xref: /openbmc/linux/arch/powerpc/xmon/xmon.c (revision 2fa49589)
1 /*
2  * Routines providing a simple monitor for use on the PowerMac.
3  *
4  * Copyright (C) 1996-2005 Paul Mackerras.
5  * Copyright (C) 2001 PPC64 Team, IBM Corp
6  * Copyrignt (C) 2006 Michael Ellerman, IBM Corp
7  *
8  *      This program is free software; you can redistribute it and/or
9  *      modify it under the terms of the GNU General Public License
10  *      as published by the Free Software Foundation; either version
11  *      2 of the License, or (at your option) any later version.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/sched/signal.h>
17 #include <linux/smp.h>
18 #include <linux/mm.h>
19 #include <linux/reboot.h>
20 #include <linux/delay.h>
21 #include <linux/kallsyms.h>
22 #include <linux/kmsg_dump.h>
23 #include <linux/cpumask.h>
24 #include <linux/export.h>
25 #include <linux/sysrq.h>
26 #include <linux/interrupt.h>
27 #include <linux/irq.h>
28 #include <linux/bug.h>
29 #include <linux/nmi.h>
30 #include <linux/ctype.h>
31 #include <linux/highmem.h>
32 
33 #include <asm/debugfs.h>
34 #include <asm/ptrace.h>
35 #include <asm/smp.h>
36 #include <asm/string.h>
37 #include <asm/prom.h>
38 #include <asm/machdep.h>
39 #include <asm/xmon.h>
40 #include <asm/processor.h>
41 #include <asm/pgtable.h>
42 #include <asm/mmu.h>
43 #include <asm/mmu_context.h>
44 #include <asm/plpar_wrappers.h>
45 #include <asm/cputable.h>
46 #include <asm/rtas.h>
47 #include <asm/sstep.h>
48 #include <asm/irq_regs.h>
49 #include <asm/spu.h>
50 #include <asm/spu_priv1.h>
51 #include <asm/setjmp.h>
52 #include <asm/reg.h>
53 #include <asm/debug.h>
54 #include <asm/hw_breakpoint.h>
55 #include <asm/xive.h>
56 #include <asm/opal.h>
57 #include <asm/firmware.h>
58 #include <asm/code-patching.h>
59 #include <asm/sections.h>
60 
61 #ifdef CONFIG_PPC64
62 #include <asm/hvcall.h>
63 #include <asm/paca.h>
64 #endif
65 
66 #include "nonstdio.h"
67 #include "dis-asm.h"
68 
69 #ifdef CONFIG_SMP
70 static cpumask_t cpus_in_xmon = CPU_MASK_NONE;
71 static unsigned long xmon_taken = 1;
72 static int xmon_owner;
73 static int xmon_gate;
74 #else
75 #define xmon_owner 0
76 #endif /* CONFIG_SMP */
77 
78 #ifdef CONFIG_PPC_PSERIES
79 static int set_indicator_token = RTAS_UNKNOWN_SERVICE;
80 #endif
81 static unsigned long in_xmon __read_mostly = 0;
82 static int xmon_on = IS_ENABLED(CONFIG_XMON_DEFAULT);
83 
84 static unsigned long adrs;
85 static int size = 1;
86 #define MAX_DUMP (128 * 1024)
87 static unsigned long ndump = 64;
88 static unsigned long nidump = 16;
89 static unsigned long ncsum = 4096;
90 static int termch;
91 static char tmpstr[128];
92 static int tracing_enabled;
93 
94 static long bus_error_jmp[JMP_BUF_LEN];
95 static int catch_memory_errors;
96 static int catch_spr_faults;
97 static long *xmon_fault_jmp[NR_CPUS];
98 
99 /* Breakpoint stuff */
100 struct bpt {
101 	unsigned long	address;
102 	unsigned int	instr[2];
103 	atomic_t	ref_count;
104 	int		enabled;
105 	unsigned long	pad;
106 };
107 
108 /* Bits in bpt.enabled */
109 #define BP_CIABR	1
110 #define BP_TRAP		2
111 #define BP_DABR		4
112 
113 #define NBPTS	256
114 static struct bpt bpts[NBPTS];
115 static struct bpt dabr;
116 static struct bpt *iabr;
117 static unsigned bpinstr = 0x7fe00008;	/* trap */
118 
119 #define BP_NUM(bp)	((bp) - bpts + 1)
120 
121 /* Prototypes */
122 static int cmds(struct pt_regs *);
123 static int mread(unsigned long, void *, int);
124 static int mwrite(unsigned long, void *, int);
125 static int handle_fault(struct pt_regs *);
126 static void byterev(unsigned char *, int);
127 static void memex(void);
128 static int bsesc(void);
129 static void dump(void);
130 static void show_pte(unsigned long);
131 static void prdump(unsigned long, long);
132 static int ppc_inst_dump(unsigned long, long, int);
133 static void dump_log_buf(void);
134 
135 #ifdef CONFIG_PPC_POWERNV
136 static void dump_opal_msglog(void);
137 #else
138 static inline void dump_opal_msglog(void)
139 {
140 	printf("Machine is not running OPAL firmware.\n");
141 }
142 #endif
143 
144 static void backtrace(struct pt_regs *);
145 static void excprint(struct pt_regs *);
146 static void prregs(struct pt_regs *);
147 static void memops(int);
148 static void memlocate(void);
149 static void memzcan(void);
150 static void memdiffs(unsigned char *, unsigned char *, unsigned, unsigned);
151 int skipbl(void);
152 int scanhex(unsigned long *valp);
153 static void scannl(void);
154 static int hexdigit(int);
155 void getstring(char *, int);
156 static void flush_input(void);
157 static int inchar(void);
158 static void take_input(char *);
159 static int  read_spr(int, unsigned long *);
160 static void write_spr(int, unsigned long);
161 static void super_regs(void);
162 static void remove_bpts(void);
163 static void insert_bpts(void);
164 static void remove_cpu_bpts(void);
165 static void insert_cpu_bpts(void);
166 static struct bpt *at_breakpoint(unsigned long pc);
167 static struct bpt *in_breakpoint_table(unsigned long pc, unsigned long *offp);
168 static int  do_step(struct pt_regs *);
169 static void bpt_cmds(void);
170 static void cacheflush(void);
171 static int  cpu_cmd(void);
172 static void csum(void);
173 static void bootcmds(void);
174 static void proccall(void);
175 static void show_tasks(void);
176 void dump_segments(void);
177 static void symbol_lookup(void);
178 static void xmon_show_stack(unsigned long sp, unsigned long lr,
179 			    unsigned long pc);
180 static void xmon_print_symbol(unsigned long address, const char *mid,
181 			      const char *after);
182 static const char *getvecname(unsigned long vec);
183 
184 static int do_spu_cmd(void);
185 
186 #ifdef CONFIG_44x
187 static void dump_tlb_44x(void);
188 #endif
189 #ifdef CONFIG_PPC_BOOK3E
190 static void dump_tlb_book3e(void);
191 #endif
192 
193 #ifdef CONFIG_PPC64
194 #define REG		"%.16lx"
195 #else
196 #define REG		"%.8lx"
197 #endif
198 
199 #ifdef __LITTLE_ENDIAN__
200 #define GETWORD(v)	(((v)[3] << 24) + ((v)[2] << 16) + ((v)[1] << 8) + (v)[0])
201 #else
202 #define GETWORD(v)	(((v)[0] << 24) + ((v)[1] << 16) + ((v)[2] << 8) + (v)[3])
203 #endif
204 
205 static char *help_string = "\
206 Commands:\n\
207   b	show breakpoints\n\
208   bd	set data breakpoint\n\
209   bi	set instruction breakpoint\n\
210   bc	clear breakpoint\n"
211 #ifdef CONFIG_SMP
212   "\
213   c	print cpus stopped in xmon\n\
214   c#	try to switch to cpu number h (in hex)\n"
215 #endif
216   "\
217   C	checksum\n\
218   d	dump bytes\n\
219   d1	dump 1 byte values\n\
220   d2	dump 2 byte values\n\
221   d4	dump 4 byte values\n\
222   d8	dump 8 byte values\n\
223   di	dump instructions\n\
224   df	dump float values\n\
225   dd	dump double values\n\
226   dl    dump the kernel log buffer\n"
227 #ifdef CONFIG_PPC_POWERNV
228   "\
229   do    dump the OPAL message log\n"
230 #endif
231 #ifdef CONFIG_PPC64
232   "\
233   dp[#]	dump paca for current cpu, or cpu #\n\
234   dpa	dump paca for all possible cpus\n"
235 #endif
236   "\
237   dr	dump stream of raw bytes\n\
238   dv	dump virtual address translation \n\
239   dt	dump the tracing buffers (uses printk)\n\
240   dtc	dump the tracing buffers for current CPU (uses printk)\n\
241 "
242 #ifdef CONFIG_PPC_POWERNV
243 "  dx#   dump xive on CPU #\n\
244   dxi#  dump xive irq state #\n\
245   dxa   dump xive on all CPUs\n"
246 #endif
247 "  e	print exception information\n\
248   f	flush cache\n\
249   la	lookup symbol+offset of specified address\n\
250   ls	lookup address of specified symbol\n\
251   lp s [#]	lookup address of percpu symbol s for current cpu, or cpu #\n\
252   m	examine/change memory\n\
253   mm	move a block of memory\n\
254   ms	set a block of memory\n\
255   md	compare two blocks of memory\n\
256   ml	locate a block of memory\n\
257   mz	zero a block of memory\n\
258   mi	show information about memory allocation\n\
259   p 	call a procedure\n\
260   P 	list processes/tasks\n\
261   r	print registers\n\
262   s	single step\n"
263 #ifdef CONFIG_SPU_BASE
264 "  ss	stop execution on all spus\n\
265   sr	restore execution on stopped spus\n\
266   sf  #	dump spu fields for spu # (in hex)\n\
267   sd  #	dump spu local store for spu # (in hex)\n\
268   sdi #	disassemble spu local store for spu # (in hex)\n"
269 #endif
270 "  S	print special registers\n\
271   Sa    print all SPRs\n\
272   Sr #	read SPR #\n\
273   Sw #v write v to SPR #\n\
274   t	print backtrace\n\
275   x	exit monitor and recover\n\
276   X	exit monitor and don't recover\n"
277 #if defined(CONFIG_PPC64) && !defined(CONFIG_PPC_BOOK3E)
278 "  u	dump segment table or SLB\n"
279 #elif defined(CONFIG_PPC_BOOK3S_32)
280 "  u	dump segment registers\n"
281 #elif defined(CONFIG_44x) || defined(CONFIG_PPC_BOOK3E)
282 "  u	dump TLB\n"
283 #endif
284 "  U	show uptime information\n"
285 "  ?	help\n"
286 "  # n	limit output to n lines per page (for dp, dpa, dl)\n"
287 "  zr	reboot\n\
288   zh	halt\n"
289 ;
290 
291 static struct pt_regs *xmon_regs;
292 
293 static inline void sync(void)
294 {
295 	asm volatile("sync; isync");
296 }
297 
298 static inline void store_inst(void *p)
299 {
300 	asm volatile ("dcbst 0,%0; sync; icbi 0,%0; isync" : : "r" (p));
301 }
302 
303 static inline void cflush(void *p)
304 {
305 	asm volatile ("dcbf 0,%0; icbi 0,%0" : : "r" (p));
306 }
307 
308 static inline void cinval(void *p)
309 {
310 	asm volatile ("dcbi 0,%0; icbi 0,%0" : : "r" (p));
311 }
312 
313 /**
314  * write_ciabr() - write the CIABR SPR
315  * @ciabr:	The value to write.
316  *
317  * This function writes a value to the CIARB register either directly
318  * through mtspr instruction if the kernel is in HV privilege mode or
319  * call a hypervisor function to achieve the same in case the kernel
320  * is in supervisor privilege mode.
321  */
322 static void write_ciabr(unsigned long ciabr)
323 {
324 	if (!cpu_has_feature(CPU_FTR_ARCH_207S))
325 		return;
326 
327 	if (cpu_has_feature(CPU_FTR_HVMODE)) {
328 		mtspr(SPRN_CIABR, ciabr);
329 		return;
330 	}
331 	plpar_set_ciabr(ciabr);
332 }
333 
334 /**
335  * set_ciabr() - set the CIABR
336  * @addr:	The value to set.
337  *
338  * This function sets the correct privilege value into the the HW
339  * breakpoint address before writing it up in the CIABR register.
340  */
341 static void set_ciabr(unsigned long addr)
342 {
343 	addr &= ~CIABR_PRIV;
344 
345 	if (cpu_has_feature(CPU_FTR_HVMODE))
346 		addr |= CIABR_PRIV_HYPER;
347 	else
348 		addr |= CIABR_PRIV_SUPER;
349 	write_ciabr(addr);
350 }
351 
352 /*
353  * Disable surveillance (the service processor watchdog function)
354  * while we are in xmon.
355  * XXX we should re-enable it when we leave. :)
356  */
357 #define SURVEILLANCE_TOKEN	9000
358 
359 static inline void disable_surveillance(void)
360 {
361 #ifdef CONFIG_PPC_PSERIES
362 	/* Since this can't be a module, args should end up below 4GB. */
363 	static struct rtas_args args;
364 
365 	/*
366 	 * At this point we have got all the cpus we can into
367 	 * xmon, so there is hopefully no other cpu calling RTAS
368 	 * at the moment, even though we don't take rtas.lock.
369 	 * If we did try to take rtas.lock there would be a
370 	 * real possibility of deadlock.
371 	 */
372 	if (set_indicator_token == RTAS_UNKNOWN_SERVICE)
373 		return;
374 
375 	rtas_call_unlocked(&args, set_indicator_token, 3, 1, NULL,
376 			   SURVEILLANCE_TOKEN, 0, 0);
377 
378 #endif /* CONFIG_PPC_PSERIES */
379 }
380 
381 #ifdef CONFIG_SMP
382 static int xmon_speaker;
383 
384 static void get_output_lock(void)
385 {
386 	int me = smp_processor_id() + 0x100;
387 	int last_speaker = 0, prev;
388 	long timeout;
389 
390 	if (xmon_speaker == me)
391 		return;
392 
393 	for (;;) {
394 		last_speaker = cmpxchg(&xmon_speaker, 0, me);
395 		if (last_speaker == 0)
396 			return;
397 
398 		/*
399 		 * Wait a full second for the lock, we might be on a slow
400 		 * console, but check every 100us.
401 		 */
402 		timeout = 10000;
403 		while (xmon_speaker == last_speaker) {
404 			if (--timeout > 0) {
405 				udelay(100);
406 				continue;
407 			}
408 
409 			/* hostile takeover */
410 			prev = cmpxchg(&xmon_speaker, last_speaker, me);
411 			if (prev == last_speaker)
412 				return;
413 			break;
414 		}
415 	}
416 }
417 
418 static void release_output_lock(void)
419 {
420 	xmon_speaker = 0;
421 }
422 
423 int cpus_are_in_xmon(void)
424 {
425 	return !cpumask_empty(&cpus_in_xmon);
426 }
427 
428 static bool wait_for_other_cpus(int ncpus)
429 {
430 	unsigned long timeout;
431 
432 	/* We wait for 2s, which is a metric "little while" */
433 	for (timeout = 20000; timeout != 0; --timeout) {
434 		if (cpumask_weight(&cpus_in_xmon) >= ncpus)
435 			return true;
436 		udelay(100);
437 		barrier();
438 	}
439 
440 	return false;
441 }
442 #endif /* CONFIG_SMP */
443 
444 static inline int unrecoverable_excp(struct pt_regs *regs)
445 {
446 #if defined(CONFIG_4xx) || defined(CONFIG_PPC_BOOK3E)
447 	/* We have no MSR_RI bit on 4xx or Book3e, so we simply return false */
448 	return 0;
449 #else
450 	return ((regs->msr & MSR_RI) == 0);
451 #endif
452 }
453 
454 static int xmon_core(struct pt_regs *regs, int fromipi)
455 {
456 	int cmd = 0;
457 	struct bpt *bp;
458 	long recurse_jmp[JMP_BUF_LEN];
459 	unsigned long offset;
460 	unsigned long flags;
461 #ifdef CONFIG_SMP
462 	int cpu;
463 	int secondary;
464 #endif
465 
466 	local_irq_save(flags);
467 	hard_irq_disable();
468 
469 	tracing_enabled = tracing_is_on();
470 	tracing_off();
471 
472 	bp = in_breakpoint_table(regs->nip, &offset);
473 	if (bp != NULL) {
474 		regs->nip = bp->address + offset;
475 		atomic_dec(&bp->ref_count);
476 	}
477 
478 	remove_cpu_bpts();
479 
480 #ifdef CONFIG_SMP
481 	cpu = smp_processor_id();
482 	if (cpumask_test_cpu(cpu, &cpus_in_xmon)) {
483 		/*
484 		 * We catch SPR read/write faults here because the 0x700, 0xf60
485 		 * etc. handlers don't call debugger_fault_handler().
486 		 */
487 		if (catch_spr_faults)
488 			longjmp(bus_error_jmp, 1);
489 		get_output_lock();
490 		excprint(regs);
491 		printf("cpu 0x%x: Exception %lx %s in xmon, "
492 		       "returning to main loop\n",
493 		       cpu, regs->trap, getvecname(TRAP(regs)));
494 		release_output_lock();
495 		longjmp(xmon_fault_jmp[cpu], 1);
496 	}
497 
498 	if (setjmp(recurse_jmp) != 0) {
499 		if (!in_xmon || !xmon_gate) {
500 			get_output_lock();
501 			printf("xmon: WARNING: bad recursive fault "
502 			       "on cpu 0x%x\n", cpu);
503 			release_output_lock();
504 			goto waiting;
505 		}
506 		secondary = !(xmon_taken && cpu == xmon_owner);
507 		goto cmdloop;
508 	}
509 
510 	xmon_fault_jmp[cpu] = recurse_jmp;
511 
512 	bp = NULL;
513 	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) == (MSR_IR|MSR_64BIT))
514 		bp = at_breakpoint(regs->nip);
515 	if (bp || unrecoverable_excp(regs))
516 		fromipi = 0;
517 
518 	if (!fromipi) {
519 		get_output_lock();
520 		excprint(regs);
521 		if (bp) {
522 			printf("cpu 0x%x stopped at breakpoint 0x%tx (",
523 			       cpu, BP_NUM(bp));
524 			xmon_print_symbol(regs->nip, " ", ")\n");
525 		}
526 		if (unrecoverable_excp(regs))
527 			printf("WARNING: exception is not recoverable, "
528 			       "can't continue\n");
529 		release_output_lock();
530 	}
531 
532 	cpumask_set_cpu(cpu, &cpus_in_xmon);
533 
534  waiting:
535 	secondary = 1;
536 	spin_begin();
537 	while (secondary && !xmon_gate) {
538 		if (in_xmon == 0) {
539 			if (fromipi) {
540 				spin_end();
541 				goto leave;
542 			}
543 			secondary = test_and_set_bit(0, &in_xmon);
544 		}
545 		spin_cpu_relax();
546 		touch_nmi_watchdog();
547 	}
548 	spin_end();
549 
550 	if (!secondary && !xmon_gate) {
551 		/* we are the first cpu to come in */
552 		/* interrupt other cpu(s) */
553 		int ncpus = num_online_cpus();
554 
555 		xmon_owner = cpu;
556 		mb();
557 		if (ncpus > 1) {
558 			/*
559 			 * A system reset (trap == 0x100) can be triggered on
560 			 * all CPUs, so when we come in via 0x100 try waiting
561 			 * for the other CPUs to come in before we send the
562 			 * debugger break (IPI). This is similar to
563 			 * crash_kexec_secondary().
564 			 */
565 			if (TRAP(regs) != 0x100 || !wait_for_other_cpus(ncpus))
566 				smp_send_debugger_break();
567 
568 			wait_for_other_cpus(ncpus);
569 		}
570 		remove_bpts();
571 		disable_surveillance();
572 		/* for breakpoint or single step, print the current instr. */
573 		if (bp || TRAP(regs) == 0xd00)
574 			ppc_inst_dump(regs->nip, 1, 0);
575 		printf("enter ? for help\n");
576 		mb();
577 		xmon_gate = 1;
578 		barrier();
579 		touch_nmi_watchdog();
580 	}
581 
582  cmdloop:
583 	while (in_xmon) {
584 		if (secondary) {
585 			spin_begin();
586 			if (cpu == xmon_owner) {
587 				if (!test_and_set_bit(0, &xmon_taken)) {
588 					secondary = 0;
589 					spin_end();
590 					continue;
591 				}
592 				/* missed it */
593 				while (cpu == xmon_owner)
594 					spin_cpu_relax();
595 			}
596 			spin_cpu_relax();
597 			touch_nmi_watchdog();
598 		} else {
599 			cmd = cmds(regs);
600 			if (cmd != 0) {
601 				/* exiting xmon */
602 				insert_bpts();
603 				xmon_gate = 0;
604 				wmb();
605 				in_xmon = 0;
606 				break;
607 			}
608 			/* have switched to some other cpu */
609 			secondary = 1;
610 		}
611 	}
612  leave:
613 	cpumask_clear_cpu(cpu, &cpus_in_xmon);
614 	xmon_fault_jmp[cpu] = NULL;
615 #else
616 	/* UP is simple... */
617 	if (in_xmon) {
618 		printf("Exception %lx %s in xmon, returning to main loop\n",
619 		       regs->trap, getvecname(TRAP(regs)));
620 		longjmp(xmon_fault_jmp[0], 1);
621 	}
622 	if (setjmp(recurse_jmp) == 0) {
623 		xmon_fault_jmp[0] = recurse_jmp;
624 		in_xmon = 1;
625 
626 		excprint(regs);
627 		bp = at_breakpoint(regs->nip);
628 		if (bp) {
629 			printf("Stopped at breakpoint %tx (", BP_NUM(bp));
630 			xmon_print_symbol(regs->nip, " ", ")\n");
631 		}
632 		if (unrecoverable_excp(regs))
633 			printf("WARNING: exception is not recoverable, "
634 			       "can't continue\n");
635 		remove_bpts();
636 		disable_surveillance();
637 		/* for breakpoint or single step, print the current instr. */
638 		if (bp || TRAP(regs) == 0xd00)
639 			ppc_inst_dump(regs->nip, 1, 0);
640 		printf("enter ? for help\n");
641 	}
642 
643 	cmd = cmds(regs);
644 
645 	insert_bpts();
646 	in_xmon = 0;
647 #endif
648 
649 #ifdef CONFIG_BOOKE
650 	if (regs->msr & MSR_DE) {
651 		bp = at_breakpoint(regs->nip);
652 		if (bp != NULL) {
653 			regs->nip = (unsigned long) &bp->instr[0];
654 			atomic_inc(&bp->ref_count);
655 		}
656 	}
657 #else
658 	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) == (MSR_IR|MSR_64BIT)) {
659 		bp = at_breakpoint(regs->nip);
660 		if (bp != NULL) {
661 			int stepped = emulate_step(regs, bp->instr[0]);
662 			if (stepped == 0) {
663 				regs->nip = (unsigned long) &bp->instr[0];
664 				atomic_inc(&bp->ref_count);
665 			} else if (stepped < 0) {
666 				printf("Couldn't single-step %s instruction\n",
667 				    (IS_RFID(bp->instr[0])? "rfid": "mtmsrd"));
668 			}
669 		}
670 	}
671 #endif
672 	insert_cpu_bpts();
673 
674 	touch_nmi_watchdog();
675 	local_irq_restore(flags);
676 
677 	return cmd != 'X' && cmd != EOF;
678 }
679 
680 int xmon(struct pt_regs *excp)
681 {
682 	struct pt_regs regs;
683 
684 	if (excp == NULL) {
685 		ppc_save_regs(&regs);
686 		excp = &regs;
687 	}
688 
689 	return xmon_core(excp, 0);
690 }
691 EXPORT_SYMBOL(xmon);
692 
693 irqreturn_t xmon_irq(int irq, void *d)
694 {
695 	unsigned long flags;
696 	local_irq_save(flags);
697 	printf("Keyboard interrupt\n");
698 	xmon(get_irq_regs());
699 	local_irq_restore(flags);
700 	return IRQ_HANDLED;
701 }
702 
703 static int xmon_bpt(struct pt_regs *regs)
704 {
705 	struct bpt *bp;
706 	unsigned long offset;
707 
708 	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) != (MSR_IR|MSR_64BIT))
709 		return 0;
710 
711 	/* Are we at the trap at bp->instr[1] for some bp? */
712 	bp = in_breakpoint_table(regs->nip, &offset);
713 	if (bp != NULL && offset == 4) {
714 		regs->nip = bp->address + 4;
715 		atomic_dec(&bp->ref_count);
716 		return 1;
717 	}
718 
719 	/* Are we at a breakpoint? */
720 	bp = at_breakpoint(regs->nip);
721 	if (!bp)
722 		return 0;
723 
724 	xmon_core(regs, 0);
725 
726 	return 1;
727 }
728 
729 static int xmon_sstep(struct pt_regs *regs)
730 {
731 	if (user_mode(regs))
732 		return 0;
733 	xmon_core(regs, 0);
734 	return 1;
735 }
736 
737 static int xmon_break_match(struct pt_regs *regs)
738 {
739 	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) != (MSR_IR|MSR_64BIT))
740 		return 0;
741 	if (dabr.enabled == 0)
742 		return 0;
743 	xmon_core(regs, 0);
744 	return 1;
745 }
746 
747 static int xmon_iabr_match(struct pt_regs *regs)
748 {
749 	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) != (MSR_IR|MSR_64BIT))
750 		return 0;
751 	if (iabr == NULL)
752 		return 0;
753 	xmon_core(regs, 0);
754 	return 1;
755 }
756 
757 static int xmon_ipi(struct pt_regs *regs)
758 {
759 #ifdef CONFIG_SMP
760 	if (in_xmon && !cpumask_test_cpu(smp_processor_id(), &cpus_in_xmon))
761 		xmon_core(regs, 1);
762 #endif
763 	return 0;
764 }
765 
766 static int xmon_fault_handler(struct pt_regs *regs)
767 {
768 	struct bpt *bp;
769 	unsigned long offset;
770 
771 	if (in_xmon && catch_memory_errors)
772 		handle_fault(regs);	/* doesn't return */
773 
774 	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) == (MSR_IR|MSR_64BIT)) {
775 		bp = in_breakpoint_table(regs->nip, &offset);
776 		if (bp != NULL) {
777 			regs->nip = bp->address + offset;
778 			atomic_dec(&bp->ref_count);
779 		}
780 	}
781 
782 	return 0;
783 }
784 
785 /* Force enable xmon if not already enabled */
786 static inline void force_enable_xmon(void)
787 {
788 	/* Enable xmon hooks if needed */
789 	if (!xmon_on) {
790 		printf("xmon: Enabling debugger hooks\n");
791 		xmon_on = 1;
792 	}
793 }
794 
795 static struct bpt *at_breakpoint(unsigned long pc)
796 {
797 	int i;
798 	struct bpt *bp;
799 
800 	bp = bpts;
801 	for (i = 0; i < NBPTS; ++i, ++bp)
802 		if (bp->enabled && pc == bp->address)
803 			return bp;
804 	return NULL;
805 }
806 
807 static struct bpt *in_breakpoint_table(unsigned long nip, unsigned long *offp)
808 {
809 	unsigned long off;
810 
811 	off = nip - (unsigned long) bpts;
812 	if (off >= sizeof(bpts))
813 		return NULL;
814 	off %= sizeof(struct bpt);
815 	if (off != offsetof(struct bpt, instr[0])
816 	    && off != offsetof(struct bpt, instr[1]))
817 		return NULL;
818 	*offp = off - offsetof(struct bpt, instr[0]);
819 	return (struct bpt *) (nip - off);
820 }
821 
822 static struct bpt *new_breakpoint(unsigned long a)
823 {
824 	struct bpt *bp;
825 
826 	a &= ~3UL;
827 	bp = at_breakpoint(a);
828 	if (bp)
829 		return bp;
830 
831 	for (bp = bpts; bp < &bpts[NBPTS]; ++bp) {
832 		if (!bp->enabled && atomic_read(&bp->ref_count) == 0) {
833 			bp->address = a;
834 			bp->instr[1] = bpinstr;
835 			store_inst(&bp->instr[1]);
836 			return bp;
837 		}
838 	}
839 
840 	printf("Sorry, no free breakpoints.  Please clear one first.\n");
841 	return NULL;
842 }
843 
844 static void insert_bpts(void)
845 {
846 	int i;
847 	struct bpt *bp;
848 
849 	bp = bpts;
850 	for (i = 0; i < NBPTS; ++i, ++bp) {
851 		if ((bp->enabled & (BP_TRAP|BP_CIABR)) == 0)
852 			continue;
853 		if (mread(bp->address, &bp->instr[0], 4) != 4) {
854 			printf("Couldn't read instruction at %lx, "
855 			       "disabling breakpoint there\n", bp->address);
856 			bp->enabled = 0;
857 			continue;
858 		}
859 		if (IS_MTMSRD(bp->instr[0]) || IS_RFID(bp->instr[0])) {
860 			printf("Breakpoint at %lx is on an mtmsrd or rfid "
861 			       "instruction, disabling it\n", bp->address);
862 			bp->enabled = 0;
863 			continue;
864 		}
865 		store_inst(&bp->instr[0]);
866 		if (bp->enabled & BP_CIABR)
867 			continue;
868 		if (patch_instruction((unsigned int *)bp->address,
869 							bpinstr) != 0) {
870 			printf("Couldn't write instruction at %lx, "
871 			       "disabling breakpoint there\n", bp->address);
872 			bp->enabled &= ~BP_TRAP;
873 			continue;
874 		}
875 		store_inst((void *)bp->address);
876 	}
877 }
878 
879 static void insert_cpu_bpts(void)
880 {
881 	struct arch_hw_breakpoint brk;
882 
883 	if (dabr.enabled) {
884 		brk.address = dabr.address;
885 		brk.type = (dabr.enabled & HW_BRK_TYPE_DABR) | HW_BRK_TYPE_PRIV_ALL;
886 		brk.len = 8;
887 		__set_breakpoint(&brk);
888 	}
889 
890 	if (iabr)
891 		set_ciabr(iabr->address);
892 }
893 
894 static void remove_bpts(void)
895 {
896 	int i;
897 	struct bpt *bp;
898 	unsigned instr;
899 
900 	bp = bpts;
901 	for (i = 0; i < NBPTS; ++i, ++bp) {
902 		if ((bp->enabled & (BP_TRAP|BP_CIABR)) != BP_TRAP)
903 			continue;
904 		if (mread(bp->address, &instr, 4) == 4
905 		    && instr == bpinstr
906 		    && patch_instruction(
907 			(unsigned int *)bp->address, bp->instr[0]) != 0)
908 			printf("Couldn't remove breakpoint at %lx\n",
909 			       bp->address);
910 		else
911 			store_inst((void *)bp->address);
912 	}
913 }
914 
915 static void remove_cpu_bpts(void)
916 {
917 	hw_breakpoint_disable();
918 	write_ciabr(0);
919 }
920 
921 /* Based on uptime_proc_show(). */
922 static void
923 show_uptime(void)
924 {
925 	struct timespec64 uptime;
926 
927 	if (setjmp(bus_error_jmp) == 0) {
928 		catch_memory_errors = 1;
929 		sync();
930 
931 		ktime_get_coarse_boottime_ts64(&uptime);
932 		printf("Uptime: %lu.%.2lu seconds\n", (unsigned long)uptime.tv_sec,
933 			((unsigned long)uptime.tv_nsec / (NSEC_PER_SEC/100)));
934 
935 		sync();
936 		__delay(200);						\
937 	}
938 	catch_memory_errors = 0;
939 }
940 
941 static void set_lpp_cmd(void)
942 {
943 	unsigned long lpp;
944 
945 	if (!scanhex(&lpp)) {
946 		printf("Invalid number.\n");
947 		lpp = 0;
948 	}
949 	xmon_set_pagination_lpp(lpp);
950 }
951 /* Command interpreting routine */
952 static char *last_cmd;
953 
954 static int
955 cmds(struct pt_regs *excp)
956 {
957 	int cmd = 0;
958 
959 	last_cmd = NULL;
960 	xmon_regs = excp;
961 
962 	xmon_show_stack(excp->gpr[1], excp->link, excp->nip);
963 
964 	for(;;) {
965 #ifdef CONFIG_SMP
966 		printf("%x:", smp_processor_id());
967 #endif /* CONFIG_SMP */
968 		printf("mon> ");
969 		flush_input();
970 		termch = 0;
971 		cmd = skipbl();
972 		if( cmd == '\n' ) {
973 			if (last_cmd == NULL)
974 				continue;
975 			take_input(last_cmd);
976 			last_cmd = NULL;
977 			cmd = inchar();
978 		}
979 		switch (cmd) {
980 		case 'm':
981 			cmd = inchar();
982 			switch (cmd) {
983 			case 'm':
984 			case 's':
985 			case 'd':
986 				memops(cmd);
987 				break;
988 			case 'l':
989 				memlocate();
990 				break;
991 			case 'z':
992 				memzcan();
993 				break;
994 			case 'i':
995 				show_mem(0, NULL);
996 				break;
997 			default:
998 				termch = cmd;
999 				memex();
1000 			}
1001 			break;
1002 		case 'd':
1003 			dump();
1004 			break;
1005 		case 'l':
1006 			symbol_lookup();
1007 			break;
1008 		case 'r':
1009 			prregs(excp);	/* print regs */
1010 			break;
1011 		case 'e':
1012 			excprint(excp);
1013 			break;
1014 		case 'S':
1015 			super_regs();
1016 			break;
1017 		case 't':
1018 			backtrace(excp);
1019 			break;
1020 		case 'f':
1021 			cacheflush();
1022 			break;
1023 		case 's':
1024 			if (do_spu_cmd() == 0)
1025 				break;
1026 			if (do_step(excp))
1027 				return cmd;
1028 			break;
1029 		case 'x':
1030 		case 'X':
1031 			if (tracing_enabled)
1032 				tracing_on();
1033 			return cmd;
1034 		case EOF:
1035 			printf(" <no input ...>\n");
1036 			mdelay(2000);
1037 			return cmd;
1038 		case '?':
1039 			xmon_puts(help_string);
1040 			break;
1041 		case '#':
1042 			set_lpp_cmd();
1043 			break;
1044 		case 'b':
1045 			bpt_cmds();
1046 			break;
1047 		case 'C':
1048 			csum();
1049 			break;
1050 		case 'c':
1051 			if (cpu_cmd())
1052 				return 0;
1053 			break;
1054 		case 'z':
1055 			bootcmds();
1056 			break;
1057 		case 'p':
1058 			proccall();
1059 			break;
1060 		case 'P':
1061 			show_tasks();
1062 			break;
1063 #ifdef CONFIG_PPC_BOOK3S
1064 		case 'u':
1065 			dump_segments();
1066 			break;
1067 #elif defined(CONFIG_44x)
1068 		case 'u':
1069 			dump_tlb_44x();
1070 			break;
1071 #elif defined(CONFIG_PPC_BOOK3E)
1072 		case 'u':
1073 			dump_tlb_book3e();
1074 			break;
1075 #endif
1076 		case 'U':
1077 			show_uptime();
1078 			break;
1079 		default:
1080 			printf("Unrecognized command: ");
1081 			do {
1082 				if (' ' < cmd && cmd <= '~')
1083 					putchar(cmd);
1084 				else
1085 					printf("\\x%x", cmd);
1086 				cmd = inchar();
1087 			} while (cmd != '\n');
1088 			printf(" (type ? for help)\n");
1089 			break;
1090 		}
1091 	}
1092 }
1093 
1094 #ifdef CONFIG_BOOKE
1095 static int do_step(struct pt_regs *regs)
1096 {
1097 	regs->msr |= MSR_DE;
1098 	mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM);
1099 	return 1;
1100 }
1101 #else
1102 /*
1103  * Step a single instruction.
1104  * Some instructions we emulate, others we execute with MSR_SE set.
1105  */
1106 static int do_step(struct pt_regs *regs)
1107 {
1108 	unsigned int instr;
1109 	int stepped;
1110 
1111 	force_enable_xmon();
1112 	/* check we are in 64-bit kernel mode, translation enabled */
1113 	if ((regs->msr & (MSR_64BIT|MSR_PR|MSR_IR)) == (MSR_64BIT|MSR_IR)) {
1114 		if (mread(regs->nip, &instr, 4) == 4) {
1115 			stepped = emulate_step(regs, instr);
1116 			if (stepped < 0) {
1117 				printf("Couldn't single-step %s instruction\n",
1118 				       (IS_RFID(instr)? "rfid": "mtmsrd"));
1119 				return 0;
1120 			}
1121 			if (stepped > 0) {
1122 				regs->trap = 0xd00 | (regs->trap & 1);
1123 				printf("stepped to ");
1124 				xmon_print_symbol(regs->nip, " ", "\n");
1125 				ppc_inst_dump(regs->nip, 1, 0);
1126 				return 0;
1127 			}
1128 		}
1129 	}
1130 	regs->msr |= MSR_SE;
1131 	return 1;
1132 }
1133 #endif
1134 
1135 static void bootcmds(void)
1136 {
1137 	int cmd;
1138 
1139 	cmd = inchar();
1140 	if (cmd == 'r')
1141 		ppc_md.restart(NULL);
1142 	else if (cmd == 'h')
1143 		ppc_md.halt();
1144 	else if (cmd == 'p')
1145 		if (pm_power_off)
1146 			pm_power_off();
1147 }
1148 
1149 static int cpu_cmd(void)
1150 {
1151 #ifdef CONFIG_SMP
1152 	unsigned long cpu, first_cpu, last_cpu;
1153 	int timeout;
1154 
1155 	if (!scanhex(&cpu)) {
1156 		/* print cpus waiting or in xmon */
1157 		printf("cpus stopped:");
1158 		last_cpu = first_cpu = NR_CPUS;
1159 		for_each_possible_cpu(cpu) {
1160 			if (cpumask_test_cpu(cpu, &cpus_in_xmon)) {
1161 				if (cpu == last_cpu + 1) {
1162 					last_cpu = cpu;
1163 				} else {
1164 					if (last_cpu != first_cpu)
1165 						printf("-0x%lx", last_cpu);
1166 					last_cpu = first_cpu = cpu;
1167 					printf(" 0x%lx", cpu);
1168 				}
1169 			}
1170 		}
1171 		if (last_cpu != first_cpu)
1172 			printf("-0x%lx", last_cpu);
1173 		printf("\n");
1174 		return 0;
1175 	}
1176 	/* try to switch to cpu specified */
1177 	if (!cpumask_test_cpu(cpu, &cpus_in_xmon)) {
1178 		printf("cpu 0x%lx isn't in xmon\n", cpu);
1179 #ifdef CONFIG_PPC64
1180 		printf("backtrace of paca[0x%lx].saved_r1 (possibly stale):\n", cpu);
1181 		xmon_show_stack(paca_ptrs[cpu]->saved_r1, 0, 0);
1182 #endif
1183 		return 0;
1184 	}
1185 	xmon_taken = 0;
1186 	mb();
1187 	xmon_owner = cpu;
1188 	timeout = 10000000;
1189 	while (!xmon_taken) {
1190 		if (--timeout == 0) {
1191 			if (test_and_set_bit(0, &xmon_taken))
1192 				break;
1193 			/* take control back */
1194 			mb();
1195 			xmon_owner = smp_processor_id();
1196 			printf("cpu 0x%lx didn't take control\n", cpu);
1197 			return 0;
1198 		}
1199 		barrier();
1200 	}
1201 	return 1;
1202 #else
1203 	return 0;
1204 #endif /* CONFIG_SMP */
1205 }
1206 
1207 static unsigned short fcstab[256] = {
1208 	0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
1209 	0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
1210 	0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
1211 	0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
1212 	0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
1213 	0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
1214 	0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
1215 	0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
1216 	0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
1217 	0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
1218 	0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
1219 	0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
1220 	0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
1221 	0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
1222 	0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
1223 	0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
1224 	0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
1225 	0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
1226 	0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
1227 	0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
1228 	0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
1229 	0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
1230 	0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
1231 	0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
1232 	0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
1233 	0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
1234 	0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
1235 	0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
1236 	0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
1237 	0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
1238 	0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
1239 	0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
1240 };
1241 
1242 #define FCS(fcs, c)	(((fcs) >> 8) ^ fcstab[((fcs) ^ (c)) & 0xff])
1243 
1244 static void
1245 csum(void)
1246 {
1247 	unsigned int i;
1248 	unsigned short fcs;
1249 	unsigned char v;
1250 
1251 	if (!scanhex(&adrs))
1252 		return;
1253 	if (!scanhex(&ncsum))
1254 		return;
1255 	fcs = 0xffff;
1256 	for (i = 0; i < ncsum; ++i) {
1257 		if (mread(adrs+i, &v, 1) == 0) {
1258 			printf("csum stopped at "REG"\n", adrs+i);
1259 			break;
1260 		}
1261 		fcs = FCS(fcs, v);
1262 	}
1263 	printf("%x\n", fcs);
1264 }
1265 
1266 /*
1267  * Check if this is a suitable place to put a breakpoint.
1268  */
1269 static long check_bp_loc(unsigned long addr)
1270 {
1271 	unsigned int instr;
1272 
1273 	addr &= ~3;
1274 	if (!is_kernel_addr(addr)) {
1275 		printf("Breakpoints may only be placed at kernel addresses\n");
1276 		return 0;
1277 	}
1278 	if (!mread(addr, &instr, sizeof(instr))) {
1279 		printf("Can't read instruction at address %lx\n", addr);
1280 		return 0;
1281 	}
1282 	if (IS_MTMSRD(instr) || IS_RFID(instr)) {
1283 		printf("Breakpoints may not be placed on mtmsrd or rfid "
1284 		       "instructions\n");
1285 		return 0;
1286 	}
1287 	return 1;
1288 }
1289 
1290 static char *breakpoint_help_string =
1291     "Breakpoint command usage:\n"
1292     "b                show breakpoints\n"
1293     "b <addr> [cnt]   set breakpoint at given instr addr\n"
1294     "bc               clear all breakpoints\n"
1295     "bc <n/addr>      clear breakpoint number n or at addr\n"
1296     "bi <addr> [cnt]  set hardware instr breakpoint (POWER8 only)\n"
1297     "bd <addr> [cnt]  set hardware data breakpoint\n"
1298     "";
1299 
1300 static void
1301 bpt_cmds(void)
1302 {
1303 	int cmd;
1304 	unsigned long a;
1305 	int i;
1306 	struct bpt *bp;
1307 
1308 	cmd = inchar();
1309 	switch (cmd) {
1310 #ifndef CONFIG_PPC_8xx
1311 	static const char badaddr[] = "Only kernel addresses are permitted for breakpoints\n";
1312 	int mode;
1313 	case 'd':	/* bd - hardware data breakpoint */
1314 		if (!ppc_breakpoint_available()) {
1315 			printf("Hardware data breakpoint not supported on this cpu\n");
1316 			break;
1317 		}
1318 		mode = 7;
1319 		cmd = inchar();
1320 		if (cmd == 'r')
1321 			mode = 5;
1322 		else if (cmd == 'w')
1323 			mode = 6;
1324 		else
1325 			termch = cmd;
1326 		dabr.address = 0;
1327 		dabr.enabled = 0;
1328 		if (scanhex(&dabr.address)) {
1329 			if (!is_kernel_addr(dabr.address)) {
1330 				printf(badaddr);
1331 				break;
1332 			}
1333 			dabr.address &= ~HW_BRK_TYPE_DABR;
1334 			dabr.enabled = mode | BP_DABR;
1335 		}
1336 
1337 		force_enable_xmon();
1338 		break;
1339 
1340 	case 'i':	/* bi - hardware instr breakpoint */
1341 		if (!cpu_has_feature(CPU_FTR_ARCH_207S)) {
1342 			printf("Hardware instruction breakpoint "
1343 			       "not supported on this cpu\n");
1344 			break;
1345 		}
1346 		if (iabr) {
1347 			iabr->enabled &= ~BP_CIABR;
1348 			iabr = NULL;
1349 		}
1350 		if (!scanhex(&a))
1351 			break;
1352 		if (!check_bp_loc(a))
1353 			break;
1354 		bp = new_breakpoint(a);
1355 		if (bp != NULL) {
1356 			bp->enabled |= BP_CIABR;
1357 			iabr = bp;
1358 			force_enable_xmon();
1359 		}
1360 		break;
1361 #endif
1362 
1363 	case 'c':
1364 		if (!scanhex(&a)) {
1365 			/* clear all breakpoints */
1366 			for (i = 0; i < NBPTS; ++i)
1367 				bpts[i].enabled = 0;
1368 			iabr = NULL;
1369 			dabr.enabled = 0;
1370 			printf("All breakpoints cleared\n");
1371 			break;
1372 		}
1373 
1374 		if (a <= NBPTS && a >= 1) {
1375 			/* assume a breakpoint number */
1376 			bp = &bpts[a-1];	/* bp nums are 1 based */
1377 		} else {
1378 			/* assume a breakpoint address */
1379 			bp = at_breakpoint(a);
1380 			if (bp == NULL) {
1381 				printf("No breakpoint at %lx\n", a);
1382 				break;
1383 			}
1384 		}
1385 
1386 		printf("Cleared breakpoint %tx (", BP_NUM(bp));
1387 		xmon_print_symbol(bp->address, " ", ")\n");
1388 		bp->enabled = 0;
1389 		break;
1390 
1391 	default:
1392 		termch = cmd;
1393 		cmd = skipbl();
1394 		if (cmd == '?') {
1395 			printf(breakpoint_help_string);
1396 			break;
1397 		}
1398 		termch = cmd;
1399 		if (!scanhex(&a)) {
1400 			/* print all breakpoints */
1401 			printf("   type            address\n");
1402 			if (dabr.enabled) {
1403 				printf("   data   "REG"  [", dabr.address);
1404 				if (dabr.enabled & 1)
1405 					printf("r");
1406 				if (dabr.enabled & 2)
1407 					printf("w");
1408 				printf("]\n");
1409 			}
1410 			for (bp = bpts; bp < &bpts[NBPTS]; ++bp) {
1411 				if (!bp->enabled)
1412 					continue;
1413 				printf("%tx %s   ", BP_NUM(bp),
1414 				    (bp->enabled & BP_CIABR) ? "inst": "trap");
1415 				xmon_print_symbol(bp->address, "  ", "\n");
1416 			}
1417 			break;
1418 		}
1419 
1420 		if (!check_bp_loc(a))
1421 			break;
1422 		bp = new_breakpoint(a);
1423 		if (bp != NULL) {
1424 			bp->enabled |= BP_TRAP;
1425 			force_enable_xmon();
1426 		}
1427 		break;
1428 	}
1429 }
1430 
1431 /* Very cheap human name for vector lookup. */
1432 static
1433 const char *getvecname(unsigned long vec)
1434 {
1435 	char *ret;
1436 
1437 	switch (vec) {
1438 	case 0x100:	ret = "(System Reset)"; break;
1439 	case 0x200:	ret = "(Machine Check)"; break;
1440 	case 0x300:	ret = "(Data Access)"; break;
1441 	case 0x380:
1442 		if (radix_enabled())
1443 			ret = "(Data Access Out of Range)";
1444 		else
1445 			ret = "(Data SLB Access)";
1446 		break;
1447 	case 0x400:	ret = "(Instruction Access)"; break;
1448 	case 0x480:
1449 		if (radix_enabled())
1450 			ret = "(Instruction Access Out of Range)";
1451 		else
1452 			ret = "(Instruction SLB Access)";
1453 		break;
1454 	case 0x500:	ret = "(Hardware Interrupt)"; break;
1455 	case 0x600:	ret = "(Alignment)"; break;
1456 	case 0x700:	ret = "(Program Check)"; break;
1457 	case 0x800:	ret = "(FPU Unavailable)"; break;
1458 	case 0x900:	ret = "(Decrementer)"; break;
1459 	case 0x980:	ret = "(Hypervisor Decrementer)"; break;
1460 	case 0xa00:	ret = "(Doorbell)"; break;
1461 	case 0xc00:	ret = "(System Call)"; break;
1462 	case 0xd00:	ret = "(Single Step)"; break;
1463 	case 0xe40:	ret = "(Emulation Assist)"; break;
1464 	case 0xe60:	ret = "(HMI)"; break;
1465 	case 0xe80:	ret = "(Hypervisor Doorbell)"; break;
1466 	case 0xf00:	ret = "(Performance Monitor)"; break;
1467 	case 0xf20:	ret = "(Altivec Unavailable)"; break;
1468 	case 0x1300:	ret = "(Instruction Breakpoint)"; break;
1469 	case 0x1500:	ret = "(Denormalisation)"; break;
1470 	case 0x1700:	ret = "(Altivec Assist)"; break;
1471 	default: ret = "";
1472 	}
1473 	return ret;
1474 }
1475 
1476 static void get_function_bounds(unsigned long pc, unsigned long *startp,
1477 				unsigned long *endp)
1478 {
1479 	unsigned long size, offset;
1480 	const char *name;
1481 
1482 	*startp = *endp = 0;
1483 	if (pc == 0)
1484 		return;
1485 	if (setjmp(bus_error_jmp) == 0) {
1486 		catch_memory_errors = 1;
1487 		sync();
1488 		name = kallsyms_lookup(pc, &size, &offset, NULL, tmpstr);
1489 		if (name != NULL) {
1490 			*startp = pc - offset;
1491 			*endp = pc - offset + size;
1492 		}
1493 		sync();
1494 	}
1495 	catch_memory_errors = 0;
1496 }
1497 
1498 #define LRSAVE_OFFSET		(STACK_FRAME_LR_SAVE * sizeof(unsigned long))
1499 #define MARKER_OFFSET		(STACK_FRAME_MARKER * sizeof(unsigned long))
1500 
1501 static void xmon_show_stack(unsigned long sp, unsigned long lr,
1502 			    unsigned long pc)
1503 {
1504 	int max_to_print = 64;
1505 	unsigned long ip;
1506 	unsigned long newsp;
1507 	unsigned long marker;
1508 	struct pt_regs regs;
1509 
1510 	while (max_to_print--) {
1511 		if (!is_kernel_addr(sp)) {
1512 			if (sp != 0)
1513 				printf("SP (%lx) is in userspace\n", sp);
1514 			break;
1515 		}
1516 
1517 		if (!mread(sp + LRSAVE_OFFSET, &ip, sizeof(unsigned long))
1518 		    || !mread(sp, &newsp, sizeof(unsigned long))) {
1519 			printf("Couldn't read stack frame at %lx\n", sp);
1520 			break;
1521 		}
1522 
1523 		/*
1524 		 * For the first stack frame, try to work out if
1525 		 * LR and/or the saved LR value in the bottommost
1526 		 * stack frame are valid.
1527 		 */
1528 		if ((pc | lr) != 0) {
1529 			unsigned long fnstart, fnend;
1530 			unsigned long nextip;
1531 			int printip = 1;
1532 
1533 			get_function_bounds(pc, &fnstart, &fnend);
1534 			nextip = 0;
1535 			if (newsp > sp)
1536 				mread(newsp + LRSAVE_OFFSET, &nextip,
1537 				      sizeof(unsigned long));
1538 			if (lr == ip) {
1539 				if (!is_kernel_addr(lr)
1540 				    || (fnstart <= lr && lr < fnend))
1541 					printip = 0;
1542 			} else if (lr == nextip) {
1543 				printip = 0;
1544 			} else if (is_kernel_addr(lr)
1545 				   && !(fnstart <= lr && lr < fnend)) {
1546 				printf("[link register   ] ");
1547 				xmon_print_symbol(lr, " ", "\n");
1548 			}
1549 			if (printip) {
1550 				printf("["REG"] ", sp);
1551 				xmon_print_symbol(ip, " ", " (unreliable)\n");
1552 			}
1553 			pc = lr = 0;
1554 
1555 		} else {
1556 			printf("["REG"] ", sp);
1557 			xmon_print_symbol(ip, " ", "\n");
1558 		}
1559 
1560 		/* Look for "regshere" marker to see if this is
1561 		   an exception frame. */
1562 		if (mread(sp + MARKER_OFFSET, &marker, sizeof(unsigned long))
1563 		    && marker == STACK_FRAME_REGS_MARKER) {
1564 			if (mread(sp + STACK_FRAME_OVERHEAD, &regs, sizeof(regs))
1565 			    != sizeof(regs)) {
1566 				printf("Couldn't read registers at %lx\n",
1567 				       sp + STACK_FRAME_OVERHEAD);
1568 				break;
1569 			}
1570 			printf("--- Exception: %lx %s at ", regs.trap,
1571 			       getvecname(TRAP(&regs)));
1572 			pc = regs.nip;
1573 			lr = regs.link;
1574 			xmon_print_symbol(pc, " ", "\n");
1575 		}
1576 
1577 		if (newsp == 0)
1578 			break;
1579 
1580 		sp = newsp;
1581 	}
1582 }
1583 
1584 static void backtrace(struct pt_regs *excp)
1585 {
1586 	unsigned long sp;
1587 
1588 	if (scanhex(&sp))
1589 		xmon_show_stack(sp, 0, 0);
1590 	else
1591 		xmon_show_stack(excp->gpr[1], excp->link, excp->nip);
1592 	scannl();
1593 }
1594 
1595 static void print_bug_trap(struct pt_regs *regs)
1596 {
1597 #ifdef CONFIG_BUG
1598 	const struct bug_entry *bug;
1599 	unsigned long addr;
1600 
1601 	if (regs->msr & MSR_PR)
1602 		return;		/* not in kernel */
1603 	addr = regs->nip;	/* address of trap instruction */
1604 	if (!is_kernel_addr(addr))
1605 		return;
1606 	bug = find_bug(regs->nip);
1607 	if (bug == NULL)
1608 		return;
1609 	if (is_warning_bug(bug))
1610 		return;
1611 
1612 #ifdef CONFIG_DEBUG_BUGVERBOSE
1613 	printf("kernel BUG at %s:%u!\n",
1614 	       bug->file, bug->line);
1615 #else
1616 	printf("kernel BUG at %px!\n", (void *)bug->bug_addr);
1617 #endif
1618 #endif /* CONFIG_BUG */
1619 }
1620 
1621 static void excprint(struct pt_regs *fp)
1622 {
1623 	unsigned long trap;
1624 
1625 #ifdef CONFIG_SMP
1626 	printf("cpu 0x%x: ", smp_processor_id());
1627 #endif /* CONFIG_SMP */
1628 
1629 	trap = TRAP(fp);
1630 	printf("Vector: %lx %s at [%px]\n", fp->trap, getvecname(trap), fp);
1631 	printf("    pc: ");
1632 	xmon_print_symbol(fp->nip, ": ", "\n");
1633 
1634 	printf("    lr: ");
1635 	xmon_print_symbol(fp->link, ": ", "\n");
1636 
1637 	printf("    sp: %lx\n", fp->gpr[1]);
1638 	printf("   msr: %lx\n", fp->msr);
1639 
1640 	if (trap == 0x300 || trap == 0x380 || trap == 0x600 || trap == 0x200) {
1641 		printf("   dar: %lx\n", fp->dar);
1642 		if (trap != 0x380)
1643 			printf(" dsisr: %lx\n", fp->dsisr);
1644 	}
1645 
1646 	printf("  current = 0x%px\n", current);
1647 #ifdef CONFIG_PPC64
1648 	printf("  paca    = 0x%px\t irqmask: 0x%02x\t irq_happened: 0x%02x\n",
1649 	       local_paca, local_paca->irq_soft_mask, local_paca->irq_happened);
1650 #endif
1651 	if (current) {
1652 		printf("    pid   = %d, comm = %s\n",
1653 		       current->pid, current->comm);
1654 	}
1655 
1656 	if (trap == 0x700)
1657 		print_bug_trap(fp);
1658 
1659 	printf(linux_banner);
1660 }
1661 
1662 static void prregs(struct pt_regs *fp)
1663 {
1664 	int n, trap;
1665 	unsigned long base;
1666 	struct pt_regs regs;
1667 
1668 	if (scanhex(&base)) {
1669 		if (setjmp(bus_error_jmp) == 0) {
1670 			catch_memory_errors = 1;
1671 			sync();
1672 			regs = *(struct pt_regs *)base;
1673 			sync();
1674 			__delay(200);
1675 		} else {
1676 			catch_memory_errors = 0;
1677 			printf("*** Error reading registers from "REG"\n",
1678 			       base);
1679 			return;
1680 		}
1681 		catch_memory_errors = 0;
1682 		fp = &regs;
1683 	}
1684 
1685 #ifdef CONFIG_PPC64
1686 	if (FULL_REGS(fp)) {
1687 		for (n = 0; n < 16; ++n)
1688 			printf("R%.2d = "REG"   R%.2d = "REG"\n",
1689 			       n, fp->gpr[n], n+16, fp->gpr[n+16]);
1690 	} else {
1691 		for (n = 0; n < 7; ++n)
1692 			printf("R%.2d = "REG"   R%.2d = "REG"\n",
1693 			       n, fp->gpr[n], n+7, fp->gpr[n+7]);
1694 	}
1695 #else
1696 	for (n = 0; n < 32; ++n) {
1697 		printf("R%.2d = %.8lx%s", n, fp->gpr[n],
1698 		       (n & 3) == 3? "\n": "   ");
1699 		if (n == 12 && !FULL_REGS(fp)) {
1700 			printf("\n");
1701 			break;
1702 		}
1703 	}
1704 #endif
1705 	printf("pc  = ");
1706 	xmon_print_symbol(fp->nip, " ", "\n");
1707 	if (TRAP(fp) != 0xc00 && cpu_has_feature(CPU_FTR_CFAR)) {
1708 		printf("cfar= ");
1709 		xmon_print_symbol(fp->orig_gpr3, " ", "\n");
1710 	}
1711 	printf("lr  = ");
1712 	xmon_print_symbol(fp->link, " ", "\n");
1713 	printf("msr = "REG"   cr  = %.8lx\n", fp->msr, fp->ccr);
1714 	printf("ctr = "REG"   xer = "REG"   trap = %4lx\n",
1715 	       fp->ctr, fp->xer, fp->trap);
1716 	trap = TRAP(fp);
1717 	if (trap == 0x300 || trap == 0x380 || trap == 0x600)
1718 		printf("dar = "REG"   dsisr = %.8lx\n", fp->dar, fp->dsisr);
1719 }
1720 
1721 static void cacheflush(void)
1722 {
1723 	int cmd;
1724 	unsigned long nflush;
1725 
1726 	cmd = inchar();
1727 	if (cmd != 'i')
1728 		termch = cmd;
1729 	scanhex((void *)&adrs);
1730 	if (termch != '\n')
1731 		termch = 0;
1732 	nflush = 1;
1733 	scanhex(&nflush);
1734 	nflush = (nflush + L1_CACHE_BYTES - 1) / L1_CACHE_BYTES;
1735 	if (setjmp(bus_error_jmp) == 0) {
1736 		catch_memory_errors = 1;
1737 		sync();
1738 
1739 		if (cmd != 'i') {
1740 			for (; nflush > 0; --nflush, adrs += L1_CACHE_BYTES)
1741 				cflush((void *) adrs);
1742 		} else {
1743 			for (; nflush > 0; --nflush, adrs += L1_CACHE_BYTES)
1744 				cinval((void *) adrs);
1745 		}
1746 		sync();
1747 		/* wait a little while to see if we get a machine check */
1748 		__delay(200);
1749 	}
1750 	catch_memory_errors = 0;
1751 }
1752 
1753 extern unsigned long xmon_mfspr(int spr, unsigned long default_value);
1754 extern void xmon_mtspr(int spr, unsigned long value);
1755 
1756 static int
1757 read_spr(int n, unsigned long *vp)
1758 {
1759 	unsigned long ret = -1UL;
1760 	int ok = 0;
1761 
1762 	if (setjmp(bus_error_jmp) == 0) {
1763 		catch_spr_faults = 1;
1764 		sync();
1765 
1766 		ret = xmon_mfspr(n, *vp);
1767 
1768 		sync();
1769 		*vp = ret;
1770 		ok = 1;
1771 	}
1772 	catch_spr_faults = 0;
1773 
1774 	return ok;
1775 }
1776 
1777 static void
1778 write_spr(int n, unsigned long val)
1779 {
1780 	if (setjmp(bus_error_jmp) == 0) {
1781 		catch_spr_faults = 1;
1782 		sync();
1783 
1784 		xmon_mtspr(n, val);
1785 
1786 		sync();
1787 	} else {
1788 		printf("SPR 0x%03x (%4d) Faulted during write\n", n, n);
1789 	}
1790 	catch_spr_faults = 0;
1791 }
1792 
1793 static void dump_206_sprs(void)
1794 {
1795 #ifdef CONFIG_PPC64
1796 	if (!cpu_has_feature(CPU_FTR_ARCH_206))
1797 		return;
1798 
1799 	/* Actually some of these pre-date 2.06, but whatevs */
1800 
1801 	printf("srr0   = %.16lx  srr1  = %.16lx dsisr  = %.8lx\n",
1802 		mfspr(SPRN_SRR0), mfspr(SPRN_SRR1), mfspr(SPRN_DSISR));
1803 	printf("dscr   = %.16lx  ppr   = %.16lx pir    = %.8lx\n",
1804 		mfspr(SPRN_DSCR), mfspr(SPRN_PPR), mfspr(SPRN_PIR));
1805 	printf("amr    = %.16lx  uamor = %.16lx\n",
1806 		mfspr(SPRN_AMR), mfspr(SPRN_UAMOR));
1807 
1808 	if (!(mfmsr() & MSR_HV))
1809 		return;
1810 
1811 	printf("sdr1   = %.16lx  hdar  = %.16lx hdsisr = %.8lx\n",
1812 		mfspr(SPRN_SDR1), mfspr(SPRN_HDAR), mfspr(SPRN_HDSISR));
1813 	printf("hsrr0  = %.16lx hsrr1  = %.16lx hdec   = %.16lx\n",
1814 		mfspr(SPRN_HSRR0), mfspr(SPRN_HSRR1), mfspr(SPRN_HDEC));
1815 	printf("lpcr   = %.16lx  pcr   = %.16lx lpidr  = %.8lx\n",
1816 		mfspr(SPRN_LPCR), mfspr(SPRN_PCR), mfspr(SPRN_LPID));
1817 	printf("hsprg0 = %.16lx hsprg1 = %.16lx amor   = %.16lx\n",
1818 		mfspr(SPRN_HSPRG0), mfspr(SPRN_HSPRG1), mfspr(SPRN_AMOR));
1819 	printf("dabr   = %.16lx dabrx  = %.16lx\n",
1820 		mfspr(SPRN_DABR), mfspr(SPRN_DABRX));
1821 #endif
1822 }
1823 
1824 static void dump_207_sprs(void)
1825 {
1826 #ifdef CONFIG_PPC64
1827 	unsigned long msr;
1828 
1829 	if (!cpu_has_feature(CPU_FTR_ARCH_207S))
1830 		return;
1831 
1832 	printf("dpdes  = %.16lx  tir   = %.16lx cir    = %.8lx\n",
1833 		mfspr(SPRN_DPDES), mfspr(SPRN_TIR), mfspr(SPRN_CIR));
1834 
1835 	printf("fscr   = %.16lx  tar   = %.16lx pspb   = %.8lx\n",
1836 		mfspr(SPRN_FSCR), mfspr(SPRN_TAR), mfspr(SPRN_PSPB));
1837 
1838 	msr = mfmsr();
1839 	if (msr & MSR_TM) {
1840 		/* Only if TM has been enabled in the kernel */
1841 		printf("tfhar  = %.16lx  tfiar = %.16lx texasr = %.16lx\n",
1842 			mfspr(SPRN_TFHAR), mfspr(SPRN_TFIAR),
1843 			mfspr(SPRN_TEXASR));
1844 	}
1845 
1846 	printf("mmcr0  = %.16lx  mmcr1 = %.16lx mmcr2  = %.16lx\n",
1847 		mfspr(SPRN_MMCR0), mfspr(SPRN_MMCR1), mfspr(SPRN_MMCR2));
1848 	printf("pmc1   = %.8lx pmc2 = %.8lx  pmc3 = %.8lx  pmc4   = %.8lx\n",
1849 		mfspr(SPRN_PMC1), mfspr(SPRN_PMC2),
1850 		mfspr(SPRN_PMC3), mfspr(SPRN_PMC4));
1851 	printf("mmcra  = %.16lx   siar = %.16lx pmc5   = %.8lx\n",
1852 		mfspr(SPRN_MMCRA), mfspr(SPRN_SIAR), mfspr(SPRN_PMC5));
1853 	printf("sdar   = %.16lx   sier = %.16lx pmc6   = %.8lx\n",
1854 		mfspr(SPRN_SDAR), mfspr(SPRN_SIER), mfspr(SPRN_PMC6));
1855 	printf("ebbhr  = %.16lx  ebbrr = %.16lx bescr  = %.16lx\n",
1856 		mfspr(SPRN_EBBHR), mfspr(SPRN_EBBRR), mfspr(SPRN_BESCR));
1857 	printf("iamr   = %.16lx\n", mfspr(SPRN_IAMR));
1858 
1859 	if (!(msr & MSR_HV))
1860 		return;
1861 
1862 	printf("hfscr  = %.16lx  dhdes = %.16lx rpr    = %.16lx\n",
1863 		mfspr(SPRN_HFSCR), mfspr(SPRN_DHDES), mfspr(SPRN_RPR));
1864 	printf("dawr   = %.16lx  dawrx = %.16lx ciabr  = %.16lx\n",
1865 		mfspr(SPRN_DAWR), mfspr(SPRN_DAWRX), mfspr(SPRN_CIABR));
1866 #endif
1867 }
1868 
1869 static void dump_300_sprs(void)
1870 {
1871 #ifdef CONFIG_PPC64
1872 	bool hv = mfmsr() & MSR_HV;
1873 
1874 	if (!cpu_has_feature(CPU_FTR_ARCH_300))
1875 		return;
1876 
1877 	printf("pidr   = %.16lx  tidr  = %.16lx\n",
1878 		mfspr(SPRN_PID), mfspr(SPRN_TIDR));
1879 	printf("asdr   = %.16lx  psscr = %.16lx\n",
1880 		mfspr(SPRN_ASDR), hv ? mfspr(SPRN_PSSCR)
1881 					: mfspr(SPRN_PSSCR_PR));
1882 
1883 	if (!hv)
1884 		return;
1885 
1886 	printf("ptcr   = %.16lx\n",
1887 		mfspr(SPRN_PTCR));
1888 #endif
1889 }
1890 
1891 static void dump_one_spr(int spr, bool show_unimplemented)
1892 {
1893 	unsigned long val;
1894 
1895 	val = 0xdeadbeef;
1896 	if (!read_spr(spr, &val)) {
1897 		printf("SPR 0x%03x (%4d) Faulted during read\n", spr, spr);
1898 		return;
1899 	}
1900 
1901 	if (val == 0xdeadbeef) {
1902 		/* Looks like read was a nop, confirm */
1903 		val = 0x0badcafe;
1904 		if (!read_spr(spr, &val)) {
1905 			printf("SPR 0x%03x (%4d) Faulted during read\n", spr, spr);
1906 			return;
1907 		}
1908 
1909 		if (val == 0x0badcafe) {
1910 			if (show_unimplemented)
1911 				printf("SPR 0x%03x (%4d) Unimplemented\n", spr, spr);
1912 			return;
1913 		}
1914 	}
1915 
1916 	printf("SPR 0x%03x (%4d) = 0x%lx\n", spr, spr, val);
1917 }
1918 
1919 static void super_regs(void)
1920 {
1921 	static unsigned long regno;
1922 	int cmd;
1923 	int spr;
1924 
1925 	cmd = skipbl();
1926 
1927 	switch (cmd) {
1928 	case '\n': {
1929 		unsigned long sp, toc;
1930 		asm("mr %0,1" : "=r" (sp) :);
1931 		asm("mr %0,2" : "=r" (toc) :);
1932 
1933 		printf("msr    = "REG"  sprg0 = "REG"\n",
1934 		       mfmsr(), mfspr(SPRN_SPRG0));
1935 		printf("pvr    = "REG"  sprg1 = "REG"\n",
1936 		       mfspr(SPRN_PVR), mfspr(SPRN_SPRG1));
1937 		printf("dec    = "REG"  sprg2 = "REG"\n",
1938 		       mfspr(SPRN_DEC), mfspr(SPRN_SPRG2));
1939 		printf("sp     = "REG"  sprg3 = "REG"\n", sp, mfspr(SPRN_SPRG3));
1940 		printf("toc    = "REG"  dar   = "REG"\n", toc, mfspr(SPRN_DAR));
1941 
1942 		dump_206_sprs();
1943 		dump_207_sprs();
1944 		dump_300_sprs();
1945 
1946 		return;
1947 	}
1948 	case 'w': {
1949 		unsigned long val;
1950 		scanhex(&regno);
1951 		val = 0;
1952 		read_spr(regno, &val);
1953 		scanhex(&val);
1954 		write_spr(regno, val);
1955 		dump_one_spr(regno, true);
1956 		break;
1957 	}
1958 	case 'r':
1959 		scanhex(&regno);
1960 		dump_one_spr(regno, true);
1961 		break;
1962 	case 'a':
1963 		/* dump ALL SPRs */
1964 		for (spr = 1; spr < 1024; ++spr)
1965 			dump_one_spr(spr, false);
1966 		break;
1967 	}
1968 
1969 	scannl();
1970 }
1971 
1972 /*
1973  * Stuff for reading and writing memory safely
1974  */
1975 static int
1976 mread(unsigned long adrs, void *buf, int size)
1977 {
1978 	volatile int n;
1979 	char *p, *q;
1980 
1981 	n = 0;
1982 	if (setjmp(bus_error_jmp) == 0) {
1983 		catch_memory_errors = 1;
1984 		sync();
1985 		p = (char *)adrs;
1986 		q = (char *)buf;
1987 		switch (size) {
1988 		case 2:
1989 			*(u16 *)q = *(u16 *)p;
1990 			break;
1991 		case 4:
1992 			*(u32 *)q = *(u32 *)p;
1993 			break;
1994 		case 8:
1995 			*(u64 *)q = *(u64 *)p;
1996 			break;
1997 		default:
1998 			for( ; n < size; ++n) {
1999 				*q++ = *p++;
2000 				sync();
2001 			}
2002 		}
2003 		sync();
2004 		/* wait a little while to see if we get a machine check */
2005 		__delay(200);
2006 		n = size;
2007 	}
2008 	catch_memory_errors = 0;
2009 	return n;
2010 }
2011 
2012 static int
2013 mwrite(unsigned long adrs, void *buf, int size)
2014 {
2015 	volatile int n;
2016 	char *p, *q;
2017 
2018 	n = 0;
2019 	if (setjmp(bus_error_jmp) == 0) {
2020 		catch_memory_errors = 1;
2021 		sync();
2022 		p = (char *) adrs;
2023 		q = (char *) buf;
2024 		switch (size) {
2025 		case 2:
2026 			*(u16 *)p = *(u16 *)q;
2027 			break;
2028 		case 4:
2029 			*(u32 *)p = *(u32 *)q;
2030 			break;
2031 		case 8:
2032 			*(u64 *)p = *(u64 *)q;
2033 			break;
2034 		default:
2035 			for ( ; n < size; ++n) {
2036 				*p++ = *q++;
2037 				sync();
2038 			}
2039 		}
2040 		sync();
2041 		/* wait a little while to see if we get a machine check */
2042 		__delay(200);
2043 		n = size;
2044 	} else {
2045 		printf("*** Error writing address "REG"\n", adrs + n);
2046 	}
2047 	catch_memory_errors = 0;
2048 	return n;
2049 }
2050 
2051 static int fault_type;
2052 static int fault_except;
2053 static char *fault_chars[] = { "--", "**", "##" };
2054 
2055 static int handle_fault(struct pt_regs *regs)
2056 {
2057 	fault_except = TRAP(regs);
2058 	switch (TRAP(regs)) {
2059 	case 0x200:
2060 		fault_type = 0;
2061 		break;
2062 	case 0x300:
2063 	case 0x380:
2064 		fault_type = 1;
2065 		break;
2066 	default:
2067 		fault_type = 2;
2068 	}
2069 
2070 	longjmp(bus_error_jmp, 1);
2071 
2072 	return 0;
2073 }
2074 
2075 #define SWAP(a, b, t)	((t) = (a), (a) = (b), (b) = (t))
2076 
2077 static void
2078 byterev(unsigned char *val, int size)
2079 {
2080 	int t;
2081 
2082 	switch (size) {
2083 	case 2:
2084 		SWAP(val[0], val[1], t);
2085 		break;
2086 	case 4:
2087 		SWAP(val[0], val[3], t);
2088 		SWAP(val[1], val[2], t);
2089 		break;
2090 	case 8: /* is there really any use for this? */
2091 		SWAP(val[0], val[7], t);
2092 		SWAP(val[1], val[6], t);
2093 		SWAP(val[2], val[5], t);
2094 		SWAP(val[3], val[4], t);
2095 		break;
2096 	}
2097 }
2098 
2099 static int brev;
2100 static int mnoread;
2101 
2102 static char *memex_help_string =
2103     "Memory examine command usage:\n"
2104     "m [addr] [flags] examine/change memory\n"
2105     "  addr is optional.  will start where left off.\n"
2106     "  flags may include chars from this set:\n"
2107     "    b   modify by bytes (default)\n"
2108     "    w   modify by words (2 byte)\n"
2109     "    l   modify by longs (4 byte)\n"
2110     "    d   modify by doubleword (8 byte)\n"
2111     "    r   toggle reverse byte order mode\n"
2112     "    n   do not read memory (for i/o spaces)\n"
2113     "    .   ok to read (default)\n"
2114     "NOTE: flags are saved as defaults\n"
2115     "";
2116 
2117 static char *memex_subcmd_help_string =
2118     "Memory examine subcommands:\n"
2119     "  hexval   write this val to current location\n"
2120     "  'string' write chars from string to this location\n"
2121     "  '        increment address\n"
2122     "  ^        decrement address\n"
2123     "  /        increment addr by 0x10.  //=0x100, ///=0x1000, etc\n"
2124     "  \\        decrement addr by 0x10.  \\\\=0x100, \\\\\\=0x1000, etc\n"
2125     "  `        clear no-read flag\n"
2126     "  ;        stay at this addr\n"
2127     "  v        change to byte mode\n"
2128     "  w        change to word (2 byte) mode\n"
2129     "  l        change to long (4 byte) mode\n"
2130     "  u        change to doubleword (8 byte) mode\n"
2131     "  m addr   change current addr\n"
2132     "  n        toggle no-read flag\n"
2133     "  r        toggle byte reverse flag\n"
2134     "  < count  back up count bytes\n"
2135     "  > count  skip forward count bytes\n"
2136     "  x        exit this mode\n"
2137     "";
2138 
2139 static void
2140 memex(void)
2141 {
2142 	int cmd, inc, i, nslash;
2143 	unsigned long n;
2144 	unsigned char val[16];
2145 
2146 	scanhex((void *)&adrs);
2147 	cmd = skipbl();
2148 	if (cmd == '?') {
2149 		printf(memex_help_string);
2150 		return;
2151 	} else {
2152 		termch = cmd;
2153 	}
2154 	last_cmd = "m\n";
2155 	while ((cmd = skipbl()) != '\n') {
2156 		switch( cmd ){
2157 		case 'b':	size = 1;	break;
2158 		case 'w':	size = 2;	break;
2159 		case 'l':	size = 4;	break;
2160 		case 'd':	size = 8;	break;
2161 		case 'r': 	brev = !brev;	break;
2162 		case 'n':	mnoread = 1;	break;
2163 		case '.':	mnoread = 0;	break;
2164 		}
2165 	}
2166 	if( size <= 0 )
2167 		size = 1;
2168 	else if( size > 8 )
2169 		size = 8;
2170 	for(;;){
2171 		if (!mnoread)
2172 			n = mread(adrs, val, size);
2173 		printf(REG"%c", adrs, brev? 'r': ' ');
2174 		if (!mnoread) {
2175 			if (brev)
2176 				byterev(val, size);
2177 			putchar(' ');
2178 			for (i = 0; i < n; ++i)
2179 				printf("%.2x", val[i]);
2180 			for (; i < size; ++i)
2181 				printf("%s", fault_chars[fault_type]);
2182 		}
2183 		putchar(' ');
2184 		inc = size;
2185 		nslash = 0;
2186 		for(;;){
2187 			if( scanhex(&n) ){
2188 				for (i = 0; i < size; ++i)
2189 					val[i] = n >> (i * 8);
2190 				if (!brev)
2191 					byterev(val, size);
2192 				mwrite(adrs, val, size);
2193 				inc = size;
2194 			}
2195 			cmd = skipbl();
2196 			if (cmd == '\n')
2197 				break;
2198 			inc = 0;
2199 			switch (cmd) {
2200 			case '\'':
2201 				for(;;){
2202 					n = inchar();
2203 					if( n == '\\' )
2204 						n = bsesc();
2205 					else if( n == '\'' )
2206 						break;
2207 					for (i = 0; i < size; ++i)
2208 						val[i] = n >> (i * 8);
2209 					if (!brev)
2210 						byterev(val, size);
2211 					mwrite(adrs, val, size);
2212 					adrs += size;
2213 				}
2214 				adrs -= size;
2215 				inc = size;
2216 				break;
2217 			case ',':
2218 				adrs += size;
2219 				break;
2220 			case '.':
2221 				mnoread = 0;
2222 				break;
2223 			case ';':
2224 				break;
2225 			case 'x':
2226 			case EOF:
2227 				scannl();
2228 				return;
2229 			case 'b':
2230 			case 'v':
2231 				size = 1;
2232 				break;
2233 			case 'w':
2234 				size = 2;
2235 				break;
2236 			case 'l':
2237 				size = 4;
2238 				break;
2239 			case 'u':
2240 				size = 8;
2241 				break;
2242 			case '^':
2243 				adrs -= size;
2244 				break;
2245 			case '/':
2246 				if (nslash > 0)
2247 					adrs -= 1 << nslash;
2248 				else
2249 					nslash = 0;
2250 				nslash += 4;
2251 				adrs += 1 << nslash;
2252 				break;
2253 			case '\\':
2254 				if (nslash < 0)
2255 					adrs += 1 << -nslash;
2256 				else
2257 					nslash = 0;
2258 				nslash -= 4;
2259 				adrs -= 1 << -nslash;
2260 				break;
2261 			case 'm':
2262 				scanhex((void *)&adrs);
2263 				break;
2264 			case 'n':
2265 				mnoread = 1;
2266 				break;
2267 			case 'r':
2268 				brev = !brev;
2269 				break;
2270 			case '<':
2271 				n = size;
2272 				scanhex(&n);
2273 				adrs -= n;
2274 				break;
2275 			case '>':
2276 				n = size;
2277 				scanhex(&n);
2278 				adrs += n;
2279 				break;
2280 			case '?':
2281 				printf(memex_subcmd_help_string);
2282 				break;
2283 			}
2284 		}
2285 		adrs += inc;
2286 	}
2287 }
2288 
2289 static int
2290 bsesc(void)
2291 {
2292 	int c;
2293 
2294 	c = inchar();
2295 	switch( c ){
2296 	case 'n':	c = '\n';	break;
2297 	case 'r':	c = '\r';	break;
2298 	case 'b':	c = '\b';	break;
2299 	case 't':	c = '\t';	break;
2300 	}
2301 	return c;
2302 }
2303 
2304 static void xmon_rawdump (unsigned long adrs, long ndump)
2305 {
2306 	long n, m, r, nr;
2307 	unsigned char temp[16];
2308 
2309 	for (n = ndump; n > 0;) {
2310 		r = n < 16? n: 16;
2311 		nr = mread(adrs, temp, r);
2312 		adrs += nr;
2313 		for (m = 0; m < r; ++m) {
2314 			if (m < nr)
2315 				printf("%.2x", temp[m]);
2316 			else
2317 				printf("%s", fault_chars[fault_type]);
2318 		}
2319 		n -= r;
2320 		if (nr < r)
2321 			break;
2322 	}
2323 	printf("\n");
2324 }
2325 
2326 static void dump_tracing(void)
2327 {
2328 	int c;
2329 
2330 	c = inchar();
2331 	if (c == 'c')
2332 		ftrace_dump(DUMP_ORIG);
2333 	else
2334 		ftrace_dump(DUMP_ALL);
2335 }
2336 
2337 #ifdef CONFIG_PPC64
2338 static void dump_one_paca(int cpu)
2339 {
2340 	struct paca_struct *p;
2341 #ifdef CONFIG_PPC_BOOK3S_64
2342 	int i = 0;
2343 #endif
2344 
2345 	if (setjmp(bus_error_jmp) != 0) {
2346 		printf("*** Error dumping paca for cpu 0x%x!\n", cpu);
2347 		return;
2348 	}
2349 
2350 	catch_memory_errors = 1;
2351 	sync();
2352 
2353 	p = paca_ptrs[cpu];
2354 
2355 	printf("paca for cpu 0x%x @ %px:\n", cpu, p);
2356 
2357 	printf(" %-*s = %s\n", 25, "possible", cpu_possible(cpu) ? "yes" : "no");
2358 	printf(" %-*s = %s\n", 25, "present", cpu_present(cpu) ? "yes" : "no");
2359 	printf(" %-*s = %s\n", 25, "online", cpu_online(cpu) ? "yes" : "no");
2360 
2361 #define DUMP(paca, name, format)				\
2362 	printf(" %-*s = "format"\t(0x%lx)\n", 25, #name, 18, paca->name, \
2363 		offsetof(struct paca_struct, name));
2364 
2365 	DUMP(p, lock_token, "%#-*x");
2366 	DUMP(p, paca_index, "%#-*x");
2367 	DUMP(p, kernel_toc, "%#-*llx");
2368 	DUMP(p, kernelbase, "%#-*llx");
2369 	DUMP(p, kernel_msr, "%#-*llx");
2370 	DUMP(p, emergency_sp, "%-*px");
2371 #ifdef CONFIG_PPC_BOOK3S_64
2372 	DUMP(p, nmi_emergency_sp, "%-*px");
2373 	DUMP(p, mc_emergency_sp, "%-*px");
2374 	DUMP(p, in_nmi, "%#-*x");
2375 	DUMP(p, in_mce, "%#-*x");
2376 	DUMP(p, hmi_event_available, "%#-*x");
2377 #endif
2378 	DUMP(p, data_offset, "%#-*llx");
2379 	DUMP(p, hw_cpu_id, "%#-*x");
2380 	DUMP(p, cpu_start, "%#-*x");
2381 	DUMP(p, kexec_state, "%#-*x");
2382 #ifdef CONFIG_PPC_BOOK3S_64
2383 	if (!early_radix_enabled()) {
2384 		for (i = 0; i < SLB_NUM_BOLTED; i++) {
2385 			u64 esid, vsid;
2386 
2387 			if (!p->slb_shadow_ptr)
2388 				continue;
2389 
2390 			esid = be64_to_cpu(p->slb_shadow_ptr->save_area[i].esid);
2391 			vsid = be64_to_cpu(p->slb_shadow_ptr->save_area[i].vsid);
2392 
2393 			if (esid || vsid) {
2394 				printf(" %-*s[%d] = 0x%016llx 0x%016llx\n",
2395 				       22, "slb_shadow", i, esid, vsid);
2396 			}
2397 		}
2398 		DUMP(p, vmalloc_sllp, "%#-*x");
2399 		DUMP(p, stab_rr, "%#-*x");
2400 		DUMP(p, slb_used_bitmap, "%#-*x");
2401 		DUMP(p, slb_kern_bitmap, "%#-*x");
2402 
2403 		if (!early_cpu_has_feature(CPU_FTR_ARCH_300)) {
2404 			DUMP(p, slb_cache_ptr, "%#-*x");
2405 			for (i = 0; i < SLB_CACHE_ENTRIES; i++)
2406 				printf(" %-*s[%d] = 0x%016x\n",
2407 				       22, "slb_cache", i, p->slb_cache[i]);
2408 		}
2409 	}
2410 
2411 	DUMP(p, rfi_flush_fallback_area, "%-*px");
2412 #endif
2413 	DUMP(p, dscr_default, "%#-*llx");
2414 #ifdef CONFIG_PPC_BOOK3E
2415 	DUMP(p, pgd, "%-*px");
2416 	DUMP(p, kernel_pgd, "%-*px");
2417 	DUMP(p, tcd_ptr, "%-*px");
2418 	DUMP(p, mc_kstack, "%-*px");
2419 	DUMP(p, crit_kstack, "%-*px");
2420 	DUMP(p, dbg_kstack, "%-*px");
2421 #endif
2422 	DUMP(p, __current, "%-*px");
2423 	DUMP(p, kstack, "%#-*llx");
2424 	printf(" %-*s = 0x%016llx\n", 25, "kstack_base", p->kstack & ~(THREAD_SIZE - 1));
2425 #ifdef CONFIG_STACKPROTECTOR
2426 	DUMP(p, canary, "%#-*lx");
2427 #endif
2428 	DUMP(p, saved_r1, "%#-*llx");
2429 	DUMP(p, trap_save, "%#-*x");
2430 	DUMP(p, irq_soft_mask, "%#-*x");
2431 	DUMP(p, irq_happened, "%#-*x");
2432 	DUMP(p, io_sync, "%#-*x");
2433 	DUMP(p, irq_work_pending, "%#-*x");
2434 	DUMP(p, nap_state_lost, "%#-*x");
2435 	DUMP(p, sprg_vdso, "%#-*llx");
2436 
2437 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2438 	DUMP(p, tm_scratch, "%#-*llx");
2439 #endif
2440 
2441 #ifdef CONFIG_PPC_POWERNV
2442 	DUMP(p, core_idle_state_ptr, "%-*px");
2443 	DUMP(p, thread_idle_state, "%#-*x");
2444 	DUMP(p, thread_mask, "%#-*x");
2445 	DUMP(p, subcore_sibling_mask, "%#-*x");
2446 	DUMP(p, requested_psscr, "%#-*llx");
2447 	DUMP(p, stop_sprs.pid, "%#-*llx");
2448 	DUMP(p, stop_sprs.ldbar, "%#-*llx");
2449 	DUMP(p, stop_sprs.fscr, "%#-*llx");
2450 	DUMP(p, stop_sprs.hfscr, "%#-*llx");
2451 	DUMP(p, stop_sprs.mmcr1, "%#-*llx");
2452 	DUMP(p, stop_sprs.mmcr2, "%#-*llx");
2453 	DUMP(p, stop_sprs.mmcra, "%#-*llx");
2454 	DUMP(p, dont_stop.counter, "%#-*x");
2455 #endif
2456 
2457 	DUMP(p, accounting.utime, "%#-*lx");
2458 	DUMP(p, accounting.stime, "%#-*lx");
2459 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
2460 	DUMP(p, accounting.utime_scaled, "%#-*lx");
2461 #endif
2462 	DUMP(p, accounting.starttime, "%#-*lx");
2463 	DUMP(p, accounting.starttime_user, "%#-*lx");
2464 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
2465 	DUMP(p, accounting.startspurr, "%#-*lx");
2466 	DUMP(p, accounting.utime_sspurr, "%#-*lx");
2467 #endif
2468 	DUMP(p, accounting.steal_time, "%#-*lx");
2469 #undef DUMP
2470 
2471 	catch_memory_errors = 0;
2472 	sync();
2473 }
2474 
2475 static void dump_all_pacas(void)
2476 {
2477 	int cpu;
2478 
2479 	if (num_possible_cpus() == 0) {
2480 		printf("No possible cpus, use 'dp #' to dump individual cpus\n");
2481 		return;
2482 	}
2483 
2484 	for_each_possible_cpu(cpu)
2485 		dump_one_paca(cpu);
2486 }
2487 
2488 static void dump_pacas(void)
2489 {
2490 	unsigned long num;
2491 	int c;
2492 
2493 	c = inchar();
2494 	if (c == 'a') {
2495 		dump_all_pacas();
2496 		return;
2497 	}
2498 
2499 	termch = c;	/* Put c back, it wasn't 'a' */
2500 
2501 	if (scanhex(&num))
2502 		dump_one_paca(num);
2503 	else
2504 		dump_one_paca(xmon_owner);
2505 }
2506 #endif
2507 
2508 #ifdef CONFIG_PPC_POWERNV
2509 static void dump_one_xive(int cpu)
2510 {
2511 	unsigned int hwid = get_hard_smp_processor_id(cpu);
2512 
2513 	opal_xive_dump(XIVE_DUMP_TM_HYP, hwid);
2514 	opal_xive_dump(XIVE_DUMP_TM_POOL, hwid);
2515 	opal_xive_dump(XIVE_DUMP_TM_OS, hwid);
2516 	opal_xive_dump(XIVE_DUMP_TM_USER, hwid);
2517 	opal_xive_dump(XIVE_DUMP_VP, hwid);
2518 	opal_xive_dump(XIVE_DUMP_EMU_STATE, hwid);
2519 
2520 	if (setjmp(bus_error_jmp) != 0) {
2521 		catch_memory_errors = 0;
2522 		printf("*** Error dumping xive on cpu %d\n", cpu);
2523 		return;
2524 	}
2525 
2526 	catch_memory_errors = 1;
2527 	sync();
2528 	xmon_xive_do_dump(cpu);
2529 	sync();
2530 	__delay(200);
2531 	catch_memory_errors = 0;
2532 }
2533 
2534 static void dump_all_xives(void)
2535 {
2536 	int cpu;
2537 
2538 	if (num_possible_cpus() == 0) {
2539 		printf("No possible cpus, use 'dx #' to dump individual cpus\n");
2540 		return;
2541 	}
2542 
2543 	for_each_possible_cpu(cpu)
2544 		dump_one_xive(cpu);
2545 }
2546 
2547 static void dump_one_xive_irq(u32 num)
2548 {
2549 	s64 rc;
2550 	__be64 vp;
2551 	u8 prio;
2552 	__be32 lirq;
2553 
2554 	rc = opal_xive_get_irq_config(num, &vp, &prio, &lirq);
2555 	xmon_printf("IRQ 0x%x config: vp=0x%llx prio=%d lirq=0x%x (rc=%lld)\n",
2556 		    num, be64_to_cpu(vp), prio, be32_to_cpu(lirq), rc);
2557 }
2558 
2559 static void dump_xives(void)
2560 {
2561 	unsigned long num;
2562 	int c;
2563 
2564 	if (!xive_enabled()) {
2565 		printf("Xive disabled on this system\n");
2566 		return;
2567 	}
2568 
2569 	c = inchar();
2570 	if (c == 'a') {
2571 		dump_all_xives();
2572 		return;
2573 	} else if (c == 'i') {
2574 		if (scanhex(&num))
2575 			dump_one_xive_irq(num);
2576 		return;
2577 	}
2578 
2579 	termch = c;	/* Put c back, it wasn't 'a' */
2580 
2581 	if (scanhex(&num))
2582 		dump_one_xive(num);
2583 	else
2584 		dump_one_xive(xmon_owner);
2585 }
2586 #endif /* CONFIG_PPC_POWERNV */
2587 
2588 static void dump_by_size(unsigned long addr, long count, int size)
2589 {
2590 	unsigned char temp[16];
2591 	int i, j;
2592 	u64 val;
2593 
2594 	count = ALIGN(count, 16);
2595 
2596 	for (i = 0; i < count; i += 16, addr += 16) {
2597 		printf(REG, addr);
2598 
2599 		if (mread(addr, temp, 16) != 16) {
2600 			printf("\nFaulted reading %d bytes from 0x"REG"\n", 16, addr);
2601 			return;
2602 		}
2603 
2604 		for (j = 0; j < 16; j += size) {
2605 			putchar(' ');
2606 			switch (size) {
2607 			case 1: val = temp[j]; break;
2608 			case 2: val = *(u16 *)&temp[j]; break;
2609 			case 4: val = *(u32 *)&temp[j]; break;
2610 			case 8: val = *(u64 *)&temp[j]; break;
2611 			default: val = 0;
2612 			}
2613 
2614 			printf("%0*llx", size * 2, val);
2615 		}
2616 		printf("\n");
2617 	}
2618 }
2619 
2620 static void
2621 dump(void)
2622 {
2623 	static char last[] = { "d?\n" };
2624 	int c;
2625 
2626 	c = inchar();
2627 
2628 #ifdef CONFIG_PPC64
2629 	if (c == 'p') {
2630 		xmon_start_pagination();
2631 		dump_pacas();
2632 		xmon_end_pagination();
2633 		return;
2634 	}
2635 #endif
2636 #ifdef CONFIG_PPC_POWERNV
2637 	if (c == 'x') {
2638 		xmon_start_pagination();
2639 		dump_xives();
2640 		xmon_end_pagination();
2641 		return;
2642 	}
2643 #endif
2644 
2645 	if (c == 't') {
2646 		dump_tracing();
2647 		return;
2648 	}
2649 
2650 	if (c == '\n')
2651 		termch = c;
2652 
2653 	scanhex((void *)&adrs);
2654 	if (termch != '\n')
2655 		termch = 0;
2656 	if (c == 'i') {
2657 		scanhex(&nidump);
2658 		if (nidump == 0)
2659 			nidump = 16;
2660 		else if (nidump > MAX_DUMP)
2661 			nidump = MAX_DUMP;
2662 		adrs += ppc_inst_dump(adrs, nidump, 1);
2663 		last_cmd = "di\n";
2664 	} else if (c == 'l') {
2665 		dump_log_buf();
2666 	} else if (c == 'o') {
2667 		dump_opal_msglog();
2668 	} else if (c == 'v') {
2669 		/* dump virtual to physical translation */
2670 		show_pte(adrs);
2671 	} else if (c == 'r') {
2672 		scanhex(&ndump);
2673 		if (ndump == 0)
2674 			ndump = 64;
2675 		xmon_rawdump(adrs, ndump);
2676 		adrs += ndump;
2677 		last_cmd = "dr\n";
2678 	} else {
2679 		scanhex(&ndump);
2680 		if (ndump == 0)
2681 			ndump = 64;
2682 		else if (ndump > MAX_DUMP)
2683 			ndump = MAX_DUMP;
2684 
2685 		switch (c) {
2686 		case '8':
2687 		case '4':
2688 		case '2':
2689 		case '1':
2690 			ndump = ALIGN(ndump, 16);
2691 			dump_by_size(adrs, ndump, c - '0');
2692 			last[1] = c;
2693 			last_cmd = last;
2694 			break;
2695 		default:
2696 			prdump(adrs, ndump);
2697 			last_cmd = "d\n";
2698 		}
2699 
2700 		adrs += ndump;
2701 	}
2702 }
2703 
2704 static void
2705 prdump(unsigned long adrs, long ndump)
2706 {
2707 	long n, m, c, r, nr;
2708 	unsigned char temp[16];
2709 
2710 	for (n = ndump; n > 0;) {
2711 		printf(REG, adrs);
2712 		putchar(' ');
2713 		r = n < 16? n: 16;
2714 		nr = mread(adrs, temp, r);
2715 		adrs += nr;
2716 		for (m = 0; m < r; ++m) {
2717 			if ((m & (sizeof(long) - 1)) == 0 && m > 0)
2718 				putchar(' ');
2719 			if (m < nr)
2720 				printf("%.2x", temp[m]);
2721 			else
2722 				printf("%s", fault_chars[fault_type]);
2723 		}
2724 		for (; m < 16; ++m) {
2725 			if ((m & (sizeof(long) - 1)) == 0)
2726 				putchar(' ');
2727 			printf("  ");
2728 		}
2729 		printf("  |");
2730 		for (m = 0; m < r; ++m) {
2731 			if (m < nr) {
2732 				c = temp[m];
2733 				putchar(' ' <= c && c <= '~'? c: '.');
2734 			} else
2735 				putchar(' ');
2736 		}
2737 		n -= r;
2738 		for (; m < 16; ++m)
2739 			putchar(' ');
2740 		printf("|\n");
2741 		if (nr < r)
2742 			break;
2743 	}
2744 }
2745 
2746 typedef int (*instruction_dump_func)(unsigned long inst, unsigned long addr);
2747 
2748 static int
2749 generic_inst_dump(unsigned long adr, long count, int praddr,
2750 			instruction_dump_func dump_func)
2751 {
2752 	int nr, dotted;
2753 	unsigned long first_adr;
2754 	unsigned int inst, last_inst = 0;
2755 	unsigned char val[4];
2756 
2757 	dotted = 0;
2758 	for (first_adr = adr; count > 0; --count, adr += 4) {
2759 		nr = mread(adr, val, 4);
2760 		if (nr == 0) {
2761 			if (praddr) {
2762 				const char *x = fault_chars[fault_type];
2763 				printf(REG"  %s%s%s%s\n", adr, x, x, x, x);
2764 			}
2765 			break;
2766 		}
2767 		inst = GETWORD(val);
2768 		if (adr > first_adr && inst == last_inst) {
2769 			if (!dotted) {
2770 				printf(" ...\n");
2771 				dotted = 1;
2772 			}
2773 			continue;
2774 		}
2775 		dotted = 0;
2776 		last_inst = inst;
2777 		if (praddr)
2778 			printf(REG"  %.8x", adr, inst);
2779 		printf("\t");
2780 		dump_func(inst, adr);
2781 		printf("\n");
2782 	}
2783 	return adr - first_adr;
2784 }
2785 
2786 static int
2787 ppc_inst_dump(unsigned long adr, long count, int praddr)
2788 {
2789 	return generic_inst_dump(adr, count, praddr, print_insn_powerpc);
2790 }
2791 
2792 void
2793 print_address(unsigned long addr)
2794 {
2795 	xmon_print_symbol(addr, "\t# ", "");
2796 }
2797 
2798 static void
2799 dump_log_buf(void)
2800 {
2801 	struct kmsg_dumper dumper = { .active = 1 };
2802 	unsigned char buf[128];
2803 	size_t len;
2804 
2805 	if (setjmp(bus_error_jmp) != 0) {
2806 		printf("Error dumping printk buffer!\n");
2807 		return;
2808 	}
2809 
2810 	catch_memory_errors = 1;
2811 	sync();
2812 
2813 	kmsg_dump_rewind_nolock(&dumper);
2814 	xmon_start_pagination();
2815 	while (kmsg_dump_get_line_nolock(&dumper, false, buf, sizeof(buf), &len)) {
2816 		buf[len] = '\0';
2817 		printf("%s", buf);
2818 	}
2819 	xmon_end_pagination();
2820 
2821 	sync();
2822 	/* wait a little while to see if we get a machine check */
2823 	__delay(200);
2824 	catch_memory_errors = 0;
2825 }
2826 
2827 #ifdef CONFIG_PPC_POWERNV
2828 static void dump_opal_msglog(void)
2829 {
2830 	unsigned char buf[128];
2831 	ssize_t res;
2832 	loff_t pos = 0;
2833 
2834 	if (!firmware_has_feature(FW_FEATURE_OPAL)) {
2835 		printf("Machine is not running OPAL firmware.\n");
2836 		return;
2837 	}
2838 
2839 	if (setjmp(bus_error_jmp) != 0) {
2840 		printf("Error dumping OPAL msglog!\n");
2841 		return;
2842 	}
2843 
2844 	catch_memory_errors = 1;
2845 	sync();
2846 
2847 	xmon_start_pagination();
2848 	while ((res = opal_msglog_copy(buf, pos, sizeof(buf) - 1))) {
2849 		if (res < 0) {
2850 			printf("Error dumping OPAL msglog! Error: %zd\n", res);
2851 			break;
2852 		}
2853 		buf[res] = '\0';
2854 		printf("%s", buf);
2855 		pos += res;
2856 	}
2857 	xmon_end_pagination();
2858 
2859 	sync();
2860 	/* wait a little while to see if we get a machine check */
2861 	__delay(200);
2862 	catch_memory_errors = 0;
2863 }
2864 #endif
2865 
2866 /*
2867  * Memory operations - move, set, print differences
2868  */
2869 static unsigned long mdest;		/* destination address */
2870 static unsigned long msrc;		/* source address */
2871 static unsigned long mval;		/* byte value to set memory to */
2872 static unsigned long mcount;		/* # bytes to affect */
2873 static unsigned long mdiffs;		/* max # differences to print */
2874 
2875 static void
2876 memops(int cmd)
2877 {
2878 	scanhex((void *)&mdest);
2879 	if( termch != '\n' )
2880 		termch = 0;
2881 	scanhex((void *)(cmd == 's'? &mval: &msrc));
2882 	if( termch != '\n' )
2883 		termch = 0;
2884 	scanhex((void *)&mcount);
2885 	switch( cmd ){
2886 	case 'm':
2887 		memmove((void *)mdest, (void *)msrc, mcount);
2888 		break;
2889 	case 's':
2890 		memset((void *)mdest, mval, mcount);
2891 		break;
2892 	case 'd':
2893 		if( termch != '\n' )
2894 			termch = 0;
2895 		scanhex((void *)&mdiffs);
2896 		memdiffs((unsigned char *)mdest, (unsigned char *)msrc, mcount, mdiffs);
2897 		break;
2898 	}
2899 }
2900 
2901 static void
2902 memdiffs(unsigned char *p1, unsigned char *p2, unsigned nb, unsigned maxpr)
2903 {
2904 	unsigned n, prt;
2905 
2906 	prt = 0;
2907 	for( n = nb; n > 0; --n )
2908 		if( *p1++ != *p2++ )
2909 			if( ++prt <= maxpr )
2910 				printf("%px %.2x # %px %.2x\n", p1 - 1,
2911 					p1[-1], p2 - 1, p2[-1]);
2912 	if( prt > maxpr )
2913 		printf("Total of %d differences\n", prt);
2914 }
2915 
2916 static unsigned mend;
2917 static unsigned mask;
2918 
2919 static void
2920 memlocate(void)
2921 {
2922 	unsigned a, n;
2923 	unsigned char val[4];
2924 
2925 	last_cmd = "ml";
2926 	scanhex((void *)&mdest);
2927 	if (termch != '\n') {
2928 		termch = 0;
2929 		scanhex((void *)&mend);
2930 		if (termch != '\n') {
2931 			termch = 0;
2932 			scanhex((void *)&mval);
2933 			mask = ~0;
2934 			if (termch != '\n') termch = 0;
2935 			scanhex((void *)&mask);
2936 		}
2937 	}
2938 	n = 0;
2939 	for (a = mdest; a < mend; a += 4) {
2940 		if (mread(a, val, 4) == 4
2941 			&& ((GETWORD(val) ^ mval) & mask) == 0) {
2942 			printf("%.16x:  %.16x\n", a, GETWORD(val));
2943 			if (++n >= 10)
2944 				break;
2945 		}
2946 	}
2947 }
2948 
2949 static unsigned long mskip = 0x1000;
2950 static unsigned long mlim = 0xffffffff;
2951 
2952 static void
2953 memzcan(void)
2954 {
2955 	unsigned char v;
2956 	unsigned a;
2957 	int ok, ook;
2958 
2959 	scanhex(&mdest);
2960 	if (termch != '\n') termch = 0;
2961 	scanhex(&mskip);
2962 	if (termch != '\n') termch = 0;
2963 	scanhex(&mlim);
2964 	ook = 0;
2965 	for (a = mdest; a < mlim; a += mskip) {
2966 		ok = mread(a, &v, 1);
2967 		if (ok && !ook) {
2968 			printf("%.8x .. ", a);
2969 		} else if (!ok && ook)
2970 			printf("%.8lx\n", a - mskip);
2971 		ook = ok;
2972 		if (a + mskip < a)
2973 			break;
2974 	}
2975 	if (ook)
2976 		printf("%.8lx\n", a - mskip);
2977 }
2978 
2979 static void show_task(struct task_struct *tsk)
2980 {
2981 	char state;
2982 
2983 	/*
2984 	 * Cloned from kdb_task_state_char(), which is not entirely
2985 	 * appropriate for calling from xmon. This could be moved
2986 	 * to a common, generic, routine used by both.
2987 	 */
2988 	state = (tsk->state == 0) ? 'R' :
2989 		(tsk->state < 0) ? 'U' :
2990 		(tsk->state & TASK_UNINTERRUPTIBLE) ? 'D' :
2991 		(tsk->state & TASK_STOPPED) ? 'T' :
2992 		(tsk->state & TASK_TRACED) ? 'C' :
2993 		(tsk->exit_state & EXIT_ZOMBIE) ? 'Z' :
2994 		(tsk->exit_state & EXIT_DEAD) ? 'E' :
2995 		(tsk->state & TASK_INTERRUPTIBLE) ? 'S' : '?';
2996 
2997 	printf("%px %016lx %6d %6d %c %2d %s\n", tsk,
2998 		tsk->thread.ksp,
2999 		tsk->pid, rcu_dereference(tsk->parent)->pid,
3000 		state, task_thread_info(tsk)->cpu,
3001 		tsk->comm);
3002 }
3003 
3004 #ifdef CONFIG_PPC_BOOK3S_64
3005 static void format_pte(void *ptep, unsigned long pte)
3006 {
3007 	pte_t entry = __pte(pte);
3008 
3009 	printf("ptep @ 0x%016lx = 0x%016lx\n", (unsigned long)ptep, pte);
3010 	printf("Maps physical address = 0x%016lx\n", pte & PTE_RPN_MASK);
3011 
3012 	printf("Flags = %s%s%s%s%s\n",
3013 	       pte_young(entry) ? "Accessed " : "",
3014 	       pte_dirty(entry) ? "Dirty " : "",
3015 	       pte_read(entry)  ? "Read " : "",
3016 	       pte_write(entry) ? "Write " : "",
3017 	       pte_exec(entry)  ? "Exec " : "");
3018 }
3019 
3020 static void show_pte(unsigned long addr)
3021 {
3022 	unsigned long tskv = 0;
3023 	struct task_struct *tsk = NULL;
3024 	struct mm_struct *mm;
3025 	pgd_t *pgdp, *pgdir;
3026 	pud_t *pudp;
3027 	pmd_t *pmdp;
3028 	pte_t *ptep;
3029 
3030 	if (!scanhex(&tskv))
3031 		mm = &init_mm;
3032 	else
3033 		tsk = (struct task_struct *)tskv;
3034 
3035 	if (tsk == NULL)
3036 		mm = &init_mm;
3037 	else
3038 		mm = tsk->active_mm;
3039 
3040 	if (setjmp(bus_error_jmp) != 0) {
3041 		catch_memory_errors = 0;
3042 		printf("*** Error dumping pte for task %px\n", tsk);
3043 		return;
3044 	}
3045 
3046 	catch_memory_errors = 1;
3047 	sync();
3048 
3049 	if (mm == &init_mm) {
3050 		pgdp = pgd_offset_k(addr);
3051 		pgdir = pgd_offset_k(0);
3052 	} else {
3053 		pgdp = pgd_offset(mm, addr);
3054 		pgdir = pgd_offset(mm, 0);
3055 	}
3056 
3057 	if (pgd_none(*pgdp)) {
3058 		printf("no linux page table for address\n");
3059 		return;
3060 	}
3061 
3062 	printf("pgd  @ 0x%px\n", pgdir);
3063 
3064 	if (pgd_huge(*pgdp)) {
3065 		format_pte(pgdp, pgd_val(*pgdp));
3066 		return;
3067 	}
3068 	printf("pgdp @ 0x%px = 0x%016lx\n", pgdp, pgd_val(*pgdp));
3069 
3070 	pudp = pud_offset(pgdp, addr);
3071 
3072 	if (pud_none(*pudp)) {
3073 		printf("No valid PUD\n");
3074 		return;
3075 	}
3076 
3077 	if (pud_huge(*pudp)) {
3078 		format_pte(pudp, pud_val(*pudp));
3079 		return;
3080 	}
3081 
3082 	printf("pudp @ 0x%px = 0x%016lx\n", pudp, pud_val(*pudp));
3083 
3084 	pmdp = pmd_offset(pudp, addr);
3085 
3086 	if (pmd_none(*pmdp)) {
3087 		printf("No valid PMD\n");
3088 		return;
3089 	}
3090 
3091 	if (pmd_huge(*pmdp)) {
3092 		format_pte(pmdp, pmd_val(*pmdp));
3093 		return;
3094 	}
3095 	printf("pmdp @ 0x%px = 0x%016lx\n", pmdp, pmd_val(*pmdp));
3096 
3097 	ptep = pte_offset_map(pmdp, addr);
3098 	if (pte_none(*ptep)) {
3099 		printf("no valid PTE\n");
3100 		return;
3101 	}
3102 
3103 	format_pte(ptep, pte_val(*ptep));
3104 
3105 	sync();
3106 	__delay(200);
3107 	catch_memory_errors = 0;
3108 }
3109 #else
3110 static void show_pte(unsigned long addr)
3111 {
3112 	printf("show_pte not yet implemented\n");
3113 }
3114 #endif /* CONFIG_PPC_BOOK3S_64 */
3115 
3116 static void show_tasks(void)
3117 {
3118 	unsigned long tskv;
3119 	struct task_struct *tsk = NULL;
3120 
3121 	printf("     task_struct     ->thread.ksp    PID   PPID S  P CMD\n");
3122 
3123 	if (scanhex(&tskv))
3124 		tsk = (struct task_struct *)tskv;
3125 
3126 	if (setjmp(bus_error_jmp) != 0) {
3127 		catch_memory_errors = 0;
3128 		printf("*** Error dumping task %px\n", tsk);
3129 		return;
3130 	}
3131 
3132 	catch_memory_errors = 1;
3133 	sync();
3134 
3135 	if (tsk)
3136 		show_task(tsk);
3137 	else
3138 		for_each_process(tsk)
3139 			show_task(tsk);
3140 
3141 	sync();
3142 	__delay(200);
3143 	catch_memory_errors = 0;
3144 }
3145 
3146 static void proccall(void)
3147 {
3148 	unsigned long args[8];
3149 	unsigned long ret;
3150 	int i;
3151 	typedef unsigned long (*callfunc_t)(unsigned long, unsigned long,
3152 			unsigned long, unsigned long, unsigned long,
3153 			unsigned long, unsigned long, unsigned long);
3154 	callfunc_t func;
3155 
3156 	if (!scanhex(&adrs))
3157 		return;
3158 	if (termch != '\n')
3159 		termch = 0;
3160 	for (i = 0; i < 8; ++i)
3161 		args[i] = 0;
3162 	for (i = 0; i < 8; ++i) {
3163 		if (!scanhex(&args[i]) || termch == '\n')
3164 			break;
3165 		termch = 0;
3166 	}
3167 	func = (callfunc_t) adrs;
3168 	ret = 0;
3169 	if (setjmp(bus_error_jmp) == 0) {
3170 		catch_memory_errors = 1;
3171 		sync();
3172 		ret = func(args[0], args[1], args[2], args[3],
3173 			   args[4], args[5], args[6], args[7]);
3174 		sync();
3175 		printf("return value is 0x%lx\n", ret);
3176 	} else {
3177 		printf("*** %x exception occurred\n", fault_except);
3178 	}
3179 	catch_memory_errors = 0;
3180 }
3181 
3182 /* Input scanning routines */
3183 int
3184 skipbl(void)
3185 {
3186 	int c;
3187 
3188 	if( termch != 0 ){
3189 		c = termch;
3190 		termch = 0;
3191 	} else
3192 		c = inchar();
3193 	while( c == ' ' || c == '\t' )
3194 		c = inchar();
3195 	return c;
3196 }
3197 
3198 #define N_PTREGS	44
3199 static const char *regnames[N_PTREGS] = {
3200 	"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
3201 	"r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
3202 	"r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
3203 	"r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31",
3204 	"pc", "msr", "or3", "ctr", "lr", "xer", "ccr",
3205 #ifdef CONFIG_PPC64
3206 	"softe",
3207 #else
3208 	"mq",
3209 #endif
3210 	"trap", "dar", "dsisr", "res"
3211 };
3212 
3213 int
3214 scanhex(unsigned long *vp)
3215 {
3216 	int c, d;
3217 	unsigned long v;
3218 
3219 	c = skipbl();
3220 	if (c == '%') {
3221 		/* parse register name */
3222 		char regname[8];
3223 		int i;
3224 
3225 		for (i = 0; i < sizeof(regname) - 1; ++i) {
3226 			c = inchar();
3227 			if (!isalnum(c)) {
3228 				termch = c;
3229 				break;
3230 			}
3231 			regname[i] = c;
3232 		}
3233 		regname[i] = 0;
3234 		i = match_string(regnames, N_PTREGS, regname);
3235 		if (i < 0) {
3236 			printf("invalid register name '%%%s'\n", regname);
3237 			return 0;
3238 		}
3239 		if (xmon_regs == NULL) {
3240 			printf("regs not available\n");
3241 			return 0;
3242 		}
3243 		*vp = ((unsigned long *)xmon_regs)[i];
3244 		return 1;
3245 	}
3246 
3247 	/* skip leading "0x" if any */
3248 
3249 	if (c == '0') {
3250 		c = inchar();
3251 		if (c == 'x') {
3252 			c = inchar();
3253 		} else {
3254 			d = hexdigit(c);
3255 			if (d == EOF) {
3256 				termch = c;
3257 				*vp = 0;
3258 				return 1;
3259 			}
3260 		}
3261 	} else if (c == '$') {
3262 		int i;
3263 		for (i=0; i<63; i++) {
3264 			c = inchar();
3265 			if (isspace(c) || c == '\0') {
3266 				termch = c;
3267 				break;
3268 			}
3269 			tmpstr[i] = c;
3270 		}
3271 		tmpstr[i++] = 0;
3272 		*vp = 0;
3273 		if (setjmp(bus_error_jmp) == 0) {
3274 			catch_memory_errors = 1;
3275 			sync();
3276 			*vp = kallsyms_lookup_name(tmpstr);
3277 			sync();
3278 		}
3279 		catch_memory_errors = 0;
3280 		if (!(*vp)) {
3281 			printf("unknown symbol '%s'\n", tmpstr);
3282 			return 0;
3283 		}
3284 		return 1;
3285 	}
3286 
3287 	d = hexdigit(c);
3288 	if (d == EOF) {
3289 		termch = c;
3290 		return 0;
3291 	}
3292 	v = 0;
3293 	do {
3294 		v = (v << 4) + d;
3295 		c = inchar();
3296 		d = hexdigit(c);
3297 	} while (d != EOF);
3298 	termch = c;
3299 	*vp = v;
3300 	return 1;
3301 }
3302 
3303 static void
3304 scannl(void)
3305 {
3306 	int c;
3307 
3308 	c = termch;
3309 	termch = 0;
3310 	while( c != '\n' )
3311 		c = inchar();
3312 }
3313 
3314 static int hexdigit(int c)
3315 {
3316 	if( '0' <= c && c <= '9' )
3317 		return c - '0';
3318 	if( 'A' <= c && c <= 'F' )
3319 		return c - ('A' - 10);
3320 	if( 'a' <= c && c <= 'f' )
3321 		return c - ('a' - 10);
3322 	return EOF;
3323 }
3324 
3325 void
3326 getstring(char *s, int size)
3327 {
3328 	int c;
3329 
3330 	c = skipbl();
3331 	do {
3332 		if( size > 1 ){
3333 			*s++ = c;
3334 			--size;
3335 		}
3336 		c = inchar();
3337 	} while( c != ' ' && c != '\t' && c != '\n' );
3338 	termch = c;
3339 	*s = 0;
3340 }
3341 
3342 static char line[256];
3343 static char *lineptr;
3344 
3345 static void
3346 flush_input(void)
3347 {
3348 	lineptr = NULL;
3349 }
3350 
3351 static int
3352 inchar(void)
3353 {
3354 	if (lineptr == NULL || *lineptr == 0) {
3355 		if (xmon_gets(line, sizeof(line)) == NULL) {
3356 			lineptr = NULL;
3357 			return EOF;
3358 		}
3359 		lineptr = line;
3360 	}
3361 	return *lineptr++;
3362 }
3363 
3364 static void
3365 take_input(char *str)
3366 {
3367 	lineptr = str;
3368 }
3369 
3370 
3371 static void
3372 symbol_lookup(void)
3373 {
3374 	int type = inchar();
3375 	unsigned long addr, cpu;
3376 	void __percpu *ptr = NULL;
3377 	static char tmp[64];
3378 
3379 	switch (type) {
3380 	case 'a':
3381 		if (scanhex(&addr))
3382 			xmon_print_symbol(addr, ": ", "\n");
3383 		termch = 0;
3384 		break;
3385 	case 's':
3386 		getstring(tmp, 64);
3387 		if (setjmp(bus_error_jmp) == 0) {
3388 			catch_memory_errors = 1;
3389 			sync();
3390 			addr = kallsyms_lookup_name(tmp);
3391 			if (addr)
3392 				printf("%s: %lx\n", tmp, addr);
3393 			else
3394 				printf("Symbol '%s' not found.\n", tmp);
3395 			sync();
3396 		}
3397 		catch_memory_errors = 0;
3398 		termch = 0;
3399 		break;
3400 	case 'p':
3401 		getstring(tmp, 64);
3402 		if (setjmp(bus_error_jmp) == 0) {
3403 			catch_memory_errors = 1;
3404 			sync();
3405 			ptr = (void __percpu *)kallsyms_lookup_name(tmp);
3406 			sync();
3407 		}
3408 
3409 		if (ptr &&
3410 		    ptr >= (void __percpu *)__per_cpu_start &&
3411 		    ptr < (void __percpu *)__per_cpu_end)
3412 		{
3413 			if (scanhex(&cpu) && cpu < num_possible_cpus()) {
3414 				addr = (unsigned long)per_cpu_ptr(ptr, cpu);
3415 			} else {
3416 				cpu = raw_smp_processor_id();
3417 				addr = (unsigned long)this_cpu_ptr(ptr);
3418 			}
3419 
3420 			printf("%s for cpu 0x%lx: %lx\n", tmp, cpu, addr);
3421 		} else {
3422 			printf("Percpu symbol '%s' not found.\n", tmp);
3423 		}
3424 
3425 		catch_memory_errors = 0;
3426 		termch = 0;
3427 		break;
3428 	}
3429 }
3430 
3431 
3432 /* Print an address in numeric and symbolic form (if possible) */
3433 static void xmon_print_symbol(unsigned long address, const char *mid,
3434 			      const char *after)
3435 {
3436 	char *modname;
3437 	const char *name = NULL;
3438 	unsigned long offset, size;
3439 
3440 	printf(REG, address);
3441 	if (setjmp(bus_error_jmp) == 0) {
3442 		catch_memory_errors = 1;
3443 		sync();
3444 		name = kallsyms_lookup(address, &size, &offset, &modname,
3445 				       tmpstr);
3446 		sync();
3447 		/* wait a little while to see if we get a machine check */
3448 		__delay(200);
3449 	}
3450 
3451 	catch_memory_errors = 0;
3452 
3453 	if (name) {
3454 		printf("%s%s+%#lx/%#lx", mid, name, offset, size);
3455 		if (modname)
3456 			printf(" [%s]", modname);
3457 	}
3458 	printf("%s", after);
3459 }
3460 
3461 #ifdef CONFIG_PPC_BOOK3S_64
3462 void dump_segments(void)
3463 {
3464 	int i;
3465 	unsigned long esid,vsid;
3466 	unsigned long llp;
3467 
3468 	printf("SLB contents of cpu 0x%x\n", smp_processor_id());
3469 
3470 	for (i = 0; i < mmu_slb_size; i++) {
3471 		asm volatile("slbmfee  %0,%1" : "=r" (esid) : "r" (i));
3472 		asm volatile("slbmfev  %0,%1" : "=r" (vsid) : "r" (i));
3473 
3474 		if (!esid && !vsid)
3475 			continue;
3476 
3477 		printf("%02d %016lx %016lx", i, esid, vsid);
3478 
3479 		if (!(esid & SLB_ESID_V)) {
3480 			printf("\n");
3481 			continue;
3482 		}
3483 
3484 		llp = vsid & SLB_VSID_LLP;
3485 		if (vsid & SLB_VSID_B_1T) {
3486 			printf("  1T  ESID=%9lx  VSID=%13lx LLP:%3lx \n",
3487 				GET_ESID_1T(esid),
3488 				(vsid & ~SLB_VSID_B) >> SLB_VSID_SHIFT_1T,
3489 				llp);
3490 		} else {
3491 			printf(" 256M ESID=%9lx  VSID=%13lx LLP:%3lx \n",
3492 				GET_ESID(esid),
3493 				(vsid & ~SLB_VSID_B) >> SLB_VSID_SHIFT,
3494 				llp);
3495 		}
3496 	}
3497 }
3498 #endif
3499 
3500 #ifdef CONFIG_PPC_BOOK3S_32
3501 void dump_segments(void)
3502 {
3503 	int i;
3504 
3505 	printf("sr0-15 =");
3506 	for (i = 0; i < 16; ++i)
3507 		printf(" %x", mfsrin(i << 28));
3508 	printf("\n");
3509 }
3510 #endif
3511 
3512 #ifdef CONFIG_44x
3513 static void dump_tlb_44x(void)
3514 {
3515 	int i;
3516 
3517 	for (i = 0; i < PPC44x_TLB_SIZE; i++) {
3518 		unsigned long w0,w1,w2;
3519 		asm volatile("tlbre  %0,%1,0" : "=r" (w0) : "r" (i));
3520 		asm volatile("tlbre  %0,%1,1" : "=r" (w1) : "r" (i));
3521 		asm volatile("tlbre  %0,%1,2" : "=r" (w2) : "r" (i));
3522 		printf("[%02x] %08lx %08lx %08lx ", i, w0, w1, w2);
3523 		if (w0 & PPC44x_TLB_VALID) {
3524 			printf("V %08lx -> %01lx%08lx %c%c%c%c%c",
3525 			       w0 & PPC44x_TLB_EPN_MASK,
3526 			       w1 & PPC44x_TLB_ERPN_MASK,
3527 			       w1 & PPC44x_TLB_RPN_MASK,
3528 			       (w2 & PPC44x_TLB_W) ? 'W' : 'w',
3529 			       (w2 & PPC44x_TLB_I) ? 'I' : 'i',
3530 			       (w2 & PPC44x_TLB_M) ? 'M' : 'm',
3531 			       (w2 & PPC44x_TLB_G) ? 'G' : 'g',
3532 			       (w2 & PPC44x_TLB_E) ? 'E' : 'e');
3533 		}
3534 		printf("\n");
3535 	}
3536 }
3537 #endif /* CONFIG_44x */
3538 
3539 #ifdef CONFIG_PPC_BOOK3E
3540 static void dump_tlb_book3e(void)
3541 {
3542 	u32 mmucfg, pidmask, lpidmask;
3543 	u64 ramask;
3544 	int i, tlb, ntlbs, pidsz, lpidsz, rasz, lrat = 0;
3545 	int mmu_version;
3546 	static const char *pgsz_names[] = {
3547 		"  1K",
3548 		"  2K",
3549 		"  4K",
3550 		"  8K",
3551 		" 16K",
3552 		" 32K",
3553 		" 64K",
3554 		"128K",
3555 		"256K",
3556 		"512K",
3557 		"  1M",
3558 		"  2M",
3559 		"  4M",
3560 		"  8M",
3561 		" 16M",
3562 		" 32M",
3563 		" 64M",
3564 		"128M",
3565 		"256M",
3566 		"512M",
3567 		"  1G",
3568 		"  2G",
3569 		"  4G",
3570 		"  8G",
3571 		" 16G",
3572 		" 32G",
3573 		" 64G",
3574 		"128G",
3575 		"256G",
3576 		"512G",
3577 		"  1T",
3578 		"  2T",
3579 	};
3580 
3581 	/* Gather some infos about the MMU */
3582 	mmucfg = mfspr(SPRN_MMUCFG);
3583 	mmu_version = (mmucfg & 3) + 1;
3584 	ntlbs = ((mmucfg >> 2) & 3) + 1;
3585 	pidsz = ((mmucfg >> 6) & 0x1f) + 1;
3586 	lpidsz = (mmucfg >> 24) & 0xf;
3587 	rasz = (mmucfg >> 16) & 0x7f;
3588 	if ((mmu_version > 1) && (mmucfg & 0x10000))
3589 		lrat = 1;
3590 	printf("Book3E MMU MAV=%d.0,%d TLBs,%d-bit PID,%d-bit LPID,%d-bit RA\n",
3591 	       mmu_version, ntlbs, pidsz, lpidsz, rasz);
3592 	pidmask = (1ul << pidsz) - 1;
3593 	lpidmask = (1ul << lpidsz) - 1;
3594 	ramask = (1ull << rasz) - 1;
3595 
3596 	for (tlb = 0; tlb < ntlbs; tlb++) {
3597 		u32 tlbcfg;
3598 		int nent, assoc, new_cc = 1;
3599 		printf("TLB %d:\n------\n", tlb);
3600 		switch(tlb) {
3601 		case 0:
3602 			tlbcfg = mfspr(SPRN_TLB0CFG);
3603 			break;
3604 		case 1:
3605 			tlbcfg = mfspr(SPRN_TLB1CFG);
3606 			break;
3607 		case 2:
3608 			tlbcfg = mfspr(SPRN_TLB2CFG);
3609 			break;
3610 		case 3:
3611 			tlbcfg = mfspr(SPRN_TLB3CFG);
3612 			break;
3613 		default:
3614 			printf("Unsupported TLB number !\n");
3615 			continue;
3616 		}
3617 		nent = tlbcfg & 0xfff;
3618 		assoc = (tlbcfg >> 24) & 0xff;
3619 		for (i = 0; i < nent; i++) {
3620 			u32 mas0 = MAS0_TLBSEL(tlb);
3621 			u32 mas1 = MAS1_TSIZE(BOOK3E_PAGESZ_4K);
3622 			u64 mas2 = 0;
3623 			u64 mas7_mas3;
3624 			int esel = i, cc = i;
3625 
3626 			if (assoc != 0) {
3627 				cc = i / assoc;
3628 				esel = i % assoc;
3629 				mas2 = cc * 0x1000;
3630 			}
3631 
3632 			mas0 |= MAS0_ESEL(esel);
3633 			mtspr(SPRN_MAS0, mas0);
3634 			mtspr(SPRN_MAS1, mas1);
3635 			mtspr(SPRN_MAS2, mas2);
3636 			asm volatile("tlbre  0,0,0" : : : "memory");
3637 			mas1 = mfspr(SPRN_MAS1);
3638 			mas2 = mfspr(SPRN_MAS2);
3639 			mas7_mas3 = mfspr(SPRN_MAS7_MAS3);
3640 			if (assoc && (i % assoc) == 0)
3641 				new_cc = 1;
3642 			if (!(mas1 & MAS1_VALID))
3643 				continue;
3644 			if (assoc == 0)
3645 				printf("%04x- ", i);
3646 			else if (new_cc)
3647 				printf("%04x-%c", cc, 'A' + esel);
3648 			else
3649 				printf("    |%c", 'A' + esel);
3650 			new_cc = 0;
3651 			printf(" %016llx %04x %s %c%c AS%c",
3652 			       mas2 & ~0x3ffull,
3653 			       (mas1 >> 16) & 0x3fff,
3654 			       pgsz_names[(mas1 >> 7) & 0x1f],
3655 			       mas1 & MAS1_IND ? 'I' : ' ',
3656 			       mas1 & MAS1_IPROT ? 'P' : ' ',
3657 			       mas1 & MAS1_TS ? '1' : '0');
3658 			printf(" %c%c%c%c%c%c%c",
3659 			       mas2 & MAS2_X0 ? 'a' : ' ',
3660 			       mas2 & MAS2_X1 ? 'v' : ' ',
3661 			       mas2 & MAS2_W  ? 'w' : ' ',
3662 			       mas2 & MAS2_I  ? 'i' : ' ',
3663 			       mas2 & MAS2_M  ? 'm' : ' ',
3664 			       mas2 & MAS2_G  ? 'g' : ' ',
3665 			       mas2 & MAS2_E  ? 'e' : ' ');
3666 			printf(" %016llx", mas7_mas3 & ramask & ~0x7ffull);
3667 			if (mas1 & MAS1_IND)
3668 				printf(" %s\n",
3669 				       pgsz_names[(mas7_mas3 >> 1) & 0x1f]);
3670 			else
3671 				printf(" U%c%c%c S%c%c%c\n",
3672 				       mas7_mas3 & MAS3_UX ? 'x' : ' ',
3673 				       mas7_mas3 & MAS3_UW ? 'w' : ' ',
3674 				       mas7_mas3 & MAS3_UR ? 'r' : ' ',
3675 				       mas7_mas3 & MAS3_SX ? 'x' : ' ',
3676 				       mas7_mas3 & MAS3_SW ? 'w' : ' ',
3677 				       mas7_mas3 & MAS3_SR ? 'r' : ' ');
3678 		}
3679 	}
3680 }
3681 #endif /* CONFIG_PPC_BOOK3E */
3682 
3683 static void xmon_init(int enable)
3684 {
3685 	if (enable) {
3686 		__debugger = xmon;
3687 		__debugger_ipi = xmon_ipi;
3688 		__debugger_bpt = xmon_bpt;
3689 		__debugger_sstep = xmon_sstep;
3690 		__debugger_iabr_match = xmon_iabr_match;
3691 		__debugger_break_match = xmon_break_match;
3692 		__debugger_fault_handler = xmon_fault_handler;
3693 
3694 #ifdef CONFIG_PPC_PSERIES
3695 		/*
3696 		 * Get the token here to avoid trying to get a lock
3697 		 * during the crash, causing a deadlock.
3698 		 */
3699 		set_indicator_token = rtas_token("set-indicator");
3700 #endif
3701 	} else {
3702 		__debugger = NULL;
3703 		__debugger_ipi = NULL;
3704 		__debugger_bpt = NULL;
3705 		__debugger_sstep = NULL;
3706 		__debugger_iabr_match = NULL;
3707 		__debugger_break_match = NULL;
3708 		__debugger_fault_handler = NULL;
3709 	}
3710 }
3711 
3712 #ifdef CONFIG_MAGIC_SYSRQ
3713 static void sysrq_handle_xmon(int key)
3714 {
3715 	/* ensure xmon is enabled */
3716 	xmon_init(1);
3717 	debugger(get_irq_regs());
3718 	if (!xmon_on)
3719 		xmon_init(0);
3720 }
3721 
3722 static struct sysrq_key_op sysrq_xmon_op = {
3723 	.handler =	sysrq_handle_xmon,
3724 	.help_msg =	"xmon(x)",
3725 	.action_msg =	"Entering xmon",
3726 };
3727 
3728 static int __init setup_xmon_sysrq(void)
3729 {
3730 	register_sysrq_key('x', &sysrq_xmon_op);
3731 	return 0;
3732 }
3733 device_initcall(setup_xmon_sysrq);
3734 #endif /* CONFIG_MAGIC_SYSRQ */
3735 
3736 #ifdef CONFIG_DEBUG_FS
3737 static void clear_all_bpt(void)
3738 {
3739 	int i;
3740 
3741 	/* clear/unpatch all breakpoints */
3742 	remove_bpts();
3743 	remove_cpu_bpts();
3744 
3745 	/* Disable all breakpoints */
3746 	for (i = 0; i < NBPTS; ++i)
3747 		bpts[i].enabled = 0;
3748 
3749 	/* Clear any data or iabr breakpoints */
3750 	if (iabr || dabr.enabled) {
3751 		iabr = NULL;
3752 		dabr.enabled = 0;
3753 	}
3754 
3755 	printf("xmon: All breakpoints cleared\n");
3756 }
3757 
3758 static int xmon_dbgfs_set(void *data, u64 val)
3759 {
3760 	xmon_on = !!val;
3761 	xmon_init(xmon_on);
3762 
3763 	/* make sure all breakpoints removed when disabling */
3764 	if (!xmon_on)
3765 		clear_all_bpt();
3766 	return 0;
3767 }
3768 
3769 static int xmon_dbgfs_get(void *data, u64 *val)
3770 {
3771 	*val = xmon_on;
3772 	return 0;
3773 }
3774 
3775 DEFINE_SIMPLE_ATTRIBUTE(xmon_dbgfs_ops, xmon_dbgfs_get,
3776 			xmon_dbgfs_set, "%llu\n");
3777 
3778 static int __init setup_xmon_dbgfs(void)
3779 {
3780 	debugfs_create_file("xmon", 0600, powerpc_debugfs_root, NULL,
3781 				&xmon_dbgfs_ops);
3782 	return 0;
3783 }
3784 device_initcall(setup_xmon_dbgfs);
3785 #endif /* CONFIG_DEBUG_FS */
3786 
3787 static int xmon_early __initdata;
3788 
3789 static int __init early_parse_xmon(char *p)
3790 {
3791 	if (!p || strncmp(p, "early", 5) == 0) {
3792 		/* just "xmon" is equivalent to "xmon=early" */
3793 		xmon_init(1);
3794 		xmon_early = 1;
3795 		xmon_on = 1;
3796 	} else if (strncmp(p, "on", 2) == 0) {
3797 		xmon_init(1);
3798 		xmon_on = 1;
3799 	} else if (strncmp(p, "off", 3) == 0)
3800 		xmon_on = 0;
3801 	else
3802 		return 1;
3803 
3804 	return 0;
3805 }
3806 early_param("xmon", early_parse_xmon);
3807 
3808 void __init xmon_setup(void)
3809 {
3810 	if (xmon_on)
3811 		xmon_init(1);
3812 	if (xmon_early)
3813 		debugger(NULL);
3814 }
3815 
3816 #ifdef CONFIG_SPU_BASE
3817 
3818 struct spu_info {
3819 	struct spu *spu;
3820 	u64 saved_mfc_sr1_RW;
3821 	u32 saved_spu_runcntl_RW;
3822 	unsigned long dump_addr;
3823 	u8 stopped_ok;
3824 };
3825 
3826 #define XMON_NUM_SPUS	16	/* Enough for current hardware */
3827 
3828 static struct spu_info spu_info[XMON_NUM_SPUS];
3829 
3830 void xmon_register_spus(struct list_head *list)
3831 {
3832 	struct spu *spu;
3833 
3834 	list_for_each_entry(spu, list, full_list) {
3835 		if (spu->number >= XMON_NUM_SPUS) {
3836 			WARN_ON(1);
3837 			continue;
3838 		}
3839 
3840 		spu_info[spu->number].spu = spu;
3841 		spu_info[spu->number].stopped_ok = 0;
3842 		spu_info[spu->number].dump_addr = (unsigned long)
3843 				spu_info[spu->number].spu->local_store;
3844 	}
3845 }
3846 
3847 static void stop_spus(void)
3848 {
3849 	struct spu *spu;
3850 	int i;
3851 	u64 tmp;
3852 
3853 	for (i = 0; i < XMON_NUM_SPUS; i++) {
3854 		if (!spu_info[i].spu)
3855 			continue;
3856 
3857 		if (setjmp(bus_error_jmp) == 0) {
3858 			catch_memory_errors = 1;
3859 			sync();
3860 
3861 			spu = spu_info[i].spu;
3862 
3863 			spu_info[i].saved_spu_runcntl_RW =
3864 				in_be32(&spu->problem->spu_runcntl_RW);
3865 
3866 			tmp = spu_mfc_sr1_get(spu);
3867 			spu_info[i].saved_mfc_sr1_RW = tmp;
3868 
3869 			tmp &= ~MFC_STATE1_MASTER_RUN_CONTROL_MASK;
3870 			spu_mfc_sr1_set(spu, tmp);
3871 
3872 			sync();
3873 			__delay(200);
3874 
3875 			spu_info[i].stopped_ok = 1;
3876 
3877 			printf("Stopped spu %.2d (was %s)\n", i,
3878 					spu_info[i].saved_spu_runcntl_RW ?
3879 					"running" : "stopped");
3880 		} else {
3881 			catch_memory_errors = 0;
3882 			printf("*** Error stopping spu %.2d\n", i);
3883 		}
3884 		catch_memory_errors = 0;
3885 	}
3886 }
3887 
3888 static void restart_spus(void)
3889 {
3890 	struct spu *spu;
3891 	int i;
3892 
3893 	for (i = 0; i < XMON_NUM_SPUS; i++) {
3894 		if (!spu_info[i].spu)
3895 			continue;
3896 
3897 		if (!spu_info[i].stopped_ok) {
3898 			printf("*** Error, spu %d was not successfully stopped"
3899 					", not restarting\n", i);
3900 			continue;
3901 		}
3902 
3903 		if (setjmp(bus_error_jmp) == 0) {
3904 			catch_memory_errors = 1;
3905 			sync();
3906 
3907 			spu = spu_info[i].spu;
3908 			spu_mfc_sr1_set(spu, spu_info[i].saved_mfc_sr1_RW);
3909 			out_be32(&spu->problem->spu_runcntl_RW,
3910 					spu_info[i].saved_spu_runcntl_RW);
3911 
3912 			sync();
3913 			__delay(200);
3914 
3915 			printf("Restarted spu %.2d\n", i);
3916 		} else {
3917 			catch_memory_errors = 0;
3918 			printf("*** Error restarting spu %.2d\n", i);
3919 		}
3920 		catch_memory_errors = 0;
3921 	}
3922 }
3923 
3924 #define DUMP_WIDTH	23
3925 #define DUMP_VALUE(format, field, value)				\
3926 do {									\
3927 	if (setjmp(bus_error_jmp) == 0) {				\
3928 		catch_memory_errors = 1;				\
3929 		sync();							\
3930 		printf("  %-*s = "format"\n", DUMP_WIDTH,		\
3931 				#field, value);				\
3932 		sync();							\
3933 		__delay(200);						\
3934 	} else {							\
3935 		catch_memory_errors = 0;				\
3936 		printf("  %-*s = *** Error reading field.\n",		\
3937 					DUMP_WIDTH, #field);		\
3938 	}								\
3939 	catch_memory_errors = 0;					\
3940 } while (0)
3941 
3942 #define DUMP_FIELD(obj, format, field)	\
3943 	DUMP_VALUE(format, field, obj->field)
3944 
3945 static void dump_spu_fields(struct spu *spu)
3946 {
3947 	printf("Dumping spu fields at address %p:\n", spu);
3948 
3949 	DUMP_FIELD(spu, "0x%x", number);
3950 	DUMP_FIELD(spu, "%s", name);
3951 	DUMP_FIELD(spu, "0x%lx", local_store_phys);
3952 	DUMP_FIELD(spu, "0x%p", local_store);
3953 	DUMP_FIELD(spu, "0x%lx", ls_size);
3954 	DUMP_FIELD(spu, "0x%x", node);
3955 	DUMP_FIELD(spu, "0x%lx", flags);
3956 	DUMP_FIELD(spu, "%llu", class_0_pending);
3957 	DUMP_FIELD(spu, "0x%llx", class_0_dar);
3958 	DUMP_FIELD(spu, "0x%llx", class_1_dar);
3959 	DUMP_FIELD(spu, "0x%llx", class_1_dsisr);
3960 	DUMP_FIELD(spu, "0x%x", irqs[0]);
3961 	DUMP_FIELD(spu, "0x%x", irqs[1]);
3962 	DUMP_FIELD(spu, "0x%x", irqs[2]);
3963 	DUMP_FIELD(spu, "0x%x", slb_replace);
3964 	DUMP_FIELD(spu, "%d", pid);
3965 	DUMP_FIELD(spu, "0x%p", mm);
3966 	DUMP_FIELD(spu, "0x%p", ctx);
3967 	DUMP_FIELD(spu, "0x%p", rq);
3968 	DUMP_FIELD(spu, "0x%llx", timestamp);
3969 	DUMP_FIELD(spu, "0x%lx", problem_phys);
3970 	DUMP_FIELD(spu, "0x%p", problem);
3971 	DUMP_VALUE("0x%x", problem->spu_runcntl_RW,
3972 			in_be32(&spu->problem->spu_runcntl_RW));
3973 	DUMP_VALUE("0x%x", problem->spu_status_R,
3974 			in_be32(&spu->problem->spu_status_R));
3975 	DUMP_VALUE("0x%x", problem->spu_npc_RW,
3976 			in_be32(&spu->problem->spu_npc_RW));
3977 	DUMP_FIELD(spu, "0x%p", priv2);
3978 	DUMP_FIELD(spu, "0x%p", pdata);
3979 }
3980 
3981 int
3982 spu_inst_dump(unsigned long adr, long count, int praddr)
3983 {
3984 	return generic_inst_dump(adr, count, praddr, print_insn_spu);
3985 }
3986 
3987 static void dump_spu_ls(unsigned long num, int subcmd)
3988 {
3989 	unsigned long offset, addr, ls_addr;
3990 
3991 	if (setjmp(bus_error_jmp) == 0) {
3992 		catch_memory_errors = 1;
3993 		sync();
3994 		ls_addr = (unsigned long)spu_info[num].spu->local_store;
3995 		sync();
3996 		__delay(200);
3997 	} else {
3998 		catch_memory_errors = 0;
3999 		printf("*** Error: accessing spu info for spu %ld\n", num);
4000 		return;
4001 	}
4002 	catch_memory_errors = 0;
4003 
4004 	if (scanhex(&offset))
4005 		addr = ls_addr + offset;
4006 	else
4007 		addr = spu_info[num].dump_addr;
4008 
4009 	if (addr >= ls_addr + LS_SIZE) {
4010 		printf("*** Error: address outside of local store\n");
4011 		return;
4012 	}
4013 
4014 	switch (subcmd) {
4015 	case 'i':
4016 		addr += spu_inst_dump(addr, 16, 1);
4017 		last_cmd = "sdi\n";
4018 		break;
4019 	default:
4020 		prdump(addr, 64);
4021 		addr += 64;
4022 		last_cmd = "sd\n";
4023 		break;
4024 	}
4025 
4026 	spu_info[num].dump_addr = addr;
4027 }
4028 
4029 static int do_spu_cmd(void)
4030 {
4031 	static unsigned long num = 0;
4032 	int cmd, subcmd = 0;
4033 
4034 	cmd = inchar();
4035 	switch (cmd) {
4036 	case 's':
4037 		stop_spus();
4038 		break;
4039 	case 'r':
4040 		restart_spus();
4041 		break;
4042 	case 'd':
4043 		subcmd = inchar();
4044 		if (isxdigit(subcmd) || subcmd == '\n')
4045 			termch = subcmd;
4046 		/* fall through */
4047 	case 'f':
4048 		scanhex(&num);
4049 		if (num >= XMON_NUM_SPUS || !spu_info[num].spu) {
4050 			printf("*** Error: invalid spu number\n");
4051 			return 0;
4052 		}
4053 
4054 		switch (cmd) {
4055 		case 'f':
4056 			dump_spu_fields(spu_info[num].spu);
4057 			break;
4058 		default:
4059 			dump_spu_ls(num, subcmd);
4060 			break;
4061 		}
4062 
4063 		break;
4064 	default:
4065 		return -1;
4066 	}
4067 
4068 	return 0;
4069 }
4070 #else /* ! CONFIG_SPU_BASE */
4071 static int do_spu_cmd(void)
4072 {
4073 	return -1;
4074 }
4075 #endif
4076