
78
79 /* Turn off a breakpoint */
80
81 if (strcmp (argv[1], "off") == 0) {
82 if (bug_ctx.hw_debug_enabled == 0) {
83 printf ("No breakpoints enabled\n");
84 return;
85 }
86
87 which_bp = simple_strtoul (argv[2], NULL, 10);
88
89 if (bug_ctx.clear)
90 (*bug_ctx.clear) (which_bp);
91
92 printf ("Breakpoint %d removed\n", which_bp);
93 return;
94 }
95
96 /* Show a list of breakpoints */
97
98 if (strcmp (argv[1], "show") == 0) {
99 for (which_bp = 1; which_bp <= MAX_BREAK_POINTS; ++which_bp) {
100
101 switch (which_bp) {
102 case 1:
103 addr = GET_IAC1 ();
104 break;
105 case 2:
106 addr = GET_IAC2 ();
107 break;
108 case 3:
109 addr = GET_IAC3 ();
110 break;
111 case 4:
112 addr = GET_IAC4 ();
113 break;
114 }
115
116 printf ("Breakpoint [%d]: ", which_bp);
117 if (addr == 0)
118 printf ("NOT SET\n");
119 else
120 disppc ((unsigned char *) addr, 0, 1, bedbug_puts,
121 F_RADHEX);
122 }
123 return;
124 }
125
126 /* Set a breakpoint at the address */
127
128 if (!isdigit (argv[1][0])) {
129 printf ("Usage:\n%s\n", cmdtp->usage);
130 return;
131 }
132
133 addr = simple_strtoul (argv[1], NULL, 16) & 0xfffffffc;
134
135 if ((bug_ctx.set) && (which_bp = (*bug_ctx.set) (0, addr)) > 0) {
136 printf ("Breakpoint [%d]: ", which_bp);
137 disppc ((unsigned char *) addr, 0, 1, bedbug_puts, F_RADHEX);
138 }
139
140 return;
141} /* bedbug405_do_break */
142
143
144
145/* ======================================================================
146 * Handle a breakpoint. First determine which breakpoint was hit by
147 * looking at the DeBug Status Register (DBSR), clear the breakpoint
148 * and enter a mini main loop. Stay in the loop until the stopped flag
149 * in the debug context is cleared.
150 * ====================================================================== */
151
152void bedbug405_break_isr (struct pt_regs *regs)
153{
154 unsigned long dbsr_val; /* Value of the DBSR */
155 unsigned long addr = 0; /* Address stopped at */
156
157 /* -------------------------------------------------- */
158
159 dbsr_val = GET_DBSR ();
160
161 if (dbsr_val & DBSR_IA1) {
162 bug_ctx.current_bp = 1;
163 addr = GET_IAC1 ();
164 SET_DBSR (DBSR_IA1); /* Write a 1 to clear */
165 } else if (dbsr_val & DBSR_IA2) {
166 bug_ctx.current_bp = 2;
167 addr = GET_IAC2 ();
168 SET_DBSR (DBSR_IA2); /* Write a 1 to clear */
169 } else if (dbsr_val & DBSR_IA3) {
170 bug_ctx.current_bp = 3;
171 addr = GET_IAC3 ();
172 SET_DBSR (DBSR_IA3); /* Write a 1 to clear */
173 } else if (dbsr_val & DBSR_IA4) {
174 bug_ctx.current_bp = 4;
175 addr = GET_IAC4 ();
176 SET_DBSR (DBSR_IA4); /* Write a 1 to clear */
177 }
178
179 bedbug_main_loop (addr, regs);
180 return;
181} /* bedbug405_break_isr */
182
183
184
185/* ======================================================================
186 * Look through all of the hardware breakpoints available to see if one
187 * is unused.
188 * ====================================================================== */
189
190int bedbug405_find_empty (void)
191{
192 /* -------------------------------------------------- */
193
194 if (GET_IAC1 () == 0)
195 return 1;
196
197 if (GET_IAC2 () == 0)
198 return 2;
199
200 if (GET_IAC3 () == 0)
201 return 3;
202
203 if (GET_IAC4 () == 0)
204 return 4;
205
206 return 0;
207} /* bedbug405_find_empty */
208
209
210
211/* ======================================================================
212 * Set a breakpoint. If 'which_bp' is zero then find an unused breakpoint
213 * number, otherwise reassign the given breakpoint. If hardware debugging
214 * is not enabled, then turn it on via the MSR and DBCR0. Set the break
215 * address in the appropriate IACx register and enable proper address
216 * beakpoint in DBCR0.
217 * ====================================================================== */
218
219int bedbug405_set (int which_bp, unsigned long addr)
220{
221 /* -------------------------------------------------- */
222
223 /* Only look if which_bp == 0, else use which_bp */
224 if ((bug_ctx.find_empty) && (!which_bp) &&
225 (which_bp = (*bug_ctx.find_empty) ()) == 0) {
226 printf ("All breakpoints in use\n");
227 return 0;
228 }
229
230 if (which_bp < 1 || which_bp > MAX_BREAK_POINTS) {
231 printf ("Invalid break point # %d\n", which_bp);
232 return 0;
233 }
234
235 if (!bug_ctx.hw_debug_enabled) {
236 SET_MSR (GET_MSR () | 0x200); /* set MSR[ DE ] */
237 SET_DBCR0 (GET_DBCR0 () | DBCR0_IDM);
238 bug_ctx.hw_debug_enabled = 1;
239 }
240
241 switch (which_bp) {
242 case 1:
243 SET_IAC1 (addr);
244 SET_DBCR0 (GET_DBCR0 () | DBCR0_IA1);
245 break;
246
247 case 2:
248 SET_IAC2 (addr);
249 SET_DBCR0 (GET_DBCR0 () | DBCR0_IA2);
250 break;
251
252 case 3:
253 SET_IAC3 (addr);
254 SET_DBCR0 (GET_DBCR0 () | DBCR0_IA3);
255 break;
256
257 case 4:
258 SET_IAC4 (addr);
259 SET_DBCR0 (GET_DBCR0 () | DBCR0_IA4);
260 break;
261 }
262
263 return which_bp;
264} /* bedbug405_set */
265
266
267
268/* ======================================================================
269 * Disable a specific breakoint by setting the appropriate IACx register
270 * to zero and claring the instruction address breakpoint in DBCR0.
271 * ====================================================================== */
272
273int bedbug405_clear (int which_bp)
274{
275 /* -------------------------------------------------- */
276
277 if (which_bp < 1 || which_bp > MAX_BREAK_POINTS) {
278 printf ("Invalid break point # (%d)\n", which_bp);
279 return -1;
280 }
281
282 switch (which_bp) {
283 case 1:
284 SET_IAC1 (0);
285 SET_DBCR0 (GET_DBCR0 () & ~DBCR0_IA1);
286 break;
287
288 case 2:
289 SET_IAC2 (0);
290 SET_DBCR0 (GET_DBCR0 () & ~DBCR0_IA2);
291 break;
292
293 case 3:
294 SET_IAC3 (0);
295 SET_DBCR0 (GET_DBCR0 () & ~DBCR0_IA3);
296 break;
297
298 case 4:
299 SET_IAC4 (0);
300 SET_DBCR0 (GET_DBCR0 () & ~DBCR0_IA4);
301 break;
302 }
303
304 return 0;
305} /* bedbug405_clear */
306
307
308/* ====================================================================== */
309#endif