xref: /openbmc/linux/drivers/misc/kgdbts.c (revision 1fa6ac37)
1 /*
2  * kgdbts is a test suite for kgdb for the sole purpose of validating
3  * that key pieces of the kgdb internals are working properly such as
4  * HW/SW breakpoints, single stepping, and NMI.
5  *
6  * Created by: Jason Wessel <jason.wessel@windriver.com>
7  *
8  * Copyright (c) 2008 Wind River Systems, Inc.
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
17  * See the GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22  */
23 /* Information about the kgdb test suite.
24  * -------------------------------------
25  *
26  * The kgdb test suite is designed as a KGDB I/O module which
27  * simulates the communications that a debugger would have with kgdb.
28  * The tests are broken up in to a line by line and referenced here as
29  * a "get" which is kgdb requesting input and "put" which is kgdb
30  * sending a response.
31  *
32  * The kgdb suite can be invoked from the kernel command line
33  * arguments system or executed dynamically at run time.  The test
34  * suite uses the variable "kgdbts" to obtain the information about
35  * which tests to run and to configure the verbosity level.  The
36  * following are the various characters you can use with the kgdbts=
37  * line:
38  *
39  * When using the "kgdbts=" you only choose one of the following core
40  * test types:
41  * A = Run all the core tests silently
42  * V1 = Run all the core tests with minimal output
43  * V2 = Run all the core tests in debug mode
44  *
45  * You can also specify optional tests:
46  * N## = Go to sleep with interrupts of for ## seconds
47  *       to test the HW NMI watchdog
48  * F## = Break at do_fork for ## iterations
49  * S## = Break at sys_open for ## iterations
50  * I## = Run the single step test ## iterations
51  *
52  * NOTE: that the do_fork and sys_open tests are mutually exclusive.
53  *
54  * To invoke the kgdb test suite from boot you use a kernel start
55  * argument as follows:
56  * 	kgdbts=V1 kgdbwait
57  * Or if you wanted to perform the NMI test for 6 seconds and do_fork
58  * test for 100 forks, you could use:
59  * 	kgdbts=V1N6F100 kgdbwait
60  *
61  * The test suite can also be invoked at run time with:
62  *	echo kgdbts=V1N6F100 > /sys/module/kgdbts/parameters/kgdbts
63  * Or as another example:
64  *	echo kgdbts=V2 > /sys/module/kgdbts/parameters/kgdbts
65  *
66  * When developing a new kgdb arch specific implementation or
67  * using these tests for the purpose of regression testing,
68  * several invocations are required.
69  *
70  * 1) Boot with the test suite enabled by using the kernel arguments
71  *       "kgdbts=V1F100 kgdbwait"
72  *    ## If kgdb arch specific implementation has NMI use
73  *       "kgdbts=V1N6F100
74  *
75  * 2) After the system boot run the basic test.
76  * echo kgdbts=V1 > /sys/module/kgdbts/parameters/kgdbts
77  *
78  * 3) Run the concurrency tests.  It is best to use n+1
79  *    while loops where n is the number of cpus you have
80  *    in your system.  The example below uses only two
81  *    loops.
82  *
83  * ## This tests break points on sys_open
84  * while [ 1 ] ; do find / > /dev/null 2>&1 ; done &
85  * while [ 1 ] ; do find / > /dev/null 2>&1 ; done &
86  * echo kgdbts=V1S10000 > /sys/module/kgdbts/parameters/kgdbts
87  * fg # and hit control-c
88  * fg # and hit control-c
89  * ## This tests break points on do_fork
90  * while [ 1 ] ; do date > /dev/null ; done &
91  * while [ 1 ] ; do date > /dev/null ; done &
92  * echo kgdbts=V1F1000 > /sys/module/kgdbts/parameters/kgdbts
93  * fg # and hit control-c
94  *
95  */
96 
97 #include <linux/kernel.h>
98 #include <linux/kgdb.h>
99 #include <linux/ctype.h>
100 #include <linux/uaccess.h>
101 #include <linux/syscalls.h>
102 #include <linux/nmi.h>
103 #include <linux/delay.h>
104 #include <linux/kthread.h>
105 
106 #define v1printk(a...) do { \
107 	if (verbose) \
108 		printk(KERN_INFO a); \
109 	} while (0)
110 #define v2printk(a...) do { \
111 	if (verbose > 1) \
112 		printk(KERN_INFO a); \
113 		touch_nmi_watchdog();	\
114 	} while (0)
115 #define eprintk(a...) do { \
116 		printk(KERN_ERR a); \
117 		WARN_ON(1); \
118 	} while (0)
119 #define MAX_CONFIG_LEN		40
120 
121 static struct kgdb_io kgdbts_io_ops;
122 static char get_buf[BUFMAX];
123 static int get_buf_cnt;
124 static char put_buf[BUFMAX];
125 static int put_buf_cnt;
126 static char scratch_buf[BUFMAX];
127 static int verbose;
128 static int repeat_test;
129 static int test_complete;
130 static int send_ack;
131 static int final_ack;
132 static int force_hwbrks;
133 static int hwbreaks_ok;
134 static int hw_break_val;
135 static int hw_break_val2;
136 #if defined(CONFIG_ARM) || defined(CONFIG_MIPS) || defined(CONFIG_SPARC)
137 static int arch_needs_sstep_emulation = 1;
138 #else
139 static int arch_needs_sstep_emulation;
140 #endif
141 static unsigned long sstep_addr;
142 static int sstep_state;
143 
144 /* Storage for the registers, in GDB format. */
145 static unsigned long kgdbts_gdb_regs[(NUMREGBYTES +
146 					sizeof(unsigned long) - 1) /
147 					sizeof(unsigned long)];
148 static struct pt_regs kgdbts_regs;
149 
150 /* -1 = init not run yet, 0 = unconfigured, 1 = configured. */
151 static int configured		= -1;
152 
153 #ifdef CONFIG_KGDB_TESTS_BOOT_STRING
154 static char config[MAX_CONFIG_LEN] = CONFIG_KGDB_TESTS_BOOT_STRING;
155 #else
156 static char config[MAX_CONFIG_LEN];
157 #endif
158 static struct kparam_string kps = {
159 	.string			= config,
160 	.maxlen			= MAX_CONFIG_LEN,
161 };
162 
163 static void fill_get_buf(char *buf);
164 
165 struct test_struct {
166 	char *get;
167 	char *put;
168 	void (*get_handler)(char *);
169 	int (*put_handler)(char *, char *);
170 };
171 
172 struct test_state {
173 	char *name;
174 	struct test_struct *tst;
175 	int idx;
176 	int (*run_test) (int, int);
177 	int (*validate_put) (char *);
178 };
179 
180 static struct test_state ts;
181 
182 static int kgdbts_unreg_thread(void *ptr)
183 {
184 	/* Wait until the tests are complete and then ungresiter the I/O
185 	 * driver.
186 	 */
187 	while (!final_ack)
188 		msleep_interruptible(1500);
189 
190 	if (configured)
191 		kgdb_unregister_io_module(&kgdbts_io_ops);
192 	configured = 0;
193 
194 	return 0;
195 }
196 
197 /* This is noinline such that it can be used for a single location to
198  * place a breakpoint
199  */
200 static noinline void kgdbts_break_test(void)
201 {
202 	v2printk("kgdbts: breakpoint complete\n");
203 }
204 
205 /* Lookup symbol info in the kernel */
206 static unsigned long lookup_addr(char *arg)
207 {
208 	unsigned long addr = 0;
209 
210 	if (!strcmp(arg, "kgdbts_break_test"))
211 		addr = (unsigned long)kgdbts_break_test;
212 	else if (!strcmp(arg, "sys_open"))
213 		addr = (unsigned long)sys_open;
214 	else if (!strcmp(arg, "do_fork"))
215 		addr = (unsigned long)do_fork;
216 	else if (!strcmp(arg, "hw_break_val"))
217 		addr = (unsigned long)&hw_break_val;
218 	return addr;
219 }
220 
221 static void break_helper(char *bp_type, char *arg, unsigned long vaddr)
222 {
223 	unsigned long addr;
224 
225 	if (arg)
226 		addr = lookup_addr(arg);
227 	else
228 		addr = vaddr;
229 
230 	sprintf(scratch_buf, "%s,%lx,%i", bp_type, addr,
231 		BREAK_INSTR_SIZE);
232 	fill_get_buf(scratch_buf);
233 }
234 
235 static void sw_break(char *arg)
236 {
237 	break_helper(force_hwbrks ? "Z1" : "Z0", arg, 0);
238 }
239 
240 static void sw_rem_break(char *arg)
241 {
242 	break_helper(force_hwbrks ? "z1" : "z0", arg, 0);
243 }
244 
245 static void hw_break(char *arg)
246 {
247 	break_helper("Z1", arg, 0);
248 }
249 
250 static void hw_rem_break(char *arg)
251 {
252 	break_helper("z1", arg, 0);
253 }
254 
255 static void hw_write_break(char *arg)
256 {
257 	break_helper("Z2", arg, 0);
258 }
259 
260 static void hw_rem_write_break(char *arg)
261 {
262 	break_helper("z2", arg, 0);
263 }
264 
265 static void hw_access_break(char *arg)
266 {
267 	break_helper("Z4", arg, 0);
268 }
269 
270 static void hw_rem_access_break(char *arg)
271 {
272 	break_helper("z4", arg, 0);
273 }
274 
275 static void hw_break_val_access(void)
276 {
277 	hw_break_val2 = hw_break_val;
278 }
279 
280 static void hw_break_val_write(void)
281 {
282 	hw_break_val++;
283 }
284 
285 static int check_and_rewind_pc(char *put_str, char *arg)
286 {
287 	unsigned long addr = lookup_addr(arg);
288 	int offset = 0;
289 
290 	kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
291 		 NUMREGBYTES);
292 	gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
293 	v2printk("Stopped at IP: %lx\n", instruction_pointer(&kgdbts_regs));
294 #ifdef CONFIG_X86
295 	/* On x86 a breakpoint stop requires it to be decremented */
296 	if (addr + 1 == kgdbts_regs.ip)
297 		offset = -1;
298 #elif defined(CONFIG_SUPERH)
299 	/* On SUPERH a breakpoint stop requires it to be decremented */
300 	if (addr + 2 == kgdbts_regs.pc)
301 		offset = -2;
302 #endif
303 	if (strcmp(arg, "silent") &&
304 		instruction_pointer(&kgdbts_regs) + offset != addr) {
305 		eprintk("kgdbts: BP mismatch %lx expected %lx\n",
306 			   instruction_pointer(&kgdbts_regs) + offset, addr);
307 		return 1;
308 	}
309 #ifdef CONFIG_X86
310 	/* On x86 adjust the instruction pointer if needed */
311 	kgdbts_regs.ip += offset;
312 #elif defined(CONFIG_SUPERH)
313 	kgdbts_regs.pc += offset;
314 #endif
315 	return 0;
316 }
317 
318 static int check_single_step(char *put_str, char *arg)
319 {
320 	unsigned long addr = lookup_addr(arg);
321 	/*
322 	 * From an arch indepent point of view the instruction pointer
323 	 * should be on a different instruction
324 	 */
325 	kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
326 		 NUMREGBYTES);
327 	gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
328 	v2printk("Singlestep stopped at IP: %lx\n",
329 		   instruction_pointer(&kgdbts_regs));
330 	if (instruction_pointer(&kgdbts_regs) == addr) {
331 		eprintk("kgdbts: SingleStep failed at %lx\n",
332 			   instruction_pointer(&kgdbts_regs));
333 		return 1;
334 	}
335 
336 	return 0;
337 }
338 
339 static void write_regs(char *arg)
340 {
341 	memset(scratch_buf, 0, sizeof(scratch_buf));
342 	scratch_buf[0] = 'G';
343 	pt_regs_to_gdb_regs(kgdbts_gdb_regs, &kgdbts_regs);
344 	kgdb_mem2hex((char *)kgdbts_gdb_regs, &scratch_buf[1], NUMREGBYTES);
345 	fill_get_buf(scratch_buf);
346 }
347 
348 static void skip_back_repeat_test(char *arg)
349 {
350 	int go_back = simple_strtol(arg, NULL, 10);
351 
352 	repeat_test--;
353 	if (repeat_test <= 0)
354 		ts.idx++;
355 	else
356 		ts.idx -= go_back;
357 	fill_get_buf(ts.tst[ts.idx].get);
358 }
359 
360 static int got_break(char *put_str, char *arg)
361 {
362 	test_complete = 1;
363 	if (!strncmp(put_str+1, arg, 2)) {
364 		if (!strncmp(arg, "T0", 2))
365 			test_complete = 2;
366 		return 0;
367 	}
368 	return 1;
369 }
370 
371 static void emul_sstep_get(char *arg)
372 {
373 	if (!arch_needs_sstep_emulation) {
374 		fill_get_buf(arg);
375 		return;
376 	}
377 	switch (sstep_state) {
378 	case 0:
379 		v2printk("Emulate single step\n");
380 		/* Start by looking at the current PC */
381 		fill_get_buf("g");
382 		break;
383 	case 1:
384 		/* set breakpoint */
385 		break_helper("Z0", NULL, sstep_addr);
386 		break;
387 	case 2:
388 		/* Continue */
389 		fill_get_buf("c");
390 		break;
391 	case 3:
392 		/* Clear breakpoint */
393 		break_helper("z0", NULL, sstep_addr);
394 		break;
395 	default:
396 		eprintk("kgdbts: ERROR failed sstep get emulation\n");
397 	}
398 	sstep_state++;
399 }
400 
401 static int emul_sstep_put(char *put_str, char *arg)
402 {
403 	if (!arch_needs_sstep_emulation) {
404 		if (!strncmp(put_str+1, arg, 2))
405 			return 0;
406 		return 1;
407 	}
408 	switch (sstep_state) {
409 	case 1:
410 		/* validate the "g" packet to get the IP */
411 		kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
412 			 NUMREGBYTES);
413 		gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
414 		v2printk("Stopped at IP: %lx\n",
415 			 instruction_pointer(&kgdbts_regs));
416 		/* Want to stop at IP + break instruction size by default */
417 		sstep_addr = instruction_pointer(&kgdbts_regs) +
418 			BREAK_INSTR_SIZE;
419 		break;
420 	case 2:
421 		if (strncmp(put_str, "$OK", 3)) {
422 			eprintk("kgdbts: failed sstep break set\n");
423 			return 1;
424 		}
425 		break;
426 	case 3:
427 		if (strncmp(put_str, "$T0", 3)) {
428 			eprintk("kgdbts: failed continue sstep\n");
429 			return 1;
430 		}
431 		break;
432 	case 4:
433 		if (strncmp(put_str, "$OK", 3)) {
434 			eprintk("kgdbts: failed sstep break unset\n");
435 			return 1;
436 		}
437 		/* Single step is complete so continue on! */
438 		sstep_state = 0;
439 		return 0;
440 	default:
441 		eprintk("kgdbts: ERROR failed sstep put emulation\n");
442 	}
443 
444 	/* Continue on the same test line until emulation is complete */
445 	ts.idx--;
446 	return 0;
447 }
448 
449 static int final_ack_set(char *put_str, char *arg)
450 {
451 	if (strncmp(put_str+1, arg, 2))
452 		return 1;
453 	final_ack = 1;
454 	return 0;
455 }
456 /*
457  * Test to plant a breakpoint and detach, which should clear out the
458  * breakpoint and restore the original instruction.
459  */
460 static struct test_struct plant_and_detach_test[] = {
461 	{ "?", "S0*" }, /* Clear break points */
462 	{ "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
463 	{ "D", "OK" }, /* Detach */
464 	{ "", "" },
465 };
466 
467 /*
468  * Simple test to write in a software breakpoint, check for the
469  * correct stop location and detach.
470  */
471 static struct test_struct sw_breakpoint_test[] = {
472 	{ "?", "S0*" }, /* Clear break points */
473 	{ "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
474 	{ "c", "T0*", }, /* Continue */
475 	{ "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
476 	{ "write", "OK", write_regs },
477 	{ "kgdbts_break_test", "OK", sw_rem_break }, /*remove breakpoint */
478 	{ "D", "OK" }, /* Detach */
479 	{ "D", "OK", NULL,  got_break }, /* On success we made it here */
480 	{ "", "" },
481 };
482 
483 /*
484  * Test a known bad memory read location to test the fault handler and
485  * read bytes 1-8 at the bad address
486  */
487 static struct test_struct bad_read_test[] = {
488 	{ "?", "S0*" }, /* Clear break points */
489 	{ "m0,1", "E*" }, /* read 1 byte at address 1 */
490 	{ "m0,2", "E*" }, /* read 1 byte at address 2 */
491 	{ "m0,3", "E*" }, /* read 1 byte at address 3 */
492 	{ "m0,4", "E*" }, /* read 1 byte at address 4 */
493 	{ "m0,5", "E*" }, /* read 1 byte at address 5 */
494 	{ "m0,6", "E*" }, /* read 1 byte at address 6 */
495 	{ "m0,7", "E*" }, /* read 1 byte at address 7 */
496 	{ "m0,8", "E*" }, /* read 1 byte at address 8 */
497 	{ "D", "OK" }, /* Detach which removes all breakpoints and continues */
498 	{ "", "" },
499 };
500 
501 /*
502  * Test for hitting a breakpoint, remove it, single step, plant it
503  * again and detach.
504  */
505 static struct test_struct singlestep_break_test[] = {
506 	{ "?", "S0*" }, /* Clear break points */
507 	{ "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
508 	{ "c", "T0*", }, /* Continue */
509 	{ "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
510 	{ "write", "OK", write_regs }, /* Write registers */
511 	{ "kgdbts_break_test", "OK", sw_rem_break }, /*remove breakpoint */
512 	{ "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
513 	{ "g", "kgdbts_break_test", NULL, check_single_step },
514 	{ "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
515 	{ "c", "T0*", }, /* Continue */
516 	{ "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
517 	{ "write", "OK", write_regs }, /* Write registers */
518 	{ "D", "OK" }, /* Remove all breakpoints and continues */
519 	{ "", "" },
520 };
521 
522 /*
523  * Test for hitting a breakpoint at do_fork for what ever the number
524  * of iterations required by the variable repeat_test.
525  */
526 static struct test_struct do_fork_test[] = {
527 	{ "?", "S0*" }, /* Clear break points */
528 	{ "do_fork", "OK", sw_break, }, /* set sw breakpoint */
529 	{ "c", "T0*", }, /* Continue */
530 	{ "g", "do_fork", NULL, check_and_rewind_pc }, /* check location */
531 	{ "write", "OK", write_regs }, /* Write registers */
532 	{ "do_fork", "OK", sw_rem_break }, /*remove breakpoint */
533 	{ "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
534 	{ "g", "do_fork", NULL, check_single_step },
535 	{ "do_fork", "OK", sw_break, }, /* set sw breakpoint */
536 	{ "7", "T0*", skip_back_repeat_test }, /* Loop based on repeat_test */
537 	{ "D", "OK", NULL, final_ack_set }, /* detach and unregister I/O */
538 	{ "", "" },
539 };
540 
541 /* Test for hitting a breakpoint at sys_open for what ever the number
542  * of iterations required by the variable repeat_test.
543  */
544 static struct test_struct sys_open_test[] = {
545 	{ "?", "S0*" }, /* Clear break points */
546 	{ "sys_open", "OK", sw_break, }, /* set sw breakpoint */
547 	{ "c", "T0*", }, /* Continue */
548 	{ "g", "sys_open", NULL, check_and_rewind_pc }, /* check location */
549 	{ "write", "OK", write_regs }, /* Write registers */
550 	{ "sys_open", "OK", sw_rem_break }, /*remove breakpoint */
551 	{ "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
552 	{ "g", "sys_open", NULL, check_single_step },
553 	{ "sys_open", "OK", sw_break, }, /* set sw breakpoint */
554 	{ "7", "T0*", skip_back_repeat_test }, /* Loop based on repeat_test */
555 	{ "D", "OK", NULL, final_ack_set }, /* detach and unregister I/O */
556 	{ "", "" },
557 };
558 
559 /*
560  * Test for hitting a simple hw breakpoint
561  */
562 static struct test_struct hw_breakpoint_test[] = {
563 	{ "?", "S0*" }, /* Clear break points */
564 	{ "kgdbts_break_test", "OK", hw_break, }, /* set hw breakpoint */
565 	{ "c", "T0*", }, /* Continue */
566 	{ "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
567 	{ "write", "OK", write_regs },
568 	{ "kgdbts_break_test", "OK", hw_rem_break }, /*remove breakpoint */
569 	{ "D", "OK" }, /* Detach */
570 	{ "D", "OK", NULL,  got_break }, /* On success we made it here */
571 	{ "", "" },
572 };
573 
574 /*
575  * Test for hitting a hw write breakpoint
576  */
577 static struct test_struct hw_write_break_test[] = {
578 	{ "?", "S0*" }, /* Clear break points */
579 	{ "hw_break_val", "OK", hw_write_break, }, /* set hw breakpoint */
580 	{ "c", "T0*", NULL, got_break }, /* Continue */
581 	{ "g", "silent", NULL, check_and_rewind_pc },
582 	{ "write", "OK", write_regs },
583 	{ "hw_break_val", "OK", hw_rem_write_break }, /*remove breakpoint */
584 	{ "D", "OK" }, /* Detach */
585 	{ "D", "OK", NULL,  got_break }, /* On success we made it here */
586 	{ "", "" },
587 };
588 
589 /*
590  * Test for hitting a hw access breakpoint
591  */
592 static struct test_struct hw_access_break_test[] = {
593 	{ "?", "S0*" }, /* Clear break points */
594 	{ "hw_break_val", "OK", hw_access_break, }, /* set hw breakpoint */
595 	{ "c", "T0*", NULL, got_break }, /* Continue */
596 	{ "g", "silent", NULL, check_and_rewind_pc },
597 	{ "write", "OK", write_regs },
598 	{ "hw_break_val", "OK", hw_rem_access_break }, /*remove breakpoint */
599 	{ "D", "OK" }, /* Detach */
600 	{ "D", "OK", NULL,  got_break }, /* On success we made it here */
601 	{ "", "" },
602 };
603 
604 /*
605  * Test for hitting a hw access breakpoint
606  */
607 static struct test_struct nmi_sleep_test[] = {
608 	{ "?", "S0*" }, /* Clear break points */
609 	{ "c", "T0*", NULL, got_break }, /* Continue */
610 	{ "D", "OK" }, /* Detach */
611 	{ "D", "OK", NULL,  got_break }, /* On success we made it here */
612 	{ "", "" },
613 };
614 
615 static void fill_get_buf(char *buf)
616 {
617 	unsigned char checksum = 0;
618 	int count = 0;
619 	char ch;
620 
621 	strcpy(get_buf, "$");
622 	strcat(get_buf, buf);
623 	while ((ch = buf[count])) {
624 		checksum += ch;
625 		count++;
626 	}
627 	strcat(get_buf, "#");
628 	get_buf[count + 2] = hex_asc_hi(checksum);
629 	get_buf[count + 3] = hex_asc_lo(checksum);
630 	get_buf[count + 4] = '\0';
631 	v2printk("get%i: %s\n", ts.idx, get_buf);
632 }
633 
634 static int validate_simple_test(char *put_str)
635 {
636 	char *chk_str;
637 
638 	if (ts.tst[ts.idx].put_handler)
639 		return ts.tst[ts.idx].put_handler(put_str,
640 			ts.tst[ts.idx].put);
641 
642 	chk_str = ts.tst[ts.idx].put;
643 	if (*put_str == '$')
644 		put_str++;
645 
646 	while (*chk_str != '\0' && *put_str != '\0') {
647 		/* If someone does a * to match the rest of the string, allow
648 		 * it, or stop if the recieved string is complete.
649 		 */
650 		if (*put_str == '#' || *chk_str == '*')
651 			return 0;
652 		if (*put_str != *chk_str)
653 			return 1;
654 
655 		chk_str++;
656 		put_str++;
657 	}
658 	if (*chk_str == '\0' && (*put_str == '\0' || *put_str == '#'))
659 		return 0;
660 
661 	return 1;
662 }
663 
664 static int run_simple_test(int is_get_char, int chr)
665 {
666 	int ret = 0;
667 	if (is_get_char) {
668 		/* Send an ACK on the get if a prior put completed and set the
669 		 * send ack variable
670 		 */
671 		if (send_ack) {
672 			send_ack = 0;
673 			return '+';
674 		}
675 		/* On the first get char, fill the transmit buffer and then
676 		 * take from the get_string.
677 		 */
678 		if (get_buf_cnt == 0) {
679 			if (ts.tst[ts.idx].get_handler)
680 				ts.tst[ts.idx].get_handler(ts.tst[ts.idx].get);
681 			else
682 				fill_get_buf(ts.tst[ts.idx].get);
683 		}
684 
685 		if (get_buf[get_buf_cnt] == '\0') {
686 			eprintk("kgdbts: ERROR GET: EOB on '%s' at %i\n",
687 			   ts.name, ts.idx);
688 			get_buf_cnt = 0;
689 			fill_get_buf("D");
690 		}
691 		ret = get_buf[get_buf_cnt];
692 		get_buf_cnt++;
693 		return ret;
694 	}
695 
696 	/* This callback is a put char which is when kgdb sends data to
697 	 * this I/O module.
698 	 */
699 	if (ts.tst[ts.idx].get[0] == '\0' &&
700 		ts.tst[ts.idx].put[0] == '\0') {
701 		eprintk("kgdbts: ERROR: beyond end of test on"
702 			   " '%s' line %i\n", ts.name, ts.idx);
703 		return 0;
704 	}
705 
706 	if (put_buf_cnt >= BUFMAX) {
707 		eprintk("kgdbts: ERROR: put buffer overflow on"
708 			   " '%s' line %i\n", ts.name, ts.idx);
709 		put_buf_cnt = 0;
710 		return 0;
711 	}
712 	/* Ignore everything until the first valid packet start '$' */
713 	if (put_buf_cnt == 0 && chr != '$')
714 		return 0;
715 
716 	put_buf[put_buf_cnt] = chr;
717 	put_buf_cnt++;
718 
719 	/* End of packet == #XX so look for the '#' */
720 	if (put_buf_cnt > 3 && put_buf[put_buf_cnt - 3] == '#') {
721 		if (put_buf_cnt >= BUFMAX) {
722 			eprintk("kgdbts: ERROR: put buffer overflow on"
723 				" '%s' line %i\n", ts.name, ts.idx);
724 			put_buf_cnt = 0;
725 			return 0;
726 		}
727 		put_buf[put_buf_cnt] = '\0';
728 		v2printk("put%i: %s\n", ts.idx, put_buf);
729 		/* Trigger check here */
730 		if (ts.validate_put && ts.validate_put(put_buf)) {
731 			eprintk("kgdbts: ERROR PUT: end of test "
732 			   "buffer on '%s' line %i expected %s got %s\n",
733 			   ts.name, ts.idx, ts.tst[ts.idx].put, put_buf);
734 		}
735 		ts.idx++;
736 		put_buf_cnt = 0;
737 		get_buf_cnt = 0;
738 		send_ack = 1;
739 	}
740 	return 0;
741 }
742 
743 static void init_simple_test(void)
744 {
745 	memset(&ts, 0, sizeof(ts));
746 	ts.run_test = run_simple_test;
747 	ts.validate_put = validate_simple_test;
748 }
749 
750 static void run_plant_and_detach_test(int is_early)
751 {
752 	char before[BREAK_INSTR_SIZE];
753 	char after[BREAK_INSTR_SIZE];
754 
755 	probe_kernel_read(before, (char *)kgdbts_break_test,
756 	  BREAK_INSTR_SIZE);
757 	init_simple_test();
758 	ts.tst = plant_and_detach_test;
759 	ts.name = "plant_and_detach_test";
760 	/* Activate test with initial breakpoint */
761 	if (!is_early)
762 		kgdb_breakpoint();
763 	probe_kernel_read(after, (char *)kgdbts_break_test,
764 	  BREAK_INSTR_SIZE);
765 	if (memcmp(before, after, BREAK_INSTR_SIZE)) {
766 		printk(KERN_CRIT "kgdbts: ERROR kgdb corrupted memory\n");
767 		panic("kgdb memory corruption");
768 	}
769 
770 	/* complete the detach test */
771 	if (!is_early)
772 		kgdbts_break_test();
773 }
774 
775 static void run_breakpoint_test(int is_hw_breakpoint)
776 {
777 	test_complete = 0;
778 	init_simple_test();
779 	if (is_hw_breakpoint) {
780 		ts.tst = hw_breakpoint_test;
781 		ts.name = "hw_breakpoint_test";
782 	} else {
783 		ts.tst = sw_breakpoint_test;
784 		ts.name = "sw_breakpoint_test";
785 	}
786 	/* Activate test with initial breakpoint */
787 	kgdb_breakpoint();
788 	/* run code with the break point in it */
789 	kgdbts_break_test();
790 	kgdb_breakpoint();
791 
792 	if (test_complete)
793 		return;
794 
795 	eprintk("kgdbts: ERROR %s test failed\n", ts.name);
796 	if (is_hw_breakpoint)
797 		hwbreaks_ok = 0;
798 }
799 
800 static void run_hw_break_test(int is_write_test)
801 {
802 	test_complete = 0;
803 	init_simple_test();
804 	if (is_write_test) {
805 		ts.tst = hw_write_break_test;
806 		ts.name = "hw_write_break_test";
807 	} else {
808 		ts.tst = hw_access_break_test;
809 		ts.name = "hw_access_break_test";
810 	}
811 	/* Activate test with initial breakpoint */
812 	kgdb_breakpoint();
813 	hw_break_val_access();
814 	if (is_write_test) {
815 		if (test_complete == 2) {
816 			eprintk("kgdbts: ERROR %s broke on access\n",
817 				ts.name);
818 			hwbreaks_ok = 0;
819 		}
820 		hw_break_val_write();
821 	}
822 	kgdb_breakpoint();
823 
824 	if (test_complete == 1)
825 		return;
826 
827 	eprintk("kgdbts: ERROR %s test failed\n", ts.name);
828 	hwbreaks_ok = 0;
829 }
830 
831 static void run_nmi_sleep_test(int nmi_sleep)
832 {
833 	unsigned long flags;
834 
835 	init_simple_test();
836 	ts.tst = nmi_sleep_test;
837 	ts.name = "nmi_sleep_test";
838 	/* Activate test with initial breakpoint */
839 	kgdb_breakpoint();
840 	local_irq_save(flags);
841 	mdelay(nmi_sleep*1000);
842 	touch_nmi_watchdog();
843 	local_irq_restore(flags);
844 	if (test_complete != 2)
845 		eprintk("kgdbts: ERROR nmi_test did not hit nmi\n");
846 	kgdb_breakpoint();
847 	if (test_complete == 1)
848 		return;
849 
850 	eprintk("kgdbts: ERROR %s test failed\n", ts.name);
851 }
852 
853 static void run_bad_read_test(void)
854 {
855 	init_simple_test();
856 	ts.tst = bad_read_test;
857 	ts.name = "bad_read_test";
858 	/* Activate test with initial breakpoint */
859 	kgdb_breakpoint();
860 }
861 
862 static void run_do_fork_test(void)
863 {
864 	init_simple_test();
865 	ts.tst = do_fork_test;
866 	ts.name = "do_fork_test";
867 	/* Activate test with initial breakpoint */
868 	kgdb_breakpoint();
869 }
870 
871 static void run_sys_open_test(void)
872 {
873 	init_simple_test();
874 	ts.tst = sys_open_test;
875 	ts.name = "sys_open_test";
876 	/* Activate test with initial breakpoint */
877 	kgdb_breakpoint();
878 }
879 
880 static void run_singlestep_break_test(void)
881 {
882 	init_simple_test();
883 	ts.tst = singlestep_break_test;
884 	ts.name = "singlestep_breakpoint_test";
885 	/* Activate test with initial breakpoint */
886 	kgdb_breakpoint();
887 	kgdbts_break_test();
888 	kgdbts_break_test();
889 }
890 
891 static void kgdbts_run_tests(void)
892 {
893 	char *ptr;
894 	int fork_test = 0;
895 	int do_sys_open_test = 0;
896 	int sstep_test = 1000;
897 	int nmi_sleep = 0;
898 	int i;
899 
900 	ptr = strchr(config, 'F');
901 	if (ptr)
902 		fork_test = simple_strtol(ptr + 1, NULL, 10);
903 	ptr = strchr(config, 'S');
904 	if (ptr)
905 		do_sys_open_test = simple_strtol(ptr + 1, NULL, 10);
906 	ptr = strchr(config, 'N');
907 	if (ptr)
908 		nmi_sleep = simple_strtol(ptr+1, NULL, 10);
909 	ptr = strchr(config, 'I');
910 	if (ptr)
911 		sstep_test = simple_strtol(ptr+1, NULL, 10);
912 
913 	/* required internal KGDB tests */
914 	v1printk("kgdbts:RUN plant and detach test\n");
915 	run_plant_and_detach_test(0);
916 	v1printk("kgdbts:RUN sw breakpoint test\n");
917 	run_breakpoint_test(0);
918 	v1printk("kgdbts:RUN bad memory access test\n");
919 	run_bad_read_test();
920 	v1printk("kgdbts:RUN singlestep test %i iterations\n", sstep_test);
921 	for (i = 0; i < sstep_test; i++) {
922 		run_singlestep_break_test();
923 		if (i % 100 == 0)
924 			v1printk("kgdbts:RUN singlestep [%i/%i]\n",
925 				 i, sstep_test);
926 	}
927 
928 	/* ===Optional tests=== */
929 
930 	/* All HW break point tests */
931 	if (arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT) {
932 		hwbreaks_ok = 1;
933 		v1printk("kgdbts:RUN hw breakpoint test\n");
934 		run_breakpoint_test(1);
935 		v1printk("kgdbts:RUN hw write breakpoint test\n");
936 		run_hw_break_test(1);
937 		v1printk("kgdbts:RUN access write breakpoint test\n");
938 		run_hw_break_test(0);
939 	}
940 
941 	if (nmi_sleep) {
942 		v1printk("kgdbts:RUN NMI sleep %i seconds test\n", nmi_sleep);
943 		run_nmi_sleep_test(nmi_sleep);
944 	}
945 
946 #ifdef CONFIG_DEBUG_RODATA
947 	/* Until there is an api to write to read-only text segments, use
948 	 * HW breakpoints for the remainder of any tests, else print a
949 	 * failure message if hw breakpoints do not work.
950 	 */
951 	if (!(arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT && hwbreaks_ok)) {
952 		eprintk("kgdbts: HW breakpoints do not work,"
953 			"skipping remaining tests\n");
954 		return;
955 	}
956 	force_hwbrks = 1;
957 #endif /* CONFIG_DEBUG_RODATA */
958 
959 	/* If the do_fork test is run it will be the last test that is
960 	 * executed because a kernel thread will be spawned at the very
961 	 * end to unregister the debug hooks.
962 	 */
963 	if (fork_test) {
964 		repeat_test = fork_test;
965 		printk(KERN_INFO "kgdbts:RUN do_fork for %i breakpoints\n",
966 			repeat_test);
967 		kthread_run(kgdbts_unreg_thread, NULL, "kgdbts_unreg");
968 		run_do_fork_test();
969 		return;
970 	}
971 
972 	/* If the sys_open test is run it will be the last test that is
973 	 * executed because a kernel thread will be spawned at the very
974 	 * end to unregister the debug hooks.
975 	 */
976 	if (do_sys_open_test) {
977 		repeat_test = do_sys_open_test;
978 		printk(KERN_INFO "kgdbts:RUN sys_open for %i breakpoints\n",
979 			repeat_test);
980 		kthread_run(kgdbts_unreg_thread, NULL, "kgdbts_unreg");
981 		run_sys_open_test();
982 		return;
983 	}
984 	/* Shutdown and unregister */
985 	kgdb_unregister_io_module(&kgdbts_io_ops);
986 	configured = 0;
987 }
988 
989 static int kgdbts_option_setup(char *opt)
990 {
991 	if (strlen(opt) > MAX_CONFIG_LEN) {
992 		printk(KERN_ERR "kgdbts: config string too long\n");
993 		return -ENOSPC;
994 	}
995 	strcpy(config, opt);
996 
997 	verbose = 0;
998 	if (strstr(config, "V1"))
999 		verbose = 1;
1000 	if (strstr(config, "V2"))
1001 		verbose = 2;
1002 
1003 	return 0;
1004 }
1005 
1006 __setup("kgdbts=", kgdbts_option_setup);
1007 
1008 static int configure_kgdbts(void)
1009 {
1010 	int err = 0;
1011 
1012 	if (!strlen(config) || isspace(config[0]))
1013 		goto noconfig;
1014 	err = kgdbts_option_setup(config);
1015 	if (err)
1016 		goto noconfig;
1017 
1018 	final_ack = 0;
1019 	run_plant_and_detach_test(1);
1020 
1021 	err = kgdb_register_io_module(&kgdbts_io_ops);
1022 	if (err) {
1023 		configured = 0;
1024 		return err;
1025 	}
1026 	configured = 1;
1027 	kgdbts_run_tests();
1028 
1029 	return err;
1030 
1031 noconfig:
1032 	config[0] = 0;
1033 	configured = 0;
1034 
1035 	return err;
1036 }
1037 
1038 static int __init init_kgdbts(void)
1039 {
1040 	/* Already configured? */
1041 	if (configured == 1)
1042 		return 0;
1043 
1044 	return configure_kgdbts();
1045 }
1046 
1047 static void cleanup_kgdbts(void)
1048 {
1049 	if (configured == 1)
1050 		kgdb_unregister_io_module(&kgdbts_io_ops);
1051 }
1052 
1053 static int kgdbts_get_char(void)
1054 {
1055 	int val = 0;
1056 
1057 	if (ts.run_test)
1058 		val = ts.run_test(1, 0);
1059 
1060 	return val;
1061 }
1062 
1063 static void kgdbts_put_char(u8 chr)
1064 {
1065 	if (ts.run_test)
1066 		ts.run_test(0, chr);
1067 }
1068 
1069 static int param_set_kgdbts_var(const char *kmessage, struct kernel_param *kp)
1070 {
1071 	int len = strlen(kmessage);
1072 
1073 	if (len >= MAX_CONFIG_LEN) {
1074 		printk(KERN_ERR "kgdbts: config string too long\n");
1075 		return -ENOSPC;
1076 	}
1077 
1078 	/* Only copy in the string if the init function has not run yet */
1079 	if (configured < 0) {
1080 		strcpy(config, kmessage);
1081 		return 0;
1082 	}
1083 
1084 	if (kgdb_connected) {
1085 		printk(KERN_ERR
1086 	       "kgdbts: Cannot reconfigure while KGDB is connected.\n");
1087 
1088 		return -EBUSY;
1089 	}
1090 
1091 	strcpy(config, kmessage);
1092 	/* Chop out \n char as a result of echo */
1093 	if (config[len - 1] == '\n')
1094 		config[len - 1] = '\0';
1095 
1096 	if (configured == 1)
1097 		cleanup_kgdbts();
1098 
1099 	/* Go and configure with the new params. */
1100 	return configure_kgdbts();
1101 }
1102 
1103 static void kgdbts_pre_exp_handler(void)
1104 {
1105 	/* Increment the module count when the debugger is active */
1106 	if (!kgdb_connected)
1107 		try_module_get(THIS_MODULE);
1108 }
1109 
1110 static void kgdbts_post_exp_handler(void)
1111 {
1112 	/* decrement the module count when the debugger detaches */
1113 	if (!kgdb_connected)
1114 		module_put(THIS_MODULE);
1115 }
1116 
1117 static struct kgdb_io kgdbts_io_ops = {
1118 	.name			= "kgdbts",
1119 	.read_char		= kgdbts_get_char,
1120 	.write_char		= kgdbts_put_char,
1121 	.pre_exception		= kgdbts_pre_exp_handler,
1122 	.post_exception		= kgdbts_post_exp_handler,
1123 };
1124 
1125 module_init(init_kgdbts);
1126 module_exit(cleanup_kgdbts);
1127 module_param_call(kgdbts, param_set_kgdbts_var, param_get_string, &kps, 0644);
1128 MODULE_PARM_DESC(kgdbts, "<A|V1|V2>[F#|S#][N#]");
1129 MODULE_DESCRIPTION("KGDB Test Suite");
1130 MODULE_LICENSE("GPL");
1131 MODULE_AUTHOR("Wind River Systems, Inc.");
1132 
1133