xref: /openbmc/linux/arch/powerpc/xmon/xmon.c (revision dff03381)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Routines providing a simple monitor for use on the PowerMac.
4  *
5  * Copyright (C) 1996-2005 Paul Mackerras.
6  * Copyright (C) 2001 PPC64 Team, IBM Corp
7  * Copyrignt (C) 2006 Michael Ellerman, IBM Corp
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/errno.h>
12 #include <linux/sched/signal.h>
13 #include <linux/smp.h>
14 #include <linux/mm.h>
15 #include <linux/reboot.h>
16 #include <linux/delay.h>
17 #include <linux/kallsyms.h>
18 #include <linux/kmsg_dump.h>
19 #include <linux/cpumask.h>
20 #include <linux/export.h>
21 #include <linux/sysrq.h>
22 #include <linux/interrupt.h>
23 #include <linux/irq.h>
24 #include <linux/bug.h>
25 #include <linux/nmi.h>
26 #include <linux/ctype.h>
27 #include <linux/highmem.h>
28 #include <linux/security.h>
29 #include <linux/debugfs.h>
30 
31 #include <asm/ptrace.h>
32 #include <asm/smp.h>
33 #include <asm/string.h>
34 #include <asm/machdep.h>
35 #include <asm/xmon.h>
36 #include <asm/processor.h>
37 #include <asm/mmu.h>
38 #include <asm/mmu_context.h>
39 #include <asm/plpar_wrappers.h>
40 #include <asm/cputable.h>
41 #include <asm/rtas.h>
42 #include <asm/sstep.h>
43 #include <asm/irq_regs.h>
44 #include <asm/spu.h>
45 #include <asm/spu_priv1.h>
46 #include <asm/setjmp.h>
47 #include <asm/reg.h>
48 #include <asm/debug.h>
49 #include <asm/hw_breakpoint.h>
50 #include <asm/xive.h>
51 #include <asm/opal.h>
52 #include <asm/firmware.h>
53 #include <asm/code-patching.h>
54 #include <asm/sections.h>
55 #include <asm/inst.h>
56 #include <asm/interrupt.h>
57 
58 #ifdef CONFIG_PPC64
59 #include <asm/hvcall.h>
60 #include <asm/paca.h>
61 #endif
62 
63 #include "nonstdio.h"
64 #include "dis-asm.h"
65 #include "xmon_bpts.h"
66 
67 #ifdef CONFIG_SMP
68 static cpumask_t cpus_in_xmon = CPU_MASK_NONE;
69 static unsigned long xmon_taken = 1;
70 static int xmon_owner;
71 static int xmon_gate;
72 static int xmon_batch;
73 static unsigned long xmon_batch_start_cpu;
74 static cpumask_t xmon_batch_cpus = CPU_MASK_NONE;
75 #else
76 #define xmon_owner 0
77 #endif /* CONFIG_SMP */
78 
79 #ifdef CONFIG_PPC_PSERIES
80 static int set_indicator_token = RTAS_UNKNOWN_SERVICE;
81 #endif
82 static unsigned long in_xmon __read_mostly = 0;
83 static int xmon_on = IS_ENABLED(CONFIG_XMON_DEFAULT);
84 static bool xmon_is_ro = IS_ENABLED(CONFIG_XMON_DEFAULT_RO_MODE);
85 
86 static unsigned long adrs;
87 static int size = 1;
88 #define MAX_DUMP (64 * 1024)
89 static unsigned long ndump = 64;
90 #define MAX_IDUMP (MAX_DUMP >> 2)
91 static unsigned long nidump = 16;
92 static unsigned long ncsum = 4096;
93 static int termch;
94 static char tmpstr[128];
95 static int tracing_enabled;
96 
97 static long bus_error_jmp[JMP_BUF_LEN];
98 static int catch_memory_errors;
99 static int catch_spr_faults;
100 static long *xmon_fault_jmp[NR_CPUS];
101 
102 /* Breakpoint stuff */
103 struct bpt {
104 	unsigned long	address;
105 	u32		*instr;
106 	atomic_t	ref_count;
107 	int		enabled;
108 	unsigned long	pad;
109 };
110 
111 /* Bits in bpt.enabled */
112 #define BP_CIABR	1
113 #define BP_TRAP		2
114 #define BP_DABR		4
115 
116 static struct bpt bpts[NBPTS];
117 static struct bpt dabr[HBP_NUM_MAX];
118 static struct bpt *iabr;
119 static unsigned int bpinstr = PPC_RAW_TRAP();
120 
121 #define BP_NUM(bp)	((bp) - bpts + 1)
122 
123 /* Prototypes */
124 static int cmds(struct pt_regs *);
125 static int mread(unsigned long, void *, int);
126 static int mwrite(unsigned long, void *, int);
127 static int mread_instr(unsigned long, ppc_inst_t *);
128 static int handle_fault(struct pt_regs *);
129 static void byterev(unsigned char *, int);
130 static void memex(void);
131 static int bsesc(void);
132 static void dump(void);
133 static void show_pte(unsigned long);
134 static void prdump(unsigned long, long);
135 static int ppc_inst_dump(unsigned long, long, int);
136 static void dump_log_buf(void);
137 
138 #ifdef CONFIG_SMP
139 static int xmon_switch_cpu(unsigned long);
140 static int xmon_batch_next_cpu(void);
141 static int batch_cmds(struct pt_regs *);
142 #endif
143 
144 #ifdef CONFIG_PPC_POWERNV
145 static void dump_opal_msglog(void);
146 #else
147 static inline void dump_opal_msglog(void)
148 {
149 	printf("Machine is not running OPAL firmware.\n");
150 }
151 #endif
152 
153 static void backtrace(struct pt_regs *);
154 static void excprint(struct pt_regs *);
155 static void prregs(struct pt_regs *);
156 static void memops(int);
157 static void memlocate(void);
158 static void memzcan(void);
159 static void memdiffs(unsigned char *, unsigned char *, unsigned, unsigned);
160 int skipbl(void);
161 int scanhex(unsigned long *valp);
162 static void scannl(void);
163 static int hexdigit(int);
164 void getstring(char *, int);
165 static void flush_input(void);
166 static int inchar(void);
167 static void take_input(char *);
168 static int  read_spr(int, unsigned long *);
169 static void write_spr(int, unsigned long);
170 static void super_regs(void);
171 static void remove_bpts(void);
172 static void insert_bpts(void);
173 static void remove_cpu_bpts(void);
174 static void insert_cpu_bpts(void);
175 static struct bpt *at_breakpoint(unsigned long pc);
176 static struct bpt *in_breakpoint_table(unsigned long pc, unsigned long *offp);
177 static int  do_step(struct pt_regs *);
178 static void bpt_cmds(void);
179 static void cacheflush(void);
180 static int  cpu_cmd(void);
181 static void csum(void);
182 static void bootcmds(void);
183 static void proccall(void);
184 static void show_tasks(void);
185 void dump_segments(void);
186 static void symbol_lookup(void);
187 static void xmon_show_stack(unsigned long sp, unsigned long lr,
188 			    unsigned long pc);
189 static void xmon_print_symbol(unsigned long address, const char *mid,
190 			      const char *after);
191 static const char *getvecname(unsigned long vec);
192 
193 static int do_spu_cmd(void);
194 
195 #ifdef CONFIG_44x
196 static void dump_tlb_44x(void);
197 #endif
198 #ifdef CONFIG_PPC_BOOK3E
199 static void dump_tlb_book3e(void);
200 #endif
201 
202 static void clear_all_bpt(void);
203 
204 #ifdef CONFIG_PPC64
205 #define REG		"%.16lx"
206 #else
207 #define REG		"%.8lx"
208 #endif
209 
210 #ifdef __LITTLE_ENDIAN__
211 #define GETWORD(v)	(((v)[3] << 24) + ((v)[2] << 16) + ((v)[1] << 8) + (v)[0])
212 #else
213 #define GETWORD(v)	(((v)[0] << 24) + ((v)[1] << 16) + ((v)[2] << 8) + (v)[3])
214 #endif
215 
216 static const char *xmon_ro_msg = "Operation disabled: xmon in read-only mode\n";
217 
218 static char *help_string = "\
219 Commands:\n\
220   b	show breakpoints\n\
221   bd	set data breakpoint\n\
222   bi	set instruction breakpoint\n\
223   bc	clear breakpoint\n"
224 #ifdef CONFIG_SMP
225   "\
226   c	print cpus stopped in xmon\n\
227   c#	try to switch to cpu number h (in hex)\n\
228   c# $	run command '$' (one of 'r','S' or 't') on all cpus in xmon\n"
229 #endif
230   "\
231   C	checksum\n\
232   d	dump bytes\n\
233   d1	dump 1 byte values\n\
234   d2	dump 2 byte values\n\
235   d4	dump 4 byte values\n\
236   d8	dump 8 byte values\n\
237   di	dump instructions\n\
238   df	dump float values\n\
239   dd	dump double values\n\
240   dl    dump the kernel log buffer\n"
241 #ifdef CONFIG_PPC_POWERNV
242   "\
243   do    dump the OPAL message log\n"
244 #endif
245 #ifdef CONFIG_PPC64
246   "\
247   dp[#]	dump paca for current cpu, or cpu #\n\
248   dpa	dump paca for all possible cpus\n"
249 #endif
250   "\
251   dr	dump stream of raw bytes\n\
252   dv	dump virtual address translation \n\
253   dt	dump the tracing buffers (uses printk)\n\
254   dtc	dump the tracing buffers for current CPU (uses printk)\n\
255 "
256 #ifdef CONFIG_PPC_POWERNV
257 "  dx#   dump xive on CPU #\n\
258   dxi#  dump xive irq state #\n\
259   dxa   dump xive on all CPUs\n"
260 #endif
261 "  e	print exception information\n\
262   f	flush cache\n\
263   la	lookup symbol+offset of specified address\n\
264   ls	lookup address of specified symbol\n\
265   lp s [#]	lookup address of percpu symbol s for current cpu, or cpu #\n\
266   m	examine/change memory\n\
267   mm	move a block of memory\n\
268   ms	set a block of memory\n\
269   md	compare two blocks of memory\n\
270   ml	locate a block of memory\n\
271   mz	zero a block of memory\n\
272   mi	show information about memory allocation\n\
273   p 	call a procedure\n\
274   P 	list processes/tasks\n\
275   r	print registers\n\
276   s	single step\n"
277 #ifdef CONFIG_SPU_BASE
278 "  ss	stop execution on all spus\n\
279   sr	restore execution on stopped spus\n\
280   sf  #	dump spu fields for spu # (in hex)\n\
281   sd  #	dump spu local store for spu # (in hex)\n\
282   sdi #	disassemble spu local store for spu # (in hex)\n"
283 #endif
284 "  S	print special registers\n\
285   Sa    print all SPRs\n\
286   Sr #	read SPR #\n\
287   Sw #v write v to SPR #\n\
288   t	print backtrace\n\
289   x	exit monitor and recover\n\
290   X	exit monitor and don't recover\n"
291 #if defined(CONFIG_PPC64) && !defined(CONFIG_PPC_BOOK3E)
292 "  u	dump segment table or SLB\n"
293 #elif defined(CONFIG_PPC_BOOK3S_32)
294 "  u	dump segment registers\n"
295 #elif defined(CONFIG_44x) || defined(CONFIG_PPC_BOOK3E)
296 "  u	dump TLB\n"
297 #endif
298 "  U	show uptime information\n"
299 "  ?	help\n"
300 "  # n	limit output to n lines per page (for dp, dpa, dl)\n"
301 "  zr	reboot\n"
302 "  zh	halt\n"
303 ;
304 
305 #ifdef CONFIG_SECURITY
306 static bool xmon_is_locked_down(void)
307 {
308 	static bool lockdown;
309 
310 	if (!lockdown) {
311 		lockdown = !!security_locked_down(LOCKDOWN_XMON_RW);
312 		if (lockdown) {
313 			printf("xmon: Disabled due to kernel lockdown\n");
314 			xmon_is_ro = true;
315 		}
316 	}
317 
318 	if (!xmon_is_ro) {
319 		xmon_is_ro = !!security_locked_down(LOCKDOWN_XMON_WR);
320 		if (xmon_is_ro)
321 			printf("xmon: Read-only due to kernel lockdown\n");
322 	}
323 
324 	return lockdown;
325 }
326 #else /* CONFIG_SECURITY */
327 static inline bool xmon_is_locked_down(void)
328 {
329 	return false;
330 }
331 #endif
332 
333 static struct pt_regs *xmon_regs;
334 
335 static inline void sync(void)
336 {
337 	asm volatile("sync; isync");
338 }
339 
340 static inline void cflush(void *p)
341 {
342 	asm volatile ("dcbf 0,%0; icbi 0,%0" : : "r" (p));
343 }
344 
345 static inline void cinval(void *p)
346 {
347 	asm volatile ("dcbi 0,%0; icbi 0,%0" : : "r" (p));
348 }
349 
350 /**
351  * write_ciabr() - write the CIABR SPR
352  * @ciabr:	The value to write.
353  *
354  * This function writes a value to the CIARB register either directly
355  * through mtspr instruction if the kernel is in HV privilege mode or
356  * call a hypervisor function to achieve the same in case the kernel
357  * is in supervisor privilege mode.
358  */
359 static void write_ciabr(unsigned long ciabr)
360 {
361 	if (!cpu_has_feature(CPU_FTR_ARCH_207S))
362 		return;
363 
364 	if (cpu_has_feature(CPU_FTR_HVMODE)) {
365 		mtspr(SPRN_CIABR, ciabr);
366 		return;
367 	}
368 	plpar_set_ciabr(ciabr);
369 }
370 
371 /**
372  * set_ciabr() - set the CIABR
373  * @addr:	The value to set.
374  *
375  * This function sets the correct privilege value into the HW
376  * breakpoint address before writing it up in the CIABR register.
377  */
378 static void set_ciabr(unsigned long addr)
379 {
380 	addr &= ~CIABR_PRIV;
381 
382 	if (cpu_has_feature(CPU_FTR_HVMODE))
383 		addr |= CIABR_PRIV_HYPER;
384 	else
385 		addr |= CIABR_PRIV_SUPER;
386 	write_ciabr(addr);
387 }
388 
389 /*
390  * Disable surveillance (the service processor watchdog function)
391  * while we are in xmon.
392  * XXX we should re-enable it when we leave. :)
393  */
394 #define SURVEILLANCE_TOKEN	9000
395 
396 static inline void disable_surveillance(void)
397 {
398 #ifdef CONFIG_PPC_PSERIES
399 	/* Since this can't be a module, args should end up below 4GB. */
400 	static struct rtas_args args;
401 
402 	/*
403 	 * At this point we have got all the cpus we can into
404 	 * xmon, so there is hopefully no other cpu calling RTAS
405 	 * at the moment, even though we don't take rtas.lock.
406 	 * If we did try to take rtas.lock there would be a
407 	 * real possibility of deadlock.
408 	 */
409 	if (set_indicator_token == RTAS_UNKNOWN_SERVICE)
410 		return;
411 
412 	rtas_call_unlocked(&args, set_indicator_token, 3, 1, NULL,
413 			   SURVEILLANCE_TOKEN, 0, 0);
414 
415 #endif /* CONFIG_PPC_PSERIES */
416 }
417 
418 #ifdef CONFIG_SMP
419 static int xmon_speaker;
420 
421 static void get_output_lock(void)
422 {
423 	int me = smp_processor_id() + 0x100;
424 	int last_speaker = 0, prev;
425 	long timeout;
426 
427 	if (xmon_speaker == me)
428 		return;
429 
430 	for (;;) {
431 		last_speaker = cmpxchg(&xmon_speaker, 0, me);
432 		if (last_speaker == 0)
433 			return;
434 
435 		/*
436 		 * Wait a full second for the lock, we might be on a slow
437 		 * console, but check every 100us.
438 		 */
439 		timeout = 10000;
440 		while (xmon_speaker == last_speaker) {
441 			if (--timeout > 0) {
442 				udelay(100);
443 				continue;
444 			}
445 
446 			/* hostile takeover */
447 			prev = cmpxchg(&xmon_speaker, last_speaker, me);
448 			if (prev == last_speaker)
449 				return;
450 			break;
451 		}
452 	}
453 }
454 
455 static void release_output_lock(void)
456 {
457 	xmon_speaker = 0;
458 }
459 
460 int cpus_are_in_xmon(void)
461 {
462 	return !cpumask_empty(&cpus_in_xmon);
463 }
464 
465 static bool wait_for_other_cpus(int ncpus)
466 {
467 	unsigned long timeout;
468 
469 	/* We wait for 2s, which is a metric "little while" */
470 	for (timeout = 20000; timeout != 0; --timeout) {
471 		if (cpumask_weight(&cpus_in_xmon) >= ncpus)
472 			return true;
473 		udelay(100);
474 		barrier();
475 	}
476 
477 	return false;
478 }
479 #else /* CONFIG_SMP */
480 static inline void get_output_lock(void) {}
481 static inline void release_output_lock(void) {}
482 #endif
483 
484 static void xmon_touch_watchdogs(void)
485 {
486 	touch_softlockup_watchdog_sync();
487 	rcu_cpu_stall_reset();
488 	touch_nmi_watchdog();
489 }
490 
491 static int xmon_core(struct pt_regs *regs, volatile int fromipi)
492 {
493 	volatile int cmd = 0;
494 	struct bpt *volatile bp;
495 	long recurse_jmp[JMP_BUF_LEN];
496 	bool locked_down;
497 	unsigned long offset;
498 	unsigned long flags;
499 #ifdef CONFIG_SMP
500 	int cpu;
501 	int secondary;
502 #endif
503 
504 	local_irq_save(flags);
505 	hard_irq_disable();
506 
507 	locked_down = xmon_is_locked_down();
508 
509 	if (!fromipi) {
510 		tracing_enabled = tracing_is_on();
511 		tracing_off();
512 	}
513 
514 	bp = in_breakpoint_table(regs->nip, &offset);
515 	if (bp != NULL) {
516 		regs_set_return_ip(regs, bp->address + offset);
517 		atomic_dec(&bp->ref_count);
518 	}
519 
520 	remove_cpu_bpts();
521 
522 #ifdef CONFIG_SMP
523 	cpu = smp_processor_id();
524 	if (cpumask_test_cpu(cpu, &cpus_in_xmon)) {
525 		/*
526 		 * We catch SPR read/write faults here because the 0x700, 0xf60
527 		 * etc. handlers don't call debugger_fault_handler().
528 		 */
529 		if (catch_spr_faults)
530 			longjmp(bus_error_jmp, 1);
531 		get_output_lock();
532 		excprint(regs);
533 		printf("cpu 0x%x: Exception %lx %s in xmon, "
534 		       "returning to main loop\n",
535 		       cpu, regs->trap, getvecname(TRAP(regs)));
536 		release_output_lock();
537 		longjmp(xmon_fault_jmp[cpu], 1);
538 	}
539 
540 	if (setjmp(recurse_jmp) != 0) {
541 		if (!in_xmon || !xmon_gate) {
542 			get_output_lock();
543 			printf("xmon: WARNING: bad recursive fault "
544 			       "on cpu 0x%x\n", cpu);
545 			release_output_lock();
546 			goto waiting;
547 		}
548 		secondary = !(xmon_taken && cpu == xmon_owner);
549 		goto cmdloop;
550 	}
551 
552 	xmon_fault_jmp[cpu] = recurse_jmp;
553 
554 	bp = NULL;
555 	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) == (MSR_IR|MSR_64BIT))
556 		bp = at_breakpoint(regs->nip);
557 	if (bp || regs_is_unrecoverable(regs))
558 		fromipi = 0;
559 
560 	if (!fromipi) {
561 		get_output_lock();
562 		if (!locked_down)
563 			excprint(regs);
564 		if (bp) {
565 			printf("cpu 0x%x stopped at breakpoint 0x%tx (",
566 			       cpu, BP_NUM(bp));
567 			xmon_print_symbol(regs->nip, " ", ")\n");
568 		}
569 		if (regs_is_unrecoverable(regs))
570 			printf("WARNING: exception is not recoverable, "
571 			       "can't continue\n");
572 		release_output_lock();
573 	}
574 
575 	cpumask_set_cpu(cpu, &cpus_in_xmon);
576 
577  waiting:
578 	secondary = 1;
579 	spin_begin();
580 	while (secondary && !xmon_gate) {
581 		if (in_xmon == 0) {
582 			if (fromipi) {
583 				spin_end();
584 				goto leave;
585 			}
586 			secondary = test_and_set_bit(0, &in_xmon);
587 		}
588 		spin_cpu_relax();
589 		touch_nmi_watchdog();
590 	}
591 	spin_end();
592 
593 	if (!secondary && !xmon_gate) {
594 		/* we are the first cpu to come in */
595 		/* interrupt other cpu(s) */
596 		int ncpus = num_online_cpus();
597 
598 		xmon_owner = cpu;
599 		mb();
600 		if (ncpus > 1) {
601 			/*
602 			 * A system reset (trap == 0x100) can be triggered on
603 			 * all CPUs, so when we come in via 0x100 try waiting
604 			 * for the other CPUs to come in before we send the
605 			 * debugger break (IPI). This is similar to
606 			 * crash_kexec_secondary().
607 			 */
608 			if (TRAP(regs) !=  INTERRUPT_SYSTEM_RESET || !wait_for_other_cpus(ncpus))
609 				smp_send_debugger_break();
610 
611 			wait_for_other_cpus(ncpus);
612 		}
613 		remove_bpts();
614 		disable_surveillance();
615 
616 		if (!locked_down) {
617 			/* for breakpoint or single step, print curr insn */
618 			if (bp || TRAP(regs) == INTERRUPT_TRACE)
619 				ppc_inst_dump(regs->nip, 1, 0);
620 			printf("enter ? for help\n");
621 		}
622 
623 		mb();
624 		xmon_gate = 1;
625 		barrier();
626 		touch_nmi_watchdog();
627 	}
628 
629  cmdloop:
630 	while (in_xmon) {
631 		if (secondary) {
632 			spin_begin();
633 			if (cpu == xmon_owner) {
634 				if (!test_and_set_bit(0, &xmon_taken)) {
635 					secondary = 0;
636 					spin_end();
637 					continue;
638 				}
639 				/* missed it */
640 				while (cpu == xmon_owner)
641 					spin_cpu_relax();
642 			}
643 			spin_cpu_relax();
644 			touch_nmi_watchdog();
645 		} else {
646 			cmd = 1;
647 #ifdef CONFIG_SMP
648 			if (xmon_batch)
649 				cmd = batch_cmds(regs);
650 #endif
651 			if (!locked_down && cmd)
652 				cmd = cmds(regs);
653 			if (locked_down || cmd != 0) {
654 				/* exiting xmon */
655 				insert_bpts();
656 				xmon_gate = 0;
657 				wmb();
658 				in_xmon = 0;
659 				break;
660 			}
661 			/* have switched to some other cpu */
662 			secondary = 1;
663 		}
664 	}
665  leave:
666 	cpumask_clear_cpu(cpu, &cpus_in_xmon);
667 	xmon_fault_jmp[cpu] = NULL;
668 #else
669 	/* UP is simple... */
670 	if (in_xmon) {
671 		printf("Exception %lx %s in xmon, returning to main loop\n",
672 		       regs->trap, getvecname(TRAP(regs)));
673 		longjmp(xmon_fault_jmp[0], 1);
674 	}
675 	if (setjmp(recurse_jmp) == 0) {
676 		xmon_fault_jmp[0] = recurse_jmp;
677 		in_xmon = 1;
678 
679 		excprint(regs);
680 		bp = at_breakpoint(regs->nip);
681 		if (bp) {
682 			printf("Stopped at breakpoint %tx (", BP_NUM(bp));
683 			xmon_print_symbol(regs->nip, " ", ")\n");
684 		}
685 		if (regs_is_unrecoverable(regs))
686 			printf("WARNING: exception is not recoverable, "
687 			       "can't continue\n");
688 		remove_bpts();
689 		disable_surveillance();
690 		if (!locked_down) {
691 			/* for breakpoint or single step, print current insn */
692 			if (bp || TRAP(regs) == INTERRUPT_TRACE)
693 				ppc_inst_dump(regs->nip, 1, 0);
694 			printf("enter ? for help\n");
695 		}
696 	}
697 
698 	if (!locked_down)
699 		cmd = cmds(regs);
700 
701 	insert_bpts();
702 	in_xmon = 0;
703 #endif
704 
705 #ifdef CONFIG_BOOKE
706 	if (regs->msr & MSR_DE) {
707 		bp = at_breakpoint(regs->nip);
708 		if (bp != NULL) {
709 			regs_set_return_ip(regs, (unsigned long) &bp->instr[0]);
710 			atomic_inc(&bp->ref_count);
711 		}
712 	}
713 #else
714 	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) == (MSR_IR|MSR_64BIT)) {
715 		bp = at_breakpoint(regs->nip);
716 		if (bp != NULL) {
717 			int stepped = emulate_step(regs, ppc_inst_read(bp->instr));
718 			if (stepped == 0) {
719 				regs_set_return_ip(regs, (unsigned long) &bp->instr[0]);
720 				atomic_inc(&bp->ref_count);
721 			} else if (stepped < 0) {
722 				printf("Couldn't single-step %s instruction\n",
723 				    IS_RFID(ppc_inst_read(bp->instr))? "rfid": "mtmsrd");
724 			}
725 		}
726 	}
727 #endif
728 	if (locked_down)
729 		clear_all_bpt();
730 	else
731 		insert_cpu_bpts();
732 
733 	xmon_touch_watchdogs();
734 	local_irq_restore(flags);
735 
736 	return cmd != 'X' && cmd != EOF;
737 }
738 
739 int xmon(struct pt_regs *excp)
740 {
741 	struct pt_regs regs;
742 
743 	if (excp == NULL) {
744 		ppc_save_regs(&regs);
745 		excp = &regs;
746 	}
747 
748 	return xmon_core(excp, 0);
749 }
750 EXPORT_SYMBOL(xmon);
751 
752 irqreturn_t xmon_irq(int irq, void *d)
753 {
754 	unsigned long flags;
755 	local_irq_save(flags);
756 	printf("Keyboard interrupt\n");
757 	xmon(get_irq_regs());
758 	local_irq_restore(flags);
759 	return IRQ_HANDLED;
760 }
761 
762 static int xmon_bpt(struct pt_regs *regs)
763 {
764 	struct bpt *bp;
765 	unsigned long offset;
766 
767 	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) != (MSR_IR|MSR_64BIT))
768 		return 0;
769 
770 	/* Are we at the trap at bp->instr[1] for some bp? */
771 	bp = in_breakpoint_table(regs->nip, &offset);
772 	if (bp != NULL && (offset == 4 || offset == 8)) {
773 		regs_set_return_ip(regs, bp->address + offset);
774 		atomic_dec(&bp->ref_count);
775 		return 1;
776 	}
777 
778 	/* Are we at a breakpoint? */
779 	bp = at_breakpoint(regs->nip);
780 	if (!bp)
781 		return 0;
782 
783 	xmon_core(regs, 0);
784 
785 	return 1;
786 }
787 
788 static int xmon_sstep(struct pt_regs *regs)
789 {
790 	if (user_mode(regs))
791 		return 0;
792 	xmon_core(regs, 0);
793 	return 1;
794 }
795 
796 static int xmon_break_match(struct pt_regs *regs)
797 {
798 	int i;
799 
800 	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) != (MSR_IR|MSR_64BIT))
801 		return 0;
802 	for (i = 0; i < nr_wp_slots(); i++) {
803 		if (dabr[i].enabled)
804 			goto found;
805 	}
806 	return 0;
807 
808 found:
809 	xmon_core(regs, 0);
810 	return 1;
811 }
812 
813 static int xmon_iabr_match(struct pt_regs *regs)
814 {
815 	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) != (MSR_IR|MSR_64BIT))
816 		return 0;
817 	if (iabr == NULL)
818 		return 0;
819 	xmon_core(regs, 0);
820 	return 1;
821 }
822 
823 static int xmon_ipi(struct pt_regs *regs)
824 {
825 #ifdef CONFIG_SMP
826 	if (in_xmon && !cpumask_test_cpu(smp_processor_id(), &cpus_in_xmon))
827 		xmon_core(regs, 1);
828 #endif
829 	return 0;
830 }
831 
832 static int xmon_fault_handler(struct pt_regs *regs)
833 {
834 	struct bpt *bp;
835 	unsigned long offset;
836 
837 	if (in_xmon && catch_memory_errors)
838 		handle_fault(regs);	/* doesn't return */
839 
840 	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) == (MSR_IR|MSR_64BIT)) {
841 		bp = in_breakpoint_table(regs->nip, &offset);
842 		if (bp != NULL) {
843 			regs_set_return_ip(regs, bp->address + offset);
844 			atomic_dec(&bp->ref_count);
845 		}
846 	}
847 
848 	return 0;
849 }
850 
851 /* Force enable xmon if not already enabled */
852 static inline void force_enable_xmon(void)
853 {
854 	/* Enable xmon hooks if needed */
855 	if (!xmon_on) {
856 		printf("xmon: Enabling debugger hooks\n");
857 		xmon_on = 1;
858 	}
859 }
860 
861 static struct bpt *at_breakpoint(unsigned long pc)
862 {
863 	int i;
864 	struct bpt *volatile bp;
865 
866 	bp = bpts;
867 	for (i = 0; i < NBPTS; ++i, ++bp)
868 		if (bp->enabled && pc == bp->address)
869 			return bp;
870 	return NULL;
871 }
872 
873 static struct bpt *in_breakpoint_table(unsigned long nip, unsigned long *offp)
874 {
875 	unsigned long off;
876 
877 	off = nip - (unsigned long)bpt_table;
878 	if (off >= sizeof(bpt_table))
879 		return NULL;
880 	*offp = off & (BPT_SIZE - 1);
881 	if (off & 3)
882 		return NULL;
883 	return bpts + (off / BPT_SIZE);
884 }
885 
886 static struct bpt *new_breakpoint(unsigned long a)
887 {
888 	struct bpt *bp;
889 
890 	a &= ~3UL;
891 	bp = at_breakpoint(a);
892 	if (bp)
893 		return bp;
894 
895 	for (bp = bpts; bp < &bpts[NBPTS]; ++bp) {
896 		if (!bp->enabled && atomic_read(&bp->ref_count) == 0) {
897 			bp->address = a;
898 			bp->instr = (void *)(bpt_table + ((bp - bpts) * BPT_WORDS));
899 			return bp;
900 		}
901 	}
902 
903 	printf("Sorry, no free breakpoints.  Please clear one first.\n");
904 	return NULL;
905 }
906 
907 static void insert_bpts(void)
908 {
909 	int i;
910 	ppc_inst_t instr, instr2;
911 	struct bpt *bp, *bp2;
912 
913 	bp = bpts;
914 	for (i = 0; i < NBPTS; ++i, ++bp) {
915 		if ((bp->enabled & (BP_TRAP|BP_CIABR)) == 0)
916 			continue;
917 		if (!mread_instr(bp->address, &instr)) {
918 			printf("Couldn't read instruction at %lx, "
919 			       "disabling breakpoint there\n", bp->address);
920 			bp->enabled = 0;
921 			continue;
922 		}
923 		if (!can_single_step(ppc_inst_val(instr))) {
924 			printf("Breakpoint at %lx is on an instruction that can't be single stepped, disabling it\n",
925 					bp->address);
926 			bp->enabled = 0;
927 			continue;
928 		}
929 		/*
930 		 * Check the address is not a suffix by looking for a prefix in
931 		 * front of it.
932 		 */
933 		if (mread_instr(bp->address - 4, &instr2) == 8) {
934 			printf("Breakpoint at %lx is on the second word of a prefixed instruction, disabling it\n",
935 			       bp->address);
936 			bp->enabled = 0;
937 			continue;
938 		}
939 		/*
940 		 * We might still be a suffix - if the prefix has already been
941 		 * replaced by a breakpoint we won't catch it with the above
942 		 * test.
943 		 */
944 		bp2 = at_breakpoint(bp->address - 4);
945 		if (bp2 && ppc_inst_prefixed(ppc_inst_read(bp2->instr))) {
946 			printf("Breakpoint at %lx is on the second word of a prefixed instruction, disabling it\n",
947 			       bp->address);
948 			bp->enabled = 0;
949 			continue;
950 		}
951 
952 		patch_instruction(bp->instr, instr);
953 		patch_instruction(ppc_inst_next(bp->instr, bp->instr),
954 				  ppc_inst(bpinstr));
955 		if (bp->enabled & BP_CIABR)
956 			continue;
957 		if (patch_instruction((u32 *)bp->address,
958 				      ppc_inst(bpinstr)) != 0) {
959 			printf("Couldn't write instruction at %lx, "
960 			       "disabling breakpoint there\n", bp->address);
961 			bp->enabled &= ~BP_TRAP;
962 			continue;
963 		}
964 	}
965 }
966 
967 static void insert_cpu_bpts(void)
968 {
969 	int i;
970 	struct arch_hw_breakpoint brk;
971 
972 	for (i = 0; i < nr_wp_slots(); i++) {
973 		if (dabr[i].enabled) {
974 			brk.address = dabr[i].address;
975 			brk.type = (dabr[i].enabled & HW_BRK_TYPE_DABR) | HW_BRK_TYPE_PRIV_ALL;
976 			brk.len = 8;
977 			brk.hw_len = 8;
978 			__set_breakpoint(i, &brk);
979 		}
980 	}
981 
982 	if (iabr)
983 		set_ciabr(iabr->address);
984 }
985 
986 static void remove_bpts(void)
987 {
988 	int i;
989 	struct bpt *bp;
990 	ppc_inst_t instr;
991 
992 	bp = bpts;
993 	for (i = 0; i < NBPTS; ++i, ++bp) {
994 		if ((bp->enabled & (BP_TRAP|BP_CIABR)) != BP_TRAP)
995 			continue;
996 		if (mread_instr(bp->address, &instr)
997 		    && ppc_inst_equal(instr, ppc_inst(bpinstr))
998 		    && patch_instruction(
999 			(u32 *)bp->address, ppc_inst_read(bp->instr)) != 0)
1000 			printf("Couldn't remove breakpoint at %lx\n",
1001 			       bp->address);
1002 	}
1003 }
1004 
1005 static void remove_cpu_bpts(void)
1006 {
1007 	hw_breakpoint_disable();
1008 	write_ciabr(0);
1009 }
1010 
1011 /* Based on uptime_proc_show(). */
1012 static void
1013 show_uptime(void)
1014 {
1015 	struct timespec64 uptime;
1016 
1017 	if (setjmp(bus_error_jmp) == 0) {
1018 		catch_memory_errors = 1;
1019 		sync();
1020 
1021 		ktime_get_coarse_boottime_ts64(&uptime);
1022 		printf("Uptime: %lu.%.2lu seconds\n", (unsigned long)uptime.tv_sec,
1023 			((unsigned long)uptime.tv_nsec / (NSEC_PER_SEC/100)));
1024 
1025 		sync();
1026 		__delay(200);						\
1027 	}
1028 	catch_memory_errors = 0;
1029 }
1030 
1031 static void set_lpp_cmd(void)
1032 {
1033 	unsigned long lpp;
1034 
1035 	if (!scanhex(&lpp)) {
1036 		printf("Invalid number.\n");
1037 		lpp = 0;
1038 	}
1039 	xmon_set_pagination_lpp(lpp);
1040 }
1041 /* Command interpreting routine */
1042 static char *last_cmd;
1043 
1044 static int
1045 cmds(struct pt_regs *excp)
1046 {
1047 	int cmd = 0;
1048 
1049 	last_cmd = NULL;
1050 	xmon_regs = excp;
1051 
1052 	xmon_show_stack(excp->gpr[1], excp->link, excp->nip);
1053 
1054 	for(;;) {
1055 #ifdef CONFIG_SMP
1056 		printf("%x:", smp_processor_id());
1057 #endif /* CONFIG_SMP */
1058 		printf("mon> ");
1059 		flush_input();
1060 		termch = 0;
1061 		cmd = skipbl();
1062 		if( cmd == '\n' ) {
1063 			if (last_cmd == NULL)
1064 				continue;
1065 			take_input(last_cmd);
1066 			last_cmd = NULL;
1067 			cmd = inchar();
1068 		}
1069 		switch (cmd) {
1070 		case 'm':
1071 			cmd = inchar();
1072 			switch (cmd) {
1073 			case 'm':
1074 			case 's':
1075 			case 'd':
1076 				memops(cmd);
1077 				break;
1078 			case 'l':
1079 				memlocate();
1080 				break;
1081 			case 'z':
1082 				if (xmon_is_ro) {
1083 					printf(xmon_ro_msg);
1084 					break;
1085 				}
1086 				memzcan();
1087 				break;
1088 			case 'i':
1089 				show_mem(0, NULL);
1090 				break;
1091 			default:
1092 				termch = cmd;
1093 				memex();
1094 			}
1095 			break;
1096 		case 'd':
1097 			dump();
1098 			break;
1099 		case 'l':
1100 			symbol_lookup();
1101 			break;
1102 		case 'r':
1103 			prregs(excp);	/* print regs */
1104 			break;
1105 		case 'e':
1106 			excprint(excp);
1107 			break;
1108 		case 'S':
1109 			super_regs();
1110 			break;
1111 		case 't':
1112 			backtrace(excp);
1113 			break;
1114 		case 'f':
1115 			cacheflush();
1116 			break;
1117 		case 's':
1118 			if (do_spu_cmd() == 0)
1119 				break;
1120 			if (do_step(excp))
1121 				return cmd;
1122 			break;
1123 		case 'x':
1124 		case 'X':
1125 			if (tracing_enabled)
1126 				tracing_on();
1127 			return cmd;
1128 		case EOF:
1129 			printf(" <no input ...>\n");
1130 			mdelay(2000);
1131 			return cmd;
1132 		case '?':
1133 			xmon_puts(help_string);
1134 			break;
1135 		case '#':
1136 			set_lpp_cmd();
1137 			break;
1138 		case 'b':
1139 			bpt_cmds();
1140 			break;
1141 		case 'C':
1142 			csum();
1143 			break;
1144 		case 'c':
1145 			if (cpu_cmd())
1146 				return 0;
1147 			break;
1148 		case 'z':
1149 			bootcmds();
1150 			break;
1151 		case 'p':
1152 			if (xmon_is_ro) {
1153 				printf(xmon_ro_msg);
1154 				break;
1155 			}
1156 			proccall();
1157 			break;
1158 		case 'P':
1159 			show_tasks();
1160 			break;
1161 #if defined(CONFIG_PPC_BOOK3S_32) || defined(CONFIG_PPC_64S_HASH_MMU)
1162 		case 'u':
1163 			dump_segments();
1164 			break;
1165 #elif defined(CONFIG_44x)
1166 		case 'u':
1167 			dump_tlb_44x();
1168 			break;
1169 #elif defined(CONFIG_PPC_BOOK3E)
1170 		case 'u':
1171 			dump_tlb_book3e();
1172 			break;
1173 #endif
1174 		case 'U':
1175 			show_uptime();
1176 			break;
1177 		default:
1178 			printf("Unrecognized command: ");
1179 			do {
1180 				if (' ' < cmd && cmd <= '~')
1181 					putchar(cmd);
1182 				else
1183 					printf("\\x%x", cmd);
1184 				cmd = inchar();
1185 			} while (cmd != '\n');
1186 			printf(" (type ? for help)\n");
1187 			break;
1188 		}
1189 	}
1190 }
1191 
1192 #ifdef CONFIG_BOOKE
1193 static int do_step(struct pt_regs *regs)
1194 {
1195 	regs_set_return_msr(regs, regs->msr | MSR_DE);
1196 	mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM);
1197 	return 1;
1198 }
1199 #else
1200 /*
1201  * Step a single instruction.
1202  * Some instructions we emulate, others we execute with MSR_SE set.
1203  */
1204 static int do_step(struct pt_regs *regs)
1205 {
1206 	ppc_inst_t instr;
1207 	int stepped;
1208 
1209 	force_enable_xmon();
1210 	/* check we are in 64-bit kernel mode, translation enabled */
1211 	if ((regs->msr & (MSR_64BIT|MSR_PR|MSR_IR)) == (MSR_64BIT|MSR_IR)) {
1212 		if (mread_instr(regs->nip, &instr)) {
1213 			stepped = emulate_step(regs, instr);
1214 			if (stepped < 0) {
1215 				printf("Couldn't single-step %s instruction\n",
1216 				       (IS_RFID(instr)? "rfid": "mtmsrd"));
1217 				return 0;
1218 			}
1219 			if (stepped > 0) {
1220 				set_trap(regs, 0xd00);
1221 				printf("stepped to ");
1222 				xmon_print_symbol(regs->nip, " ", "\n");
1223 				ppc_inst_dump(regs->nip, 1, 0);
1224 				return 0;
1225 			}
1226 		}
1227 	}
1228 	regs_set_return_msr(regs, regs->msr | MSR_SE);
1229 	return 1;
1230 }
1231 #endif
1232 
1233 static void bootcmds(void)
1234 {
1235 	char tmp[64];
1236 	int cmd;
1237 
1238 	cmd = inchar();
1239 	if (cmd == 'r') {
1240 		getstring(tmp, 64);
1241 		ppc_md.restart(tmp);
1242 	} else if (cmd == 'h') {
1243 		ppc_md.halt();
1244 	} else if (cmd == 'p') {
1245 		do_kernel_power_off();
1246 	}
1247 }
1248 
1249 #ifdef CONFIG_SMP
1250 static int xmon_switch_cpu(unsigned long cpu)
1251 {
1252 	int timeout;
1253 
1254 	xmon_taken = 0;
1255 	mb();
1256 	xmon_owner = cpu;
1257 	timeout = 10000000;
1258 	while (!xmon_taken) {
1259 		if (--timeout == 0) {
1260 			if (test_and_set_bit(0, &xmon_taken))
1261 				break;
1262 			/* take control back */
1263 			mb();
1264 			xmon_owner = smp_processor_id();
1265 			printf("cpu 0x%lx didn't take control\n", cpu);
1266 			return 0;
1267 		}
1268 		barrier();
1269 	}
1270 	return 1;
1271 }
1272 
1273 static int xmon_batch_next_cpu(void)
1274 {
1275 	unsigned long cpu;
1276 
1277 	while (!cpumask_empty(&xmon_batch_cpus)) {
1278 		cpu = cpumask_next_wrap(smp_processor_id(), &xmon_batch_cpus,
1279 					xmon_batch_start_cpu, true);
1280 		if (cpu == nr_cpumask_bits)
1281 			break;
1282 		if (xmon_batch_start_cpu == -1)
1283 			xmon_batch_start_cpu = cpu;
1284 		if (xmon_switch_cpu(cpu))
1285 			return 0;
1286 		cpumask_clear_cpu(cpu, &xmon_batch_cpus);
1287 	}
1288 
1289 	xmon_batch = 0;
1290 	printf("%x:mon> \n", smp_processor_id());
1291 	return 1;
1292 }
1293 
1294 static int batch_cmds(struct pt_regs *excp)
1295 {
1296 	int cmd;
1297 
1298 	/* simulate command entry */
1299 	cmd = xmon_batch;
1300 	termch = '\n';
1301 
1302 	last_cmd = NULL;
1303 	xmon_regs = excp;
1304 
1305 	printf("%x:", smp_processor_id());
1306 	printf("mon> ");
1307 	printf("%c\n", (char)cmd);
1308 
1309 	switch (cmd) {
1310 	case 'r':
1311 		prregs(excp);	/* print regs */
1312 		break;
1313 	case 'S':
1314 		super_regs();
1315 		break;
1316 	case 't':
1317 		backtrace(excp);
1318 		break;
1319 	}
1320 
1321 	cpumask_clear_cpu(smp_processor_id(), &xmon_batch_cpus);
1322 
1323 	return xmon_batch_next_cpu();
1324 }
1325 
1326 static int cpu_cmd(void)
1327 {
1328 	unsigned long cpu, first_cpu, last_cpu;
1329 
1330 	cpu = skipbl();
1331 	if (cpu == '#') {
1332 		xmon_batch = skipbl();
1333 		if (xmon_batch) {
1334 			switch (xmon_batch) {
1335 			case 'r':
1336 			case 'S':
1337 			case 't':
1338 				cpumask_copy(&xmon_batch_cpus, &cpus_in_xmon);
1339 				if (cpumask_weight(&xmon_batch_cpus) <= 1) {
1340 					printf("There are no other cpus in xmon\n");
1341 					break;
1342 				}
1343 				xmon_batch_start_cpu = -1;
1344 				if (!xmon_batch_next_cpu())
1345 					return 1;
1346 				break;
1347 			default:
1348 				printf("c# only supports 'r', 'S' and 't' commands\n");
1349 			}
1350 			xmon_batch = 0;
1351 			return 0;
1352 		}
1353 	}
1354 	termch = cpu;
1355 
1356 	if (!scanhex(&cpu)) {
1357 		/* print cpus waiting or in xmon */
1358 		printf("cpus stopped:");
1359 		last_cpu = first_cpu = NR_CPUS;
1360 		for_each_possible_cpu(cpu) {
1361 			if (cpumask_test_cpu(cpu, &cpus_in_xmon)) {
1362 				if (cpu == last_cpu + 1) {
1363 					last_cpu = cpu;
1364 				} else {
1365 					if (last_cpu != first_cpu)
1366 						printf("-0x%lx", last_cpu);
1367 					last_cpu = first_cpu = cpu;
1368 					printf(" 0x%lx", cpu);
1369 				}
1370 			}
1371 		}
1372 		if (last_cpu != first_cpu)
1373 			printf("-0x%lx", last_cpu);
1374 		printf("\n");
1375 		return 0;
1376 	}
1377 	/* try to switch to cpu specified */
1378 	if (!cpumask_test_cpu(cpu, &cpus_in_xmon)) {
1379 		printf("cpu 0x%lx isn't in xmon\n", cpu);
1380 #ifdef CONFIG_PPC64
1381 		printf("backtrace of paca[0x%lx].saved_r1 (possibly stale):\n", cpu);
1382 		xmon_show_stack(paca_ptrs[cpu]->saved_r1, 0, 0);
1383 #endif
1384 		return 0;
1385 	}
1386 
1387 	return xmon_switch_cpu(cpu);
1388 }
1389 #else
1390 static int cpu_cmd(void)
1391 {
1392 	return 0;
1393 }
1394 #endif /* CONFIG_SMP */
1395 
1396 static unsigned short fcstab[256] = {
1397 	0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
1398 	0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
1399 	0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
1400 	0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
1401 	0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
1402 	0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
1403 	0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
1404 	0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
1405 	0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
1406 	0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
1407 	0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
1408 	0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
1409 	0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
1410 	0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
1411 	0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
1412 	0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
1413 	0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
1414 	0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
1415 	0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
1416 	0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
1417 	0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
1418 	0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
1419 	0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
1420 	0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
1421 	0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
1422 	0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
1423 	0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
1424 	0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
1425 	0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
1426 	0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
1427 	0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
1428 	0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
1429 };
1430 
1431 #define FCS(fcs, c)	(((fcs) >> 8) ^ fcstab[((fcs) ^ (c)) & 0xff])
1432 
1433 static void
1434 csum(void)
1435 {
1436 	unsigned int i;
1437 	unsigned short fcs;
1438 	unsigned char v;
1439 
1440 	if (!scanhex(&adrs))
1441 		return;
1442 	if (!scanhex(&ncsum))
1443 		return;
1444 	fcs = 0xffff;
1445 	for (i = 0; i < ncsum; ++i) {
1446 		if (mread(adrs+i, &v, 1) == 0) {
1447 			printf("csum stopped at "REG"\n", adrs+i);
1448 			break;
1449 		}
1450 		fcs = FCS(fcs, v);
1451 	}
1452 	printf("%x\n", fcs);
1453 }
1454 
1455 /*
1456  * Check if this is a suitable place to put a breakpoint.
1457  */
1458 static long check_bp_loc(unsigned long addr)
1459 {
1460 	ppc_inst_t instr;
1461 
1462 	addr &= ~3;
1463 	if (!is_kernel_addr(addr)) {
1464 		printf("Breakpoints may only be placed at kernel addresses\n");
1465 		return 0;
1466 	}
1467 	if (!mread_instr(addr, &instr)) {
1468 		printf("Can't read instruction at address %lx\n", addr);
1469 		return 0;
1470 	}
1471 	if (!can_single_step(ppc_inst_val(instr))) {
1472 		printf("Breakpoints may not be placed on instructions that can't be single stepped\n");
1473 		return 0;
1474 	}
1475 	return 1;
1476 }
1477 
1478 static int find_free_data_bpt(void)
1479 {
1480 	int i;
1481 
1482 	for (i = 0; i < nr_wp_slots(); i++) {
1483 		if (!dabr[i].enabled)
1484 			return i;
1485 	}
1486 	printf("Couldn't find free breakpoint register\n");
1487 	return -1;
1488 }
1489 
1490 static void print_data_bpts(void)
1491 {
1492 	int i;
1493 
1494 	for (i = 0; i < nr_wp_slots(); i++) {
1495 		if (!dabr[i].enabled)
1496 			continue;
1497 
1498 		printf("   data   "REG"  [", dabr[i].address);
1499 		if (dabr[i].enabled & 1)
1500 			printf("r");
1501 		if (dabr[i].enabled & 2)
1502 			printf("w");
1503 		printf("]\n");
1504 	}
1505 }
1506 
1507 static char *breakpoint_help_string =
1508     "Breakpoint command usage:\n"
1509     "b                show breakpoints\n"
1510     "b <addr> [cnt]   set breakpoint at given instr addr\n"
1511     "bc               clear all breakpoints\n"
1512     "bc <n/addr>      clear breakpoint number n or at addr\n"
1513     "bi <addr> [cnt]  set hardware instr breakpoint (POWER8 only)\n"
1514     "bd <addr> [cnt]  set hardware data breakpoint\n"
1515     "";
1516 
1517 static void
1518 bpt_cmds(void)
1519 {
1520 	int cmd;
1521 	unsigned long a;
1522 	int i;
1523 	struct bpt *bp;
1524 
1525 	cmd = inchar();
1526 
1527 	switch (cmd) {
1528 	static const char badaddr[] = "Only kernel addresses are permitted for breakpoints\n";
1529 	int mode;
1530 	case 'd':	/* bd - hardware data breakpoint */
1531 		if (xmon_is_ro) {
1532 			printf(xmon_ro_msg);
1533 			break;
1534 		}
1535 		if (!ppc_breakpoint_available()) {
1536 			printf("Hardware data breakpoint not supported on this cpu\n");
1537 			break;
1538 		}
1539 		i = find_free_data_bpt();
1540 		if (i < 0)
1541 			break;
1542 		mode = 7;
1543 		cmd = inchar();
1544 		if (cmd == 'r')
1545 			mode = 5;
1546 		else if (cmd == 'w')
1547 			mode = 6;
1548 		else
1549 			termch = cmd;
1550 		dabr[i].address = 0;
1551 		dabr[i].enabled = 0;
1552 		if (scanhex(&dabr[i].address)) {
1553 			if (!is_kernel_addr(dabr[i].address)) {
1554 				printf(badaddr);
1555 				break;
1556 			}
1557 			dabr[i].address &= ~HW_BRK_TYPE_DABR;
1558 			dabr[i].enabled = mode | BP_DABR;
1559 		}
1560 
1561 		force_enable_xmon();
1562 		break;
1563 
1564 	case 'i':	/* bi - hardware instr breakpoint */
1565 		if (xmon_is_ro) {
1566 			printf(xmon_ro_msg);
1567 			break;
1568 		}
1569 		if (!cpu_has_feature(CPU_FTR_ARCH_207S)) {
1570 			printf("Hardware instruction breakpoint "
1571 			       "not supported on this cpu\n");
1572 			break;
1573 		}
1574 		if (iabr) {
1575 			iabr->enabled &= ~BP_CIABR;
1576 			iabr = NULL;
1577 		}
1578 		if (!scanhex(&a))
1579 			break;
1580 		if (!check_bp_loc(a))
1581 			break;
1582 		bp = new_breakpoint(a);
1583 		if (bp != NULL) {
1584 			bp->enabled |= BP_CIABR;
1585 			iabr = bp;
1586 			force_enable_xmon();
1587 		}
1588 		break;
1589 
1590 	case 'c':
1591 		if (!scanhex(&a)) {
1592 			/* clear all breakpoints */
1593 			for (i = 0; i < NBPTS; ++i)
1594 				bpts[i].enabled = 0;
1595 			iabr = NULL;
1596 			for (i = 0; i < nr_wp_slots(); i++)
1597 				dabr[i].enabled = 0;
1598 
1599 			printf("All breakpoints cleared\n");
1600 			break;
1601 		}
1602 
1603 		if (a <= NBPTS && a >= 1) {
1604 			/* assume a breakpoint number */
1605 			bp = &bpts[a-1];	/* bp nums are 1 based */
1606 		} else {
1607 			/* assume a breakpoint address */
1608 			bp = at_breakpoint(a);
1609 			if (bp == NULL) {
1610 				printf("No breakpoint at %lx\n", a);
1611 				break;
1612 			}
1613 		}
1614 
1615 		printf("Cleared breakpoint %tx (", BP_NUM(bp));
1616 		xmon_print_symbol(bp->address, " ", ")\n");
1617 		bp->enabled = 0;
1618 		break;
1619 
1620 	default:
1621 		termch = cmd;
1622 		cmd = skipbl();
1623 		if (cmd == '?') {
1624 			printf(breakpoint_help_string);
1625 			break;
1626 		}
1627 		termch = cmd;
1628 
1629 		if (xmon_is_ro || !scanhex(&a)) {
1630 			/* print all breakpoints */
1631 			printf("   type            address\n");
1632 			print_data_bpts();
1633 			for (bp = bpts; bp < &bpts[NBPTS]; ++bp) {
1634 				if (!bp->enabled)
1635 					continue;
1636 				printf("%tx %s   ", BP_NUM(bp),
1637 				    (bp->enabled & BP_CIABR) ? "inst": "trap");
1638 				xmon_print_symbol(bp->address, "  ", "\n");
1639 			}
1640 			break;
1641 		}
1642 
1643 		if (!check_bp_loc(a))
1644 			break;
1645 		bp = new_breakpoint(a);
1646 		if (bp != NULL) {
1647 			bp->enabled |= BP_TRAP;
1648 			force_enable_xmon();
1649 		}
1650 		break;
1651 	}
1652 }
1653 
1654 /* Very cheap human name for vector lookup. */
1655 static
1656 const char *getvecname(unsigned long vec)
1657 {
1658 	char *ret;
1659 
1660 	switch (vec) {
1661 	case 0x100:	ret = "(System Reset)"; break;
1662 	case 0x200:	ret = "(Machine Check)"; break;
1663 	case 0x300:	ret = "(Data Access)"; break;
1664 	case 0x380:
1665 		if (radix_enabled())
1666 			ret = "(Data Access Out of Range)";
1667 		else
1668 			ret = "(Data SLB Access)";
1669 		break;
1670 	case 0x400:	ret = "(Instruction Access)"; break;
1671 	case 0x480:
1672 		if (radix_enabled())
1673 			ret = "(Instruction Access Out of Range)";
1674 		else
1675 			ret = "(Instruction SLB Access)";
1676 		break;
1677 	case 0x500:	ret = "(Hardware Interrupt)"; break;
1678 	case 0x600:	ret = "(Alignment)"; break;
1679 	case 0x700:	ret = "(Program Check)"; break;
1680 	case 0x800:	ret = "(FPU Unavailable)"; break;
1681 	case 0x900:	ret = "(Decrementer)"; break;
1682 	case 0x980:	ret = "(Hypervisor Decrementer)"; break;
1683 	case 0xa00:	ret = "(Doorbell)"; break;
1684 	case 0xc00:	ret = "(System Call)"; break;
1685 	case 0xd00:	ret = "(Single Step)"; break;
1686 	case 0xe40:	ret = "(Emulation Assist)"; break;
1687 	case 0xe60:	ret = "(HMI)"; break;
1688 	case 0xe80:	ret = "(Hypervisor Doorbell)"; break;
1689 	case 0xf00:	ret = "(Performance Monitor)"; break;
1690 	case 0xf20:	ret = "(Altivec Unavailable)"; break;
1691 	case 0x1300:	ret = "(Instruction Breakpoint)"; break;
1692 	case 0x1500:	ret = "(Denormalisation)"; break;
1693 	case 0x1700:	ret = "(Altivec Assist)"; break;
1694 	case 0x3000:	ret = "(System Call Vectored)"; break;
1695 	default: ret = "";
1696 	}
1697 	return ret;
1698 }
1699 
1700 static void get_function_bounds(unsigned long pc, unsigned long *startp,
1701 				unsigned long *endp)
1702 {
1703 	unsigned long size, offset;
1704 	const char *name;
1705 
1706 	*startp = *endp = 0;
1707 	if (pc == 0)
1708 		return;
1709 	if (setjmp(bus_error_jmp) == 0) {
1710 		catch_memory_errors = 1;
1711 		sync();
1712 		name = kallsyms_lookup(pc, &size, &offset, NULL, tmpstr);
1713 		if (name != NULL) {
1714 			*startp = pc - offset;
1715 			*endp = pc - offset + size;
1716 		}
1717 		sync();
1718 	}
1719 	catch_memory_errors = 0;
1720 }
1721 
1722 #define LRSAVE_OFFSET		(STACK_FRAME_LR_SAVE * sizeof(unsigned long))
1723 #define MARKER_OFFSET		(STACK_FRAME_MARKER * sizeof(unsigned long))
1724 
1725 static void xmon_show_stack(unsigned long sp, unsigned long lr,
1726 			    unsigned long pc)
1727 {
1728 	int max_to_print = 64;
1729 	unsigned long ip;
1730 	unsigned long newsp;
1731 	unsigned long marker;
1732 	struct pt_regs regs;
1733 
1734 	while (max_to_print--) {
1735 		if (!is_kernel_addr(sp)) {
1736 			if (sp != 0)
1737 				printf("SP (%lx) is in userspace\n", sp);
1738 			break;
1739 		}
1740 
1741 		if (!mread(sp + LRSAVE_OFFSET, &ip, sizeof(unsigned long))
1742 		    || !mread(sp, &newsp, sizeof(unsigned long))) {
1743 			printf("Couldn't read stack frame at %lx\n", sp);
1744 			break;
1745 		}
1746 
1747 		/*
1748 		 * For the first stack frame, try to work out if
1749 		 * LR and/or the saved LR value in the bottommost
1750 		 * stack frame are valid.
1751 		 */
1752 		if ((pc | lr) != 0) {
1753 			unsigned long fnstart, fnend;
1754 			unsigned long nextip;
1755 			int printip = 1;
1756 
1757 			get_function_bounds(pc, &fnstart, &fnend);
1758 			nextip = 0;
1759 			if (newsp > sp)
1760 				mread(newsp + LRSAVE_OFFSET, &nextip,
1761 				      sizeof(unsigned long));
1762 			if (lr == ip) {
1763 				if (!is_kernel_addr(lr)
1764 				    || (fnstart <= lr && lr < fnend))
1765 					printip = 0;
1766 			} else if (lr == nextip) {
1767 				printip = 0;
1768 			} else if (is_kernel_addr(lr)
1769 				   && !(fnstart <= lr && lr < fnend)) {
1770 				printf("[link register   ] ");
1771 				xmon_print_symbol(lr, " ", "\n");
1772 			}
1773 			if (printip) {
1774 				printf("["REG"] ", sp);
1775 				xmon_print_symbol(ip, " ", " (unreliable)\n");
1776 			}
1777 			pc = lr = 0;
1778 
1779 		} else {
1780 			printf("["REG"] ", sp);
1781 			xmon_print_symbol(ip, " ", "\n");
1782 		}
1783 
1784 		/* Look for "regshere" marker to see if this is
1785 		   an exception frame. */
1786 		if (mread(sp + MARKER_OFFSET, &marker, sizeof(unsigned long))
1787 		    && marker == STACK_FRAME_REGS_MARKER) {
1788 			if (mread(sp + STACK_FRAME_OVERHEAD, &regs, sizeof(regs))
1789 			    != sizeof(regs)) {
1790 				printf("Couldn't read registers at %lx\n",
1791 				       sp + STACK_FRAME_OVERHEAD);
1792 				break;
1793 			}
1794 			printf("--- Exception: %lx %s at ", regs.trap,
1795 			       getvecname(TRAP(&regs)));
1796 			pc = regs.nip;
1797 			lr = regs.link;
1798 			xmon_print_symbol(pc, " ", "\n");
1799 		}
1800 
1801 		if (newsp == 0)
1802 			break;
1803 
1804 		sp = newsp;
1805 	}
1806 }
1807 
1808 static void backtrace(struct pt_regs *excp)
1809 {
1810 	unsigned long sp;
1811 
1812 	if (scanhex(&sp))
1813 		xmon_show_stack(sp, 0, 0);
1814 	else
1815 		xmon_show_stack(excp->gpr[1], excp->link, excp->nip);
1816 	scannl();
1817 }
1818 
1819 static void print_bug_trap(struct pt_regs *regs)
1820 {
1821 #ifdef CONFIG_BUG
1822 	const struct bug_entry *bug;
1823 	unsigned long addr;
1824 
1825 	if (regs->msr & MSR_PR)
1826 		return;		/* not in kernel */
1827 	addr = regs->nip;	/* address of trap instruction */
1828 	if (!is_kernel_addr(addr))
1829 		return;
1830 	bug = find_bug(regs->nip);
1831 	if (bug == NULL)
1832 		return;
1833 	if (is_warning_bug(bug))
1834 		return;
1835 
1836 #ifdef CONFIG_DEBUG_BUGVERBOSE
1837 	printf("kernel BUG at %s:%u!\n",
1838 	       (char *)bug + bug->file_disp, bug->line);
1839 #else
1840 	printf("kernel BUG at %px!\n", (void *)bug + bug->bug_addr_disp);
1841 #endif
1842 #endif /* CONFIG_BUG */
1843 }
1844 
1845 static void excprint(struct pt_regs *fp)
1846 {
1847 	unsigned long trap;
1848 
1849 #ifdef CONFIG_SMP
1850 	printf("cpu 0x%x: ", smp_processor_id());
1851 #endif /* CONFIG_SMP */
1852 
1853 	trap = TRAP(fp);
1854 	printf("Vector: %lx %s at [%px]\n", fp->trap, getvecname(trap), fp);
1855 	printf("    pc: ");
1856 	xmon_print_symbol(fp->nip, ": ", "\n");
1857 
1858 	printf("    lr: ");
1859 	xmon_print_symbol(fp->link, ": ", "\n");
1860 
1861 	printf("    sp: %lx\n", fp->gpr[1]);
1862 	printf("   msr: %lx\n", fp->msr);
1863 
1864 	if (trap == INTERRUPT_DATA_STORAGE ||
1865 	    trap == INTERRUPT_DATA_SEGMENT ||
1866 	    trap == INTERRUPT_ALIGNMENT ||
1867 	    trap == INTERRUPT_MACHINE_CHECK) {
1868 		printf("   dar: %lx\n", fp->dar);
1869 		if (trap != INTERRUPT_DATA_SEGMENT)
1870 			printf(" dsisr: %lx\n", fp->dsisr);
1871 	}
1872 
1873 	printf("  current = 0x%px\n", current);
1874 #ifdef CONFIG_PPC64
1875 	printf("  paca    = 0x%px\t irqmask: 0x%02x\t irq_happened: 0x%02x\n",
1876 	       local_paca, local_paca->irq_soft_mask, local_paca->irq_happened);
1877 #endif
1878 	if (current) {
1879 		printf("    pid   = %d, comm = %s\n",
1880 		       current->pid, current->comm);
1881 	}
1882 
1883 	if (trap == INTERRUPT_PROGRAM)
1884 		print_bug_trap(fp);
1885 
1886 	printf(linux_banner);
1887 }
1888 
1889 static void prregs(struct pt_regs *fp)
1890 {
1891 	int n, trap;
1892 	unsigned long base;
1893 	struct pt_regs regs;
1894 
1895 	if (scanhex(&base)) {
1896 		if (setjmp(bus_error_jmp) == 0) {
1897 			catch_memory_errors = 1;
1898 			sync();
1899 			regs = *(struct pt_regs *)base;
1900 			sync();
1901 			__delay(200);
1902 		} else {
1903 			catch_memory_errors = 0;
1904 			printf("*** Error reading registers from "REG"\n",
1905 			       base);
1906 			return;
1907 		}
1908 		catch_memory_errors = 0;
1909 		fp = &regs;
1910 	}
1911 
1912 #ifdef CONFIG_PPC64
1913 #define R_PER_LINE 2
1914 #else
1915 #define R_PER_LINE 4
1916 #endif
1917 
1918 	for (n = 0; n < 32; ++n) {
1919 		printf("R%.2d = "REG"%s", n, fp->gpr[n],
1920 			(n % R_PER_LINE) == R_PER_LINE - 1 ? "\n" : "   ");
1921 	}
1922 
1923 	printf("pc  = ");
1924 	xmon_print_symbol(fp->nip, " ", "\n");
1925 	if (!trap_is_syscall(fp) && cpu_has_feature(CPU_FTR_CFAR)) {
1926 		printf("cfar= ");
1927 		xmon_print_symbol(fp->orig_gpr3, " ", "\n");
1928 	}
1929 	printf("lr  = ");
1930 	xmon_print_symbol(fp->link, " ", "\n");
1931 	printf("msr = "REG"   cr  = %.8lx\n", fp->msr, fp->ccr);
1932 	printf("ctr = "REG"   xer = "REG"   trap = %4lx\n",
1933 	       fp->ctr, fp->xer, fp->trap);
1934 	trap = TRAP(fp);
1935 	if (trap == INTERRUPT_DATA_STORAGE ||
1936 	    trap == INTERRUPT_DATA_SEGMENT ||
1937 	    trap == INTERRUPT_ALIGNMENT)
1938 		printf("dar = "REG"   dsisr = %.8lx\n", fp->dar, fp->dsisr);
1939 }
1940 
1941 static void cacheflush(void)
1942 {
1943 	int cmd;
1944 	unsigned long nflush;
1945 
1946 	cmd = inchar();
1947 	if (cmd != 'i')
1948 		termch = cmd;
1949 	scanhex((void *)&adrs);
1950 	if (termch != '\n')
1951 		termch = 0;
1952 	nflush = 1;
1953 	scanhex(&nflush);
1954 	nflush = (nflush + L1_CACHE_BYTES - 1) / L1_CACHE_BYTES;
1955 	if (setjmp(bus_error_jmp) == 0) {
1956 		catch_memory_errors = 1;
1957 		sync();
1958 
1959 		if (cmd != 'i' || IS_ENABLED(CONFIG_PPC_BOOK3S_64)) {
1960 			for (; nflush > 0; --nflush, adrs += L1_CACHE_BYTES)
1961 				cflush((void *) adrs);
1962 		} else {
1963 			for (; nflush > 0; --nflush, adrs += L1_CACHE_BYTES)
1964 				cinval((void *) adrs);
1965 		}
1966 		sync();
1967 		/* wait a little while to see if we get a machine check */
1968 		__delay(200);
1969 	}
1970 	catch_memory_errors = 0;
1971 }
1972 
1973 extern unsigned long xmon_mfspr(int spr, unsigned long default_value);
1974 extern void xmon_mtspr(int spr, unsigned long value);
1975 
1976 static int
1977 read_spr(int n, unsigned long *vp)
1978 {
1979 	unsigned long ret = -1UL;
1980 	int ok = 0;
1981 
1982 	if (setjmp(bus_error_jmp) == 0) {
1983 		catch_spr_faults = 1;
1984 		sync();
1985 
1986 		ret = xmon_mfspr(n, *vp);
1987 
1988 		sync();
1989 		*vp = ret;
1990 		ok = 1;
1991 	}
1992 	catch_spr_faults = 0;
1993 
1994 	return ok;
1995 }
1996 
1997 static void
1998 write_spr(int n, unsigned long val)
1999 {
2000 	if (xmon_is_ro) {
2001 		printf(xmon_ro_msg);
2002 		return;
2003 	}
2004 
2005 	if (setjmp(bus_error_jmp) == 0) {
2006 		catch_spr_faults = 1;
2007 		sync();
2008 
2009 		xmon_mtspr(n, val);
2010 
2011 		sync();
2012 	} else {
2013 		printf("SPR 0x%03x (%4d) Faulted during write\n", n, n);
2014 	}
2015 	catch_spr_faults = 0;
2016 }
2017 
2018 static void dump_206_sprs(void)
2019 {
2020 #ifdef CONFIG_PPC64
2021 	if (!cpu_has_feature(CPU_FTR_ARCH_206))
2022 		return;
2023 
2024 	/* Actually some of these pre-date 2.06, but whatever */
2025 
2026 	printf("srr0   = %.16lx  srr1  = %.16lx dsisr  = %.8lx\n",
2027 		mfspr(SPRN_SRR0), mfspr(SPRN_SRR1), mfspr(SPRN_DSISR));
2028 	printf("dscr   = %.16lx  ppr   = %.16lx pir    = %.8lx\n",
2029 		mfspr(SPRN_DSCR), mfspr(SPRN_PPR), mfspr(SPRN_PIR));
2030 	printf("amr    = %.16lx  uamor = %.16lx\n",
2031 		mfspr(SPRN_AMR), mfspr(SPRN_UAMOR));
2032 
2033 	if (!(mfmsr() & MSR_HV))
2034 		return;
2035 
2036 	printf("sdr1   = %.16lx  hdar  = %.16lx hdsisr = %.8lx\n",
2037 		mfspr(SPRN_SDR1), mfspr(SPRN_HDAR), mfspr(SPRN_HDSISR));
2038 	printf("hsrr0  = %.16lx hsrr1  = %.16lx hdec   = %.16lx\n",
2039 		mfspr(SPRN_HSRR0), mfspr(SPRN_HSRR1), mfspr(SPRN_HDEC));
2040 	printf("lpcr   = %.16lx  pcr   = %.16lx lpidr  = %.8lx\n",
2041 		mfspr(SPRN_LPCR), mfspr(SPRN_PCR), mfspr(SPRN_LPID));
2042 	printf("hsprg0 = %.16lx hsprg1 = %.16lx amor   = %.16lx\n",
2043 		mfspr(SPRN_HSPRG0), mfspr(SPRN_HSPRG1), mfspr(SPRN_AMOR));
2044 	printf("dabr   = %.16lx dabrx  = %.16lx\n",
2045 		mfspr(SPRN_DABR), mfspr(SPRN_DABRX));
2046 #endif
2047 }
2048 
2049 static void dump_207_sprs(void)
2050 {
2051 #ifdef CONFIG_PPC64
2052 	unsigned long msr;
2053 
2054 	if (!cpu_has_feature(CPU_FTR_ARCH_207S))
2055 		return;
2056 
2057 	printf("dpdes  = %.16lx  tir   = %.16lx cir    = %.8lx\n",
2058 		mfspr(SPRN_DPDES), mfspr(SPRN_TIR), mfspr(SPRN_CIR));
2059 
2060 	printf("fscr   = %.16lx  tar   = %.16lx pspb   = %.8lx\n",
2061 		mfspr(SPRN_FSCR), mfspr(SPRN_TAR), mfspr(SPRN_PSPB));
2062 
2063 	msr = mfmsr();
2064 	if (msr & MSR_TM) {
2065 		/* Only if TM has been enabled in the kernel */
2066 		printf("tfhar  = %.16lx  tfiar = %.16lx texasr = %.16lx\n",
2067 			mfspr(SPRN_TFHAR), mfspr(SPRN_TFIAR),
2068 			mfspr(SPRN_TEXASR));
2069 	}
2070 
2071 	printf("mmcr0  = %.16lx  mmcr1 = %.16lx mmcr2  = %.16lx\n",
2072 		mfspr(SPRN_MMCR0), mfspr(SPRN_MMCR1), mfspr(SPRN_MMCR2));
2073 	printf("pmc1   = %.8lx pmc2 = %.8lx  pmc3 = %.8lx  pmc4   = %.8lx\n",
2074 		mfspr(SPRN_PMC1), mfspr(SPRN_PMC2),
2075 		mfspr(SPRN_PMC3), mfspr(SPRN_PMC4));
2076 	printf("mmcra  = %.16lx   siar = %.16lx pmc5   = %.8lx\n",
2077 		mfspr(SPRN_MMCRA), mfspr(SPRN_SIAR), mfspr(SPRN_PMC5));
2078 	printf("sdar   = %.16lx   sier = %.16lx pmc6   = %.8lx\n",
2079 		mfspr(SPRN_SDAR), mfspr(SPRN_SIER), mfspr(SPRN_PMC6));
2080 	printf("ebbhr  = %.16lx  ebbrr = %.16lx bescr  = %.16lx\n",
2081 		mfspr(SPRN_EBBHR), mfspr(SPRN_EBBRR), mfspr(SPRN_BESCR));
2082 	printf("iamr   = %.16lx\n", mfspr(SPRN_IAMR));
2083 
2084 	if (!(msr & MSR_HV))
2085 		return;
2086 
2087 	printf("hfscr  = %.16lx  dhdes = %.16lx rpr    = %.16lx\n",
2088 		mfspr(SPRN_HFSCR), mfspr(SPRN_DHDES), mfspr(SPRN_RPR));
2089 	printf("dawr0  = %.16lx dawrx0 = %.16lx\n",
2090 	       mfspr(SPRN_DAWR0), mfspr(SPRN_DAWRX0));
2091 	if (nr_wp_slots() > 1) {
2092 		printf("dawr1  = %.16lx dawrx1 = %.16lx\n",
2093 		       mfspr(SPRN_DAWR1), mfspr(SPRN_DAWRX1));
2094 	}
2095 	printf("ciabr  = %.16lx\n", mfspr(SPRN_CIABR));
2096 #endif
2097 }
2098 
2099 static void dump_300_sprs(void)
2100 {
2101 #ifdef CONFIG_PPC64
2102 	bool hv = mfmsr() & MSR_HV;
2103 
2104 	if (!cpu_has_feature(CPU_FTR_ARCH_300))
2105 		return;
2106 
2107 	if (cpu_has_feature(CPU_FTR_P9_TIDR)) {
2108 		printf("pidr   = %.16lx  tidr  = %.16lx\n",
2109 			mfspr(SPRN_PID), mfspr(SPRN_TIDR));
2110 	} else {
2111 		printf("pidr   = %.16lx\n",
2112 			mfspr(SPRN_PID));
2113 	}
2114 
2115 	printf("psscr  = %.16lx\n",
2116 		hv ? mfspr(SPRN_PSSCR) : mfspr(SPRN_PSSCR_PR));
2117 
2118 	if (!hv)
2119 		return;
2120 
2121 	printf("ptcr   = %.16lx  asdr  = %.16lx\n",
2122 		mfspr(SPRN_PTCR), mfspr(SPRN_ASDR));
2123 #endif
2124 }
2125 
2126 static void dump_310_sprs(void)
2127 {
2128 #ifdef CONFIG_PPC64
2129 	if (!cpu_has_feature(CPU_FTR_ARCH_31))
2130 		return;
2131 
2132 	printf("mmcr3  = %.16lx, sier2  = %.16lx, sier3  = %.16lx\n",
2133 		mfspr(SPRN_MMCR3), mfspr(SPRN_SIER2), mfspr(SPRN_SIER3));
2134 
2135 #endif
2136 }
2137 
2138 static void dump_one_spr(int spr, bool show_unimplemented)
2139 {
2140 	unsigned long val;
2141 
2142 	val = 0xdeadbeef;
2143 	if (!read_spr(spr, &val)) {
2144 		printf("SPR 0x%03x (%4d) Faulted during read\n", spr, spr);
2145 		return;
2146 	}
2147 
2148 	if (val == 0xdeadbeef) {
2149 		/* Looks like read was a nop, confirm */
2150 		val = 0x0badcafe;
2151 		if (!read_spr(spr, &val)) {
2152 			printf("SPR 0x%03x (%4d) Faulted during read\n", spr, spr);
2153 			return;
2154 		}
2155 
2156 		if (val == 0x0badcafe) {
2157 			if (show_unimplemented)
2158 				printf("SPR 0x%03x (%4d) Unimplemented\n", spr, spr);
2159 			return;
2160 		}
2161 	}
2162 
2163 	printf("SPR 0x%03x (%4d) = 0x%lx\n", spr, spr, val);
2164 }
2165 
2166 static void super_regs(void)
2167 {
2168 	static unsigned long regno;
2169 	int cmd;
2170 	int spr;
2171 
2172 	cmd = skipbl();
2173 
2174 	switch (cmd) {
2175 	case '\n': {
2176 		unsigned long sp, toc;
2177 		asm("mr %0,1" : "=r" (sp) :);
2178 		asm("mr %0,2" : "=r" (toc) :);
2179 
2180 		printf("msr    = "REG"  sprg0 = "REG"\n",
2181 		       mfmsr(), mfspr(SPRN_SPRG0));
2182 		printf("pvr    = "REG"  sprg1 = "REG"\n",
2183 		       mfspr(SPRN_PVR), mfspr(SPRN_SPRG1));
2184 		printf("dec    = "REG"  sprg2 = "REG"\n",
2185 		       mfspr(SPRN_DEC), mfspr(SPRN_SPRG2));
2186 		printf("sp     = "REG"  sprg3 = "REG"\n", sp, mfspr(SPRN_SPRG3));
2187 		printf("toc    = "REG"  dar   = "REG"\n", toc, mfspr(SPRN_DAR));
2188 
2189 		dump_206_sprs();
2190 		dump_207_sprs();
2191 		dump_300_sprs();
2192 		dump_310_sprs();
2193 
2194 		return;
2195 	}
2196 	case 'w': {
2197 		unsigned long val;
2198 		scanhex(&regno);
2199 		val = 0;
2200 		read_spr(regno, &val);
2201 		scanhex(&val);
2202 		write_spr(regno, val);
2203 		dump_one_spr(regno, true);
2204 		break;
2205 	}
2206 	case 'r':
2207 		scanhex(&regno);
2208 		dump_one_spr(regno, true);
2209 		break;
2210 	case 'a':
2211 		/* dump ALL SPRs */
2212 		for (spr = 1; spr < 1024; ++spr)
2213 			dump_one_spr(spr, false);
2214 		break;
2215 	}
2216 
2217 	scannl();
2218 }
2219 
2220 /*
2221  * Stuff for reading and writing memory safely
2222  */
2223 static int
2224 mread(unsigned long adrs, void *buf, int size)
2225 {
2226 	volatile int n;
2227 	char *p, *q;
2228 
2229 	n = 0;
2230 	if (setjmp(bus_error_jmp) == 0) {
2231 		catch_memory_errors = 1;
2232 		sync();
2233 		p = (char *)adrs;
2234 		q = (char *)buf;
2235 		switch (size) {
2236 		case 2:
2237 			*(u16 *)q = *(u16 *)p;
2238 			break;
2239 		case 4:
2240 			*(u32 *)q = *(u32 *)p;
2241 			break;
2242 		case 8:
2243 			*(u64 *)q = *(u64 *)p;
2244 			break;
2245 		default:
2246 			for( ; n < size; ++n) {
2247 				*q++ = *p++;
2248 				sync();
2249 			}
2250 		}
2251 		sync();
2252 		/* wait a little while to see if we get a machine check */
2253 		__delay(200);
2254 		n = size;
2255 	}
2256 	catch_memory_errors = 0;
2257 	return n;
2258 }
2259 
2260 static int
2261 mwrite(unsigned long adrs, void *buf, int size)
2262 {
2263 	volatile int n;
2264 	char *p, *q;
2265 
2266 	n = 0;
2267 
2268 	if (xmon_is_ro) {
2269 		printf(xmon_ro_msg);
2270 		return n;
2271 	}
2272 
2273 	if (setjmp(bus_error_jmp) == 0) {
2274 		catch_memory_errors = 1;
2275 		sync();
2276 		p = (char *) adrs;
2277 		q = (char *) buf;
2278 		switch (size) {
2279 		case 2:
2280 			*(u16 *)p = *(u16 *)q;
2281 			break;
2282 		case 4:
2283 			*(u32 *)p = *(u32 *)q;
2284 			break;
2285 		case 8:
2286 			*(u64 *)p = *(u64 *)q;
2287 			break;
2288 		default:
2289 			for ( ; n < size; ++n) {
2290 				*p++ = *q++;
2291 				sync();
2292 			}
2293 		}
2294 		sync();
2295 		/* wait a little while to see if we get a machine check */
2296 		__delay(200);
2297 		n = size;
2298 	} else {
2299 		printf("*** Error writing address "REG"\n", adrs + n);
2300 	}
2301 	catch_memory_errors = 0;
2302 	return n;
2303 }
2304 
2305 static int
2306 mread_instr(unsigned long adrs, ppc_inst_t *instr)
2307 {
2308 	volatile int n;
2309 
2310 	n = 0;
2311 	if (setjmp(bus_error_jmp) == 0) {
2312 		catch_memory_errors = 1;
2313 		sync();
2314 		*instr = ppc_inst_read((u32 *)adrs);
2315 		sync();
2316 		/* wait a little while to see if we get a machine check */
2317 		__delay(200);
2318 		n = ppc_inst_len(*instr);
2319 	}
2320 	catch_memory_errors = 0;
2321 	return n;
2322 }
2323 
2324 static int fault_type;
2325 static int fault_except;
2326 static char *fault_chars[] = { "--", "**", "##" };
2327 
2328 static int handle_fault(struct pt_regs *regs)
2329 {
2330 	fault_except = TRAP(regs);
2331 	switch (TRAP(regs)) {
2332 	case 0x200:
2333 		fault_type = 0;
2334 		break;
2335 	case 0x300:
2336 	case 0x380:
2337 		fault_type = 1;
2338 		break;
2339 	default:
2340 		fault_type = 2;
2341 	}
2342 
2343 	longjmp(bus_error_jmp, 1);
2344 
2345 	return 0;
2346 }
2347 
2348 #define SWAP(a, b, t)	((t) = (a), (a) = (b), (b) = (t))
2349 
2350 static void
2351 byterev(unsigned char *val, int size)
2352 {
2353 	int t;
2354 
2355 	switch (size) {
2356 	case 2:
2357 		SWAP(val[0], val[1], t);
2358 		break;
2359 	case 4:
2360 		SWAP(val[0], val[3], t);
2361 		SWAP(val[1], val[2], t);
2362 		break;
2363 	case 8: /* is there really any use for this? */
2364 		SWAP(val[0], val[7], t);
2365 		SWAP(val[1], val[6], t);
2366 		SWAP(val[2], val[5], t);
2367 		SWAP(val[3], val[4], t);
2368 		break;
2369 	}
2370 }
2371 
2372 static int brev;
2373 static int mnoread;
2374 
2375 static char *memex_help_string =
2376     "Memory examine command usage:\n"
2377     "m [addr] [flags] examine/change memory\n"
2378     "  addr is optional.  will start where left off.\n"
2379     "  flags may include chars from this set:\n"
2380     "    b   modify by bytes (default)\n"
2381     "    w   modify by words (2 byte)\n"
2382     "    l   modify by longs (4 byte)\n"
2383     "    d   modify by doubleword (8 byte)\n"
2384     "    r   toggle reverse byte order mode\n"
2385     "    n   do not read memory (for i/o spaces)\n"
2386     "    .   ok to read (default)\n"
2387     "NOTE: flags are saved as defaults\n"
2388     "";
2389 
2390 static char *memex_subcmd_help_string =
2391     "Memory examine subcommands:\n"
2392     "  hexval   write this val to current location\n"
2393     "  'string' write chars from string to this location\n"
2394     "  '        increment address\n"
2395     "  ^        decrement address\n"
2396     "  /        increment addr by 0x10.  //=0x100, ///=0x1000, etc\n"
2397     "  \\        decrement addr by 0x10.  \\\\=0x100, \\\\\\=0x1000, etc\n"
2398     "  `        clear no-read flag\n"
2399     "  ;        stay at this addr\n"
2400     "  v        change to byte mode\n"
2401     "  w        change to word (2 byte) mode\n"
2402     "  l        change to long (4 byte) mode\n"
2403     "  u        change to doubleword (8 byte) mode\n"
2404     "  m addr   change current addr\n"
2405     "  n        toggle no-read flag\n"
2406     "  r        toggle byte reverse flag\n"
2407     "  < count  back up count bytes\n"
2408     "  > count  skip forward count bytes\n"
2409     "  x        exit this mode\n"
2410     "";
2411 
2412 static void
2413 memex(void)
2414 {
2415 	int cmd, inc, i, nslash;
2416 	unsigned long n;
2417 	unsigned char val[16];
2418 
2419 	scanhex((void *)&adrs);
2420 	cmd = skipbl();
2421 	if (cmd == '?') {
2422 		printf(memex_help_string);
2423 		return;
2424 	} else {
2425 		termch = cmd;
2426 	}
2427 	last_cmd = "m\n";
2428 	while ((cmd = skipbl()) != '\n') {
2429 		switch( cmd ){
2430 		case 'b':	size = 1;	break;
2431 		case 'w':	size = 2;	break;
2432 		case 'l':	size = 4;	break;
2433 		case 'd':	size = 8;	break;
2434 		case 'r': 	brev = !brev;	break;
2435 		case 'n':	mnoread = 1;	break;
2436 		case '.':	mnoread = 0;	break;
2437 		}
2438 	}
2439 	if( size <= 0 )
2440 		size = 1;
2441 	else if( size > 8 )
2442 		size = 8;
2443 	for(;;){
2444 		if (!mnoread)
2445 			n = mread(adrs, val, size);
2446 		printf(REG"%c", adrs, brev? 'r': ' ');
2447 		if (!mnoread) {
2448 			if (brev)
2449 				byterev(val, size);
2450 			putchar(' ');
2451 			for (i = 0; i < n; ++i)
2452 				printf("%.2x", val[i]);
2453 			for (; i < size; ++i)
2454 				printf("%s", fault_chars[fault_type]);
2455 		}
2456 		putchar(' ');
2457 		inc = size;
2458 		nslash = 0;
2459 		for(;;){
2460 			if( scanhex(&n) ){
2461 				for (i = 0; i < size; ++i)
2462 					val[i] = n >> (i * 8);
2463 				if (!brev)
2464 					byterev(val, size);
2465 				mwrite(adrs, val, size);
2466 				inc = size;
2467 			}
2468 			cmd = skipbl();
2469 			if (cmd == '\n')
2470 				break;
2471 			inc = 0;
2472 			switch (cmd) {
2473 			case '\'':
2474 				for(;;){
2475 					n = inchar();
2476 					if( n == '\\' )
2477 						n = bsesc();
2478 					else if( n == '\'' )
2479 						break;
2480 					for (i = 0; i < size; ++i)
2481 						val[i] = n >> (i * 8);
2482 					if (!brev)
2483 						byterev(val, size);
2484 					mwrite(adrs, val, size);
2485 					adrs += size;
2486 				}
2487 				adrs -= size;
2488 				inc = size;
2489 				break;
2490 			case ',':
2491 				adrs += size;
2492 				break;
2493 			case '.':
2494 				mnoread = 0;
2495 				break;
2496 			case ';':
2497 				break;
2498 			case 'x':
2499 			case EOF:
2500 				scannl();
2501 				return;
2502 			case 'b':
2503 			case 'v':
2504 				size = 1;
2505 				break;
2506 			case 'w':
2507 				size = 2;
2508 				break;
2509 			case 'l':
2510 				size = 4;
2511 				break;
2512 			case 'u':
2513 				size = 8;
2514 				break;
2515 			case '^':
2516 				adrs -= size;
2517 				break;
2518 			case '/':
2519 				if (nslash > 0)
2520 					adrs -= 1 << nslash;
2521 				else
2522 					nslash = 0;
2523 				nslash += 4;
2524 				adrs += 1 << nslash;
2525 				break;
2526 			case '\\':
2527 				if (nslash < 0)
2528 					adrs += 1 << -nslash;
2529 				else
2530 					nslash = 0;
2531 				nslash -= 4;
2532 				adrs -= 1 << -nslash;
2533 				break;
2534 			case 'm':
2535 				scanhex((void *)&adrs);
2536 				break;
2537 			case 'n':
2538 				mnoread = 1;
2539 				break;
2540 			case 'r':
2541 				brev = !brev;
2542 				break;
2543 			case '<':
2544 				n = size;
2545 				scanhex(&n);
2546 				adrs -= n;
2547 				break;
2548 			case '>':
2549 				n = size;
2550 				scanhex(&n);
2551 				adrs += n;
2552 				break;
2553 			case '?':
2554 				printf(memex_subcmd_help_string);
2555 				break;
2556 			}
2557 		}
2558 		adrs += inc;
2559 	}
2560 }
2561 
2562 static int
2563 bsesc(void)
2564 {
2565 	int c;
2566 
2567 	c = inchar();
2568 	switch( c ){
2569 	case 'n':	c = '\n';	break;
2570 	case 'r':	c = '\r';	break;
2571 	case 'b':	c = '\b';	break;
2572 	case 't':	c = '\t';	break;
2573 	}
2574 	return c;
2575 }
2576 
2577 static void xmon_rawdump (unsigned long adrs, long ndump)
2578 {
2579 	long n, m, r, nr;
2580 	unsigned char temp[16];
2581 
2582 	for (n = ndump; n > 0;) {
2583 		r = n < 16? n: 16;
2584 		nr = mread(adrs, temp, r);
2585 		adrs += nr;
2586 		for (m = 0; m < r; ++m) {
2587 			if (m < nr)
2588 				printf("%.2x", temp[m]);
2589 			else
2590 				printf("%s", fault_chars[fault_type]);
2591 		}
2592 		n -= r;
2593 		if (nr < r)
2594 			break;
2595 	}
2596 	printf("\n");
2597 }
2598 
2599 static void dump_tracing(void)
2600 {
2601 	int c;
2602 
2603 	c = inchar();
2604 	if (c == 'c')
2605 		ftrace_dump(DUMP_ORIG);
2606 	else
2607 		ftrace_dump(DUMP_ALL);
2608 }
2609 
2610 #ifdef CONFIG_PPC64
2611 static void dump_one_paca(int cpu)
2612 {
2613 	struct paca_struct *p;
2614 #ifdef CONFIG_PPC_64S_HASH_MMU
2615 	int i = 0;
2616 #endif
2617 
2618 	if (setjmp(bus_error_jmp) != 0) {
2619 		printf("*** Error dumping paca for cpu 0x%x!\n", cpu);
2620 		return;
2621 	}
2622 
2623 	catch_memory_errors = 1;
2624 	sync();
2625 
2626 	p = paca_ptrs[cpu];
2627 
2628 	printf("paca for cpu 0x%x @ %px:\n", cpu, p);
2629 
2630 	printf(" %-*s = %s\n", 25, "possible", cpu_possible(cpu) ? "yes" : "no");
2631 	printf(" %-*s = %s\n", 25, "present", cpu_present(cpu) ? "yes" : "no");
2632 	printf(" %-*s = %s\n", 25, "online", cpu_online(cpu) ? "yes" : "no");
2633 
2634 #define DUMP(paca, name, format)				\
2635 	printf(" %-*s = "format"\t(0x%lx)\n", 25, #name, 18, paca->name, \
2636 		offsetof(struct paca_struct, name));
2637 
2638 	DUMP(p, lock_token, "%#-*x");
2639 	DUMP(p, paca_index, "%#-*x");
2640 	DUMP(p, kernel_toc, "%#-*llx");
2641 	DUMP(p, kernelbase, "%#-*llx");
2642 	DUMP(p, kernel_msr, "%#-*llx");
2643 	DUMP(p, emergency_sp, "%-*px");
2644 #ifdef CONFIG_PPC_BOOK3S_64
2645 	DUMP(p, nmi_emergency_sp, "%-*px");
2646 	DUMP(p, mc_emergency_sp, "%-*px");
2647 	DUMP(p, in_nmi, "%#-*x");
2648 	DUMP(p, in_mce, "%#-*x");
2649 	DUMP(p, hmi_event_available, "%#-*x");
2650 #endif
2651 	DUMP(p, data_offset, "%#-*llx");
2652 	DUMP(p, hw_cpu_id, "%#-*x");
2653 	DUMP(p, cpu_start, "%#-*x");
2654 	DUMP(p, kexec_state, "%#-*x");
2655 #ifdef CONFIG_PPC_BOOK3S_64
2656 #ifdef CONFIG_PPC_64S_HASH_MMU
2657 	if (!early_radix_enabled()) {
2658 		for (i = 0; i < SLB_NUM_BOLTED; i++) {
2659 			u64 esid, vsid;
2660 
2661 			if (!p->slb_shadow_ptr)
2662 				continue;
2663 
2664 			esid = be64_to_cpu(p->slb_shadow_ptr->save_area[i].esid);
2665 			vsid = be64_to_cpu(p->slb_shadow_ptr->save_area[i].vsid);
2666 
2667 			if (esid || vsid) {
2668 				printf(" %-*s[%d] = 0x%016llx 0x%016llx\n",
2669 				       22, "slb_shadow", i, esid, vsid);
2670 			}
2671 		}
2672 		DUMP(p, vmalloc_sllp, "%#-*x");
2673 		DUMP(p, stab_rr, "%#-*x");
2674 		DUMP(p, slb_used_bitmap, "%#-*x");
2675 		DUMP(p, slb_kern_bitmap, "%#-*x");
2676 
2677 		if (!early_cpu_has_feature(CPU_FTR_ARCH_300)) {
2678 			DUMP(p, slb_cache_ptr, "%#-*x");
2679 			for (i = 0; i < SLB_CACHE_ENTRIES; i++)
2680 				printf(" %-*s[%d] = 0x%016x\n",
2681 				       22, "slb_cache", i, p->slb_cache[i]);
2682 		}
2683 	}
2684 #endif
2685 
2686 	DUMP(p, rfi_flush_fallback_area, "%-*px");
2687 #endif
2688 	DUMP(p, dscr_default, "%#-*llx");
2689 #ifdef CONFIG_PPC_BOOK3E
2690 	DUMP(p, pgd, "%-*px");
2691 	DUMP(p, kernel_pgd, "%-*px");
2692 	DUMP(p, tcd_ptr, "%-*px");
2693 	DUMP(p, mc_kstack, "%-*px");
2694 	DUMP(p, crit_kstack, "%-*px");
2695 	DUMP(p, dbg_kstack, "%-*px");
2696 #endif
2697 	DUMP(p, __current, "%-*px");
2698 	DUMP(p, kstack, "%#-*llx");
2699 	printf(" %-*s = 0x%016llx\n", 25, "kstack_base", p->kstack & ~(THREAD_SIZE - 1));
2700 #ifdef CONFIG_STACKPROTECTOR
2701 	DUMP(p, canary, "%#-*lx");
2702 #endif
2703 	DUMP(p, saved_r1, "%#-*llx");
2704 #ifdef CONFIG_PPC_BOOK3E
2705 	DUMP(p, trap_save, "%#-*x");
2706 #endif
2707 	DUMP(p, irq_soft_mask, "%#-*x");
2708 	DUMP(p, irq_happened, "%#-*x");
2709 #ifdef CONFIG_MMIOWB
2710 	DUMP(p, mmiowb_state.nesting_count, "%#-*x");
2711 	DUMP(p, mmiowb_state.mmiowb_pending, "%#-*x");
2712 #endif
2713 	DUMP(p, irq_work_pending, "%#-*x");
2714 	DUMP(p, sprg_vdso, "%#-*llx");
2715 
2716 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2717 	DUMP(p, tm_scratch, "%#-*llx");
2718 #endif
2719 
2720 #ifdef CONFIG_PPC_POWERNV
2721 	DUMP(p, idle_state, "%#-*lx");
2722 	if (!early_cpu_has_feature(CPU_FTR_ARCH_300)) {
2723 		DUMP(p, thread_idle_state, "%#-*x");
2724 		DUMP(p, subcore_sibling_mask, "%#-*x");
2725 	} else {
2726 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
2727 		DUMP(p, requested_psscr, "%#-*llx");
2728 		DUMP(p, dont_stop.counter, "%#-*x");
2729 #endif
2730 	}
2731 #endif
2732 
2733 	DUMP(p, accounting.utime, "%#-*lx");
2734 	DUMP(p, accounting.stime, "%#-*lx");
2735 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
2736 	DUMP(p, accounting.utime_scaled, "%#-*lx");
2737 #endif
2738 	DUMP(p, accounting.starttime, "%#-*lx");
2739 	DUMP(p, accounting.starttime_user, "%#-*lx");
2740 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
2741 	DUMP(p, accounting.startspurr, "%#-*lx");
2742 	DUMP(p, accounting.utime_sspurr, "%#-*lx");
2743 #endif
2744 	DUMP(p, accounting.steal_time, "%#-*lx");
2745 #undef DUMP
2746 
2747 	catch_memory_errors = 0;
2748 	sync();
2749 }
2750 
2751 static void dump_all_pacas(void)
2752 {
2753 	int cpu;
2754 
2755 	if (num_possible_cpus() == 0) {
2756 		printf("No possible cpus, use 'dp #' to dump individual cpus\n");
2757 		return;
2758 	}
2759 
2760 	for_each_possible_cpu(cpu)
2761 		dump_one_paca(cpu);
2762 }
2763 
2764 static void dump_pacas(void)
2765 {
2766 	unsigned long num;
2767 	int c;
2768 
2769 	c = inchar();
2770 	if (c == 'a') {
2771 		dump_all_pacas();
2772 		return;
2773 	}
2774 
2775 	termch = c;	/* Put c back, it wasn't 'a' */
2776 
2777 	if (scanhex(&num))
2778 		dump_one_paca(num);
2779 	else
2780 		dump_one_paca(xmon_owner);
2781 }
2782 #endif
2783 
2784 #ifdef CONFIG_PPC_POWERNV
2785 static void dump_one_xive(int cpu)
2786 {
2787 	unsigned int hwid = get_hard_smp_processor_id(cpu);
2788 	bool hv = cpu_has_feature(CPU_FTR_HVMODE);
2789 
2790 	if (hv) {
2791 		opal_xive_dump(XIVE_DUMP_TM_HYP, hwid);
2792 		opal_xive_dump(XIVE_DUMP_TM_POOL, hwid);
2793 		opal_xive_dump(XIVE_DUMP_TM_OS, hwid);
2794 		opal_xive_dump(XIVE_DUMP_TM_USER, hwid);
2795 		opal_xive_dump(XIVE_DUMP_VP, hwid);
2796 		opal_xive_dump(XIVE_DUMP_EMU_STATE, hwid);
2797 	}
2798 
2799 	if (setjmp(bus_error_jmp) != 0) {
2800 		catch_memory_errors = 0;
2801 		printf("*** Error dumping xive on cpu %d\n", cpu);
2802 		return;
2803 	}
2804 
2805 	catch_memory_errors = 1;
2806 	sync();
2807 	xmon_xive_do_dump(cpu);
2808 	sync();
2809 	__delay(200);
2810 	catch_memory_errors = 0;
2811 }
2812 
2813 static void dump_all_xives(void)
2814 {
2815 	int cpu;
2816 
2817 	if (num_online_cpus() == 0) {
2818 		printf("No possible cpus, use 'dx #' to dump individual cpus\n");
2819 		return;
2820 	}
2821 
2822 	for_each_online_cpu(cpu)
2823 		dump_one_xive(cpu);
2824 }
2825 
2826 static void dump_xives(void)
2827 {
2828 	unsigned long num;
2829 	int c;
2830 
2831 	if (!xive_enabled()) {
2832 		printf("Xive disabled on this system\n");
2833 		return;
2834 	}
2835 
2836 	c = inchar();
2837 	if (c == 'a') {
2838 		dump_all_xives();
2839 		return;
2840 	} else if (c == 'i') {
2841 		if (scanhex(&num))
2842 			xmon_xive_get_irq_config(num, NULL);
2843 		else
2844 			xmon_xive_get_irq_all();
2845 		return;
2846 	}
2847 
2848 	termch = c;	/* Put c back, it wasn't 'a' */
2849 
2850 	if (scanhex(&num))
2851 		dump_one_xive(num);
2852 	else
2853 		dump_one_xive(xmon_owner);
2854 }
2855 #endif /* CONFIG_PPC_POWERNV */
2856 
2857 static void dump_by_size(unsigned long addr, long count, int size)
2858 {
2859 	unsigned char temp[16];
2860 	int i, j;
2861 	u64 val;
2862 
2863 	count = ALIGN(count, 16);
2864 
2865 	for (i = 0; i < count; i += 16, addr += 16) {
2866 		printf(REG, addr);
2867 
2868 		if (mread(addr, temp, 16) != 16) {
2869 			printf("\nFaulted reading %d bytes from 0x"REG"\n", 16, addr);
2870 			return;
2871 		}
2872 
2873 		for (j = 0; j < 16; j += size) {
2874 			putchar(' ');
2875 			switch (size) {
2876 			case 1: val = temp[j]; break;
2877 			case 2: val = *(u16 *)&temp[j]; break;
2878 			case 4: val = *(u32 *)&temp[j]; break;
2879 			case 8: val = *(u64 *)&temp[j]; break;
2880 			default: val = 0;
2881 			}
2882 
2883 			printf("%0*llx", size * 2, val);
2884 		}
2885 		printf("  |");
2886 		for (j = 0; j < 16; ++j) {
2887 			val = temp[j];
2888 			putchar(' ' <= val && val <= '~' ? val : '.');
2889 		}
2890 		printf("|\n");
2891 	}
2892 }
2893 
2894 static void
2895 dump(void)
2896 {
2897 	static char last[] = { "d?\n" };
2898 	int c;
2899 
2900 	c = inchar();
2901 
2902 #ifdef CONFIG_PPC64
2903 	if (c == 'p') {
2904 		xmon_start_pagination();
2905 		dump_pacas();
2906 		xmon_end_pagination();
2907 		return;
2908 	}
2909 #endif
2910 #ifdef CONFIG_PPC_POWERNV
2911 	if (c == 'x') {
2912 		xmon_start_pagination();
2913 		dump_xives();
2914 		xmon_end_pagination();
2915 		return;
2916 	}
2917 #endif
2918 
2919 	if (c == 't') {
2920 		dump_tracing();
2921 		return;
2922 	}
2923 
2924 	if (c == '\n')
2925 		termch = c;
2926 
2927 	scanhex((void *)&adrs);
2928 	if (termch != '\n')
2929 		termch = 0;
2930 	if (c == 'i') {
2931 		scanhex(&nidump);
2932 		if (nidump == 0)
2933 			nidump = 16;
2934 		else if (nidump > MAX_IDUMP)
2935 			nidump = MAX_IDUMP;
2936 		adrs += ppc_inst_dump(adrs, nidump, 1);
2937 		last_cmd = "di\n";
2938 	} else if (c == 'l') {
2939 		dump_log_buf();
2940 	} else if (c == 'o') {
2941 		dump_opal_msglog();
2942 	} else if (c == 'v') {
2943 		/* dump virtual to physical translation */
2944 		show_pte(adrs);
2945 	} else if (c == 'r') {
2946 		scanhex(&ndump);
2947 		if (ndump == 0)
2948 			ndump = 64;
2949 		xmon_rawdump(adrs, ndump);
2950 		adrs += ndump;
2951 		last_cmd = "dr\n";
2952 	} else {
2953 		scanhex(&ndump);
2954 		if (ndump == 0)
2955 			ndump = 64;
2956 		else if (ndump > MAX_DUMP)
2957 			ndump = MAX_DUMP;
2958 
2959 		switch (c) {
2960 		case '8':
2961 		case '4':
2962 		case '2':
2963 		case '1':
2964 			ndump = ALIGN(ndump, 16);
2965 			dump_by_size(adrs, ndump, c - '0');
2966 			last[1] = c;
2967 			last_cmd = last;
2968 			break;
2969 		default:
2970 			prdump(adrs, ndump);
2971 			last_cmd = "d\n";
2972 		}
2973 
2974 		adrs += ndump;
2975 	}
2976 }
2977 
2978 static void
2979 prdump(unsigned long adrs, long ndump)
2980 {
2981 	long n, m, c, r, nr;
2982 	unsigned char temp[16];
2983 
2984 	for (n = ndump; n > 0;) {
2985 		printf(REG, adrs);
2986 		putchar(' ');
2987 		r = n < 16? n: 16;
2988 		nr = mread(adrs, temp, r);
2989 		adrs += nr;
2990 		for (m = 0; m < r; ++m) {
2991 			if ((m & (sizeof(long) - 1)) == 0 && m > 0)
2992 				putchar(' ');
2993 			if (m < nr)
2994 				printf("%.2x", temp[m]);
2995 			else
2996 				printf("%s", fault_chars[fault_type]);
2997 		}
2998 		for (; m < 16; ++m) {
2999 			if ((m & (sizeof(long) - 1)) == 0)
3000 				putchar(' ');
3001 			printf("  ");
3002 		}
3003 		printf("  |");
3004 		for (m = 0; m < r; ++m) {
3005 			if (m < nr) {
3006 				c = temp[m];
3007 				putchar(' ' <= c && c <= '~'? c: '.');
3008 			} else
3009 				putchar(' ');
3010 		}
3011 		n -= r;
3012 		for (; m < 16; ++m)
3013 			putchar(' ');
3014 		printf("|\n");
3015 		if (nr < r)
3016 			break;
3017 	}
3018 }
3019 
3020 typedef int (*instruction_dump_func)(unsigned long inst, unsigned long addr);
3021 
3022 static int
3023 generic_inst_dump(unsigned long adr, long count, int praddr,
3024 			instruction_dump_func dump_func)
3025 {
3026 	int nr, dotted;
3027 	unsigned long first_adr;
3028 	ppc_inst_t inst, last_inst = ppc_inst(0);
3029 
3030 	dotted = 0;
3031 	for (first_adr = adr; count > 0; --count, adr += ppc_inst_len(inst)) {
3032 		nr = mread_instr(adr, &inst);
3033 		if (nr == 0) {
3034 			if (praddr) {
3035 				const char *x = fault_chars[fault_type];
3036 				printf(REG"  %s%s%s%s\n", adr, x, x, x, x);
3037 			}
3038 			break;
3039 		}
3040 		if (adr > first_adr && ppc_inst_equal(inst, last_inst)) {
3041 			if (!dotted) {
3042 				printf(" ...\n");
3043 				dotted = 1;
3044 			}
3045 			continue;
3046 		}
3047 		dotted = 0;
3048 		last_inst = inst;
3049 		if (praddr)
3050 			printf(REG"  %08lx", adr, ppc_inst_as_ulong(inst));
3051 		printf("\t");
3052 		if (!ppc_inst_prefixed(inst))
3053 			dump_func(ppc_inst_val(inst), adr);
3054 		else
3055 			dump_func(ppc_inst_as_ulong(inst), adr);
3056 		printf("\n");
3057 	}
3058 	return adr - first_adr;
3059 }
3060 
3061 static int
3062 ppc_inst_dump(unsigned long adr, long count, int praddr)
3063 {
3064 	return generic_inst_dump(adr, count, praddr, print_insn_powerpc);
3065 }
3066 
3067 void
3068 print_address(unsigned long addr)
3069 {
3070 	xmon_print_symbol(addr, "\t# ", "");
3071 }
3072 
3073 static void
3074 dump_log_buf(void)
3075 {
3076 	struct kmsg_dump_iter iter;
3077 	static unsigned char buf[1024];
3078 	size_t len;
3079 
3080 	if (setjmp(bus_error_jmp) != 0) {
3081 		printf("Error dumping printk buffer!\n");
3082 		return;
3083 	}
3084 
3085 	catch_memory_errors = 1;
3086 	sync();
3087 
3088 	kmsg_dump_rewind(&iter);
3089 	xmon_start_pagination();
3090 	while (kmsg_dump_get_line(&iter, false, buf, sizeof(buf), &len)) {
3091 		buf[len] = '\0';
3092 		printf("%s", buf);
3093 	}
3094 	xmon_end_pagination();
3095 
3096 	sync();
3097 	/* wait a little while to see if we get a machine check */
3098 	__delay(200);
3099 	catch_memory_errors = 0;
3100 }
3101 
3102 #ifdef CONFIG_PPC_POWERNV
3103 static void dump_opal_msglog(void)
3104 {
3105 	unsigned char buf[128];
3106 	ssize_t res;
3107 	volatile loff_t pos = 0;
3108 
3109 	if (!firmware_has_feature(FW_FEATURE_OPAL)) {
3110 		printf("Machine is not running OPAL firmware.\n");
3111 		return;
3112 	}
3113 
3114 	if (setjmp(bus_error_jmp) != 0) {
3115 		printf("Error dumping OPAL msglog!\n");
3116 		return;
3117 	}
3118 
3119 	catch_memory_errors = 1;
3120 	sync();
3121 
3122 	xmon_start_pagination();
3123 	while ((res = opal_msglog_copy(buf, pos, sizeof(buf) - 1))) {
3124 		if (res < 0) {
3125 			printf("Error dumping OPAL msglog! Error: %zd\n", res);
3126 			break;
3127 		}
3128 		buf[res] = '\0';
3129 		printf("%s", buf);
3130 		pos += res;
3131 	}
3132 	xmon_end_pagination();
3133 
3134 	sync();
3135 	/* wait a little while to see if we get a machine check */
3136 	__delay(200);
3137 	catch_memory_errors = 0;
3138 }
3139 #endif
3140 
3141 /*
3142  * Memory operations - move, set, print differences
3143  */
3144 static unsigned long mdest;		/* destination address */
3145 static unsigned long msrc;		/* source address */
3146 static unsigned long mval;		/* byte value to set memory to */
3147 static unsigned long mcount;		/* # bytes to affect */
3148 static unsigned long mdiffs;		/* max # differences to print */
3149 
3150 static void
3151 memops(int cmd)
3152 {
3153 	scanhex((void *)&mdest);
3154 	if( termch != '\n' )
3155 		termch = 0;
3156 	scanhex((void *)(cmd == 's'? &mval: &msrc));
3157 	if( termch != '\n' )
3158 		termch = 0;
3159 	scanhex((void *)&mcount);
3160 	switch( cmd ){
3161 	case 'm':
3162 		if (xmon_is_ro) {
3163 			printf(xmon_ro_msg);
3164 			break;
3165 		}
3166 		memmove((void *)mdest, (void *)msrc, mcount);
3167 		break;
3168 	case 's':
3169 		if (xmon_is_ro) {
3170 			printf(xmon_ro_msg);
3171 			break;
3172 		}
3173 		memset((void *)mdest, mval, mcount);
3174 		break;
3175 	case 'd':
3176 		if( termch != '\n' )
3177 			termch = 0;
3178 		scanhex((void *)&mdiffs);
3179 		memdiffs((unsigned char *)mdest, (unsigned char *)msrc, mcount, mdiffs);
3180 		break;
3181 	}
3182 }
3183 
3184 static void
3185 memdiffs(unsigned char *p1, unsigned char *p2, unsigned nb, unsigned maxpr)
3186 {
3187 	unsigned n, prt;
3188 
3189 	prt = 0;
3190 	for( n = nb; n > 0; --n )
3191 		if( *p1++ != *p2++ )
3192 			if( ++prt <= maxpr )
3193 				printf("%px %.2x # %px %.2x\n", p1 - 1,
3194 					p1[-1], p2 - 1, p2[-1]);
3195 	if( prt > maxpr )
3196 		printf("Total of %d differences\n", prt);
3197 }
3198 
3199 static unsigned mend;
3200 static unsigned mask;
3201 
3202 static void
3203 memlocate(void)
3204 {
3205 	unsigned a, n;
3206 	unsigned char val[4];
3207 
3208 	last_cmd = "ml";
3209 	scanhex((void *)&mdest);
3210 	if (termch != '\n') {
3211 		termch = 0;
3212 		scanhex((void *)&mend);
3213 		if (termch != '\n') {
3214 			termch = 0;
3215 			scanhex((void *)&mval);
3216 			mask = ~0;
3217 			if (termch != '\n') termch = 0;
3218 			scanhex((void *)&mask);
3219 		}
3220 	}
3221 	n = 0;
3222 	for (a = mdest; a < mend; a += 4) {
3223 		if (mread(a, val, 4) == 4
3224 			&& ((GETWORD(val) ^ mval) & mask) == 0) {
3225 			printf("%.16x:  %.16x\n", a, GETWORD(val));
3226 			if (++n >= 10)
3227 				break;
3228 		}
3229 	}
3230 }
3231 
3232 static unsigned long mskip = 0x1000;
3233 static unsigned long mlim = 0xffffffff;
3234 
3235 static void
3236 memzcan(void)
3237 {
3238 	unsigned char v;
3239 	unsigned a;
3240 	int ok, ook;
3241 
3242 	scanhex(&mdest);
3243 	if (termch != '\n') termch = 0;
3244 	scanhex(&mskip);
3245 	if (termch != '\n') termch = 0;
3246 	scanhex(&mlim);
3247 	ook = 0;
3248 	for (a = mdest; a < mlim; a += mskip) {
3249 		ok = mread(a, &v, 1);
3250 		if (ok && !ook) {
3251 			printf("%.8x .. ", a);
3252 		} else if (!ok && ook)
3253 			printf("%.8lx\n", a - mskip);
3254 		ook = ok;
3255 		if (a + mskip < a)
3256 			break;
3257 	}
3258 	if (ook)
3259 		printf("%.8lx\n", a - mskip);
3260 }
3261 
3262 static void show_task(struct task_struct *volatile tsk)
3263 {
3264 	unsigned int p_state = READ_ONCE(tsk->__state);
3265 	char state;
3266 
3267 	/*
3268 	 * Cloned from kdb_task_state_char(), which is not entirely
3269 	 * appropriate for calling from xmon. This could be moved
3270 	 * to a common, generic, routine used by both.
3271 	 */
3272 	state = (p_state == TASK_RUNNING) ? 'R' :
3273 		(p_state & TASK_UNINTERRUPTIBLE) ? 'D' :
3274 		(p_state & TASK_STOPPED) ? 'T' :
3275 		(p_state & TASK_TRACED) ? 'C' :
3276 		(tsk->exit_state & EXIT_ZOMBIE) ? 'Z' :
3277 		(tsk->exit_state & EXIT_DEAD) ? 'E' :
3278 		(p_state & TASK_INTERRUPTIBLE) ? 'S' : '?';
3279 
3280 	printf("%16px %16lx %16px %6d %6d %c %2d %s\n", tsk,
3281 		tsk->thread.ksp, tsk->thread.regs,
3282 		tsk->pid, rcu_dereference(tsk->parent)->pid,
3283 		state, task_cpu(tsk),
3284 		tsk->comm);
3285 }
3286 
3287 #ifdef CONFIG_PPC_BOOK3S_64
3288 static void format_pte(void *ptep, unsigned long pte)
3289 {
3290 	pte_t entry = __pte(pte);
3291 
3292 	printf("ptep @ 0x%016lx = 0x%016lx\n", (unsigned long)ptep, pte);
3293 	printf("Maps physical address = 0x%016lx\n", pte & PTE_RPN_MASK);
3294 
3295 	printf("Flags = %s%s%s%s%s\n",
3296 	       pte_young(entry) ? "Accessed " : "",
3297 	       pte_dirty(entry) ? "Dirty " : "",
3298 	       pte_read(entry)  ? "Read " : "",
3299 	       pte_write(entry) ? "Write " : "",
3300 	       pte_exec(entry)  ? "Exec " : "");
3301 }
3302 
3303 static void show_pte(unsigned long addr)
3304 {
3305 	unsigned long tskv = 0;
3306 	struct task_struct *volatile tsk = NULL;
3307 	struct mm_struct *mm;
3308 	pgd_t *pgdp;
3309 	p4d_t *p4dp;
3310 	pud_t *pudp;
3311 	pmd_t *pmdp;
3312 	pte_t *ptep;
3313 
3314 	if (!scanhex(&tskv))
3315 		mm = &init_mm;
3316 	else
3317 		tsk = (struct task_struct *)tskv;
3318 
3319 	if (tsk == NULL)
3320 		mm = &init_mm;
3321 	else
3322 		mm = tsk->active_mm;
3323 
3324 	if (setjmp(bus_error_jmp) != 0) {
3325 		catch_memory_errors = 0;
3326 		printf("*** Error dumping pte for task %px\n", tsk);
3327 		return;
3328 	}
3329 
3330 	catch_memory_errors = 1;
3331 	sync();
3332 
3333 	if (mm == &init_mm)
3334 		pgdp = pgd_offset_k(addr);
3335 	else
3336 		pgdp = pgd_offset(mm, addr);
3337 
3338 	p4dp = p4d_offset(pgdp, addr);
3339 
3340 	if (p4d_none(*p4dp)) {
3341 		printf("No valid P4D\n");
3342 		return;
3343 	}
3344 
3345 	if (p4d_is_leaf(*p4dp)) {
3346 		format_pte(p4dp, p4d_val(*p4dp));
3347 		return;
3348 	}
3349 
3350 	printf("p4dp @ 0x%px = 0x%016lx\n", p4dp, p4d_val(*p4dp));
3351 
3352 	pudp = pud_offset(p4dp, addr);
3353 
3354 	if (pud_none(*pudp)) {
3355 		printf("No valid PUD\n");
3356 		return;
3357 	}
3358 
3359 	if (pud_is_leaf(*pudp)) {
3360 		format_pte(pudp, pud_val(*pudp));
3361 		return;
3362 	}
3363 
3364 	printf("pudp @ 0x%px = 0x%016lx\n", pudp, pud_val(*pudp));
3365 
3366 	pmdp = pmd_offset(pudp, addr);
3367 
3368 	if (pmd_none(*pmdp)) {
3369 		printf("No valid PMD\n");
3370 		return;
3371 	}
3372 
3373 	if (pmd_is_leaf(*pmdp)) {
3374 		format_pte(pmdp, pmd_val(*pmdp));
3375 		return;
3376 	}
3377 	printf("pmdp @ 0x%px = 0x%016lx\n", pmdp, pmd_val(*pmdp));
3378 
3379 	ptep = pte_offset_map(pmdp, addr);
3380 	if (pte_none(*ptep)) {
3381 		printf("no valid PTE\n");
3382 		return;
3383 	}
3384 
3385 	format_pte(ptep, pte_val(*ptep));
3386 
3387 	sync();
3388 	__delay(200);
3389 	catch_memory_errors = 0;
3390 }
3391 #else
3392 static void show_pte(unsigned long addr)
3393 {
3394 	printf("show_pte not yet implemented\n");
3395 }
3396 #endif /* CONFIG_PPC_BOOK3S_64 */
3397 
3398 static void show_tasks(void)
3399 {
3400 	unsigned long tskv;
3401 	struct task_struct *volatile tsk = NULL;
3402 
3403 	printf("     task_struct     ->thread.ksp    ->thread.regs    PID   PPID S  P CMD\n");
3404 
3405 	if (scanhex(&tskv))
3406 		tsk = (struct task_struct *)tskv;
3407 
3408 	if (setjmp(bus_error_jmp) != 0) {
3409 		catch_memory_errors = 0;
3410 		printf("*** Error dumping task %px\n", tsk);
3411 		return;
3412 	}
3413 
3414 	catch_memory_errors = 1;
3415 	sync();
3416 
3417 	if (tsk)
3418 		show_task(tsk);
3419 	else
3420 		for_each_process(tsk)
3421 			show_task(tsk);
3422 
3423 	sync();
3424 	__delay(200);
3425 	catch_memory_errors = 0;
3426 }
3427 
3428 static void proccall(void)
3429 {
3430 	unsigned long args[8];
3431 	unsigned long ret;
3432 	int i;
3433 	typedef unsigned long (*callfunc_t)(unsigned long, unsigned long,
3434 			unsigned long, unsigned long, unsigned long,
3435 			unsigned long, unsigned long, unsigned long);
3436 	callfunc_t func;
3437 
3438 	if (!scanhex(&adrs))
3439 		return;
3440 	if (termch != '\n')
3441 		termch = 0;
3442 	for (i = 0; i < 8; ++i)
3443 		args[i] = 0;
3444 	for (i = 0; i < 8; ++i) {
3445 		if (!scanhex(&args[i]) || termch == '\n')
3446 			break;
3447 		termch = 0;
3448 	}
3449 	func = (callfunc_t) adrs;
3450 	ret = 0;
3451 	if (setjmp(bus_error_jmp) == 0) {
3452 		catch_memory_errors = 1;
3453 		sync();
3454 		ret = func(args[0], args[1], args[2], args[3],
3455 			   args[4], args[5], args[6], args[7]);
3456 		sync();
3457 		printf("return value is 0x%lx\n", ret);
3458 	} else {
3459 		printf("*** %x exception occurred\n", fault_except);
3460 	}
3461 	catch_memory_errors = 0;
3462 }
3463 
3464 /* Input scanning routines */
3465 int
3466 skipbl(void)
3467 {
3468 	int c;
3469 
3470 	if( termch != 0 ){
3471 		c = termch;
3472 		termch = 0;
3473 	} else
3474 		c = inchar();
3475 	while( c == ' ' || c == '\t' )
3476 		c = inchar();
3477 	return c;
3478 }
3479 
3480 #define N_PTREGS	44
3481 static const char *regnames[N_PTREGS] = {
3482 	"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
3483 	"r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
3484 	"r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
3485 	"r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31",
3486 	"pc", "msr", "or3", "ctr", "lr", "xer", "ccr",
3487 #ifdef CONFIG_PPC64
3488 	"softe",
3489 #else
3490 	"mq",
3491 #endif
3492 	"trap", "dar", "dsisr", "res"
3493 };
3494 
3495 int
3496 scanhex(unsigned long *vp)
3497 {
3498 	int c, d;
3499 	unsigned long v;
3500 
3501 	c = skipbl();
3502 	if (c == '%') {
3503 		/* parse register name */
3504 		char regname[8];
3505 		int i;
3506 
3507 		for (i = 0; i < sizeof(regname) - 1; ++i) {
3508 			c = inchar();
3509 			if (!isalnum(c)) {
3510 				termch = c;
3511 				break;
3512 			}
3513 			regname[i] = c;
3514 		}
3515 		regname[i] = 0;
3516 		i = match_string(regnames, N_PTREGS, regname);
3517 		if (i < 0) {
3518 			printf("invalid register name '%%%s'\n", regname);
3519 			return 0;
3520 		}
3521 		if (xmon_regs == NULL) {
3522 			printf("regs not available\n");
3523 			return 0;
3524 		}
3525 		*vp = ((unsigned long *)xmon_regs)[i];
3526 		return 1;
3527 	}
3528 
3529 	/* skip leading "0x" if any */
3530 
3531 	if (c == '0') {
3532 		c = inchar();
3533 		if (c == 'x') {
3534 			c = inchar();
3535 		} else {
3536 			d = hexdigit(c);
3537 			if (d == EOF) {
3538 				termch = c;
3539 				*vp = 0;
3540 				return 1;
3541 			}
3542 		}
3543 	} else if (c == '$') {
3544 		int i;
3545 		for (i=0; i<63; i++) {
3546 			c = inchar();
3547 			if (isspace(c) || c == '\0') {
3548 				termch = c;
3549 				break;
3550 			}
3551 			tmpstr[i] = c;
3552 		}
3553 		tmpstr[i++] = 0;
3554 		*vp = 0;
3555 		if (setjmp(bus_error_jmp) == 0) {
3556 			catch_memory_errors = 1;
3557 			sync();
3558 			*vp = kallsyms_lookup_name(tmpstr);
3559 			sync();
3560 		}
3561 		catch_memory_errors = 0;
3562 		if (!(*vp)) {
3563 			printf("unknown symbol '%s'\n", tmpstr);
3564 			return 0;
3565 		}
3566 		return 1;
3567 	}
3568 
3569 	d = hexdigit(c);
3570 	if (d == EOF) {
3571 		termch = c;
3572 		return 0;
3573 	}
3574 	v = 0;
3575 	do {
3576 		v = (v << 4) + d;
3577 		c = inchar();
3578 		d = hexdigit(c);
3579 	} while (d != EOF);
3580 	termch = c;
3581 	*vp = v;
3582 	return 1;
3583 }
3584 
3585 static void
3586 scannl(void)
3587 {
3588 	int c;
3589 
3590 	c = termch;
3591 	termch = 0;
3592 	while( c != '\n' )
3593 		c = inchar();
3594 }
3595 
3596 static int hexdigit(int c)
3597 {
3598 	if( '0' <= c && c <= '9' )
3599 		return c - '0';
3600 	if( 'A' <= c && c <= 'F' )
3601 		return c - ('A' - 10);
3602 	if( 'a' <= c && c <= 'f' )
3603 		return c - ('a' - 10);
3604 	return EOF;
3605 }
3606 
3607 void
3608 getstring(char *s, int size)
3609 {
3610 	int c;
3611 
3612 	c = skipbl();
3613 	if (c == '\n') {
3614 		*s = 0;
3615 		return;
3616 	}
3617 
3618 	do {
3619 		if( size > 1 ){
3620 			*s++ = c;
3621 			--size;
3622 		}
3623 		c = inchar();
3624 	} while( c != ' ' && c != '\t' && c != '\n' );
3625 	termch = c;
3626 	*s = 0;
3627 }
3628 
3629 static char line[256];
3630 static char *lineptr;
3631 
3632 static void
3633 flush_input(void)
3634 {
3635 	lineptr = NULL;
3636 }
3637 
3638 static int
3639 inchar(void)
3640 {
3641 	if (lineptr == NULL || *lineptr == 0) {
3642 		if (xmon_gets(line, sizeof(line)) == NULL) {
3643 			lineptr = NULL;
3644 			return EOF;
3645 		}
3646 		lineptr = line;
3647 	}
3648 	return *lineptr++;
3649 }
3650 
3651 static void
3652 take_input(char *str)
3653 {
3654 	lineptr = str;
3655 }
3656 
3657 
3658 static void
3659 symbol_lookup(void)
3660 {
3661 	int type = inchar();
3662 	unsigned long addr, cpu;
3663 	void __percpu *ptr = NULL;
3664 	static char tmp[64];
3665 
3666 	switch (type) {
3667 	case 'a':
3668 		if (scanhex(&addr))
3669 			xmon_print_symbol(addr, ": ", "\n");
3670 		termch = 0;
3671 		break;
3672 	case 's':
3673 		getstring(tmp, 64);
3674 		if (setjmp(bus_error_jmp) == 0) {
3675 			catch_memory_errors = 1;
3676 			sync();
3677 			addr = kallsyms_lookup_name(tmp);
3678 			if (addr)
3679 				printf("%s: %lx\n", tmp, addr);
3680 			else
3681 				printf("Symbol '%s' not found.\n", tmp);
3682 			sync();
3683 		}
3684 		catch_memory_errors = 0;
3685 		termch = 0;
3686 		break;
3687 	case 'p':
3688 		getstring(tmp, 64);
3689 		if (setjmp(bus_error_jmp) == 0) {
3690 			catch_memory_errors = 1;
3691 			sync();
3692 			ptr = (void __percpu *)kallsyms_lookup_name(tmp);
3693 			sync();
3694 		}
3695 
3696 		if (ptr &&
3697 		    ptr >= (void __percpu *)__per_cpu_start &&
3698 		    ptr < (void __percpu *)__per_cpu_end)
3699 		{
3700 			if (scanhex(&cpu) && cpu < num_possible_cpus()) {
3701 				addr = (unsigned long)per_cpu_ptr(ptr, cpu);
3702 			} else {
3703 				cpu = raw_smp_processor_id();
3704 				addr = (unsigned long)this_cpu_ptr(ptr);
3705 			}
3706 
3707 			printf("%s for cpu 0x%lx: %lx\n", tmp, cpu, addr);
3708 		} else {
3709 			printf("Percpu symbol '%s' not found.\n", tmp);
3710 		}
3711 
3712 		catch_memory_errors = 0;
3713 		termch = 0;
3714 		break;
3715 	}
3716 }
3717 
3718 
3719 /* Print an address in numeric and symbolic form (if possible) */
3720 static void xmon_print_symbol(unsigned long address, const char *mid,
3721 			      const char *after)
3722 {
3723 	char *modname;
3724 	const char *volatile name = NULL;
3725 	unsigned long offset, size;
3726 
3727 	printf(REG, address);
3728 	if (setjmp(bus_error_jmp) == 0) {
3729 		catch_memory_errors = 1;
3730 		sync();
3731 		name = kallsyms_lookup(address, &size, &offset, &modname,
3732 				       tmpstr);
3733 		sync();
3734 		/* wait a little while to see if we get a machine check */
3735 		__delay(200);
3736 	}
3737 
3738 	catch_memory_errors = 0;
3739 
3740 	if (name) {
3741 		printf("%s%s+%#lx/%#lx", mid, name, offset, size);
3742 		if (modname)
3743 			printf(" [%s]", modname);
3744 	}
3745 	printf("%s", after);
3746 }
3747 
3748 #ifdef CONFIG_PPC_64S_HASH_MMU
3749 void dump_segments(void)
3750 {
3751 	int i;
3752 	unsigned long esid,vsid;
3753 	unsigned long llp;
3754 
3755 	printf("SLB contents of cpu 0x%x\n", smp_processor_id());
3756 
3757 	for (i = 0; i < mmu_slb_size; i++) {
3758 		asm volatile("slbmfee  %0,%1" : "=r" (esid) : "r" (i));
3759 		asm volatile("slbmfev  %0,%1" : "=r" (vsid) : "r" (i));
3760 
3761 		if (!esid && !vsid)
3762 			continue;
3763 
3764 		printf("%02d %016lx %016lx", i, esid, vsid);
3765 
3766 		if (!(esid & SLB_ESID_V)) {
3767 			printf("\n");
3768 			continue;
3769 		}
3770 
3771 		llp = vsid & SLB_VSID_LLP;
3772 		if (vsid & SLB_VSID_B_1T) {
3773 			printf("  1T  ESID=%9lx  VSID=%13lx LLP:%3lx \n",
3774 				GET_ESID_1T(esid),
3775 				(vsid & ~SLB_VSID_B) >> SLB_VSID_SHIFT_1T,
3776 				llp);
3777 		} else {
3778 			printf(" 256M ESID=%9lx  VSID=%13lx LLP:%3lx \n",
3779 				GET_ESID(esid),
3780 				(vsid & ~SLB_VSID_B) >> SLB_VSID_SHIFT,
3781 				llp);
3782 		}
3783 	}
3784 }
3785 #endif
3786 
3787 #ifdef CONFIG_PPC_BOOK3S_32
3788 void dump_segments(void)
3789 {
3790 	int i;
3791 
3792 	printf("sr0-15 =");
3793 	for (i = 0; i < 16; ++i)
3794 		printf(" %x", mfsr(i << 28));
3795 	printf("\n");
3796 }
3797 #endif
3798 
3799 #ifdef CONFIG_44x
3800 static void dump_tlb_44x(void)
3801 {
3802 	int i;
3803 
3804 	for (i = 0; i < PPC44x_TLB_SIZE; i++) {
3805 		unsigned long w0,w1,w2;
3806 		asm volatile("tlbre  %0,%1,0" : "=r" (w0) : "r" (i));
3807 		asm volatile("tlbre  %0,%1,1" : "=r" (w1) : "r" (i));
3808 		asm volatile("tlbre  %0,%1,2" : "=r" (w2) : "r" (i));
3809 		printf("[%02x] %08lx %08lx %08lx ", i, w0, w1, w2);
3810 		if (w0 & PPC44x_TLB_VALID) {
3811 			printf("V %08lx -> %01lx%08lx %c%c%c%c%c",
3812 			       w0 & PPC44x_TLB_EPN_MASK,
3813 			       w1 & PPC44x_TLB_ERPN_MASK,
3814 			       w1 & PPC44x_TLB_RPN_MASK,
3815 			       (w2 & PPC44x_TLB_W) ? 'W' : 'w',
3816 			       (w2 & PPC44x_TLB_I) ? 'I' : 'i',
3817 			       (w2 & PPC44x_TLB_M) ? 'M' : 'm',
3818 			       (w2 & PPC44x_TLB_G) ? 'G' : 'g',
3819 			       (w2 & PPC44x_TLB_E) ? 'E' : 'e');
3820 		}
3821 		printf("\n");
3822 	}
3823 }
3824 #endif /* CONFIG_44x */
3825 
3826 #ifdef CONFIG_PPC_BOOK3E
3827 static void dump_tlb_book3e(void)
3828 {
3829 	u32 mmucfg, pidmask, lpidmask;
3830 	u64 ramask;
3831 	int i, tlb, ntlbs, pidsz, lpidsz, rasz, lrat = 0;
3832 	int mmu_version;
3833 	static const char *pgsz_names[] = {
3834 		"  1K",
3835 		"  2K",
3836 		"  4K",
3837 		"  8K",
3838 		" 16K",
3839 		" 32K",
3840 		" 64K",
3841 		"128K",
3842 		"256K",
3843 		"512K",
3844 		"  1M",
3845 		"  2M",
3846 		"  4M",
3847 		"  8M",
3848 		" 16M",
3849 		" 32M",
3850 		" 64M",
3851 		"128M",
3852 		"256M",
3853 		"512M",
3854 		"  1G",
3855 		"  2G",
3856 		"  4G",
3857 		"  8G",
3858 		" 16G",
3859 		" 32G",
3860 		" 64G",
3861 		"128G",
3862 		"256G",
3863 		"512G",
3864 		"  1T",
3865 		"  2T",
3866 	};
3867 
3868 	/* Gather some infos about the MMU */
3869 	mmucfg = mfspr(SPRN_MMUCFG);
3870 	mmu_version = (mmucfg & 3) + 1;
3871 	ntlbs = ((mmucfg >> 2) & 3) + 1;
3872 	pidsz = ((mmucfg >> 6) & 0x1f) + 1;
3873 	lpidsz = (mmucfg >> 24) & 0xf;
3874 	rasz = (mmucfg >> 16) & 0x7f;
3875 	if ((mmu_version > 1) && (mmucfg & 0x10000))
3876 		lrat = 1;
3877 	printf("Book3E MMU MAV=%d.0,%d TLBs,%d-bit PID,%d-bit LPID,%d-bit RA\n",
3878 	       mmu_version, ntlbs, pidsz, lpidsz, rasz);
3879 	pidmask = (1ul << pidsz) - 1;
3880 	lpidmask = (1ul << lpidsz) - 1;
3881 	ramask = (1ull << rasz) - 1;
3882 
3883 	for (tlb = 0; tlb < ntlbs; tlb++) {
3884 		u32 tlbcfg;
3885 		int nent, assoc, new_cc = 1;
3886 		printf("TLB %d:\n------\n", tlb);
3887 		switch(tlb) {
3888 		case 0:
3889 			tlbcfg = mfspr(SPRN_TLB0CFG);
3890 			break;
3891 		case 1:
3892 			tlbcfg = mfspr(SPRN_TLB1CFG);
3893 			break;
3894 		case 2:
3895 			tlbcfg = mfspr(SPRN_TLB2CFG);
3896 			break;
3897 		case 3:
3898 			tlbcfg = mfspr(SPRN_TLB3CFG);
3899 			break;
3900 		default:
3901 			printf("Unsupported TLB number !\n");
3902 			continue;
3903 		}
3904 		nent = tlbcfg & 0xfff;
3905 		assoc = (tlbcfg >> 24) & 0xff;
3906 		for (i = 0; i < nent; i++) {
3907 			u32 mas0 = MAS0_TLBSEL(tlb);
3908 			u32 mas1 = MAS1_TSIZE(BOOK3E_PAGESZ_4K);
3909 			u64 mas2 = 0;
3910 			u64 mas7_mas3;
3911 			int esel = i, cc = i;
3912 
3913 			if (assoc != 0) {
3914 				cc = i / assoc;
3915 				esel = i % assoc;
3916 				mas2 = cc * 0x1000;
3917 			}
3918 
3919 			mas0 |= MAS0_ESEL(esel);
3920 			mtspr(SPRN_MAS0, mas0);
3921 			mtspr(SPRN_MAS1, mas1);
3922 			mtspr(SPRN_MAS2, mas2);
3923 			asm volatile("tlbre  0,0,0" : : : "memory");
3924 			mas1 = mfspr(SPRN_MAS1);
3925 			mas2 = mfspr(SPRN_MAS2);
3926 			mas7_mas3 = mfspr(SPRN_MAS7_MAS3);
3927 			if (assoc && (i % assoc) == 0)
3928 				new_cc = 1;
3929 			if (!(mas1 & MAS1_VALID))
3930 				continue;
3931 			if (assoc == 0)
3932 				printf("%04x- ", i);
3933 			else if (new_cc)
3934 				printf("%04x-%c", cc, 'A' + esel);
3935 			else
3936 				printf("    |%c", 'A' + esel);
3937 			new_cc = 0;
3938 			printf(" %016llx %04x %s %c%c AS%c",
3939 			       mas2 & ~0x3ffull,
3940 			       (mas1 >> 16) & 0x3fff,
3941 			       pgsz_names[(mas1 >> 7) & 0x1f],
3942 			       mas1 & MAS1_IND ? 'I' : ' ',
3943 			       mas1 & MAS1_IPROT ? 'P' : ' ',
3944 			       mas1 & MAS1_TS ? '1' : '0');
3945 			printf(" %c%c%c%c%c%c%c",
3946 			       mas2 & MAS2_X0 ? 'a' : ' ',
3947 			       mas2 & MAS2_X1 ? 'v' : ' ',
3948 			       mas2 & MAS2_W  ? 'w' : ' ',
3949 			       mas2 & MAS2_I  ? 'i' : ' ',
3950 			       mas2 & MAS2_M  ? 'm' : ' ',
3951 			       mas2 & MAS2_G  ? 'g' : ' ',
3952 			       mas2 & MAS2_E  ? 'e' : ' ');
3953 			printf(" %016llx", mas7_mas3 & ramask & ~0x7ffull);
3954 			if (mas1 & MAS1_IND)
3955 				printf(" %s\n",
3956 				       pgsz_names[(mas7_mas3 >> 1) & 0x1f]);
3957 			else
3958 				printf(" U%c%c%c S%c%c%c\n",
3959 				       mas7_mas3 & MAS3_UX ? 'x' : ' ',
3960 				       mas7_mas3 & MAS3_UW ? 'w' : ' ',
3961 				       mas7_mas3 & MAS3_UR ? 'r' : ' ',
3962 				       mas7_mas3 & MAS3_SX ? 'x' : ' ',
3963 				       mas7_mas3 & MAS3_SW ? 'w' : ' ',
3964 				       mas7_mas3 & MAS3_SR ? 'r' : ' ');
3965 		}
3966 	}
3967 }
3968 #endif /* CONFIG_PPC_BOOK3E */
3969 
3970 static void xmon_init(int enable)
3971 {
3972 	if (enable) {
3973 		__debugger = xmon;
3974 		__debugger_ipi = xmon_ipi;
3975 		__debugger_bpt = xmon_bpt;
3976 		__debugger_sstep = xmon_sstep;
3977 		__debugger_iabr_match = xmon_iabr_match;
3978 		__debugger_break_match = xmon_break_match;
3979 		__debugger_fault_handler = xmon_fault_handler;
3980 
3981 #ifdef CONFIG_PPC_PSERIES
3982 		/*
3983 		 * Get the token here to avoid trying to get a lock
3984 		 * during the crash, causing a deadlock.
3985 		 */
3986 		set_indicator_token = rtas_token("set-indicator");
3987 #endif
3988 	} else {
3989 		__debugger = NULL;
3990 		__debugger_ipi = NULL;
3991 		__debugger_bpt = NULL;
3992 		__debugger_sstep = NULL;
3993 		__debugger_iabr_match = NULL;
3994 		__debugger_break_match = NULL;
3995 		__debugger_fault_handler = NULL;
3996 	}
3997 }
3998 
3999 #ifdef CONFIG_MAGIC_SYSRQ
4000 static void sysrq_handle_xmon(int key)
4001 {
4002 	if (xmon_is_locked_down()) {
4003 		clear_all_bpt();
4004 		xmon_init(0);
4005 		return;
4006 	}
4007 	/* ensure xmon is enabled */
4008 	xmon_init(1);
4009 	debugger(get_irq_regs());
4010 	if (!xmon_on)
4011 		xmon_init(0);
4012 }
4013 
4014 static const struct sysrq_key_op sysrq_xmon_op = {
4015 	.handler =	sysrq_handle_xmon,
4016 	.help_msg =	"xmon(x)",
4017 	.action_msg =	"Entering xmon",
4018 };
4019 
4020 static int __init setup_xmon_sysrq(void)
4021 {
4022 	register_sysrq_key('x', &sysrq_xmon_op);
4023 	return 0;
4024 }
4025 device_initcall(setup_xmon_sysrq);
4026 #endif /* CONFIG_MAGIC_SYSRQ */
4027 
4028 static void clear_all_bpt(void)
4029 {
4030 	int i;
4031 
4032 	/* clear/unpatch all breakpoints */
4033 	remove_bpts();
4034 	remove_cpu_bpts();
4035 
4036 	/* Disable all breakpoints */
4037 	for (i = 0; i < NBPTS; ++i)
4038 		bpts[i].enabled = 0;
4039 
4040 	/* Clear any data or iabr breakpoints */
4041 	iabr = NULL;
4042 	for (i = 0; i < nr_wp_slots(); i++)
4043 		dabr[i].enabled = 0;
4044 }
4045 
4046 #ifdef CONFIG_DEBUG_FS
4047 static int xmon_dbgfs_set(void *data, u64 val)
4048 {
4049 	xmon_on = !!val;
4050 	xmon_init(xmon_on);
4051 
4052 	/* make sure all breakpoints removed when disabling */
4053 	if (!xmon_on) {
4054 		clear_all_bpt();
4055 		get_output_lock();
4056 		printf("xmon: All breakpoints cleared\n");
4057 		release_output_lock();
4058 	}
4059 
4060 	return 0;
4061 }
4062 
4063 static int xmon_dbgfs_get(void *data, u64 *val)
4064 {
4065 	*val = xmon_on;
4066 	return 0;
4067 }
4068 
4069 DEFINE_SIMPLE_ATTRIBUTE(xmon_dbgfs_ops, xmon_dbgfs_get,
4070 			xmon_dbgfs_set, "%llu\n");
4071 
4072 static int __init setup_xmon_dbgfs(void)
4073 {
4074 	debugfs_create_file("xmon", 0600, arch_debugfs_dir, NULL,
4075 			    &xmon_dbgfs_ops);
4076 	return 0;
4077 }
4078 device_initcall(setup_xmon_dbgfs);
4079 #endif /* CONFIG_DEBUG_FS */
4080 
4081 static int xmon_early __initdata;
4082 
4083 static int __init early_parse_xmon(char *p)
4084 {
4085 	if (xmon_is_locked_down()) {
4086 		xmon_init(0);
4087 		xmon_early = 0;
4088 		xmon_on = 0;
4089 	} else if (!p || strncmp(p, "early", 5) == 0) {
4090 		/* just "xmon" is equivalent to "xmon=early" */
4091 		xmon_init(1);
4092 		xmon_early = 1;
4093 		xmon_on = 1;
4094 	} else if (strncmp(p, "on", 2) == 0) {
4095 		xmon_init(1);
4096 		xmon_on = 1;
4097 	} else if (strncmp(p, "rw", 2) == 0) {
4098 		xmon_init(1);
4099 		xmon_on = 1;
4100 		xmon_is_ro = false;
4101 	} else if (strncmp(p, "ro", 2) == 0) {
4102 		xmon_init(1);
4103 		xmon_on = 1;
4104 		xmon_is_ro = true;
4105 	} else if (strncmp(p, "off", 3) == 0)
4106 		xmon_on = 0;
4107 	else
4108 		return 1;
4109 
4110 	return 0;
4111 }
4112 early_param("xmon", early_parse_xmon);
4113 
4114 void __init xmon_setup(void)
4115 {
4116 	if (xmon_on)
4117 		xmon_init(1);
4118 	if (xmon_early)
4119 		debugger(NULL);
4120 }
4121 
4122 #ifdef CONFIG_SPU_BASE
4123 
4124 struct spu_info {
4125 	struct spu *spu;
4126 	u64 saved_mfc_sr1_RW;
4127 	u32 saved_spu_runcntl_RW;
4128 	unsigned long dump_addr;
4129 	u8 stopped_ok;
4130 };
4131 
4132 #define XMON_NUM_SPUS	16	/* Enough for current hardware */
4133 
4134 static struct spu_info spu_info[XMON_NUM_SPUS];
4135 
4136 void __init xmon_register_spus(struct list_head *list)
4137 {
4138 	struct spu *spu;
4139 
4140 	list_for_each_entry(spu, list, full_list) {
4141 		if (spu->number >= XMON_NUM_SPUS) {
4142 			WARN_ON(1);
4143 			continue;
4144 		}
4145 
4146 		spu_info[spu->number].spu = spu;
4147 		spu_info[spu->number].stopped_ok = 0;
4148 		spu_info[spu->number].dump_addr = (unsigned long)
4149 				spu_info[spu->number].spu->local_store;
4150 	}
4151 }
4152 
4153 static void stop_spus(void)
4154 {
4155 	struct spu *spu;
4156 	volatile int i;
4157 	u64 tmp;
4158 
4159 	for (i = 0; i < XMON_NUM_SPUS; i++) {
4160 		if (!spu_info[i].spu)
4161 			continue;
4162 
4163 		if (setjmp(bus_error_jmp) == 0) {
4164 			catch_memory_errors = 1;
4165 			sync();
4166 
4167 			spu = spu_info[i].spu;
4168 
4169 			spu_info[i].saved_spu_runcntl_RW =
4170 				in_be32(&spu->problem->spu_runcntl_RW);
4171 
4172 			tmp = spu_mfc_sr1_get(spu);
4173 			spu_info[i].saved_mfc_sr1_RW = tmp;
4174 
4175 			tmp &= ~MFC_STATE1_MASTER_RUN_CONTROL_MASK;
4176 			spu_mfc_sr1_set(spu, tmp);
4177 
4178 			sync();
4179 			__delay(200);
4180 
4181 			spu_info[i].stopped_ok = 1;
4182 
4183 			printf("Stopped spu %.2d (was %s)\n", i,
4184 					spu_info[i].saved_spu_runcntl_RW ?
4185 					"running" : "stopped");
4186 		} else {
4187 			catch_memory_errors = 0;
4188 			printf("*** Error stopping spu %.2d\n", i);
4189 		}
4190 		catch_memory_errors = 0;
4191 	}
4192 }
4193 
4194 static void restart_spus(void)
4195 {
4196 	struct spu *spu;
4197 	volatile int i;
4198 
4199 	for (i = 0; i < XMON_NUM_SPUS; i++) {
4200 		if (!spu_info[i].spu)
4201 			continue;
4202 
4203 		if (!spu_info[i].stopped_ok) {
4204 			printf("*** Error, spu %d was not successfully stopped"
4205 					", not restarting\n", i);
4206 			continue;
4207 		}
4208 
4209 		if (setjmp(bus_error_jmp) == 0) {
4210 			catch_memory_errors = 1;
4211 			sync();
4212 
4213 			spu = spu_info[i].spu;
4214 			spu_mfc_sr1_set(spu, spu_info[i].saved_mfc_sr1_RW);
4215 			out_be32(&spu->problem->spu_runcntl_RW,
4216 					spu_info[i].saved_spu_runcntl_RW);
4217 
4218 			sync();
4219 			__delay(200);
4220 
4221 			printf("Restarted spu %.2d\n", i);
4222 		} else {
4223 			catch_memory_errors = 0;
4224 			printf("*** Error restarting spu %.2d\n", i);
4225 		}
4226 		catch_memory_errors = 0;
4227 	}
4228 }
4229 
4230 #define DUMP_WIDTH	23
4231 #define DUMP_VALUE(format, field, value)				\
4232 do {									\
4233 	if (setjmp(bus_error_jmp) == 0) {				\
4234 		catch_memory_errors = 1;				\
4235 		sync();							\
4236 		printf("  %-*s = "format"\n", DUMP_WIDTH,		\
4237 				#field, value);				\
4238 		sync();							\
4239 		__delay(200);						\
4240 	} else {							\
4241 		catch_memory_errors = 0;				\
4242 		printf("  %-*s = *** Error reading field.\n",		\
4243 					DUMP_WIDTH, #field);		\
4244 	}								\
4245 	catch_memory_errors = 0;					\
4246 } while (0)
4247 
4248 #define DUMP_FIELD(obj, format, field)	\
4249 	DUMP_VALUE(format, field, obj->field)
4250 
4251 static void dump_spu_fields(struct spu *spu)
4252 {
4253 	printf("Dumping spu fields at address %p:\n", spu);
4254 
4255 	DUMP_FIELD(spu, "0x%x", number);
4256 	DUMP_FIELD(spu, "%s", name);
4257 	DUMP_FIELD(spu, "0x%lx", local_store_phys);
4258 	DUMP_FIELD(spu, "0x%p", local_store);
4259 	DUMP_FIELD(spu, "0x%lx", ls_size);
4260 	DUMP_FIELD(spu, "0x%x", node);
4261 	DUMP_FIELD(spu, "0x%lx", flags);
4262 	DUMP_FIELD(spu, "%llu", class_0_pending);
4263 	DUMP_FIELD(spu, "0x%llx", class_0_dar);
4264 	DUMP_FIELD(spu, "0x%llx", class_1_dar);
4265 	DUMP_FIELD(spu, "0x%llx", class_1_dsisr);
4266 	DUMP_FIELD(spu, "0x%x", irqs[0]);
4267 	DUMP_FIELD(spu, "0x%x", irqs[1]);
4268 	DUMP_FIELD(spu, "0x%x", irqs[2]);
4269 	DUMP_FIELD(spu, "0x%x", slb_replace);
4270 	DUMP_FIELD(spu, "%d", pid);
4271 	DUMP_FIELD(spu, "0x%p", mm);
4272 	DUMP_FIELD(spu, "0x%p", ctx);
4273 	DUMP_FIELD(spu, "0x%p", rq);
4274 	DUMP_FIELD(spu, "0x%llx", timestamp);
4275 	DUMP_FIELD(spu, "0x%lx", problem_phys);
4276 	DUMP_FIELD(spu, "0x%p", problem);
4277 	DUMP_VALUE("0x%x", problem->spu_runcntl_RW,
4278 			in_be32(&spu->problem->spu_runcntl_RW));
4279 	DUMP_VALUE("0x%x", problem->spu_status_R,
4280 			in_be32(&spu->problem->spu_status_R));
4281 	DUMP_VALUE("0x%x", problem->spu_npc_RW,
4282 			in_be32(&spu->problem->spu_npc_RW));
4283 	DUMP_FIELD(spu, "0x%p", priv2);
4284 	DUMP_FIELD(spu, "0x%p", pdata);
4285 }
4286 
4287 static int spu_inst_dump(unsigned long adr, long count, int praddr)
4288 {
4289 	return generic_inst_dump(adr, count, praddr, print_insn_spu);
4290 }
4291 
4292 static void dump_spu_ls(unsigned long num, int subcmd)
4293 {
4294 	unsigned long offset, addr, ls_addr;
4295 
4296 	if (setjmp(bus_error_jmp) == 0) {
4297 		catch_memory_errors = 1;
4298 		sync();
4299 		ls_addr = (unsigned long)spu_info[num].spu->local_store;
4300 		sync();
4301 		__delay(200);
4302 	} else {
4303 		catch_memory_errors = 0;
4304 		printf("*** Error: accessing spu info for spu %ld\n", num);
4305 		return;
4306 	}
4307 	catch_memory_errors = 0;
4308 
4309 	if (scanhex(&offset))
4310 		addr = ls_addr + offset;
4311 	else
4312 		addr = spu_info[num].dump_addr;
4313 
4314 	if (addr >= ls_addr + LS_SIZE) {
4315 		printf("*** Error: address outside of local store\n");
4316 		return;
4317 	}
4318 
4319 	switch (subcmd) {
4320 	case 'i':
4321 		addr += spu_inst_dump(addr, 16, 1);
4322 		last_cmd = "sdi\n";
4323 		break;
4324 	default:
4325 		prdump(addr, 64);
4326 		addr += 64;
4327 		last_cmd = "sd\n";
4328 		break;
4329 	}
4330 
4331 	spu_info[num].dump_addr = addr;
4332 }
4333 
4334 static int do_spu_cmd(void)
4335 {
4336 	static unsigned long num = 0;
4337 	int cmd, subcmd = 0;
4338 
4339 	cmd = inchar();
4340 	switch (cmd) {
4341 	case 's':
4342 		stop_spus();
4343 		break;
4344 	case 'r':
4345 		restart_spus();
4346 		break;
4347 	case 'd':
4348 		subcmd = inchar();
4349 		if (isxdigit(subcmd) || subcmd == '\n')
4350 			termch = subcmd;
4351 		fallthrough;
4352 	case 'f':
4353 		scanhex(&num);
4354 		if (num >= XMON_NUM_SPUS || !spu_info[num].spu) {
4355 			printf("*** Error: invalid spu number\n");
4356 			return 0;
4357 		}
4358 
4359 		switch (cmd) {
4360 		case 'f':
4361 			dump_spu_fields(spu_info[num].spu);
4362 			break;
4363 		default:
4364 			dump_spu_ls(num, subcmd);
4365 			break;
4366 		}
4367 
4368 		break;
4369 	default:
4370 		return -1;
4371 	}
4372 
4373 	return 0;
4374 }
4375 #else /* ! CONFIG_SPU_BASE */
4376 static int do_spu_cmd(void)
4377 {
4378 	return -1;
4379 }
4380 #endif
4381