xref: /openbmc/linux/arch/ia64/kernel/mca.c (revision 6197e5b7)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * File:	mca.c
4  * Purpose:	Generic MCA handling layer
5  *
6  * Copyright (C) 2003 Hewlett-Packard Co
7  *	David Mosberger-Tang <davidm@hpl.hp.com>
8  *
9  * Copyright (C) 2002 Dell Inc.
10  * Copyright (C) Matt Domsch <Matt_Domsch@dell.com>
11  *
12  * Copyright (C) 2002 Intel
13  * Copyright (C) Jenna Hall <jenna.s.hall@intel.com>
14  *
15  * Copyright (C) 2001 Intel
16  * Copyright (C) Fred Lewis <frederick.v.lewis@intel.com>
17  *
18  * Copyright (C) 2000 Intel
19  * Copyright (C) Chuck Fleckenstein <cfleck@co.intel.com>
20  *
21  * Copyright (C) 1999, 2004-2008 Silicon Graphics, Inc.
22  * Copyright (C) Vijay Chander <vijay@engr.sgi.com>
23  *
24  * Copyright (C) 2006 FUJITSU LIMITED
25  * Copyright (C) Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
26  *
27  * 2000-03-29 Chuck Fleckenstein <cfleck@co.intel.com>
28  *	      Fixed PAL/SAL update issues, began MCA bug fixes, logging issues,
29  *	      added min save state dump, added INIT handler.
30  *
31  * 2001-01-03 Fred Lewis <frederick.v.lewis@intel.com>
32  *	      Added setup of CMCI and CPEI IRQs, logging of corrected platform
33  *	      errors, completed code for logging of corrected & uncorrected
34  *	      machine check errors, and updated for conformance with Nov. 2000
35  *	      revision of the SAL 3.0 spec.
36  *
37  * 2002-01-04 Jenna Hall <jenna.s.hall@intel.com>
38  *	      Aligned MCA stack to 16 bytes, added platform vs. CPU error flag,
39  *	      set SAL default return values, changed error record structure to
40  *	      linked list, added init call to sal_get_state_info_size().
41  *
42  * 2002-03-25 Matt Domsch <Matt_Domsch@dell.com>
43  *	      GUID cleanups.
44  *
45  * 2003-04-15 David Mosberger-Tang <davidm@hpl.hp.com>
46  *	      Added INIT backtrace support.
47  *
48  * 2003-12-08 Keith Owens <kaos@sgi.com>
49  *	      smp_call_function() must not be called from interrupt context
50  *	      (can deadlock on tasklist_lock).
51  *	      Use keventd to call smp_call_function().
52  *
53  * 2004-02-01 Keith Owens <kaos@sgi.com>
54  *	      Avoid deadlock when using printk() for MCA and INIT records.
55  *	      Delete all record printing code, moved to salinfo_decode in user
56  *	      space.  Mark variables and functions static where possible.
57  *	      Delete dead variables and functions.  Reorder to remove the need
58  *	      for forward declarations and to consolidate related code.
59  *
60  * 2005-08-12 Keith Owens <kaos@sgi.com>
61  *	      Convert MCA/INIT handlers to use per event stacks and SAL/OS
62  *	      state.
63  *
64  * 2005-10-07 Keith Owens <kaos@sgi.com>
65  *	      Add notify_die() hooks.
66  *
67  * 2006-09-15 Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
68  *	      Add printing support for MCA/INIT.
69  *
70  * 2007-04-27 Russ Anderson <rja@sgi.com>
71  *	      Support multiple cpus going through OS_MCA in the same event.
72  */
73 #include <linux/jiffies.h>
74 #include <linux/types.h>
75 #include <linux/init.h>
76 #include <linux/sched/signal.h>
77 #include <linux/sched/debug.h>
78 #include <linux/sched/task.h>
79 #include <linux/interrupt.h>
80 #include <linux/irq.h>
81 #include <linux/memblock.h>
82 #include <linux/acpi.h>
83 #include <linux/timer.h>
84 #include <linux/module.h>
85 #include <linux/kernel.h>
86 #include <linux/smp.h>
87 #include <linux/workqueue.h>
88 #include <linux/cpumask.h>
89 #include <linux/kdebug.h>
90 #include <linux/cpu.h>
91 #include <linux/gfp.h>
92 
93 #include <asm/delay.h>
94 #include <asm/efi.h>
95 #include <asm/meminit.h>
96 #include <asm/page.h>
97 #include <asm/ptrace.h>
98 #include <asm/sal.h>
99 #include <asm/mca.h>
100 #include <asm/kexec.h>
101 
102 #include <asm/irq.h>
103 #include <asm/hw_irq.h>
104 #include <asm/tlb.h>
105 
106 #include "mca_drv.h"
107 #include "entry.h"
108 #include "irq.h"
109 
110 #if defined(IA64_MCA_DEBUG_INFO)
111 # define IA64_MCA_DEBUG(fmt...)	printk(fmt)
112 #else
113 # define IA64_MCA_DEBUG(fmt...)
114 #endif
115 
116 #define NOTIFY_INIT(event, regs, arg, spin)				\
117 do {									\
118 	if ((notify_die((event), "INIT", (regs), (arg), 0, 0)		\
119 			== NOTIFY_STOP) && ((spin) == 1))		\
120 		ia64_mca_spin(__func__);				\
121 } while (0)
122 
123 #define NOTIFY_MCA(event, regs, arg, spin)				\
124 do {									\
125 	if ((notify_die((event), "MCA", (regs), (arg), 0, 0)		\
126 			== NOTIFY_STOP) && ((spin) == 1))		\
127 		ia64_mca_spin(__func__);				\
128 } while (0)
129 
130 /* Used by mca_asm.S */
131 DEFINE_PER_CPU(u64, ia64_mca_data); /* == __per_cpu_mca[smp_processor_id()] */
132 DEFINE_PER_CPU(u64, ia64_mca_per_cpu_pte); /* PTE to map per-CPU area */
133 DEFINE_PER_CPU(u64, ia64_mca_pal_pte);	    /* PTE to map PAL code */
134 DEFINE_PER_CPU(u64, ia64_mca_pal_base);    /* vaddr PAL code granule */
135 DEFINE_PER_CPU(u64, ia64_mca_tr_reload);   /* Flag for TR reload */
136 
137 unsigned long __per_cpu_mca[NR_CPUS];
138 
139 /* In mca_asm.S */
140 extern void			ia64_os_init_dispatch_monarch (void);
141 extern void			ia64_os_init_dispatch_slave (void);
142 
143 static int monarch_cpu = -1;
144 
145 static ia64_mc_info_t		ia64_mc_info;
146 
147 #define MAX_CPE_POLL_INTERVAL (15*60*HZ) /* 15 minutes */
148 #define MIN_CPE_POLL_INTERVAL (2*60*HZ)  /* 2 minutes */
149 #define CMC_POLL_INTERVAL     (1*60*HZ)  /* 1 minute */
150 #define CPE_HISTORY_LENGTH    5
151 #define CMC_HISTORY_LENGTH    5
152 
153 static struct timer_list cpe_poll_timer;
154 static struct timer_list cmc_poll_timer;
155 /*
156  * This variable tells whether we are currently in polling mode.
157  * Start with this in the wrong state so we won't play w/ timers
158  * before the system is ready.
159  */
160 static int cmc_polling_enabled = 1;
161 
162 /*
163  * Clearing this variable prevents CPE polling from getting activated
164  * in mca_late_init.  Use it if your system doesn't provide a CPEI,
165  * but encounters problems retrieving CPE logs.  This should only be
166  * necessary for debugging.
167  */
168 static int cpe_poll_enabled = 1;
169 
170 extern void salinfo_log_wakeup(int type, u8 *buffer, u64 size, int irqsafe);
171 
172 static int mca_init __initdata;
173 
174 /*
175  * limited & delayed printing support for MCA/INIT handler
176  */
177 
178 #define mprintk(fmt...) ia64_mca_printk(fmt)
179 
180 #define MLOGBUF_SIZE (512+256*NR_CPUS)
181 #define MLOGBUF_MSGMAX 256
182 static char mlogbuf[MLOGBUF_SIZE];
183 static DEFINE_SPINLOCK(mlogbuf_wlock);	/* mca context only */
184 static DEFINE_SPINLOCK(mlogbuf_rlock);	/* normal context only */
185 static unsigned long mlogbuf_start;
186 static unsigned long mlogbuf_end;
187 static unsigned int mlogbuf_finished = 0;
188 static unsigned long mlogbuf_timestamp = 0;
189 
190 static int loglevel_save = -1;
191 #define BREAK_LOGLEVEL(__console_loglevel)		\
192 	oops_in_progress = 1;				\
193 	if (loglevel_save < 0)				\
194 		loglevel_save = __console_loglevel;	\
195 	__console_loglevel = 15;
196 
197 #define RESTORE_LOGLEVEL(__console_loglevel)		\
198 	if (loglevel_save >= 0) {			\
199 		__console_loglevel = loglevel_save;	\
200 		loglevel_save = -1;			\
201 	}						\
202 	mlogbuf_finished = 0;				\
203 	oops_in_progress = 0;
204 
205 /*
206  * Push messages into buffer, print them later if not urgent.
207  */
208 void ia64_mca_printk(const char *fmt, ...)
209 {
210 	va_list args;
211 	int printed_len;
212 	char temp_buf[MLOGBUF_MSGMAX];
213 	char *p;
214 
215 	va_start(args, fmt);
216 	printed_len = vscnprintf(temp_buf, sizeof(temp_buf), fmt, args);
217 	va_end(args);
218 
219 	/* Copy the output into mlogbuf */
220 	if (oops_in_progress) {
221 		/* mlogbuf was abandoned, use printk directly instead. */
222 		printk("%s", temp_buf);
223 	} else {
224 		spin_lock(&mlogbuf_wlock);
225 		for (p = temp_buf; *p; p++) {
226 			unsigned long next = (mlogbuf_end + 1) % MLOGBUF_SIZE;
227 			if (next != mlogbuf_start) {
228 				mlogbuf[mlogbuf_end] = *p;
229 				mlogbuf_end = next;
230 			} else {
231 				/* buffer full */
232 				break;
233 			}
234 		}
235 		mlogbuf[mlogbuf_end] = '\0';
236 		spin_unlock(&mlogbuf_wlock);
237 	}
238 }
239 EXPORT_SYMBOL(ia64_mca_printk);
240 
241 /*
242  * Print buffered messages.
243  *  NOTE: call this after returning normal context. (ex. from salinfod)
244  */
245 void ia64_mlogbuf_dump(void)
246 {
247 	char temp_buf[MLOGBUF_MSGMAX];
248 	char *p;
249 	unsigned long index;
250 	unsigned long flags;
251 	unsigned int printed_len;
252 
253 	/* Get output from mlogbuf */
254 	while (mlogbuf_start != mlogbuf_end) {
255 		temp_buf[0] = '\0';
256 		p = temp_buf;
257 		printed_len = 0;
258 
259 		spin_lock_irqsave(&mlogbuf_rlock, flags);
260 
261 		index = mlogbuf_start;
262 		while (index != mlogbuf_end) {
263 			*p = mlogbuf[index];
264 			index = (index + 1) % MLOGBUF_SIZE;
265 			if (!*p)
266 				break;
267 			p++;
268 			if (++printed_len >= MLOGBUF_MSGMAX - 1)
269 				break;
270 		}
271 		*p = '\0';
272 		if (temp_buf[0])
273 			printk("%s", temp_buf);
274 		mlogbuf_start = index;
275 
276 		mlogbuf_timestamp = 0;
277 		spin_unlock_irqrestore(&mlogbuf_rlock, flags);
278 	}
279 }
280 EXPORT_SYMBOL(ia64_mlogbuf_dump);
281 
282 /*
283  * Call this if system is going to down or if immediate flushing messages to
284  * console is required. (ex. recovery was failed, crash dump is going to be
285  * invoked, long-wait rendezvous etc.)
286  *  NOTE: this should be called from monarch.
287  */
288 static void ia64_mlogbuf_finish(int wait)
289 {
290 	BREAK_LOGLEVEL(console_loglevel);
291 
292 	spin_lock_init(&mlogbuf_rlock);
293 	ia64_mlogbuf_dump();
294 	printk(KERN_EMERG "mlogbuf_finish: printing switched to urgent mode, "
295 		"MCA/INIT might be dodgy or fail.\n");
296 
297 	if (!wait)
298 		return;
299 
300 	/* wait for console */
301 	printk("Delaying for 5 seconds...\n");
302 	udelay(5*1000000);
303 
304 	mlogbuf_finished = 1;
305 }
306 
307 /*
308  * Print buffered messages from INIT context.
309  */
310 static void ia64_mlogbuf_dump_from_init(void)
311 {
312 	if (mlogbuf_finished)
313 		return;
314 
315 	if (mlogbuf_timestamp &&
316 			time_before(jiffies, mlogbuf_timestamp + 30 * HZ)) {
317 		printk(KERN_ERR "INIT: mlogbuf_dump is interrupted by INIT "
318 			" and the system seems to be messed up.\n");
319 		ia64_mlogbuf_finish(0);
320 		return;
321 	}
322 
323 	if (!spin_trylock(&mlogbuf_rlock)) {
324 		printk(KERN_ERR "INIT: mlogbuf_dump is interrupted by INIT. "
325 			"Generated messages other than stack dump will be "
326 			"buffered to mlogbuf and will be printed later.\n");
327 		printk(KERN_ERR "INIT: If messages would not printed after "
328 			"this INIT, wait 30sec and assert INIT again.\n");
329 		if (!mlogbuf_timestamp)
330 			mlogbuf_timestamp = jiffies;
331 		return;
332 	}
333 	spin_unlock(&mlogbuf_rlock);
334 	ia64_mlogbuf_dump();
335 }
336 
337 static inline void
338 ia64_mca_spin(const char *func)
339 {
340 	if (monarch_cpu == smp_processor_id())
341 		ia64_mlogbuf_finish(0);
342 	mprintk(KERN_EMERG "%s: spinning here, not returning to SAL\n", func);
343 	while (1)
344 		cpu_relax();
345 }
346 /*
347  * IA64_MCA log support
348  */
349 #define IA64_MAX_LOGS		2	/* Double-buffering for nested MCAs */
350 #define IA64_MAX_LOG_TYPES      4   /* MCA, INIT, CMC, CPE */
351 
352 typedef struct ia64_state_log_s
353 {
354 	spinlock_t	isl_lock;
355 	int		isl_index;
356 	unsigned long	isl_count;
357 	ia64_err_rec_t  *isl_log[IA64_MAX_LOGS]; /* need space to store header + error log */
358 } ia64_state_log_t;
359 
360 static ia64_state_log_t ia64_state_log[IA64_MAX_LOG_TYPES];
361 
362 #define IA64_LOG_LOCK_INIT(it) spin_lock_init(&ia64_state_log[it].isl_lock)
363 #define IA64_LOG_LOCK(it)      spin_lock_irqsave(&ia64_state_log[it].isl_lock, s)
364 #define IA64_LOG_UNLOCK(it)    spin_unlock_irqrestore(&ia64_state_log[it].isl_lock,s)
365 #define IA64_LOG_NEXT_INDEX(it)    ia64_state_log[it].isl_index
366 #define IA64_LOG_CURR_INDEX(it)    1 - ia64_state_log[it].isl_index
367 #define IA64_LOG_INDEX_INC(it) \
368     {ia64_state_log[it].isl_index = 1 - ia64_state_log[it].isl_index; \
369     ia64_state_log[it].isl_count++;}
370 #define IA64_LOG_INDEX_DEC(it) \
371     ia64_state_log[it].isl_index = 1 - ia64_state_log[it].isl_index
372 #define IA64_LOG_NEXT_BUFFER(it)   (void *)((ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)]))
373 #define IA64_LOG_CURR_BUFFER(it)   (void *)((ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)]))
374 #define IA64_LOG_COUNT(it)         ia64_state_log[it].isl_count
375 
376 static inline void ia64_log_allocate(int it, u64 size)
377 {
378 	ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)] =
379 		(ia64_err_rec_t *)memblock_alloc(size, SMP_CACHE_BYTES);
380 	if (!ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)])
381 		panic("%s: Failed to allocate %llu bytes\n", __func__, size);
382 
383 	ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)] =
384 		(ia64_err_rec_t *)memblock_alloc(size, SMP_CACHE_BYTES);
385 	if (!ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)])
386 		panic("%s: Failed to allocate %llu bytes\n", __func__, size);
387 }
388 
389 /*
390  * ia64_log_init
391  *	Reset the OS ia64 log buffer
392  * Inputs   :   info_type   (SAL_INFO_TYPE_{MCA,INIT,CMC,CPE})
393  * Outputs	:	None
394  */
395 static void __init
396 ia64_log_init(int sal_info_type)
397 {
398 	u64	max_size = 0;
399 
400 	IA64_LOG_NEXT_INDEX(sal_info_type) = 0;
401 	IA64_LOG_LOCK_INIT(sal_info_type);
402 
403 	// SAL will tell us the maximum size of any error record of this type
404 	max_size = ia64_sal_get_state_info_size(sal_info_type);
405 	if (!max_size)
406 		/* alloc_bootmem() doesn't like zero-sized allocations! */
407 		return;
408 
409 	// set up OS data structures to hold error info
410 	ia64_log_allocate(sal_info_type, max_size);
411 }
412 
413 /*
414  * ia64_log_get
415  *
416  *	Get the current MCA log from SAL and copy it into the OS log buffer.
417  *
418  *  Inputs  :   info_type   (SAL_INFO_TYPE_{MCA,INIT,CMC,CPE})
419  *              irq_safe    whether you can use printk at this point
420  *  Outputs :   size        (total record length)
421  *              *buffer     (ptr to error record)
422  *
423  */
424 static u64
425 ia64_log_get(int sal_info_type, u8 **buffer, int irq_safe)
426 {
427 	sal_log_record_header_t     *log_buffer;
428 	u64                         total_len = 0;
429 	unsigned long               s;
430 
431 	IA64_LOG_LOCK(sal_info_type);
432 
433 	/* Get the process state information */
434 	log_buffer = IA64_LOG_NEXT_BUFFER(sal_info_type);
435 
436 	total_len = ia64_sal_get_state_info(sal_info_type, (u64 *)log_buffer);
437 
438 	if (total_len) {
439 		IA64_LOG_INDEX_INC(sal_info_type);
440 		IA64_LOG_UNLOCK(sal_info_type);
441 		if (irq_safe) {
442 			IA64_MCA_DEBUG("%s: SAL error record type %d retrieved. Record length = %ld\n",
443 				       __func__, sal_info_type, total_len);
444 		}
445 		*buffer = (u8 *) log_buffer;
446 		return total_len;
447 	} else {
448 		IA64_LOG_UNLOCK(sal_info_type);
449 		return 0;
450 	}
451 }
452 
453 /*
454  *  ia64_mca_log_sal_error_record
455  *
456  *  This function retrieves a specified error record type from SAL
457  *  and wakes up any processes waiting for error records.
458  *
459  *  Inputs  :   sal_info_type   (Type of error record MCA/CMC/CPE)
460  *              FIXME: remove MCA and irq_safe.
461  */
462 static void
463 ia64_mca_log_sal_error_record(int sal_info_type)
464 {
465 	u8 *buffer;
466 	sal_log_record_header_t *rh;
467 	u64 size;
468 	int irq_safe = sal_info_type != SAL_INFO_TYPE_MCA;
469 #ifdef IA64_MCA_DEBUG_INFO
470 	static const char * const rec_name[] = { "MCA", "INIT", "CMC", "CPE" };
471 #endif
472 
473 	size = ia64_log_get(sal_info_type, &buffer, irq_safe);
474 	if (!size)
475 		return;
476 
477 	salinfo_log_wakeup(sal_info_type, buffer, size, irq_safe);
478 
479 	if (irq_safe)
480 		IA64_MCA_DEBUG("CPU %d: SAL log contains %s error record\n",
481 			smp_processor_id(),
482 			sal_info_type < ARRAY_SIZE(rec_name) ? rec_name[sal_info_type] : "UNKNOWN");
483 
484 	/* Clear logs from corrected errors in case there's no user-level logger */
485 	rh = (sal_log_record_header_t *)buffer;
486 	if (rh->severity == sal_log_severity_corrected)
487 		ia64_sal_clear_state_info(sal_info_type);
488 }
489 
490 /*
491  * search_mca_table
492  *  See if the MCA surfaced in an instruction range
493  *  that has been tagged as recoverable.
494  *
495  *  Inputs
496  *	first	First address range to check
497  *	last	Last address range to check
498  *	ip	Instruction pointer, address we are looking for
499  *
500  * Return value:
501  *      1 on Success (in the table)/ 0 on Failure (not in the  table)
502  */
503 int
504 search_mca_table (const struct mca_table_entry *first,
505                 const struct mca_table_entry *last,
506                 unsigned long ip)
507 {
508         const struct mca_table_entry *curr;
509         u64 curr_start, curr_end;
510 
511         curr = first;
512         while (curr <= last) {
513                 curr_start = (u64) &curr->start_addr + curr->start_addr;
514                 curr_end = (u64) &curr->end_addr + curr->end_addr;
515 
516                 if ((ip >= curr_start) && (ip <= curr_end)) {
517                         return 1;
518                 }
519                 curr++;
520         }
521         return 0;
522 }
523 
524 /* Given an address, look for it in the mca tables. */
525 int mca_recover_range(unsigned long addr)
526 {
527 	extern struct mca_table_entry __start___mca_table[];
528 	extern struct mca_table_entry __stop___mca_table[];
529 
530 	return search_mca_table(__start___mca_table, __stop___mca_table-1, addr);
531 }
532 EXPORT_SYMBOL_GPL(mca_recover_range);
533 
534 int cpe_vector = -1;
535 int ia64_cpe_irq = -1;
536 
537 static irqreturn_t
538 ia64_mca_cpe_int_handler (int cpe_irq, void *arg)
539 {
540 	static unsigned long	cpe_history[CPE_HISTORY_LENGTH];
541 	static int		index;
542 	static DEFINE_SPINLOCK(cpe_history_lock);
543 
544 	IA64_MCA_DEBUG("%s: received interrupt vector = %#x on CPU %d\n",
545 		       __func__, cpe_irq, smp_processor_id());
546 
547 	/* SAL spec states this should run w/ interrupts enabled */
548 	local_irq_enable();
549 
550 	spin_lock(&cpe_history_lock);
551 	if (!cpe_poll_enabled && cpe_vector >= 0) {
552 
553 		int i, count = 1; /* we know 1 happened now */
554 		unsigned long now = jiffies;
555 
556 		for (i = 0; i < CPE_HISTORY_LENGTH; i++) {
557 			if (now - cpe_history[i] <= HZ)
558 				count++;
559 		}
560 
561 		IA64_MCA_DEBUG(KERN_INFO "CPE threshold %d/%d\n", count, CPE_HISTORY_LENGTH);
562 		if (count >= CPE_HISTORY_LENGTH) {
563 
564 			cpe_poll_enabled = 1;
565 			spin_unlock(&cpe_history_lock);
566 			disable_irq_nosync(local_vector_to_irq(IA64_CPE_VECTOR));
567 
568 			/*
569 			 * Corrected errors will still be corrected, but
570 			 * make sure there's a log somewhere that indicates
571 			 * something is generating more than we can handle.
572 			 */
573 			printk(KERN_WARNING "WARNING: Switching to polling CPE handler; error records may be lost\n");
574 
575 			mod_timer(&cpe_poll_timer, jiffies + MIN_CPE_POLL_INTERVAL);
576 
577 			/* lock already released, get out now */
578 			goto out;
579 		} else {
580 			cpe_history[index++] = now;
581 			if (index == CPE_HISTORY_LENGTH)
582 				index = 0;
583 		}
584 	}
585 	spin_unlock(&cpe_history_lock);
586 out:
587 	/* Get the CPE error record and log it */
588 	ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CPE);
589 
590 	local_irq_disable();
591 
592 	return IRQ_HANDLED;
593 }
594 
595 /*
596  * ia64_mca_register_cpev
597  *
598  *  Register the corrected platform error vector with SAL.
599  *
600  *  Inputs
601  *      cpev        Corrected Platform Error Vector number
602  *
603  *  Outputs
604  *      None
605  */
606 void
607 ia64_mca_register_cpev (int cpev)
608 {
609 	/* Register the CPE interrupt vector with SAL */
610 	struct ia64_sal_retval isrv;
611 
612 	isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_CPE_INT, SAL_MC_PARAM_MECHANISM_INT, cpev, 0, 0);
613 	if (isrv.status) {
614 		printk(KERN_ERR "Failed to register Corrected Platform "
615 		       "Error interrupt vector with SAL (status %ld)\n", isrv.status);
616 		return;
617 	}
618 
619 	IA64_MCA_DEBUG("%s: corrected platform error "
620 		       "vector %#x registered\n", __func__, cpev);
621 }
622 
623 /*
624  * ia64_mca_cmc_vector_setup
625  *
626  *  Setup the corrected machine check vector register in the processor.
627  *  (The interrupt is masked on boot. ia64_mca_late_init unmask this.)
628  *  This function is invoked on a per-processor basis.
629  *
630  * Inputs
631  *      None
632  *
633  * Outputs
634  *	None
635  */
636 void
637 ia64_mca_cmc_vector_setup (void)
638 {
639 	cmcv_reg_t	cmcv;
640 
641 	cmcv.cmcv_regval	= 0;
642 	cmcv.cmcv_mask		= 1;        /* Mask/disable interrupt at first */
643 	cmcv.cmcv_vector	= IA64_CMC_VECTOR;
644 	ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
645 
646 	IA64_MCA_DEBUG("%s: CPU %d corrected machine check vector %#x registered.\n",
647 		       __func__, smp_processor_id(), IA64_CMC_VECTOR);
648 
649 	IA64_MCA_DEBUG("%s: CPU %d CMCV = %#016lx\n",
650 		       __func__, smp_processor_id(), ia64_getreg(_IA64_REG_CR_CMCV));
651 }
652 
653 /*
654  * ia64_mca_cmc_vector_disable
655  *
656  *  Mask the corrected machine check vector register in the processor.
657  *  This function is invoked on a per-processor basis.
658  *
659  * Inputs
660  *      dummy(unused)
661  *
662  * Outputs
663  *	None
664  */
665 static void
666 ia64_mca_cmc_vector_disable (void *dummy)
667 {
668 	cmcv_reg_t	cmcv;
669 
670 	cmcv.cmcv_regval = ia64_getreg(_IA64_REG_CR_CMCV);
671 
672 	cmcv.cmcv_mask = 1; /* Mask/disable interrupt */
673 	ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
674 
675 	IA64_MCA_DEBUG("%s: CPU %d corrected machine check vector %#x disabled.\n",
676 		       __func__, smp_processor_id(), cmcv.cmcv_vector);
677 }
678 
679 /*
680  * ia64_mca_cmc_vector_enable
681  *
682  *  Unmask the corrected machine check vector register in the processor.
683  *  This function is invoked on a per-processor basis.
684  *
685  * Inputs
686  *      dummy(unused)
687  *
688  * Outputs
689  *	None
690  */
691 static void
692 ia64_mca_cmc_vector_enable (void *dummy)
693 {
694 	cmcv_reg_t	cmcv;
695 
696 	cmcv.cmcv_regval = ia64_getreg(_IA64_REG_CR_CMCV);
697 
698 	cmcv.cmcv_mask = 0; /* Unmask/enable interrupt */
699 	ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
700 
701 	IA64_MCA_DEBUG("%s: CPU %d corrected machine check vector %#x enabled.\n",
702 		       __func__, smp_processor_id(), cmcv.cmcv_vector);
703 }
704 
705 /*
706  * ia64_mca_cmc_vector_disable_keventd
707  *
708  * Called via keventd (smp_call_function() is not safe in interrupt context) to
709  * disable the cmc interrupt vector.
710  */
711 static void
712 ia64_mca_cmc_vector_disable_keventd(struct work_struct *unused)
713 {
714 	on_each_cpu(ia64_mca_cmc_vector_disable, NULL, 0);
715 }
716 
717 /*
718  * ia64_mca_cmc_vector_enable_keventd
719  *
720  * Called via keventd (smp_call_function() is not safe in interrupt context) to
721  * enable the cmc interrupt vector.
722  */
723 static void
724 ia64_mca_cmc_vector_enable_keventd(struct work_struct *unused)
725 {
726 	on_each_cpu(ia64_mca_cmc_vector_enable, NULL, 0);
727 }
728 
729 /*
730  * ia64_mca_wakeup
731  *
732  *	Send an inter-cpu interrupt to wake-up a particular cpu.
733  *
734  *  Inputs  :   cpuid
735  *  Outputs :   None
736  */
737 static void
738 ia64_mca_wakeup(int cpu)
739 {
740 	ia64_send_ipi(cpu, IA64_MCA_WAKEUP_VECTOR, IA64_IPI_DM_INT, 0);
741 }
742 
743 /*
744  * ia64_mca_wakeup_all
745  *
746  *	Wakeup all the slave cpus which have rendez'ed previously.
747  *
748  *  Inputs  :   None
749  *  Outputs :   None
750  */
751 static void
752 ia64_mca_wakeup_all(void)
753 {
754 	int cpu;
755 
756 	/* Clear the Rendez checkin flag for all cpus */
757 	for_each_online_cpu(cpu) {
758 		if (ia64_mc_info.imi_rendez_checkin[cpu] == IA64_MCA_RENDEZ_CHECKIN_DONE)
759 			ia64_mca_wakeup(cpu);
760 	}
761 
762 }
763 
764 /*
765  * ia64_mca_rendez_interrupt_handler
766  *
767  *	This is handler used to put slave processors into spinloop
768  *	while the monarch processor does the mca handling and later
769  *	wake each slave up once the monarch is done.  The state
770  *	IA64_MCA_RENDEZ_CHECKIN_DONE indicates the cpu is rendez'ed
771  *	in SAL.  The state IA64_MCA_RENDEZ_CHECKIN_NOTDONE indicates
772  *	the cpu has come out of OS rendezvous.
773  *
774  *  Inputs  :   None
775  *  Outputs :   None
776  */
777 static irqreturn_t
778 ia64_mca_rendez_int_handler(int rendez_irq, void *arg)
779 {
780 	unsigned long flags;
781 	int cpu = smp_processor_id();
782 	struct ia64_mca_notify_die nd =
783 		{ .sos = NULL, .monarch_cpu = &monarch_cpu };
784 
785 	/* Mask all interrupts */
786 	local_irq_save(flags);
787 
788 	NOTIFY_MCA(DIE_MCA_RENDZVOUS_ENTER, get_irq_regs(), (long)&nd, 1);
789 
790 	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_DONE;
791 	/* Register with the SAL monarch that the slave has
792 	 * reached SAL
793 	 */
794 	ia64_sal_mc_rendez();
795 
796 	NOTIFY_MCA(DIE_MCA_RENDZVOUS_PROCESS, get_irq_regs(), (long)&nd, 1);
797 
798 	/* Wait for the monarch cpu to exit. */
799 	while (monarch_cpu != -1)
800 	       cpu_relax();	/* spin until monarch leaves */
801 
802 	NOTIFY_MCA(DIE_MCA_RENDZVOUS_LEAVE, get_irq_regs(), (long)&nd, 1);
803 
804 	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
805 	/* Enable all interrupts */
806 	local_irq_restore(flags);
807 	return IRQ_HANDLED;
808 }
809 
810 /*
811  * ia64_mca_wakeup_int_handler
812  *
813  *	The interrupt handler for processing the inter-cpu interrupt to the
814  *	slave cpu which was spinning in the rendez loop.
815  *	Since this spinning is done by turning off the interrupts and
816  *	polling on the wakeup-interrupt bit in the IRR, there is
817  *	nothing useful to be done in the handler.
818  *
819  *  Inputs  :   wakeup_irq  (Wakeup-interrupt bit)
820  *	arg		(Interrupt handler specific argument)
821  *  Outputs :   None
822  *
823  */
824 static irqreturn_t
825 ia64_mca_wakeup_int_handler(int wakeup_irq, void *arg)
826 {
827 	return IRQ_HANDLED;
828 }
829 
830 /* Function pointer for extra MCA recovery */
831 int (*ia64_mca_ucmc_extension)
832 	(void*,struct ia64_sal_os_state*)
833 	= NULL;
834 
835 int
836 ia64_reg_MCA_extension(int (*fn)(void *, struct ia64_sal_os_state *))
837 {
838 	if (ia64_mca_ucmc_extension)
839 		return 1;
840 
841 	ia64_mca_ucmc_extension = fn;
842 	return 0;
843 }
844 
845 void
846 ia64_unreg_MCA_extension(void)
847 {
848 	if (ia64_mca_ucmc_extension)
849 		ia64_mca_ucmc_extension = NULL;
850 }
851 
852 EXPORT_SYMBOL(ia64_reg_MCA_extension);
853 EXPORT_SYMBOL(ia64_unreg_MCA_extension);
854 
855 
856 static inline void
857 copy_reg(const u64 *fr, u64 fnat, unsigned long *tr, unsigned long *tnat)
858 {
859 	u64 fslot, tslot, nat;
860 	*tr = *fr;
861 	fslot = ((unsigned long)fr >> 3) & 63;
862 	tslot = ((unsigned long)tr >> 3) & 63;
863 	*tnat &= ~(1UL << tslot);
864 	nat = (fnat >> fslot) & 1;
865 	*tnat |= (nat << tslot);
866 }
867 
868 /* Change the comm field on the MCA/INT task to include the pid that
869  * was interrupted, it makes for easier debugging.  If that pid was 0
870  * (swapper or nested MCA/INIT) then use the start of the previous comm
871  * field suffixed with its cpu.
872  */
873 
874 static void
875 ia64_mca_modify_comm(const struct task_struct *previous_current)
876 {
877 	char *p, comm[sizeof(current->comm)];
878 	if (previous_current->pid)
879 		snprintf(comm, sizeof(comm), "%s %d",
880 			current->comm, previous_current->pid);
881 	else {
882 		int l;
883 		if ((p = strchr(previous_current->comm, ' ')))
884 			l = p - previous_current->comm;
885 		else
886 			l = strlen(previous_current->comm);
887 		snprintf(comm, sizeof(comm), "%s %*s %d",
888 			current->comm, l, previous_current->comm,
889 			task_thread_info(previous_current)->cpu);
890 	}
891 	memcpy(current->comm, comm, sizeof(current->comm));
892 }
893 
894 static void
895 finish_pt_regs(struct pt_regs *regs, struct ia64_sal_os_state *sos,
896 		unsigned long *nat)
897 {
898 	const pal_min_state_area_t *ms = sos->pal_min_state;
899 	const u64 *bank;
900 
901 	/* If ipsr.ic then use pmsa_{iip,ipsr,ifs}, else use
902 	 * pmsa_{xip,xpsr,xfs}
903 	 */
904 	if (ia64_psr(regs)->ic) {
905 		regs->cr_iip = ms->pmsa_iip;
906 		regs->cr_ipsr = ms->pmsa_ipsr;
907 		regs->cr_ifs = ms->pmsa_ifs;
908 	} else {
909 		regs->cr_iip = ms->pmsa_xip;
910 		regs->cr_ipsr = ms->pmsa_xpsr;
911 		regs->cr_ifs = ms->pmsa_xfs;
912 
913 		sos->iip = ms->pmsa_iip;
914 		sos->ipsr = ms->pmsa_ipsr;
915 		sos->ifs = ms->pmsa_ifs;
916 	}
917 	regs->pr = ms->pmsa_pr;
918 	regs->b0 = ms->pmsa_br0;
919 	regs->ar_rsc = ms->pmsa_rsc;
920 	copy_reg(&ms->pmsa_gr[1-1], ms->pmsa_nat_bits, &regs->r1, nat);
921 	copy_reg(&ms->pmsa_gr[2-1], ms->pmsa_nat_bits, &regs->r2, nat);
922 	copy_reg(&ms->pmsa_gr[3-1], ms->pmsa_nat_bits, &regs->r3, nat);
923 	copy_reg(&ms->pmsa_gr[8-1], ms->pmsa_nat_bits, &regs->r8, nat);
924 	copy_reg(&ms->pmsa_gr[9-1], ms->pmsa_nat_bits, &regs->r9, nat);
925 	copy_reg(&ms->pmsa_gr[10-1], ms->pmsa_nat_bits, &regs->r10, nat);
926 	copy_reg(&ms->pmsa_gr[11-1], ms->pmsa_nat_bits, &regs->r11, nat);
927 	copy_reg(&ms->pmsa_gr[12-1], ms->pmsa_nat_bits, &regs->r12, nat);
928 	copy_reg(&ms->pmsa_gr[13-1], ms->pmsa_nat_bits, &regs->r13, nat);
929 	copy_reg(&ms->pmsa_gr[14-1], ms->pmsa_nat_bits, &regs->r14, nat);
930 	copy_reg(&ms->pmsa_gr[15-1], ms->pmsa_nat_bits, &regs->r15, nat);
931 	if (ia64_psr(regs)->bn)
932 		bank = ms->pmsa_bank1_gr;
933 	else
934 		bank = ms->pmsa_bank0_gr;
935 	copy_reg(&bank[16-16], ms->pmsa_nat_bits, &regs->r16, nat);
936 	copy_reg(&bank[17-16], ms->pmsa_nat_bits, &regs->r17, nat);
937 	copy_reg(&bank[18-16], ms->pmsa_nat_bits, &regs->r18, nat);
938 	copy_reg(&bank[19-16], ms->pmsa_nat_bits, &regs->r19, nat);
939 	copy_reg(&bank[20-16], ms->pmsa_nat_bits, &regs->r20, nat);
940 	copy_reg(&bank[21-16], ms->pmsa_nat_bits, &regs->r21, nat);
941 	copy_reg(&bank[22-16], ms->pmsa_nat_bits, &regs->r22, nat);
942 	copy_reg(&bank[23-16], ms->pmsa_nat_bits, &regs->r23, nat);
943 	copy_reg(&bank[24-16], ms->pmsa_nat_bits, &regs->r24, nat);
944 	copy_reg(&bank[25-16], ms->pmsa_nat_bits, &regs->r25, nat);
945 	copy_reg(&bank[26-16], ms->pmsa_nat_bits, &regs->r26, nat);
946 	copy_reg(&bank[27-16], ms->pmsa_nat_bits, &regs->r27, nat);
947 	copy_reg(&bank[28-16], ms->pmsa_nat_bits, &regs->r28, nat);
948 	copy_reg(&bank[29-16], ms->pmsa_nat_bits, &regs->r29, nat);
949 	copy_reg(&bank[30-16], ms->pmsa_nat_bits, &regs->r30, nat);
950 	copy_reg(&bank[31-16], ms->pmsa_nat_bits, &regs->r31, nat);
951 }
952 
953 /* On entry to this routine, we are running on the per cpu stack, see
954  * mca_asm.h.  The original stack has not been touched by this event.  Some of
955  * the original stack's registers will be in the RBS on this stack.  This stack
956  * also contains a partial pt_regs and switch_stack, the rest of the data is in
957  * PAL minstate.
958  *
959  * The first thing to do is modify the original stack to look like a blocked
960  * task so we can run backtrace on the original task.  Also mark the per cpu
961  * stack as current to ensure that we use the correct task state, it also means
962  * that we can do backtrace on the MCA/INIT handler code itself.
963  */
964 
965 static struct task_struct *
966 ia64_mca_modify_original_stack(struct pt_regs *regs,
967 		const struct switch_stack *sw,
968 		struct ia64_sal_os_state *sos,
969 		const char *type)
970 {
971 	char *p;
972 	ia64_va va;
973 	extern char ia64_leave_kernel[];	/* Need asm address, not function descriptor */
974 	const pal_min_state_area_t *ms = sos->pal_min_state;
975 	struct task_struct *previous_current;
976 	struct pt_regs *old_regs;
977 	struct switch_stack *old_sw;
978 	unsigned size = sizeof(struct pt_regs) +
979 			sizeof(struct switch_stack) + 16;
980 	unsigned long *old_bspstore, *old_bsp;
981 	unsigned long *new_bspstore, *new_bsp;
982 	unsigned long old_unat, old_rnat, new_rnat, nat;
983 	u64 slots, loadrs = regs->loadrs;
984 	u64 r12 = ms->pmsa_gr[12-1], r13 = ms->pmsa_gr[13-1];
985 	u64 ar_bspstore = regs->ar_bspstore;
986 	u64 ar_bsp = regs->ar_bspstore + (loadrs >> 16);
987 	const char *msg;
988 	int cpu = smp_processor_id();
989 
990 	previous_current = curr_task(cpu);
991 	ia64_set_curr_task(cpu, current);
992 	if ((p = strchr(current->comm, ' ')))
993 		*p = '\0';
994 
995 	/* Best effort attempt to cope with MCA/INIT delivered while in
996 	 * physical mode.
997 	 */
998 	regs->cr_ipsr = ms->pmsa_ipsr;
999 	if (ia64_psr(regs)->dt == 0) {
1000 		va.l = r12;
1001 		if (va.f.reg == 0) {
1002 			va.f.reg = 7;
1003 			r12 = va.l;
1004 		}
1005 		va.l = r13;
1006 		if (va.f.reg == 0) {
1007 			va.f.reg = 7;
1008 			r13 = va.l;
1009 		}
1010 	}
1011 	if (ia64_psr(regs)->rt == 0) {
1012 		va.l = ar_bspstore;
1013 		if (va.f.reg == 0) {
1014 			va.f.reg = 7;
1015 			ar_bspstore = va.l;
1016 		}
1017 		va.l = ar_bsp;
1018 		if (va.f.reg == 0) {
1019 			va.f.reg = 7;
1020 			ar_bsp = va.l;
1021 		}
1022 	}
1023 
1024 	/* mca_asm.S ia64_old_stack() cannot assume that the dirty registers
1025 	 * have been copied to the old stack, the old stack may fail the
1026 	 * validation tests below.  So ia64_old_stack() must restore the dirty
1027 	 * registers from the new stack.  The old and new bspstore probably
1028 	 * have different alignments, so loadrs calculated on the old bsp
1029 	 * cannot be used to restore from the new bsp.  Calculate a suitable
1030 	 * loadrs for the new stack and save it in the new pt_regs, where
1031 	 * ia64_old_stack() can get it.
1032 	 */
1033 	old_bspstore = (unsigned long *)ar_bspstore;
1034 	old_bsp = (unsigned long *)ar_bsp;
1035 	slots = ia64_rse_num_regs(old_bspstore, old_bsp);
1036 	new_bspstore = (unsigned long *)((u64)current + IA64_RBS_OFFSET);
1037 	new_bsp = ia64_rse_skip_regs(new_bspstore, slots);
1038 	regs->loadrs = (new_bsp - new_bspstore) * 8 << 16;
1039 
1040 	/* Verify the previous stack state before we change it */
1041 	if (user_mode(regs)) {
1042 		msg = "occurred in user space";
1043 		/* previous_current is guaranteed to be valid when the task was
1044 		 * in user space, so ...
1045 		 */
1046 		ia64_mca_modify_comm(previous_current);
1047 		goto no_mod;
1048 	}
1049 
1050 	if (r13 != sos->prev_IA64_KR_CURRENT) {
1051 		msg = "inconsistent previous current and r13";
1052 		goto no_mod;
1053 	}
1054 
1055 	if (!mca_recover_range(ms->pmsa_iip)) {
1056 		if ((r12 - r13) >= KERNEL_STACK_SIZE) {
1057 			msg = "inconsistent r12 and r13";
1058 			goto no_mod;
1059 		}
1060 		if ((ar_bspstore - r13) >= KERNEL_STACK_SIZE) {
1061 			msg = "inconsistent ar.bspstore and r13";
1062 			goto no_mod;
1063 		}
1064 		va.p = old_bspstore;
1065 		if (va.f.reg < 5) {
1066 			msg = "old_bspstore is in the wrong region";
1067 			goto no_mod;
1068 		}
1069 		if ((ar_bsp - r13) >= KERNEL_STACK_SIZE) {
1070 			msg = "inconsistent ar.bsp and r13";
1071 			goto no_mod;
1072 		}
1073 		size += (ia64_rse_skip_regs(old_bspstore, slots) - old_bspstore) * 8;
1074 		if (ar_bspstore + size > r12) {
1075 			msg = "no room for blocked state";
1076 			goto no_mod;
1077 		}
1078 	}
1079 
1080 	ia64_mca_modify_comm(previous_current);
1081 
1082 	/* Make the original task look blocked.  First stack a struct pt_regs,
1083 	 * describing the state at the time of interrupt.  mca_asm.S built a
1084 	 * partial pt_regs, copy it and fill in the blanks using minstate.
1085 	 */
1086 	p = (char *)r12 - sizeof(*regs);
1087 	old_regs = (struct pt_regs *)p;
1088 	memcpy(old_regs, regs, sizeof(*regs));
1089 	old_regs->loadrs = loadrs;
1090 	old_unat = old_regs->ar_unat;
1091 	finish_pt_regs(old_regs, sos, &old_unat);
1092 
1093 	/* Next stack a struct switch_stack.  mca_asm.S built a partial
1094 	 * switch_stack, copy it and fill in the blanks using pt_regs and
1095 	 * minstate.
1096 	 *
1097 	 * In the synthesized switch_stack, b0 points to ia64_leave_kernel,
1098 	 * ar.pfs is set to 0.
1099 	 *
1100 	 * unwind.c::unw_unwind() does special processing for interrupt frames.
1101 	 * It checks if the PRED_NON_SYSCALL predicate is set, if the predicate
1102 	 * is clear then unw_unwind() does _not_ adjust bsp over pt_regs.  Not
1103 	 * that this is documented, of course.  Set PRED_NON_SYSCALL in the
1104 	 * switch_stack on the original stack so it will unwind correctly when
1105 	 * unwind.c reads pt_regs.
1106 	 *
1107 	 * thread.ksp is updated to point to the synthesized switch_stack.
1108 	 */
1109 	p -= sizeof(struct switch_stack);
1110 	old_sw = (struct switch_stack *)p;
1111 	memcpy(old_sw, sw, sizeof(*sw));
1112 	old_sw->caller_unat = old_unat;
1113 	old_sw->ar_fpsr = old_regs->ar_fpsr;
1114 	copy_reg(&ms->pmsa_gr[4-1], ms->pmsa_nat_bits, &old_sw->r4, &old_unat);
1115 	copy_reg(&ms->pmsa_gr[5-1], ms->pmsa_nat_bits, &old_sw->r5, &old_unat);
1116 	copy_reg(&ms->pmsa_gr[6-1], ms->pmsa_nat_bits, &old_sw->r6, &old_unat);
1117 	copy_reg(&ms->pmsa_gr[7-1], ms->pmsa_nat_bits, &old_sw->r7, &old_unat);
1118 	old_sw->b0 = (u64)ia64_leave_kernel;
1119 	old_sw->b1 = ms->pmsa_br1;
1120 	old_sw->ar_pfs = 0;
1121 	old_sw->ar_unat = old_unat;
1122 	old_sw->pr = old_regs->pr | (1UL << PRED_NON_SYSCALL);
1123 	previous_current->thread.ksp = (u64)p - 16;
1124 
1125 	/* Finally copy the original stack's registers back to its RBS.
1126 	 * Registers from ar.bspstore through ar.bsp at the time of the event
1127 	 * are in the current RBS, copy them back to the original stack.  The
1128 	 * copy must be done register by register because the original bspstore
1129 	 * and the current one have different alignments, so the saved RNAT
1130 	 * data occurs at different places.
1131 	 *
1132 	 * mca_asm does cover, so the old_bsp already includes all registers at
1133 	 * the time of MCA/INIT.  It also does flushrs, so all registers before
1134 	 * this function have been written to backing store on the MCA/INIT
1135 	 * stack.
1136 	 */
1137 	new_rnat = ia64_get_rnat(ia64_rse_rnat_addr(new_bspstore));
1138 	old_rnat = regs->ar_rnat;
1139 	while (slots--) {
1140 		if (ia64_rse_is_rnat_slot(new_bspstore)) {
1141 			new_rnat = ia64_get_rnat(new_bspstore++);
1142 		}
1143 		if (ia64_rse_is_rnat_slot(old_bspstore)) {
1144 			*old_bspstore++ = old_rnat;
1145 			old_rnat = 0;
1146 		}
1147 		nat = (new_rnat >> ia64_rse_slot_num(new_bspstore)) & 1UL;
1148 		old_rnat &= ~(1UL << ia64_rse_slot_num(old_bspstore));
1149 		old_rnat |= (nat << ia64_rse_slot_num(old_bspstore));
1150 		*old_bspstore++ = *new_bspstore++;
1151 	}
1152 	old_sw->ar_bspstore = (unsigned long)old_bspstore;
1153 	old_sw->ar_rnat = old_rnat;
1154 
1155 	sos->prev_task = previous_current;
1156 	return previous_current;
1157 
1158 no_mod:
1159 	mprintk(KERN_INFO "cpu %d, %s %s, original stack not modified\n",
1160 			smp_processor_id(), type, msg);
1161 	old_unat = regs->ar_unat;
1162 	finish_pt_regs(regs, sos, &old_unat);
1163 	return previous_current;
1164 }
1165 
1166 /* The monarch/slave interaction is based on monarch_cpu and requires that all
1167  * slaves have entered rendezvous before the monarch leaves.  If any cpu has
1168  * not entered rendezvous yet then wait a bit.  The assumption is that any
1169  * slave that has not rendezvoused after a reasonable time is never going to do
1170  * so.  In this context, slave includes cpus that respond to the MCA rendezvous
1171  * interrupt, as well as cpus that receive the INIT slave event.
1172  */
1173 
1174 static void
1175 ia64_wait_for_slaves(int monarch, const char *type)
1176 {
1177 	int c, i , wait;
1178 
1179 	/*
1180 	 * wait 5 seconds total for slaves (arbitrary)
1181 	 */
1182 	for (i = 0; i < 5000; i++) {
1183 		wait = 0;
1184 		for_each_online_cpu(c) {
1185 			if (c == monarch)
1186 				continue;
1187 			if (ia64_mc_info.imi_rendez_checkin[c]
1188 					== IA64_MCA_RENDEZ_CHECKIN_NOTDONE) {
1189 				udelay(1000);		/* short wait */
1190 				wait = 1;
1191 				break;
1192 			}
1193 		}
1194 		if (!wait)
1195 			goto all_in;
1196 	}
1197 
1198 	/*
1199 	 * Maybe slave(s) dead. Print buffered messages immediately.
1200 	 */
1201 	ia64_mlogbuf_finish(0);
1202 	mprintk(KERN_INFO "OS %s slave did not rendezvous on cpu", type);
1203 	for_each_online_cpu(c) {
1204 		if (c == monarch)
1205 			continue;
1206 		if (ia64_mc_info.imi_rendez_checkin[c] == IA64_MCA_RENDEZ_CHECKIN_NOTDONE)
1207 			mprintk(" %d", c);
1208 	}
1209 	mprintk("\n");
1210 	return;
1211 
1212 all_in:
1213 	mprintk(KERN_INFO "All OS %s slaves have reached rendezvous\n", type);
1214 	return;
1215 }
1216 
1217 /*  mca_insert_tr
1218  *
1219  *  Switch rid when TR reload and needed!
1220  *  iord: 1: itr, 2: itr;
1221  *
1222 */
1223 static void mca_insert_tr(u64 iord)
1224 {
1225 
1226 	int i;
1227 	u64 old_rr;
1228 	struct ia64_tr_entry *p;
1229 	unsigned long psr;
1230 	int cpu = smp_processor_id();
1231 
1232 	if (!ia64_idtrs[cpu])
1233 		return;
1234 
1235 	psr = ia64_clear_ic();
1236 	for (i = IA64_TR_ALLOC_BASE; i < IA64_TR_ALLOC_MAX; i++) {
1237 		p = ia64_idtrs[cpu] + (iord - 1) * IA64_TR_ALLOC_MAX;
1238 		if (p->pte & 0x1) {
1239 			old_rr = ia64_get_rr(p->ifa);
1240 			if (old_rr != p->rr) {
1241 				ia64_set_rr(p->ifa, p->rr);
1242 				ia64_srlz_d();
1243 			}
1244 			ia64_ptr(iord, p->ifa, p->itir >> 2);
1245 			ia64_srlz_i();
1246 			if (iord & 0x1) {
1247 				ia64_itr(0x1, i, p->ifa, p->pte, p->itir >> 2);
1248 				ia64_srlz_i();
1249 			}
1250 			if (iord & 0x2) {
1251 				ia64_itr(0x2, i, p->ifa, p->pte, p->itir >> 2);
1252 				ia64_srlz_i();
1253 			}
1254 			if (old_rr != p->rr) {
1255 				ia64_set_rr(p->ifa, old_rr);
1256 				ia64_srlz_d();
1257 			}
1258 		}
1259 	}
1260 	ia64_set_psr(psr);
1261 }
1262 
1263 /*
1264  * ia64_mca_handler
1265  *
1266  *	This is uncorrectable machine check handler called from OS_MCA
1267  *	dispatch code which is in turn called from SAL_CHECK().
1268  *	This is the place where the core of OS MCA handling is done.
1269  *	Right now the logs are extracted and displayed in a well-defined
1270  *	format. This handler code is supposed to be run only on the
1271  *	monarch processor. Once the monarch is done with MCA handling
1272  *	further MCA logging is enabled by clearing logs.
1273  *	Monarch also has the duty of sending wakeup-IPIs to pull the
1274  *	slave processors out of rendezvous spinloop.
1275  *
1276  *	If multiple processors call into OS_MCA, the first will become
1277  *	the monarch.  Subsequent cpus will be recorded in the mca_cpu
1278  *	bitmask.  After the first monarch has processed its MCA, it
1279  *	will wake up the next cpu in the mca_cpu bitmask and then go
1280  *	into the rendezvous loop.  When all processors have serviced
1281  *	their MCA, the last monarch frees up the rest of the processors.
1282  */
1283 void
1284 ia64_mca_handler(struct pt_regs *regs, struct switch_stack *sw,
1285 		 struct ia64_sal_os_state *sos)
1286 {
1287 	int recover, cpu = smp_processor_id();
1288 	struct task_struct *previous_current;
1289 	struct ia64_mca_notify_die nd =
1290 		{ .sos = sos, .monarch_cpu = &monarch_cpu, .data = &recover };
1291 	static atomic_t mca_count;
1292 	static cpumask_t mca_cpu;
1293 
1294 	if (atomic_add_return(1, &mca_count) == 1) {
1295 		monarch_cpu = cpu;
1296 		sos->monarch = 1;
1297 	} else {
1298 		cpumask_set_cpu(cpu, &mca_cpu);
1299 		sos->monarch = 0;
1300 	}
1301 	mprintk(KERN_INFO "Entered OS MCA handler. PSP=%lx cpu=%d "
1302 		"monarch=%ld\n", sos->proc_state_param, cpu, sos->monarch);
1303 
1304 	previous_current = ia64_mca_modify_original_stack(regs, sw, sos, "MCA");
1305 
1306 	NOTIFY_MCA(DIE_MCA_MONARCH_ENTER, regs, (long)&nd, 1);
1307 
1308 	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_CONCURRENT_MCA;
1309 	if (sos->monarch) {
1310 		ia64_wait_for_slaves(cpu, "MCA");
1311 
1312 		/* Wakeup all the processors which are spinning in the
1313 		 * rendezvous loop.  They will leave SAL, then spin in the OS
1314 		 * with interrupts disabled until this monarch cpu leaves the
1315 		 * MCA handler.  That gets control back to the OS so we can
1316 		 * backtrace the other cpus, backtrace when spinning in SAL
1317 		 * does not work.
1318 		 */
1319 		ia64_mca_wakeup_all();
1320 	} else {
1321 		while (cpumask_test_cpu(cpu, &mca_cpu))
1322 			cpu_relax();	/* spin until monarch wakes us */
1323 	}
1324 
1325 	NOTIFY_MCA(DIE_MCA_MONARCH_PROCESS, regs, (long)&nd, 1);
1326 
1327 	/* Get the MCA error record and log it */
1328 	ia64_mca_log_sal_error_record(SAL_INFO_TYPE_MCA);
1329 
1330 	/* MCA error recovery */
1331 	recover = (ia64_mca_ucmc_extension
1332 		&& ia64_mca_ucmc_extension(
1333 			IA64_LOG_CURR_BUFFER(SAL_INFO_TYPE_MCA),
1334 			sos));
1335 
1336 	if (recover) {
1337 		sal_log_record_header_t *rh = IA64_LOG_CURR_BUFFER(SAL_INFO_TYPE_MCA);
1338 		rh->severity = sal_log_severity_corrected;
1339 		ia64_sal_clear_state_info(SAL_INFO_TYPE_MCA);
1340 		sos->os_status = IA64_MCA_CORRECTED;
1341 	} else {
1342 		/* Dump buffered message to console */
1343 		ia64_mlogbuf_finish(1);
1344 	}
1345 
1346 	if (__this_cpu_read(ia64_mca_tr_reload)) {
1347 		mca_insert_tr(0x1); /*Reload dynamic itrs*/
1348 		mca_insert_tr(0x2); /*Reload dynamic itrs*/
1349 	}
1350 
1351 	NOTIFY_MCA(DIE_MCA_MONARCH_LEAVE, regs, (long)&nd, 1);
1352 
1353 	if (atomic_dec_return(&mca_count) > 0) {
1354 		int i;
1355 
1356 		/* wake up the next monarch cpu,
1357 		 * and put this cpu in the rendez loop.
1358 		 */
1359 		for_each_online_cpu(i) {
1360 			if (cpumask_test_cpu(i, &mca_cpu)) {
1361 				monarch_cpu = i;
1362 				cpumask_clear_cpu(i, &mca_cpu);	/* wake next cpu */
1363 				while (monarch_cpu != -1)
1364 					cpu_relax();	/* spin until last cpu leaves */
1365 				ia64_set_curr_task(cpu, previous_current);
1366 				ia64_mc_info.imi_rendez_checkin[cpu]
1367 						= IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
1368 				return;
1369 			}
1370 		}
1371 	}
1372 	ia64_set_curr_task(cpu, previous_current);
1373 	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
1374 	monarch_cpu = -1;	/* This frees the slaves and previous monarchs */
1375 }
1376 
1377 static DECLARE_WORK(cmc_disable_work, ia64_mca_cmc_vector_disable_keventd);
1378 static DECLARE_WORK(cmc_enable_work, ia64_mca_cmc_vector_enable_keventd);
1379 
1380 /*
1381  * ia64_mca_cmc_int_handler
1382  *
1383  *  This is corrected machine check interrupt handler.
1384  *	Right now the logs are extracted and displayed in a well-defined
1385  *	format.
1386  *
1387  * Inputs
1388  *      interrupt number
1389  *      client data arg ptr
1390  *
1391  * Outputs
1392  *	None
1393  */
1394 static irqreturn_t
1395 ia64_mca_cmc_int_handler(int cmc_irq, void *arg)
1396 {
1397 	static unsigned long	cmc_history[CMC_HISTORY_LENGTH];
1398 	static int		index;
1399 	static DEFINE_SPINLOCK(cmc_history_lock);
1400 
1401 	IA64_MCA_DEBUG("%s: received interrupt vector = %#x on CPU %d\n",
1402 		       __func__, cmc_irq, smp_processor_id());
1403 
1404 	/* SAL spec states this should run w/ interrupts enabled */
1405 	local_irq_enable();
1406 
1407 	spin_lock(&cmc_history_lock);
1408 	if (!cmc_polling_enabled) {
1409 		int i, count = 1; /* we know 1 happened now */
1410 		unsigned long now = jiffies;
1411 
1412 		for (i = 0; i < CMC_HISTORY_LENGTH; i++) {
1413 			if (now - cmc_history[i] <= HZ)
1414 				count++;
1415 		}
1416 
1417 		IA64_MCA_DEBUG(KERN_INFO "CMC threshold %d/%d\n", count, CMC_HISTORY_LENGTH);
1418 		if (count >= CMC_HISTORY_LENGTH) {
1419 
1420 			cmc_polling_enabled = 1;
1421 			spin_unlock(&cmc_history_lock);
1422 			/* If we're being hit with CMC interrupts, we won't
1423 			 * ever execute the schedule_work() below.  Need to
1424 			 * disable CMC interrupts on this processor now.
1425 			 */
1426 			ia64_mca_cmc_vector_disable(NULL);
1427 			schedule_work(&cmc_disable_work);
1428 
1429 			/*
1430 			 * Corrected errors will still be corrected, but
1431 			 * make sure there's a log somewhere that indicates
1432 			 * something is generating more than we can handle.
1433 			 */
1434 			printk(KERN_WARNING "WARNING: Switching to polling CMC handler; error records may be lost\n");
1435 
1436 			mod_timer(&cmc_poll_timer, jiffies + CMC_POLL_INTERVAL);
1437 
1438 			/* lock already released, get out now */
1439 			goto out;
1440 		} else {
1441 			cmc_history[index++] = now;
1442 			if (index == CMC_HISTORY_LENGTH)
1443 				index = 0;
1444 		}
1445 	}
1446 	spin_unlock(&cmc_history_lock);
1447 out:
1448 	/* Get the CMC error record and log it */
1449 	ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CMC);
1450 
1451 	local_irq_disable();
1452 
1453 	return IRQ_HANDLED;
1454 }
1455 
1456 /*
1457  *  ia64_mca_cmc_int_caller
1458  *
1459  * 	Triggered by sw interrupt from CMC polling routine.  Calls
1460  * 	real interrupt handler and either triggers a sw interrupt
1461  * 	on the next cpu or does cleanup at the end.
1462  *
1463  * Inputs
1464  *	interrupt number
1465  *	client data arg ptr
1466  * Outputs
1467  * 	handled
1468  */
1469 static irqreturn_t
1470 ia64_mca_cmc_int_caller(int cmc_irq, void *arg)
1471 {
1472 	static int start_count = -1;
1473 	unsigned int cpuid;
1474 
1475 	cpuid = smp_processor_id();
1476 
1477 	/* If first cpu, update count */
1478 	if (start_count == -1)
1479 		start_count = IA64_LOG_COUNT(SAL_INFO_TYPE_CMC);
1480 
1481 	ia64_mca_cmc_int_handler(cmc_irq, arg);
1482 
1483 	cpuid = cpumask_next(cpuid+1, cpu_online_mask);
1484 
1485 	if (cpuid < nr_cpu_ids) {
1486 		ia64_send_ipi(cpuid, IA64_CMCP_VECTOR, IA64_IPI_DM_INT, 0);
1487 	} else {
1488 		/* If no log record, switch out of polling mode */
1489 		if (start_count == IA64_LOG_COUNT(SAL_INFO_TYPE_CMC)) {
1490 
1491 			printk(KERN_WARNING "Returning to interrupt driven CMC handler\n");
1492 			schedule_work(&cmc_enable_work);
1493 			cmc_polling_enabled = 0;
1494 
1495 		} else {
1496 
1497 			mod_timer(&cmc_poll_timer, jiffies + CMC_POLL_INTERVAL);
1498 		}
1499 
1500 		start_count = -1;
1501 	}
1502 
1503 	return IRQ_HANDLED;
1504 }
1505 
1506 /*
1507  *  ia64_mca_cmc_poll
1508  *
1509  *	Poll for Corrected Machine Checks (CMCs)
1510  *
1511  * Inputs   :   dummy(unused)
1512  * Outputs  :   None
1513  *
1514  */
1515 static void
1516 ia64_mca_cmc_poll (struct timer_list *unused)
1517 {
1518 	/* Trigger a CMC interrupt cascade  */
1519 	ia64_send_ipi(cpumask_first(cpu_online_mask), IA64_CMCP_VECTOR,
1520 							IA64_IPI_DM_INT, 0);
1521 }
1522 
1523 /*
1524  *  ia64_mca_cpe_int_caller
1525  *
1526  * 	Triggered by sw interrupt from CPE polling routine.  Calls
1527  * 	real interrupt handler and either triggers a sw interrupt
1528  * 	on the next cpu or does cleanup at the end.
1529  *
1530  * Inputs
1531  *	interrupt number
1532  *	client data arg ptr
1533  * Outputs
1534  * 	handled
1535  */
1536 static irqreturn_t
1537 ia64_mca_cpe_int_caller(int cpe_irq, void *arg)
1538 {
1539 	static int start_count = -1;
1540 	static int poll_time = MIN_CPE_POLL_INTERVAL;
1541 	unsigned int cpuid;
1542 
1543 	cpuid = smp_processor_id();
1544 
1545 	/* If first cpu, update count */
1546 	if (start_count == -1)
1547 		start_count = IA64_LOG_COUNT(SAL_INFO_TYPE_CPE);
1548 
1549 	ia64_mca_cpe_int_handler(cpe_irq, arg);
1550 
1551 	cpuid = cpumask_next(cpuid+1, cpu_online_mask);
1552 
1553 	if (cpuid < NR_CPUS) {
1554 		ia64_send_ipi(cpuid, IA64_CPEP_VECTOR, IA64_IPI_DM_INT, 0);
1555 	} else {
1556 		/*
1557 		 * If a log was recorded, increase our polling frequency,
1558 		 * otherwise, backoff or return to interrupt mode.
1559 		 */
1560 		if (start_count != IA64_LOG_COUNT(SAL_INFO_TYPE_CPE)) {
1561 			poll_time = max(MIN_CPE_POLL_INTERVAL, poll_time / 2);
1562 		} else if (cpe_vector < 0) {
1563 			poll_time = min(MAX_CPE_POLL_INTERVAL, poll_time * 2);
1564 		} else {
1565 			poll_time = MIN_CPE_POLL_INTERVAL;
1566 
1567 			printk(KERN_WARNING "Returning to interrupt driven CPE handler\n");
1568 			enable_irq(local_vector_to_irq(IA64_CPE_VECTOR));
1569 			cpe_poll_enabled = 0;
1570 		}
1571 
1572 		if (cpe_poll_enabled)
1573 			mod_timer(&cpe_poll_timer, jiffies + poll_time);
1574 		start_count = -1;
1575 	}
1576 
1577 	return IRQ_HANDLED;
1578 }
1579 
1580 /*
1581  *  ia64_mca_cpe_poll
1582  *
1583  *	Poll for Corrected Platform Errors (CPEs), trigger interrupt
1584  *	on first cpu, from there it will trickle through all the cpus.
1585  *
1586  * Inputs   :   dummy(unused)
1587  * Outputs  :   None
1588  *
1589  */
1590 static void
1591 ia64_mca_cpe_poll (struct timer_list *unused)
1592 {
1593 	/* Trigger a CPE interrupt cascade  */
1594 	ia64_send_ipi(cpumask_first(cpu_online_mask), IA64_CPEP_VECTOR,
1595 							IA64_IPI_DM_INT, 0);
1596 }
1597 
1598 static int
1599 default_monarch_init_process(struct notifier_block *self, unsigned long val, void *data)
1600 {
1601 	int c;
1602 	struct task_struct *g, *t;
1603 	if (val != DIE_INIT_MONARCH_PROCESS)
1604 		return NOTIFY_DONE;
1605 #ifdef CONFIG_KEXEC
1606 	if (atomic_read(&kdump_in_progress))
1607 		return NOTIFY_DONE;
1608 #endif
1609 
1610 	/*
1611 	 * FIXME: mlogbuf will brim over with INIT stack dumps.
1612 	 * To enable show_stack from INIT, we use oops_in_progress which should
1613 	 * be used in real oops. This would cause something wrong after INIT.
1614 	 */
1615 	BREAK_LOGLEVEL(console_loglevel);
1616 	ia64_mlogbuf_dump_from_init();
1617 
1618 	printk(KERN_ERR "Processes interrupted by INIT -");
1619 	for_each_online_cpu(c) {
1620 		struct ia64_sal_os_state *s;
1621 		t = __va(__per_cpu_mca[c] + IA64_MCA_CPU_INIT_STACK_OFFSET);
1622 		s = (struct ia64_sal_os_state *)((char *)t + MCA_SOS_OFFSET);
1623 		g = s->prev_task;
1624 		if (g) {
1625 			if (g->pid)
1626 				printk(" %d", g->pid);
1627 			else
1628 				printk(" %d (cpu %d task 0x%p)", g->pid, task_cpu(g), g);
1629 		}
1630 	}
1631 	printk("\n\n");
1632 	if (read_trylock(&tasklist_lock)) {
1633 		do_each_thread (g, t) {
1634 			printk("\nBacktrace of pid %d (%s)\n", t->pid, t->comm);
1635 			show_stack(t, NULL, KERN_DEFAULT);
1636 		} while_each_thread (g, t);
1637 		read_unlock(&tasklist_lock);
1638 	}
1639 	/* FIXME: This will not restore zapped printk locks. */
1640 	RESTORE_LOGLEVEL(console_loglevel);
1641 	return NOTIFY_DONE;
1642 }
1643 
1644 /*
1645  * C portion of the OS INIT handler
1646  *
1647  * Called from ia64_os_init_dispatch
1648  *
1649  * Inputs: pointer to pt_regs where processor info was saved.  SAL/OS state for
1650  * this event.  This code is used for both monarch and slave INIT events, see
1651  * sos->monarch.
1652  *
1653  * All INIT events switch to the INIT stack and change the previous process to
1654  * blocked status.  If one of the INIT events is the monarch then we are
1655  * probably processing the nmi button/command.  Use the monarch cpu to dump all
1656  * the processes.  The slave INIT events all spin until the monarch cpu
1657  * returns.  We can also get INIT slave events for MCA, in which case the MCA
1658  * process is the monarch.
1659  */
1660 
1661 void
1662 ia64_init_handler(struct pt_regs *regs, struct switch_stack *sw,
1663 		  struct ia64_sal_os_state *sos)
1664 {
1665 	static atomic_t slaves;
1666 	static atomic_t monarchs;
1667 	struct task_struct *previous_current;
1668 	int cpu = smp_processor_id();
1669 	struct ia64_mca_notify_die nd =
1670 		{ .sos = sos, .monarch_cpu = &monarch_cpu };
1671 
1672 	NOTIFY_INIT(DIE_INIT_ENTER, regs, (long)&nd, 0);
1673 
1674 	mprintk(KERN_INFO "Entered OS INIT handler. PSP=%lx cpu=%d monarch=%ld\n",
1675 		sos->proc_state_param, cpu, sos->monarch);
1676 	salinfo_log_wakeup(SAL_INFO_TYPE_INIT, NULL, 0, 0);
1677 
1678 	previous_current = ia64_mca_modify_original_stack(regs, sw, sos, "INIT");
1679 	sos->os_status = IA64_INIT_RESUME;
1680 
1681 	/* FIXME: Workaround for broken proms that drive all INIT events as
1682 	 * slaves.  The last slave that enters is promoted to be a monarch.
1683 	 * Remove this code in September 2006, that gives platforms a year to
1684 	 * fix their proms and get their customers updated.
1685 	 */
1686 	if (!sos->monarch && atomic_add_return(1, &slaves) == num_online_cpus()) {
1687 		mprintk(KERN_WARNING "%s: Promoting cpu %d to monarch.\n",
1688 		        __func__, cpu);
1689 		atomic_dec(&slaves);
1690 		sos->monarch = 1;
1691 	}
1692 
1693 	/* FIXME: Workaround for broken proms that drive all INIT events as
1694 	 * monarchs.  Second and subsequent monarchs are demoted to slaves.
1695 	 * Remove this code in September 2006, that gives platforms a year to
1696 	 * fix their proms and get their customers updated.
1697 	 */
1698 	if (sos->monarch && atomic_add_return(1, &monarchs) > 1) {
1699 		mprintk(KERN_WARNING "%s: Demoting cpu %d to slave.\n",
1700 			       __func__, cpu);
1701 		atomic_dec(&monarchs);
1702 		sos->monarch = 0;
1703 	}
1704 
1705 	if (!sos->monarch) {
1706 		ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_INIT;
1707 
1708 #ifdef CONFIG_KEXEC
1709 		while (monarch_cpu == -1 && !atomic_read(&kdump_in_progress))
1710 			udelay(1000);
1711 #else
1712 		while (monarch_cpu == -1)
1713 			cpu_relax();	/* spin until monarch enters */
1714 #endif
1715 
1716 		NOTIFY_INIT(DIE_INIT_SLAVE_ENTER, regs, (long)&nd, 1);
1717 		NOTIFY_INIT(DIE_INIT_SLAVE_PROCESS, regs, (long)&nd, 1);
1718 
1719 #ifdef CONFIG_KEXEC
1720 		while (monarch_cpu != -1 && !atomic_read(&kdump_in_progress))
1721 			udelay(1000);
1722 #else
1723 		while (monarch_cpu != -1)
1724 			cpu_relax();	/* spin until monarch leaves */
1725 #endif
1726 
1727 		NOTIFY_INIT(DIE_INIT_SLAVE_LEAVE, regs, (long)&nd, 1);
1728 
1729 		mprintk("Slave on cpu %d returning to normal service.\n", cpu);
1730 		ia64_set_curr_task(cpu, previous_current);
1731 		ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
1732 		atomic_dec(&slaves);
1733 		return;
1734 	}
1735 
1736 	monarch_cpu = cpu;
1737 	NOTIFY_INIT(DIE_INIT_MONARCH_ENTER, regs, (long)&nd, 1);
1738 
1739 	/*
1740 	 * Wait for a bit.  On some machines (e.g., HP's zx2000 and zx6000, INIT can be
1741 	 * generated via the BMC's command-line interface, but since the console is on the
1742 	 * same serial line, the user will need some time to switch out of the BMC before
1743 	 * the dump begins.
1744 	 */
1745 	mprintk("Delaying for 5 seconds...\n");
1746 	udelay(5*1000000);
1747 	ia64_wait_for_slaves(cpu, "INIT");
1748 	/* If nobody intercepts DIE_INIT_MONARCH_PROCESS then we drop through
1749 	 * to default_monarch_init_process() above and just print all the
1750 	 * tasks.
1751 	 */
1752 	NOTIFY_INIT(DIE_INIT_MONARCH_PROCESS, regs, (long)&nd, 1);
1753 	NOTIFY_INIT(DIE_INIT_MONARCH_LEAVE, regs, (long)&nd, 1);
1754 
1755 	mprintk("\nINIT dump complete.  Monarch on cpu %d returning to normal service.\n", cpu);
1756 	atomic_dec(&monarchs);
1757 	ia64_set_curr_task(cpu, previous_current);
1758 	monarch_cpu = -1;
1759 	return;
1760 }
1761 
1762 static int __init
1763 ia64_mca_disable_cpe_polling(char *str)
1764 {
1765 	cpe_poll_enabled = 0;
1766 	return 1;
1767 }
1768 
1769 __setup("disable_cpe_poll", ia64_mca_disable_cpe_polling);
1770 
1771 /* Minimal format of the MCA/INIT stacks.  The pseudo processes that run on
1772  * these stacks can never sleep, they cannot return from the kernel to user
1773  * space, they do not appear in a normal ps listing.  So there is no need to
1774  * format most of the fields.
1775  */
1776 
1777 static void
1778 format_mca_init_stack(void *mca_data, unsigned long offset,
1779 		const char *type, int cpu)
1780 {
1781 	struct task_struct *p = (struct task_struct *)((char *)mca_data + offset);
1782 	struct thread_info *ti;
1783 	memset(p, 0, KERNEL_STACK_SIZE);
1784 	ti = task_thread_info(p);
1785 	ti->flags = _TIF_MCA_INIT;
1786 	ti->preempt_count = 1;
1787 	ti->task = p;
1788 	ti->cpu = cpu;
1789 	p->stack = ti;
1790 	p->state = TASK_UNINTERRUPTIBLE;
1791 	cpumask_set_cpu(cpu, &p->cpus_mask);
1792 	INIT_LIST_HEAD(&p->tasks);
1793 	p->parent = p->real_parent = p->group_leader = p;
1794 	INIT_LIST_HEAD(&p->children);
1795 	INIT_LIST_HEAD(&p->sibling);
1796 	strncpy(p->comm, type, sizeof(p->comm)-1);
1797 }
1798 
1799 /* Caller prevents this from being called after init */
1800 static void * __ref mca_bootmem(void)
1801 {
1802 	return memblock_alloc(sizeof(struct ia64_mca_cpu), KERNEL_STACK_SIZE);
1803 }
1804 
1805 /* Do per-CPU MCA-related initialization.  */
1806 void
1807 ia64_mca_cpu_init(void *cpu_data)
1808 {
1809 	void *pal_vaddr;
1810 	void *data;
1811 	long sz = sizeof(struct ia64_mca_cpu);
1812 	int cpu = smp_processor_id();
1813 	static int first_time = 1;
1814 
1815 	/*
1816 	 * Structure will already be allocated if cpu has been online,
1817 	 * then offlined.
1818 	 */
1819 	if (__per_cpu_mca[cpu]) {
1820 		data = __va(__per_cpu_mca[cpu]);
1821 	} else {
1822 		if (first_time) {
1823 			data = mca_bootmem();
1824 			first_time = 0;
1825 		} else
1826 			data = (void *)__get_free_pages(GFP_KERNEL,
1827 							get_order(sz));
1828 		if (!data)
1829 			panic("Could not allocate MCA memory for cpu %d\n",
1830 					cpu);
1831 	}
1832 	format_mca_init_stack(data, offsetof(struct ia64_mca_cpu, mca_stack),
1833 		"MCA", cpu);
1834 	format_mca_init_stack(data, offsetof(struct ia64_mca_cpu, init_stack),
1835 		"INIT", cpu);
1836 	__this_cpu_write(ia64_mca_data, (__per_cpu_mca[cpu] = __pa(data)));
1837 
1838 	/*
1839 	 * Stash away a copy of the PTE needed to map the per-CPU page.
1840 	 * We may need it during MCA recovery.
1841 	 */
1842 	__this_cpu_write(ia64_mca_per_cpu_pte,
1843 		pte_val(mk_pte_phys(__pa(cpu_data), PAGE_KERNEL)));
1844 
1845 	/*
1846 	 * Also, stash away a copy of the PAL address and the PTE
1847 	 * needed to map it.
1848 	 */
1849 	pal_vaddr = efi_get_pal_addr();
1850 	if (!pal_vaddr)
1851 		return;
1852 	__this_cpu_write(ia64_mca_pal_base,
1853 		GRANULEROUNDDOWN((unsigned long) pal_vaddr));
1854 	__this_cpu_write(ia64_mca_pal_pte, pte_val(mk_pte_phys(__pa(pal_vaddr),
1855 							      PAGE_KERNEL)));
1856 }
1857 
1858 static int ia64_mca_cpu_online(unsigned int cpu)
1859 {
1860 	unsigned long flags;
1861 
1862 	local_irq_save(flags);
1863 	if (!cmc_polling_enabled)
1864 		ia64_mca_cmc_vector_enable(NULL);
1865 	local_irq_restore(flags);
1866 	return 0;
1867 }
1868 
1869 /*
1870  * ia64_mca_init
1871  *
1872  *  Do all the system level mca specific initialization.
1873  *
1874  *	1. Register spinloop and wakeup request interrupt vectors
1875  *
1876  *	2. Register OS_MCA handler entry point
1877  *
1878  *	3. Register OS_INIT handler entry point
1879  *
1880  *  4. Initialize MCA/CMC/INIT related log buffers maintained by the OS.
1881  *
1882  *  Note that this initialization is done very early before some kernel
1883  *  services are available.
1884  *
1885  *  Inputs  :   None
1886  *
1887  *  Outputs :   None
1888  */
1889 void __init
1890 ia64_mca_init(void)
1891 {
1892 	ia64_fptr_t *init_hldlr_ptr_monarch = (ia64_fptr_t *)ia64_os_init_dispatch_monarch;
1893 	ia64_fptr_t *init_hldlr_ptr_slave = (ia64_fptr_t *)ia64_os_init_dispatch_slave;
1894 	ia64_fptr_t *mca_hldlr_ptr = (ia64_fptr_t *)ia64_os_mca_dispatch;
1895 	int i;
1896 	long rc;
1897 	struct ia64_sal_retval isrv;
1898 	unsigned long timeout = IA64_MCA_RENDEZ_TIMEOUT; /* platform specific */
1899 	static struct notifier_block default_init_monarch_nb = {
1900 		.notifier_call = default_monarch_init_process,
1901 		.priority = 0/* we need to notified last */
1902 	};
1903 
1904 	IA64_MCA_DEBUG("%s: begin\n", __func__);
1905 
1906 	/* Clear the Rendez checkin flag for all cpus */
1907 	for(i = 0 ; i < NR_CPUS; i++)
1908 		ia64_mc_info.imi_rendez_checkin[i] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
1909 
1910 	/*
1911 	 * Register the rendezvous spinloop and wakeup mechanism with SAL
1912 	 */
1913 
1914 	/* Register the rendezvous interrupt vector with SAL */
1915 	while (1) {
1916 		isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_RENDEZ_INT,
1917 					      SAL_MC_PARAM_MECHANISM_INT,
1918 					      IA64_MCA_RENDEZ_VECTOR,
1919 					      timeout,
1920 					      SAL_MC_PARAM_RZ_ALWAYS);
1921 		rc = isrv.status;
1922 		if (rc == 0)
1923 			break;
1924 		if (rc == -2) {
1925 			printk(KERN_INFO "Increasing MCA rendezvous timeout from "
1926 				"%ld to %ld milliseconds\n", timeout, isrv.v0);
1927 			timeout = isrv.v0;
1928 			NOTIFY_MCA(DIE_MCA_NEW_TIMEOUT, NULL, timeout, 0);
1929 			continue;
1930 		}
1931 		printk(KERN_ERR "Failed to register rendezvous interrupt "
1932 		       "with SAL (status %ld)\n", rc);
1933 		return;
1934 	}
1935 
1936 	/* Register the wakeup interrupt vector with SAL */
1937 	isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_RENDEZ_WAKEUP,
1938 				      SAL_MC_PARAM_MECHANISM_INT,
1939 				      IA64_MCA_WAKEUP_VECTOR,
1940 				      0, 0);
1941 	rc = isrv.status;
1942 	if (rc) {
1943 		printk(KERN_ERR "Failed to register wakeup interrupt with SAL "
1944 		       "(status %ld)\n", rc);
1945 		return;
1946 	}
1947 
1948 	IA64_MCA_DEBUG("%s: registered MCA rendezvous spinloop and wakeup mech.\n", __func__);
1949 
1950 	ia64_mc_info.imi_mca_handler        = ia64_tpa(mca_hldlr_ptr->fp);
1951 	/*
1952 	 * XXX - disable SAL checksum by setting size to 0; should be
1953 	 *	ia64_tpa(ia64_os_mca_dispatch_end) - ia64_tpa(ia64_os_mca_dispatch);
1954 	 */
1955 	ia64_mc_info.imi_mca_handler_size	= 0;
1956 
1957 	/* Register the os mca handler with SAL */
1958 	if ((rc = ia64_sal_set_vectors(SAL_VECTOR_OS_MCA,
1959 				       ia64_mc_info.imi_mca_handler,
1960 				       ia64_tpa(mca_hldlr_ptr->gp),
1961 				       ia64_mc_info.imi_mca_handler_size,
1962 				       0, 0, 0)))
1963 	{
1964 		printk(KERN_ERR "Failed to register OS MCA handler with SAL "
1965 		       "(status %ld)\n", rc);
1966 		return;
1967 	}
1968 
1969 	IA64_MCA_DEBUG("%s: registered OS MCA handler with SAL at 0x%lx, gp = 0x%lx\n", __func__,
1970 		       ia64_mc_info.imi_mca_handler, ia64_tpa(mca_hldlr_ptr->gp));
1971 
1972 	/*
1973 	 * XXX - disable SAL checksum by setting size to 0, should be
1974 	 * size of the actual init handler in mca_asm.S.
1975 	 */
1976 	ia64_mc_info.imi_monarch_init_handler		= ia64_tpa(init_hldlr_ptr_monarch->fp);
1977 	ia64_mc_info.imi_monarch_init_handler_size	= 0;
1978 	ia64_mc_info.imi_slave_init_handler		= ia64_tpa(init_hldlr_ptr_slave->fp);
1979 	ia64_mc_info.imi_slave_init_handler_size	= 0;
1980 
1981 	IA64_MCA_DEBUG("%s: OS INIT handler at %lx\n", __func__,
1982 		       ia64_mc_info.imi_monarch_init_handler);
1983 
1984 	/* Register the os init handler with SAL */
1985 	if ((rc = ia64_sal_set_vectors(SAL_VECTOR_OS_INIT,
1986 				       ia64_mc_info.imi_monarch_init_handler,
1987 				       ia64_tpa(ia64_getreg(_IA64_REG_GP)),
1988 				       ia64_mc_info.imi_monarch_init_handler_size,
1989 				       ia64_mc_info.imi_slave_init_handler,
1990 				       ia64_tpa(ia64_getreg(_IA64_REG_GP)),
1991 				       ia64_mc_info.imi_slave_init_handler_size)))
1992 	{
1993 		printk(KERN_ERR "Failed to register m/s INIT handlers with SAL "
1994 		       "(status %ld)\n", rc);
1995 		return;
1996 	}
1997 	if (register_die_notifier(&default_init_monarch_nb)) {
1998 		printk(KERN_ERR "Failed to register default monarch INIT process\n");
1999 		return;
2000 	}
2001 
2002 	IA64_MCA_DEBUG("%s: registered OS INIT handler with SAL\n", __func__);
2003 
2004 	/* Initialize the areas set aside by the OS to buffer the
2005 	 * platform/processor error states for MCA/INIT/CMC
2006 	 * handling.
2007 	 */
2008 	ia64_log_init(SAL_INFO_TYPE_MCA);
2009 	ia64_log_init(SAL_INFO_TYPE_INIT);
2010 	ia64_log_init(SAL_INFO_TYPE_CMC);
2011 	ia64_log_init(SAL_INFO_TYPE_CPE);
2012 
2013 	mca_init = 1;
2014 	printk(KERN_INFO "MCA related initialization done\n");
2015 }
2016 
2017 
2018 /*
2019  * These pieces cannot be done in ia64_mca_init() because it is called before
2020  * early_irq_init() which would wipe out our percpu irq registrations. But we
2021  * cannot leave them until ia64_mca_late_init() because by then all the other
2022  * processors have been brought online and have set their own CMC vectors to
2023  * point at a non-existant action. Called from arch_early_irq_init().
2024  */
2025 void __init ia64_mca_irq_init(void)
2026 {
2027 	/*
2028 	 *  Configure the CMCI/P vector and handler. Interrupts for CMC are
2029 	 *  per-processor, so AP CMC interrupts are setup in smp_callin() (smpboot.c).
2030 	 */
2031 	register_percpu_irq(IA64_CMC_VECTOR, ia64_mca_cmc_int_handler, 0,
2032 			    "cmc_hndlr");
2033 	register_percpu_irq(IA64_CMCP_VECTOR, ia64_mca_cmc_int_caller, 0,
2034 			    "cmc_poll");
2035 	ia64_mca_cmc_vector_setup();       /* Setup vector on BSP */
2036 
2037 	/* Setup the MCA rendezvous interrupt vector */
2038 	register_percpu_irq(IA64_MCA_RENDEZ_VECTOR, ia64_mca_rendez_int_handler,
2039 			    0, "mca_rdzv");
2040 
2041 	/* Setup the MCA wakeup interrupt vector */
2042 	register_percpu_irq(IA64_MCA_WAKEUP_VECTOR, ia64_mca_wakeup_int_handler,
2043 			    0, "mca_wkup");
2044 
2045 	/* Setup the CPEI/P handler */
2046 	register_percpu_irq(IA64_CPEP_VECTOR, ia64_mca_cpe_int_caller, 0,
2047 			    "cpe_poll");
2048 }
2049 
2050 /*
2051  * ia64_mca_late_init
2052  *
2053  *	Opportunity to setup things that require initialization later
2054  *	than ia64_mca_init.  Setup a timer to poll for CPEs if the
2055  *	platform doesn't support an interrupt driven mechanism.
2056  *
2057  *  Inputs  :   None
2058  *  Outputs :   Status
2059  */
2060 static int __init
2061 ia64_mca_late_init(void)
2062 {
2063 	if (!mca_init)
2064 		return 0;
2065 
2066 	/* Setup the CMCI/P vector and handler */
2067 	timer_setup(&cmc_poll_timer, ia64_mca_cmc_poll, 0);
2068 
2069 	/* Unmask/enable the vector */
2070 	cmc_polling_enabled = 0;
2071 	cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "ia64/mca:online",
2072 			  ia64_mca_cpu_online, NULL);
2073 	IA64_MCA_DEBUG("%s: CMCI/P setup and enabled.\n", __func__);
2074 
2075 	/* Setup the CPEI/P vector and handler */
2076 	cpe_vector = acpi_request_vector(ACPI_INTERRUPT_CPEI);
2077 	timer_setup(&cpe_poll_timer, ia64_mca_cpe_poll, 0);
2078 
2079 	{
2080 		unsigned int irq;
2081 
2082 		if (cpe_vector >= 0) {
2083 			/* If platform supports CPEI, enable the irq. */
2084 			irq = local_vector_to_irq(cpe_vector);
2085 			if (irq > 0) {
2086 				cpe_poll_enabled = 0;
2087 				irq_set_status_flags(irq, IRQ_PER_CPU);
2088 				if (request_irq(irq, ia64_mca_cpe_int_handler,
2089 						0, "cpe_hndlr", NULL))
2090 					pr_err("Failed to register cpe_hndlr interrupt\n");
2091 				ia64_cpe_irq = irq;
2092 				ia64_mca_register_cpev(cpe_vector);
2093 				IA64_MCA_DEBUG("%s: CPEI/P setup and enabled.\n",
2094 					__func__);
2095 				return 0;
2096 			}
2097 			printk(KERN_ERR "%s: Failed to find irq for CPE "
2098 					"interrupt handler, vector %d\n",
2099 					__func__, cpe_vector);
2100 		}
2101 		/* If platform doesn't support CPEI, get the timer going. */
2102 		if (cpe_poll_enabled) {
2103 			ia64_mca_cpe_poll(0UL);
2104 			IA64_MCA_DEBUG("%s: CPEP setup and enabled.\n", __func__);
2105 		}
2106 	}
2107 
2108 	return 0;
2109 }
2110 
2111 device_initcall(ia64_mca_late_init);
2112