xref: /openbmc/linux/arch/ia64/kernel/mca.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
1 /*
2  * File:	mca.c
3  * Purpose:	Generic MCA handling layer
4  *
5  * Updated for latest kernel
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 Silicon Graphics, Inc.
22  * Copyright (C) Vijay Chander(vijay@engr.sgi.com)
23  *
24  * 03/04/15 D. Mosberger Added INIT backtrace support.
25  * 02/03/25 M. Domsch	GUID cleanups
26  *
27  * 02/01/04 J. Hall	Aligned MCA stack to 16 bytes, added platform vs. CPU
28  *			error flag, set SAL default return values, changed
29  *			error record structure to linked list, added init call
30  *			to sal_get_state_info_size().
31  *
32  * 01/01/03 F. Lewis    Added setup of CMCI and CPEI IRQs, logging of corrected
33  *                      platform errors, completed code for logging of
34  *                      corrected & uncorrected machine check errors, and
35  *                      updated for conformance with Nov. 2000 revision of the
36  *                      SAL 3.0 spec.
37  * 00/03/29 C. Fleckenstein  Fixed PAL/SAL update issues, began MCA bug fixes, logging issues,
38  *                           added min save state dump, added INIT handler.
39  *
40  * 2003-12-08 Keith Owens <kaos@sgi.com>
41  *            smp_call_function() must not be called from interrupt context (can
42  *            deadlock on tasklist_lock).  Use keventd to call smp_call_function().
43  *
44  * 2004-02-01 Keith Owens <kaos@sgi.com>
45  *            Avoid deadlock when using printk() for MCA and INIT records.
46  *            Delete all record printing code, moved to salinfo_decode in user space.
47  *            Mark variables and functions static where possible.
48  *            Delete dead variables and functions.
49  *            Reorder to remove the need for forward declarations and to consolidate
50  *            related code.
51  *
52  * 2005-08-12 Keith Owens <kaos@sgi.com>
53  *	      Convert MCA/INIT handlers to use per event stacks and SAL/OS state.
54  *
55  * 2005-10-07 Keith Owens <kaos@sgi.com>
56  *	      Add notify_die() hooks.
57  *
58  * 2006-09-15 Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
59  * 	      Add printing support for MCA/INIT.
60  *
61  * 2007-04-27 Russ Anderson <rja@sgi.com>
62  *	      Support multiple cpus going through OS_MCA in the same event.
63  */
64 #include <linux/types.h>
65 #include <linux/init.h>
66 #include <linux/sched.h>
67 #include <linux/interrupt.h>
68 #include <linux/irq.h>
69 #include <linux/bootmem.h>
70 #include <linux/acpi.h>
71 #include <linux/timer.h>
72 #include <linux/module.h>
73 #include <linux/kernel.h>
74 #include <linux/smp.h>
75 #include <linux/workqueue.h>
76 #include <linux/cpumask.h>
77 #include <linux/kdebug.h>
78 
79 #include <asm/delay.h>
80 #include <asm/machvec.h>
81 #include <asm/meminit.h>
82 #include <asm/page.h>
83 #include <asm/ptrace.h>
84 #include <asm/system.h>
85 #include <asm/sal.h>
86 #include <asm/mca.h>
87 #include <asm/kexec.h>
88 
89 #include <asm/irq.h>
90 #include <asm/hw_irq.h>
91 
92 #include "mca_drv.h"
93 #include "entry.h"
94 
95 #if defined(IA64_MCA_DEBUG_INFO)
96 # define IA64_MCA_DEBUG(fmt...)	printk(fmt)
97 #else
98 # define IA64_MCA_DEBUG(fmt...)
99 #endif
100 
101 /* Used by mca_asm.S */
102 DEFINE_PER_CPU(u64, ia64_mca_data); /* == __per_cpu_mca[smp_processor_id()] */
103 DEFINE_PER_CPU(u64, ia64_mca_per_cpu_pte); /* PTE to map per-CPU area */
104 DEFINE_PER_CPU(u64, ia64_mca_pal_pte);	    /* PTE to map PAL code */
105 DEFINE_PER_CPU(u64, ia64_mca_pal_base);    /* vaddr PAL code granule */
106 
107 unsigned long __per_cpu_mca[NR_CPUS];
108 
109 /* In mca_asm.S */
110 extern void			ia64_os_init_dispatch_monarch (void);
111 extern void			ia64_os_init_dispatch_slave (void);
112 
113 static int monarch_cpu = -1;
114 
115 static ia64_mc_info_t		ia64_mc_info;
116 
117 #define MAX_CPE_POLL_INTERVAL (15*60*HZ) /* 15 minutes */
118 #define MIN_CPE_POLL_INTERVAL (2*60*HZ)  /* 2 minutes */
119 #define CMC_POLL_INTERVAL     (1*60*HZ)  /* 1 minute */
120 #define CPE_HISTORY_LENGTH    5
121 #define CMC_HISTORY_LENGTH    5
122 
123 #ifdef CONFIG_ACPI
124 static struct timer_list cpe_poll_timer;
125 #endif
126 static struct timer_list cmc_poll_timer;
127 /*
128  * This variable tells whether we are currently in polling mode.
129  * Start with this in the wrong state so we won't play w/ timers
130  * before the system is ready.
131  */
132 static int cmc_polling_enabled = 1;
133 
134 /*
135  * Clearing this variable prevents CPE polling from getting activated
136  * in mca_late_init.  Use it if your system doesn't provide a CPEI,
137  * but encounters problems retrieving CPE logs.  This should only be
138  * necessary for debugging.
139  */
140 static int cpe_poll_enabled = 1;
141 
142 extern void salinfo_log_wakeup(int type, u8 *buffer, u64 size, int irqsafe);
143 
144 static int mca_init __initdata;
145 
146 /*
147  * limited & delayed printing support for MCA/INIT handler
148  */
149 
150 #define mprintk(fmt...) ia64_mca_printk(fmt)
151 
152 #define MLOGBUF_SIZE (512+256*NR_CPUS)
153 #define MLOGBUF_MSGMAX 256
154 static char mlogbuf[MLOGBUF_SIZE];
155 static DEFINE_SPINLOCK(mlogbuf_wlock);	/* mca context only */
156 static DEFINE_SPINLOCK(mlogbuf_rlock);	/* normal context only */
157 static unsigned long mlogbuf_start;
158 static unsigned long mlogbuf_end;
159 static unsigned int mlogbuf_finished = 0;
160 static unsigned long mlogbuf_timestamp = 0;
161 
162 static int loglevel_save = -1;
163 #define BREAK_LOGLEVEL(__console_loglevel)		\
164 	oops_in_progress = 1;				\
165 	if (loglevel_save < 0)				\
166 		loglevel_save = __console_loglevel;	\
167 	__console_loglevel = 15;
168 
169 #define RESTORE_LOGLEVEL(__console_loglevel)		\
170 	if (loglevel_save >= 0) {			\
171 		__console_loglevel = loglevel_save;	\
172 		loglevel_save = -1;			\
173 	}						\
174 	mlogbuf_finished = 0;				\
175 	oops_in_progress = 0;
176 
177 /*
178  * Push messages into buffer, print them later if not urgent.
179  */
180 void ia64_mca_printk(const char *fmt, ...)
181 {
182 	va_list args;
183 	int printed_len;
184 	char temp_buf[MLOGBUF_MSGMAX];
185 	char *p;
186 
187 	va_start(args, fmt);
188 	printed_len = vscnprintf(temp_buf, sizeof(temp_buf), fmt, args);
189 	va_end(args);
190 
191 	/* Copy the output into mlogbuf */
192 	if (oops_in_progress) {
193 		/* mlogbuf was abandoned, use printk directly instead. */
194 		printk(temp_buf);
195 	} else {
196 		spin_lock(&mlogbuf_wlock);
197 		for (p = temp_buf; *p; p++) {
198 			unsigned long next = (mlogbuf_end + 1) % MLOGBUF_SIZE;
199 			if (next != mlogbuf_start) {
200 				mlogbuf[mlogbuf_end] = *p;
201 				mlogbuf_end = next;
202 			} else {
203 				/* buffer full */
204 				break;
205 			}
206 		}
207 		mlogbuf[mlogbuf_end] = '\0';
208 		spin_unlock(&mlogbuf_wlock);
209 	}
210 }
211 EXPORT_SYMBOL(ia64_mca_printk);
212 
213 /*
214  * Print buffered messages.
215  *  NOTE: call this after returning normal context. (ex. from salinfod)
216  */
217 void ia64_mlogbuf_dump(void)
218 {
219 	char temp_buf[MLOGBUF_MSGMAX];
220 	char *p;
221 	unsigned long index;
222 	unsigned long flags;
223 	unsigned int printed_len;
224 
225 	/* Get output from mlogbuf */
226 	while (mlogbuf_start != mlogbuf_end) {
227 		temp_buf[0] = '\0';
228 		p = temp_buf;
229 		printed_len = 0;
230 
231 		spin_lock_irqsave(&mlogbuf_rlock, flags);
232 
233 		index = mlogbuf_start;
234 		while (index != mlogbuf_end) {
235 			*p = mlogbuf[index];
236 			index = (index + 1) % MLOGBUF_SIZE;
237 			if (!*p)
238 				break;
239 			p++;
240 			if (++printed_len >= MLOGBUF_MSGMAX - 1)
241 				break;
242 		}
243 		*p = '\0';
244 		if (temp_buf[0])
245 			printk(temp_buf);
246 		mlogbuf_start = index;
247 
248 		mlogbuf_timestamp = 0;
249 		spin_unlock_irqrestore(&mlogbuf_rlock, flags);
250 	}
251 }
252 EXPORT_SYMBOL(ia64_mlogbuf_dump);
253 
254 /*
255  * Call this if system is going to down or if immediate flushing messages to
256  * console is required. (ex. recovery was failed, crash dump is going to be
257  * invoked, long-wait rendezvous etc.)
258  *  NOTE: this should be called from monarch.
259  */
260 static void ia64_mlogbuf_finish(int wait)
261 {
262 	BREAK_LOGLEVEL(console_loglevel);
263 
264 	spin_lock_init(&mlogbuf_rlock);
265 	ia64_mlogbuf_dump();
266 	printk(KERN_EMERG "mlogbuf_finish: printing switched to urgent mode, "
267 		"MCA/INIT might be dodgy or fail.\n");
268 
269 	if (!wait)
270 		return;
271 
272 	/* wait for console */
273 	printk("Delaying for 5 seconds...\n");
274 	udelay(5*1000000);
275 
276 	mlogbuf_finished = 1;
277 }
278 
279 /*
280  * Print buffered messages from INIT context.
281  */
282 static void ia64_mlogbuf_dump_from_init(void)
283 {
284 	if (mlogbuf_finished)
285 		return;
286 
287 	if (mlogbuf_timestamp && (mlogbuf_timestamp + 30*HZ > jiffies)) {
288 		printk(KERN_ERR "INIT: mlogbuf_dump is interrupted by INIT "
289 			" and the system seems to be messed up.\n");
290 		ia64_mlogbuf_finish(0);
291 		return;
292 	}
293 
294 	if (!spin_trylock(&mlogbuf_rlock)) {
295 		printk(KERN_ERR "INIT: mlogbuf_dump is interrupted by INIT. "
296 			"Generated messages other than stack dump will be "
297 			"buffered to mlogbuf and will be printed later.\n");
298 		printk(KERN_ERR "INIT: If messages would not printed after "
299 			"this INIT, wait 30sec and assert INIT again.\n");
300 		if (!mlogbuf_timestamp)
301 			mlogbuf_timestamp = jiffies;
302 		return;
303 	}
304 	spin_unlock(&mlogbuf_rlock);
305 	ia64_mlogbuf_dump();
306 }
307 
308 static void inline
309 ia64_mca_spin(const char *func)
310 {
311 	if (monarch_cpu == smp_processor_id())
312 		ia64_mlogbuf_finish(0);
313 	mprintk(KERN_EMERG "%s: spinning here, not returning to SAL\n", func);
314 	while (1)
315 		cpu_relax();
316 }
317 /*
318  * IA64_MCA log support
319  */
320 #define IA64_MAX_LOGS		2	/* Double-buffering for nested MCAs */
321 #define IA64_MAX_LOG_TYPES      4   /* MCA, INIT, CMC, CPE */
322 
323 typedef struct ia64_state_log_s
324 {
325 	spinlock_t	isl_lock;
326 	int		isl_index;
327 	unsigned long	isl_count;
328 	ia64_err_rec_t  *isl_log[IA64_MAX_LOGS]; /* need space to store header + error log */
329 } ia64_state_log_t;
330 
331 static ia64_state_log_t ia64_state_log[IA64_MAX_LOG_TYPES];
332 
333 #define IA64_LOG_ALLOCATE(it, size) \
334 	{ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)] = \
335 		(ia64_err_rec_t *)alloc_bootmem(size); \
336 	ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)] = \
337 		(ia64_err_rec_t *)alloc_bootmem(size);}
338 #define IA64_LOG_LOCK_INIT(it) spin_lock_init(&ia64_state_log[it].isl_lock)
339 #define IA64_LOG_LOCK(it)      spin_lock_irqsave(&ia64_state_log[it].isl_lock, s)
340 #define IA64_LOG_UNLOCK(it)    spin_unlock_irqrestore(&ia64_state_log[it].isl_lock,s)
341 #define IA64_LOG_NEXT_INDEX(it)    ia64_state_log[it].isl_index
342 #define IA64_LOG_CURR_INDEX(it)    1 - ia64_state_log[it].isl_index
343 #define IA64_LOG_INDEX_INC(it) \
344     {ia64_state_log[it].isl_index = 1 - ia64_state_log[it].isl_index; \
345     ia64_state_log[it].isl_count++;}
346 #define IA64_LOG_INDEX_DEC(it) \
347     ia64_state_log[it].isl_index = 1 - ia64_state_log[it].isl_index
348 #define IA64_LOG_NEXT_BUFFER(it)   (void *)((ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)]))
349 #define IA64_LOG_CURR_BUFFER(it)   (void *)((ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)]))
350 #define IA64_LOG_COUNT(it)         ia64_state_log[it].isl_count
351 
352 /*
353  * ia64_log_init
354  *	Reset the OS ia64 log buffer
355  * Inputs   :   info_type   (SAL_INFO_TYPE_{MCA,INIT,CMC,CPE})
356  * Outputs	:	None
357  */
358 static void __init
359 ia64_log_init(int sal_info_type)
360 {
361 	u64	max_size = 0;
362 
363 	IA64_LOG_NEXT_INDEX(sal_info_type) = 0;
364 	IA64_LOG_LOCK_INIT(sal_info_type);
365 
366 	// SAL will tell us the maximum size of any error record of this type
367 	max_size = ia64_sal_get_state_info_size(sal_info_type);
368 	if (!max_size)
369 		/* alloc_bootmem() doesn't like zero-sized allocations! */
370 		return;
371 
372 	// set up OS data structures to hold error info
373 	IA64_LOG_ALLOCATE(sal_info_type, max_size);
374 	memset(IA64_LOG_CURR_BUFFER(sal_info_type), 0, max_size);
375 	memset(IA64_LOG_NEXT_BUFFER(sal_info_type), 0, max_size);
376 }
377 
378 /*
379  * ia64_log_get
380  *
381  *	Get the current MCA log from SAL and copy it into the OS log buffer.
382  *
383  *  Inputs  :   info_type   (SAL_INFO_TYPE_{MCA,INIT,CMC,CPE})
384  *              irq_safe    whether you can use printk at this point
385  *  Outputs :   size        (total record length)
386  *              *buffer     (ptr to error record)
387  *
388  */
389 static u64
390 ia64_log_get(int sal_info_type, u8 **buffer, int irq_safe)
391 {
392 	sal_log_record_header_t     *log_buffer;
393 	u64                         total_len = 0;
394 	unsigned long               s;
395 
396 	IA64_LOG_LOCK(sal_info_type);
397 
398 	/* Get the process state information */
399 	log_buffer = IA64_LOG_NEXT_BUFFER(sal_info_type);
400 
401 	total_len = ia64_sal_get_state_info(sal_info_type, (u64 *)log_buffer);
402 
403 	if (total_len) {
404 		IA64_LOG_INDEX_INC(sal_info_type);
405 		IA64_LOG_UNLOCK(sal_info_type);
406 		if (irq_safe) {
407 			IA64_MCA_DEBUG("%s: SAL error record type %d retrieved. "
408 				       "Record length = %ld\n", __FUNCTION__, sal_info_type, total_len);
409 		}
410 		*buffer = (u8 *) log_buffer;
411 		return total_len;
412 	} else {
413 		IA64_LOG_UNLOCK(sal_info_type);
414 		return 0;
415 	}
416 }
417 
418 /*
419  *  ia64_mca_log_sal_error_record
420  *
421  *  This function retrieves a specified error record type from SAL
422  *  and wakes up any processes waiting for error records.
423  *
424  *  Inputs  :   sal_info_type   (Type of error record MCA/CMC/CPE)
425  *              FIXME: remove MCA and irq_safe.
426  */
427 static void
428 ia64_mca_log_sal_error_record(int sal_info_type)
429 {
430 	u8 *buffer;
431 	sal_log_record_header_t *rh;
432 	u64 size;
433 	int irq_safe = sal_info_type != SAL_INFO_TYPE_MCA;
434 #ifdef IA64_MCA_DEBUG_INFO
435 	static const char * const rec_name[] = { "MCA", "INIT", "CMC", "CPE" };
436 #endif
437 
438 	size = ia64_log_get(sal_info_type, &buffer, irq_safe);
439 	if (!size)
440 		return;
441 
442 	salinfo_log_wakeup(sal_info_type, buffer, size, irq_safe);
443 
444 	if (irq_safe)
445 		IA64_MCA_DEBUG("CPU %d: SAL log contains %s error record\n",
446 			smp_processor_id(),
447 			sal_info_type < ARRAY_SIZE(rec_name) ? rec_name[sal_info_type] : "UNKNOWN");
448 
449 	/* Clear logs from corrected errors in case there's no user-level logger */
450 	rh = (sal_log_record_header_t *)buffer;
451 	if (rh->severity == sal_log_severity_corrected)
452 		ia64_sal_clear_state_info(sal_info_type);
453 }
454 
455 /*
456  * search_mca_table
457  *  See if the MCA surfaced in an instruction range
458  *  that has been tagged as recoverable.
459  *
460  *  Inputs
461  *	first	First address range to check
462  *	last	Last address range to check
463  *	ip	Instruction pointer, address we are looking for
464  *
465  * Return value:
466  *      1 on Success (in the table)/ 0 on Failure (not in the  table)
467  */
468 int
469 search_mca_table (const struct mca_table_entry *first,
470                 const struct mca_table_entry *last,
471                 unsigned long ip)
472 {
473         const struct mca_table_entry *curr;
474         u64 curr_start, curr_end;
475 
476         curr = first;
477         while (curr <= last) {
478                 curr_start = (u64) &curr->start_addr + curr->start_addr;
479                 curr_end = (u64) &curr->end_addr + curr->end_addr;
480 
481                 if ((ip >= curr_start) && (ip <= curr_end)) {
482                         return 1;
483                 }
484                 curr++;
485         }
486         return 0;
487 }
488 
489 /* Given an address, look for it in the mca tables. */
490 int mca_recover_range(unsigned long addr)
491 {
492 	extern struct mca_table_entry __start___mca_table[];
493 	extern struct mca_table_entry __stop___mca_table[];
494 
495 	return search_mca_table(__start___mca_table, __stop___mca_table-1, addr);
496 }
497 EXPORT_SYMBOL_GPL(mca_recover_range);
498 
499 #ifdef CONFIG_ACPI
500 
501 int cpe_vector = -1;
502 int ia64_cpe_irq = -1;
503 
504 static irqreturn_t
505 ia64_mca_cpe_int_handler (int cpe_irq, void *arg)
506 {
507 	static unsigned long	cpe_history[CPE_HISTORY_LENGTH];
508 	static int		index;
509 	static DEFINE_SPINLOCK(cpe_history_lock);
510 
511 	IA64_MCA_DEBUG("%s: received interrupt vector = %#x on CPU %d\n",
512 		       __FUNCTION__, cpe_irq, smp_processor_id());
513 
514 	/* SAL spec states this should run w/ interrupts enabled */
515 	local_irq_enable();
516 
517 	spin_lock(&cpe_history_lock);
518 	if (!cpe_poll_enabled && cpe_vector >= 0) {
519 
520 		int i, count = 1; /* we know 1 happened now */
521 		unsigned long now = jiffies;
522 
523 		for (i = 0; i < CPE_HISTORY_LENGTH; i++) {
524 			if (now - cpe_history[i] <= HZ)
525 				count++;
526 		}
527 
528 		IA64_MCA_DEBUG(KERN_INFO "CPE threshold %d/%d\n", count, CPE_HISTORY_LENGTH);
529 		if (count >= CPE_HISTORY_LENGTH) {
530 
531 			cpe_poll_enabled = 1;
532 			spin_unlock(&cpe_history_lock);
533 			disable_irq_nosync(local_vector_to_irq(IA64_CPE_VECTOR));
534 
535 			/*
536 			 * Corrected errors will still be corrected, but
537 			 * make sure there's a log somewhere that indicates
538 			 * something is generating more than we can handle.
539 			 */
540 			printk(KERN_WARNING "WARNING: Switching to polling CPE handler; error records may be lost\n");
541 
542 			mod_timer(&cpe_poll_timer, jiffies + MIN_CPE_POLL_INTERVAL);
543 
544 			/* lock already released, get out now */
545 			goto out;
546 		} else {
547 			cpe_history[index++] = now;
548 			if (index == CPE_HISTORY_LENGTH)
549 				index = 0;
550 		}
551 	}
552 	spin_unlock(&cpe_history_lock);
553 out:
554 	/* Get the CPE error record and log it */
555 	ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CPE);
556 
557 	return IRQ_HANDLED;
558 }
559 
560 #endif /* CONFIG_ACPI */
561 
562 #ifdef CONFIG_ACPI
563 /*
564  * ia64_mca_register_cpev
565  *
566  *  Register the corrected platform error vector with SAL.
567  *
568  *  Inputs
569  *      cpev        Corrected Platform Error Vector number
570  *
571  *  Outputs
572  *      None
573  */
574 static void __init
575 ia64_mca_register_cpev (int cpev)
576 {
577 	/* Register the CPE interrupt vector with SAL */
578 	struct ia64_sal_retval isrv;
579 
580 	isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_CPE_INT, SAL_MC_PARAM_MECHANISM_INT, cpev, 0, 0);
581 	if (isrv.status) {
582 		printk(KERN_ERR "Failed to register Corrected Platform "
583 		       "Error interrupt vector with SAL (status %ld)\n", isrv.status);
584 		return;
585 	}
586 
587 	IA64_MCA_DEBUG("%s: corrected platform error "
588 		       "vector %#x registered\n", __FUNCTION__, cpev);
589 }
590 #endif /* CONFIG_ACPI */
591 
592 /*
593  * ia64_mca_cmc_vector_setup
594  *
595  *  Setup the corrected machine check vector register in the processor.
596  *  (The interrupt is masked on boot. ia64_mca_late_init unmask this.)
597  *  This function is invoked on a per-processor basis.
598  *
599  * Inputs
600  *      None
601  *
602  * Outputs
603  *	None
604  */
605 void __cpuinit
606 ia64_mca_cmc_vector_setup (void)
607 {
608 	cmcv_reg_t	cmcv;
609 
610 	cmcv.cmcv_regval	= 0;
611 	cmcv.cmcv_mask		= 1;        /* Mask/disable interrupt at first */
612 	cmcv.cmcv_vector	= IA64_CMC_VECTOR;
613 	ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
614 
615 	IA64_MCA_DEBUG("%s: CPU %d corrected "
616 		       "machine check vector %#x registered.\n",
617 		       __FUNCTION__, smp_processor_id(), IA64_CMC_VECTOR);
618 
619 	IA64_MCA_DEBUG("%s: CPU %d CMCV = %#016lx\n",
620 		       __FUNCTION__, smp_processor_id(), ia64_getreg(_IA64_REG_CR_CMCV));
621 }
622 
623 /*
624  * ia64_mca_cmc_vector_disable
625  *
626  *  Mask the corrected machine check vector register in the processor.
627  *  This function is invoked on a per-processor basis.
628  *
629  * Inputs
630  *      dummy(unused)
631  *
632  * Outputs
633  *	None
634  */
635 static void
636 ia64_mca_cmc_vector_disable (void *dummy)
637 {
638 	cmcv_reg_t	cmcv;
639 
640 	cmcv.cmcv_regval = ia64_getreg(_IA64_REG_CR_CMCV);
641 
642 	cmcv.cmcv_mask = 1; /* Mask/disable interrupt */
643 	ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
644 
645 	IA64_MCA_DEBUG("%s: CPU %d corrected "
646 		       "machine check vector %#x disabled.\n",
647 		       __FUNCTION__, smp_processor_id(), cmcv.cmcv_vector);
648 }
649 
650 /*
651  * ia64_mca_cmc_vector_enable
652  *
653  *  Unmask the corrected machine check vector register in the processor.
654  *  This function is invoked on a per-processor basis.
655  *
656  * Inputs
657  *      dummy(unused)
658  *
659  * Outputs
660  *	None
661  */
662 static void
663 ia64_mca_cmc_vector_enable (void *dummy)
664 {
665 	cmcv_reg_t	cmcv;
666 
667 	cmcv.cmcv_regval = ia64_getreg(_IA64_REG_CR_CMCV);
668 
669 	cmcv.cmcv_mask = 0; /* Unmask/enable interrupt */
670 	ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
671 
672 	IA64_MCA_DEBUG("%s: CPU %d corrected "
673 		       "machine check vector %#x enabled.\n",
674 		       __FUNCTION__, smp_processor_id(), cmcv.cmcv_vector);
675 }
676 
677 /*
678  * ia64_mca_cmc_vector_disable_keventd
679  *
680  * Called via keventd (smp_call_function() is not safe in interrupt context) to
681  * disable the cmc interrupt vector.
682  */
683 static void
684 ia64_mca_cmc_vector_disable_keventd(struct work_struct *unused)
685 {
686 	on_each_cpu(ia64_mca_cmc_vector_disable, NULL, 1, 0);
687 }
688 
689 /*
690  * ia64_mca_cmc_vector_enable_keventd
691  *
692  * Called via keventd (smp_call_function() is not safe in interrupt context) to
693  * enable the cmc interrupt vector.
694  */
695 static void
696 ia64_mca_cmc_vector_enable_keventd(struct work_struct *unused)
697 {
698 	on_each_cpu(ia64_mca_cmc_vector_enable, NULL, 1, 0);
699 }
700 
701 /*
702  * ia64_mca_wakeup
703  *
704  *	Send an inter-cpu interrupt to wake-up a particular cpu.
705  *
706  *  Inputs  :   cpuid
707  *  Outputs :   None
708  */
709 static void
710 ia64_mca_wakeup(int cpu)
711 {
712 	platform_send_ipi(cpu, IA64_MCA_WAKEUP_VECTOR, IA64_IPI_DM_INT, 0);
713 }
714 
715 /*
716  * ia64_mca_wakeup_all
717  *
718  *	Wakeup all the slave cpus which have rendez'ed previously.
719  *
720  *  Inputs  :   None
721  *  Outputs :   None
722  */
723 static void
724 ia64_mca_wakeup_all(void)
725 {
726 	int cpu;
727 
728 	/* Clear the Rendez checkin flag for all cpus */
729 	for_each_online_cpu(cpu) {
730 		if (ia64_mc_info.imi_rendez_checkin[cpu] == IA64_MCA_RENDEZ_CHECKIN_DONE)
731 			ia64_mca_wakeup(cpu);
732 	}
733 
734 }
735 
736 /*
737  * ia64_mca_rendez_interrupt_handler
738  *
739  *	This is handler used to put slave processors into spinloop
740  *	while the monarch processor does the mca handling and later
741  *	wake each slave up once the monarch is done.  The state
742  *	IA64_MCA_RENDEZ_CHECKIN_DONE indicates the cpu is rendez'ed
743  *	in SAL.  The state IA64_MCA_RENDEZ_CHECKIN_NOTDONE indicates
744  *	the cpu has come out of OS rendezvous.
745  *
746  *  Inputs  :   None
747  *  Outputs :   None
748  */
749 static irqreturn_t
750 ia64_mca_rendez_int_handler(int rendez_irq, void *arg)
751 {
752 	unsigned long flags;
753 	int cpu = smp_processor_id();
754 	struct ia64_mca_notify_die nd =
755 		{ .sos = NULL, .monarch_cpu = &monarch_cpu };
756 
757 	/* Mask all interrupts */
758 	local_irq_save(flags);
759 	if (notify_die(DIE_MCA_RENDZVOUS_ENTER, "MCA", get_irq_regs(),
760 		       (long)&nd, 0, 0) == NOTIFY_STOP)
761 		ia64_mca_spin(__FUNCTION__);
762 
763 	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_DONE;
764 	/* Register with the SAL monarch that the slave has
765 	 * reached SAL
766 	 */
767 	ia64_sal_mc_rendez();
768 
769 	if (notify_die(DIE_MCA_RENDZVOUS_PROCESS, "MCA", get_irq_regs(),
770 		       (long)&nd, 0, 0) == NOTIFY_STOP)
771 		ia64_mca_spin(__FUNCTION__);
772 
773 	/* Wait for the monarch cpu to exit. */
774 	while (monarch_cpu != -1)
775 	       cpu_relax();	/* spin until monarch leaves */
776 
777 	if (notify_die(DIE_MCA_RENDZVOUS_LEAVE, "MCA", get_irq_regs(),
778 		       (long)&nd, 0, 0) == NOTIFY_STOP)
779 		ia64_mca_spin(__FUNCTION__);
780 
781 	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
782 	/* Enable all interrupts */
783 	local_irq_restore(flags);
784 	return IRQ_HANDLED;
785 }
786 
787 /*
788  * ia64_mca_wakeup_int_handler
789  *
790  *	The interrupt handler for processing the inter-cpu interrupt to the
791  *	slave cpu which was spinning in the rendez loop.
792  *	Since this spinning is done by turning off the interrupts and
793  *	polling on the wakeup-interrupt bit in the IRR, there is
794  *	nothing useful to be done in the handler.
795  *
796  *  Inputs  :   wakeup_irq  (Wakeup-interrupt bit)
797  *	arg		(Interrupt handler specific argument)
798  *  Outputs :   None
799  *
800  */
801 static irqreturn_t
802 ia64_mca_wakeup_int_handler(int wakeup_irq, void *arg)
803 {
804 	return IRQ_HANDLED;
805 }
806 
807 /* Function pointer for extra MCA recovery */
808 int (*ia64_mca_ucmc_extension)
809 	(void*,struct ia64_sal_os_state*)
810 	= NULL;
811 
812 int
813 ia64_reg_MCA_extension(int (*fn)(void *, struct ia64_sal_os_state *))
814 {
815 	if (ia64_mca_ucmc_extension)
816 		return 1;
817 
818 	ia64_mca_ucmc_extension = fn;
819 	return 0;
820 }
821 
822 void
823 ia64_unreg_MCA_extension(void)
824 {
825 	if (ia64_mca_ucmc_extension)
826 		ia64_mca_ucmc_extension = NULL;
827 }
828 
829 EXPORT_SYMBOL(ia64_reg_MCA_extension);
830 EXPORT_SYMBOL(ia64_unreg_MCA_extension);
831 
832 
833 static inline void
834 copy_reg(const u64 *fr, u64 fnat, u64 *tr, u64 *tnat)
835 {
836 	u64 fslot, tslot, nat;
837 	*tr = *fr;
838 	fslot = ((unsigned long)fr >> 3) & 63;
839 	tslot = ((unsigned long)tr >> 3) & 63;
840 	*tnat &= ~(1UL << tslot);
841 	nat = (fnat >> fslot) & 1;
842 	*tnat |= (nat << tslot);
843 }
844 
845 /* Change the comm field on the MCA/INT task to include the pid that
846  * was interrupted, it makes for easier debugging.  If that pid was 0
847  * (swapper or nested MCA/INIT) then use the start of the previous comm
848  * field suffixed with its cpu.
849  */
850 
851 static void
852 ia64_mca_modify_comm(const struct task_struct *previous_current)
853 {
854 	char *p, comm[sizeof(current->comm)];
855 	if (previous_current->pid)
856 		snprintf(comm, sizeof(comm), "%s %d",
857 			current->comm, previous_current->pid);
858 	else {
859 		int l;
860 		if ((p = strchr(previous_current->comm, ' ')))
861 			l = p - previous_current->comm;
862 		else
863 			l = strlen(previous_current->comm);
864 		snprintf(comm, sizeof(comm), "%s %*s %d",
865 			current->comm, l, previous_current->comm,
866 			task_thread_info(previous_current)->cpu);
867 	}
868 	memcpy(current->comm, comm, sizeof(current->comm));
869 }
870 
871 /* On entry to this routine, we are running on the per cpu stack, see
872  * mca_asm.h.  The original stack has not been touched by this event.  Some of
873  * the original stack's registers will be in the RBS on this stack.  This stack
874  * also contains a partial pt_regs and switch_stack, the rest of the data is in
875  * PAL minstate.
876  *
877  * The first thing to do is modify the original stack to look like a blocked
878  * task so we can run backtrace on the original task.  Also mark the per cpu
879  * stack as current to ensure that we use the correct task state, it also means
880  * that we can do backtrace on the MCA/INIT handler code itself.
881  */
882 
883 static struct task_struct *
884 ia64_mca_modify_original_stack(struct pt_regs *regs,
885 		const struct switch_stack *sw,
886 		struct ia64_sal_os_state *sos,
887 		const char *type)
888 {
889 	char *p;
890 	ia64_va va;
891 	extern char ia64_leave_kernel[];	/* Need asm address, not function descriptor */
892 	const pal_min_state_area_t *ms = sos->pal_min_state;
893 	struct task_struct *previous_current;
894 	struct pt_regs *old_regs;
895 	struct switch_stack *old_sw;
896 	unsigned size = sizeof(struct pt_regs) +
897 			sizeof(struct switch_stack) + 16;
898 	u64 *old_bspstore, *old_bsp;
899 	u64 *new_bspstore, *new_bsp;
900 	u64 old_unat, old_rnat, new_rnat, nat;
901 	u64 slots, loadrs = regs->loadrs;
902 	u64 r12 = ms->pmsa_gr[12-1], r13 = ms->pmsa_gr[13-1];
903 	u64 ar_bspstore = regs->ar_bspstore;
904 	u64 ar_bsp = regs->ar_bspstore + (loadrs >> 16);
905 	const u64 *bank;
906 	const char *msg;
907 	int cpu = smp_processor_id();
908 
909 	previous_current = curr_task(cpu);
910 	set_curr_task(cpu, current);
911 	if ((p = strchr(current->comm, ' ')))
912 		*p = '\0';
913 
914 	/* Best effort attempt to cope with MCA/INIT delivered while in
915 	 * physical mode.
916 	 */
917 	regs->cr_ipsr = ms->pmsa_ipsr;
918 	if (ia64_psr(regs)->dt == 0) {
919 		va.l = r12;
920 		if (va.f.reg == 0) {
921 			va.f.reg = 7;
922 			r12 = va.l;
923 		}
924 		va.l = r13;
925 		if (va.f.reg == 0) {
926 			va.f.reg = 7;
927 			r13 = va.l;
928 		}
929 	}
930 	if (ia64_psr(regs)->rt == 0) {
931 		va.l = ar_bspstore;
932 		if (va.f.reg == 0) {
933 			va.f.reg = 7;
934 			ar_bspstore = va.l;
935 		}
936 		va.l = ar_bsp;
937 		if (va.f.reg == 0) {
938 			va.f.reg = 7;
939 			ar_bsp = va.l;
940 		}
941 	}
942 
943 	/* mca_asm.S ia64_old_stack() cannot assume that the dirty registers
944 	 * have been copied to the old stack, the old stack may fail the
945 	 * validation tests below.  So ia64_old_stack() must restore the dirty
946 	 * registers from the new stack.  The old and new bspstore probably
947 	 * have different alignments, so loadrs calculated on the old bsp
948 	 * cannot be used to restore from the new bsp.  Calculate a suitable
949 	 * loadrs for the new stack and save it in the new pt_regs, where
950 	 * ia64_old_stack() can get it.
951 	 */
952 	old_bspstore = (u64 *)ar_bspstore;
953 	old_bsp = (u64 *)ar_bsp;
954 	slots = ia64_rse_num_regs(old_bspstore, old_bsp);
955 	new_bspstore = (u64 *)((u64)current + IA64_RBS_OFFSET);
956 	new_bsp = ia64_rse_skip_regs(new_bspstore, slots);
957 	regs->loadrs = (new_bsp - new_bspstore) * 8 << 16;
958 
959 	/* Verify the previous stack state before we change it */
960 	if (user_mode(regs)) {
961 		msg = "occurred in user space";
962 		/* previous_current is guaranteed to be valid when the task was
963 		 * in user space, so ...
964 		 */
965 		ia64_mca_modify_comm(previous_current);
966 		goto no_mod;
967 	}
968 
969 	if (r13 != sos->prev_IA64_KR_CURRENT) {
970 		msg = "inconsistent previous current and r13";
971 		goto no_mod;
972 	}
973 
974 	if (!mca_recover_range(ms->pmsa_iip)) {
975 		if ((r12 - r13) >= KERNEL_STACK_SIZE) {
976 			msg = "inconsistent r12 and r13";
977 			goto no_mod;
978 		}
979 		if ((ar_bspstore - r13) >= KERNEL_STACK_SIZE) {
980 			msg = "inconsistent ar.bspstore and r13";
981 			goto no_mod;
982 		}
983 		va.p = old_bspstore;
984 		if (va.f.reg < 5) {
985 			msg = "old_bspstore is in the wrong region";
986 			goto no_mod;
987 		}
988 		if ((ar_bsp - r13) >= KERNEL_STACK_SIZE) {
989 			msg = "inconsistent ar.bsp and r13";
990 			goto no_mod;
991 		}
992 		size += (ia64_rse_skip_regs(old_bspstore, slots) - old_bspstore) * 8;
993 		if (ar_bspstore + size > r12) {
994 			msg = "no room for blocked state";
995 			goto no_mod;
996 		}
997 	}
998 
999 	ia64_mca_modify_comm(previous_current);
1000 
1001 	/* Make the original task look blocked.  First stack a struct pt_regs,
1002 	 * describing the state at the time of interrupt.  mca_asm.S built a
1003 	 * partial pt_regs, copy it and fill in the blanks using minstate.
1004 	 */
1005 	p = (char *)r12 - sizeof(*regs);
1006 	old_regs = (struct pt_regs *)p;
1007 	memcpy(old_regs, regs, sizeof(*regs));
1008 	/* If ipsr.ic then use pmsa_{iip,ipsr,ifs}, else use
1009 	 * pmsa_{xip,xpsr,xfs}
1010 	 */
1011 	if (ia64_psr(regs)->ic) {
1012 		old_regs->cr_iip = ms->pmsa_iip;
1013 		old_regs->cr_ipsr = ms->pmsa_ipsr;
1014 		old_regs->cr_ifs = ms->pmsa_ifs;
1015 	} else {
1016 		old_regs->cr_iip = ms->pmsa_xip;
1017 		old_regs->cr_ipsr = ms->pmsa_xpsr;
1018 		old_regs->cr_ifs = ms->pmsa_xfs;
1019 	}
1020 	old_regs->pr = ms->pmsa_pr;
1021 	old_regs->b0 = ms->pmsa_br0;
1022 	old_regs->loadrs = loadrs;
1023 	old_regs->ar_rsc = ms->pmsa_rsc;
1024 	old_unat = old_regs->ar_unat;
1025 	copy_reg(&ms->pmsa_gr[1-1], ms->pmsa_nat_bits, &old_regs->r1, &old_unat);
1026 	copy_reg(&ms->pmsa_gr[2-1], ms->pmsa_nat_bits, &old_regs->r2, &old_unat);
1027 	copy_reg(&ms->pmsa_gr[3-1], ms->pmsa_nat_bits, &old_regs->r3, &old_unat);
1028 	copy_reg(&ms->pmsa_gr[8-1], ms->pmsa_nat_bits, &old_regs->r8, &old_unat);
1029 	copy_reg(&ms->pmsa_gr[9-1], ms->pmsa_nat_bits, &old_regs->r9, &old_unat);
1030 	copy_reg(&ms->pmsa_gr[10-1], ms->pmsa_nat_bits, &old_regs->r10, &old_unat);
1031 	copy_reg(&ms->pmsa_gr[11-1], ms->pmsa_nat_bits, &old_regs->r11, &old_unat);
1032 	copy_reg(&ms->pmsa_gr[12-1], ms->pmsa_nat_bits, &old_regs->r12, &old_unat);
1033 	copy_reg(&ms->pmsa_gr[13-1], ms->pmsa_nat_bits, &old_regs->r13, &old_unat);
1034 	copy_reg(&ms->pmsa_gr[14-1], ms->pmsa_nat_bits, &old_regs->r14, &old_unat);
1035 	copy_reg(&ms->pmsa_gr[15-1], ms->pmsa_nat_bits, &old_regs->r15, &old_unat);
1036 	if (ia64_psr(old_regs)->bn)
1037 		bank = ms->pmsa_bank1_gr;
1038 	else
1039 		bank = ms->pmsa_bank0_gr;
1040 	copy_reg(&bank[16-16], ms->pmsa_nat_bits, &old_regs->r16, &old_unat);
1041 	copy_reg(&bank[17-16], ms->pmsa_nat_bits, &old_regs->r17, &old_unat);
1042 	copy_reg(&bank[18-16], ms->pmsa_nat_bits, &old_regs->r18, &old_unat);
1043 	copy_reg(&bank[19-16], ms->pmsa_nat_bits, &old_regs->r19, &old_unat);
1044 	copy_reg(&bank[20-16], ms->pmsa_nat_bits, &old_regs->r20, &old_unat);
1045 	copy_reg(&bank[21-16], ms->pmsa_nat_bits, &old_regs->r21, &old_unat);
1046 	copy_reg(&bank[22-16], ms->pmsa_nat_bits, &old_regs->r22, &old_unat);
1047 	copy_reg(&bank[23-16], ms->pmsa_nat_bits, &old_regs->r23, &old_unat);
1048 	copy_reg(&bank[24-16], ms->pmsa_nat_bits, &old_regs->r24, &old_unat);
1049 	copy_reg(&bank[25-16], ms->pmsa_nat_bits, &old_regs->r25, &old_unat);
1050 	copy_reg(&bank[26-16], ms->pmsa_nat_bits, &old_regs->r26, &old_unat);
1051 	copy_reg(&bank[27-16], ms->pmsa_nat_bits, &old_regs->r27, &old_unat);
1052 	copy_reg(&bank[28-16], ms->pmsa_nat_bits, &old_regs->r28, &old_unat);
1053 	copy_reg(&bank[29-16], ms->pmsa_nat_bits, &old_regs->r29, &old_unat);
1054 	copy_reg(&bank[30-16], ms->pmsa_nat_bits, &old_regs->r30, &old_unat);
1055 	copy_reg(&bank[31-16], ms->pmsa_nat_bits, &old_regs->r31, &old_unat);
1056 
1057 	/* Next stack a struct switch_stack.  mca_asm.S built a partial
1058 	 * switch_stack, copy it and fill in the blanks using pt_regs and
1059 	 * minstate.
1060 	 *
1061 	 * In the synthesized switch_stack, b0 points to ia64_leave_kernel,
1062 	 * ar.pfs is set to 0.
1063 	 *
1064 	 * unwind.c::unw_unwind() does special processing for interrupt frames.
1065 	 * It checks if the PRED_NON_SYSCALL predicate is set, if the predicate
1066 	 * is clear then unw_unwind() does _not_ adjust bsp over pt_regs.  Not
1067 	 * that this is documented, of course.  Set PRED_NON_SYSCALL in the
1068 	 * switch_stack on the original stack so it will unwind correctly when
1069 	 * unwind.c reads pt_regs.
1070 	 *
1071 	 * thread.ksp is updated to point to the synthesized switch_stack.
1072 	 */
1073 	p -= sizeof(struct switch_stack);
1074 	old_sw = (struct switch_stack *)p;
1075 	memcpy(old_sw, sw, sizeof(*sw));
1076 	old_sw->caller_unat = old_unat;
1077 	old_sw->ar_fpsr = old_regs->ar_fpsr;
1078 	copy_reg(&ms->pmsa_gr[4-1], ms->pmsa_nat_bits, &old_sw->r4, &old_unat);
1079 	copy_reg(&ms->pmsa_gr[5-1], ms->pmsa_nat_bits, &old_sw->r5, &old_unat);
1080 	copy_reg(&ms->pmsa_gr[6-1], ms->pmsa_nat_bits, &old_sw->r6, &old_unat);
1081 	copy_reg(&ms->pmsa_gr[7-1], ms->pmsa_nat_bits, &old_sw->r7, &old_unat);
1082 	old_sw->b0 = (u64)ia64_leave_kernel;
1083 	old_sw->b1 = ms->pmsa_br1;
1084 	old_sw->ar_pfs = 0;
1085 	old_sw->ar_unat = old_unat;
1086 	old_sw->pr = old_regs->pr | (1UL << PRED_NON_SYSCALL);
1087 	previous_current->thread.ksp = (u64)p - 16;
1088 
1089 	/* Finally copy the original stack's registers back to its RBS.
1090 	 * Registers from ar.bspstore through ar.bsp at the time of the event
1091 	 * are in the current RBS, copy them back to the original stack.  The
1092 	 * copy must be done register by register because the original bspstore
1093 	 * and the current one have different alignments, so the saved RNAT
1094 	 * data occurs at different places.
1095 	 *
1096 	 * mca_asm does cover, so the old_bsp already includes all registers at
1097 	 * the time of MCA/INIT.  It also does flushrs, so all registers before
1098 	 * this function have been written to backing store on the MCA/INIT
1099 	 * stack.
1100 	 */
1101 	new_rnat = ia64_get_rnat(ia64_rse_rnat_addr(new_bspstore));
1102 	old_rnat = regs->ar_rnat;
1103 	while (slots--) {
1104 		if (ia64_rse_is_rnat_slot(new_bspstore)) {
1105 			new_rnat = ia64_get_rnat(new_bspstore++);
1106 		}
1107 		if (ia64_rse_is_rnat_slot(old_bspstore)) {
1108 			*old_bspstore++ = old_rnat;
1109 			old_rnat = 0;
1110 		}
1111 		nat = (new_rnat >> ia64_rse_slot_num(new_bspstore)) & 1UL;
1112 		old_rnat &= ~(1UL << ia64_rse_slot_num(old_bspstore));
1113 		old_rnat |= (nat << ia64_rse_slot_num(old_bspstore));
1114 		*old_bspstore++ = *new_bspstore++;
1115 	}
1116 	old_sw->ar_bspstore = (unsigned long)old_bspstore;
1117 	old_sw->ar_rnat = old_rnat;
1118 
1119 	sos->prev_task = previous_current;
1120 	return previous_current;
1121 
1122 no_mod:
1123 	printk(KERN_INFO "cpu %d, %s %s, original stack not modified\n",
1124 			smp_processor_id(), type, msg);
1125 	return previous_current;
1126 }
1127 
1128 /* The monarch/slave interaction is based on monarch_cpu and requires that all
1129  * slaves have entered rendezvous before the monarch leaves.  If any cpu has
1130  * not entered rendezvous yet then wait a bit.  The assumption is that any
1131  * slave that has not rendezvoused after a reasonable time is never going to do
1132  * so.  In this context, slave includes cpus that respond to the MCA rendezvous
1133  * interrupt, as well as cpus that receive the INIT slave event.
1134  */
1135 
1136 static void
1137 ia64_wait_for_slaves(int monarch, const char *type)
1138 {
1139 	int c, i , wait;
1140 
1141 	/*
1142 	 * wait 5 seconds total for slaves (arbitrary)
1143 	 */
1144 	for (i = 0; i < 5000; i++) {
1145 		wait = 0;
1146 		for_each_online_cpu(c) {
1147 			if (c == monarch)
1148 				continue;
1149 			if (ia64_mc_info.imi_rendez_checkin[c]
1150 					== IA64_MCA_RENDEZ_CHECKIN_NOTDONE) {
1151 				udelay(1000);		/* short wait */
1152 				wait = 1;
1153 				break;
1154 			}
1155 		}
1156 		if (!wait)
1157 			goto all_in;
1158 	}
1159 
1160 	/*
1161 	 * Maybe slave(s) dead. Print buffered messages immediately.
1162 	 */
1163 	ia64_mlogbuf_finish(0);
1164 	mprintk(KERN_INFO "OS %s slave did not rendezvous on cpu", type);
1165 	for_each_online_cpu(c) {
1166 		if (c == monarch)
1167 			continue;
1168 		if (ia64_mc_info.imi_rendez_checkin[c] == IA64_MCA_RENDEZ_CHECKIN_NOTDONE)
1169 			mprintk(" %d", c);
1170 	}
1171 	mprintk("\n");
1172 	return;
1173 
1174 all_in:
1175 	mprintk(KERN_INFO "All OS %s slaves have reached rendezvous\n", type);
1176 	return;
1177 }
1178 
1179 /*
1180  * ia64_mca_handler
1181  *
1182  *	This is uncorrectable machine check handler called from OS_MCA
1183  *	dispatch code which is in turn called from SAL_CHECK().
1184  *	This is the place where the core of OS MCA handling is done.
1185  *	Right now the logs are extracted and displayed in a well-defined
1186  *	format. This handler code is supposed to be run only on the
1187  *	monarch processor. Once the monarch is done with MCA handling
1188  *	further MCA logging is enabled by clearing logs.
1189  *	Monarch also has the duty of sending wakeup-IPIs to pull the
1190  *	slave processors out of rendezvous spinloop.
1191  *
1192  *	If multiple processors call into OS_MCA, the first will become
1193  *	the monarch.  Subsequent cpus will be recorded in the mca_cpu
1194  *	bitmask.  After the first monarch has processed its MCA, it
1195  *	will wake up the next cpu in the mca_cpu bitmask and then go
1196  *	into the rendezvous loop.  When all processors have serviced
1197  *	their MCA, the last monarch frees up the rest of the processors.
1198  */
1199 void
1200 ia64_mca_handler(struct pt_regs *regs, struct switch_stack *sw,
1201 		 struct ia64_sal_os_state *sos)
1202 {
1203 	int recover, cpu = smp_processor_id();
1204 	struct task_struct *previous_current;
1205 	struct ia64_mca_notify_die nd =
1206 		{ .sos = sos, .monarch_cpu = &monarch_cpu };
1207 	static atomic_t mca_count;
1208 	static cpumask_t mca_cpu;
1209 
1210 	if (atomic_add_return(1, &mca_count) == 1) {
1211 		monarch_cpu = cpu;
1212 		sos->monarch = 1;
1213 	} else {
1214 		cpu_set(cpu, mca_cpu);
1215 		sos->monarch = 0;
1216 	}
1217 	mprintk(KERN_INFO "Entered OS MCA handler. PSP=%lx cpu=%d "
1218 		"monarch=%ld\n", sos->proc_state_param, cpu, sos->monarch);
1219 
1220 	previous_current = ia64_mca_modify_original_stack(regs, sw, sos, "MCA");
1221 
1222 	if (notify_die(DIE_MCA_MONARCH_ENTER, "MCA", regs, (long)&nd, 0, 0)
1223 			== NOTIFY_STOP)
1224 		ia64_mca_spin(__FUNCTION__);
1225 
1226 	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_CONCURRENT_MCA;
1227 	if (sos->monarch) {
1228 		ia64_wait_for_slaves(cpu, "MCA");
1229 
1230 		/* Wakeup all the processors which are spinning in the
1231 		 * rendezvous loop.  They will leave SAL, then spin in the OS
1232 		 * with interrupts disabled until this monarch cpu leaves the
1233 		 * MCA handler.  That gets control back to the OS so we can
1234 		 * backtrace the other cpus, backtrace when spinning in SAL
1235 		 * does not work.
1236 		 */
1237 		ia64_mca_wakeup_all();
1238 		if (notify_die(DIE_MCA_MONARCH_PROCESS, "MCA", regs, (long)&nd, 0, 0)
1239 				== NOTIFY_STOP)
1240 			ia64_mca_spin(__FUNCTION__);
1241 	} else {
1242 		while (cpu_isset(cpu, mca_cpu))
1243 			cpu_relax();	/* spin until monarch wakes us */
1244         }
1245 
1246 	/* Get the MCA error record and log it */
1247 	ia64_mca_log_sal_error_record(SAL_INFO_TYPE_MCA);
1248 
1249 	/* MCA error recovery */
1250 	recover = (ia64_mca_ucmc_extension
1251 		&& ia64_mca_ucmc_extension(
1252 			IA64_LOG_CURR_BUFFER(SAL_INFO_TYPE_MCA),
1253 			sos));
1254 
1255 	if (recover) {
1256 		sal_log_record_header_t *rh = IA64_LOG_CURR_BUFFER(SAL_INFO_TYPE_MCA);
1257 		rh->severity = sal_log_severity_corrected;
1258 		ia64_sal_clear_state_info(SAL_INFO_TYPE_MCA);
1259 		sos->os_status = IA64_MCA_CORRECTED;
1260 	} else {
1261 		/* Dump buffered message to console */
1262 		ia64_mlogbuf_finish(1);
1263 #ifdef CONFIG_KEXEC
1264 		atomic_set(&kdump_in_progress, 1);
1265 		monarch_cpu = -1;
1266 #endif
1267 	}
1268 	if (notify_die(DIE_MCA_MONARCH_LEAVE, "MCA", regs, (long)&nd, 0, recover)
1269 			== NOTIFY_STOP)
1270 		ia64_mca_spin(__FUNCTION__);
1271 
1272 
1273 	if (atomic_dec_return(&mca_count) > 0) {
1274 		int i;
1275 
1276 		/* wake up the next monarch cpu,
1277 		 * and put this cpu in the rendez loop.
1278 		 */
1279 		for_each_online_cpu(i) {
1280 			if (cpu_isset(i, mca_cpu)) {
1281 				monarch_cpu = i;
1282 				cpu_clear(i, mca_cpu);	/* wake next cpu */
1283 				while (monarch_cpu != -1)
1284 					cpu_relax();	/* spin until last cpu leaves */
1285 				set_curr_task(cpu, previous_current);
1286 				ia64_mc_info.imi_rendez_checkin[cpu]
1287 						= IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
1288 				return;
1289 			}
1290 		}
1291 	}
1292 	set_curr_task(cpu, previous_current);
1293 	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
1294 	monarch_cpu = -1;	/* This frees the slaves and previous monarchs */
1295 }
1296 
1297 static DECLARE_WORK(cmc_disable_work, ia64_mca_cmc_vector_disable_keventd);
1298 static DECLARE_WORK(cmc_enable_work, ia64_mca_cmc_vector_enable_keventd);
1299 
1300 /*
1301  * ia64_mca_cmc_int_handler
1302  *
1303  *  This is corrected machine check interrupt handler.
1304  *	Right now the logs are extracted and displayed in a well-defined
1305  *	format.
1306  *
1307  * Inputs
1308  *      interrupt number
1309  *      client data arg ptr
1310  *
1311  * Outputs
1312  *	None
1313  */
1314 static irqreturn_t
1315 ia64_mca_cmc_int_handler(int cmc_irq, void *arg)
1316 {
1317 	static unsigned long	cmc_history[CMC_HISTORY_LENGTH];
1318 	static int		index;
1319 	static DEFINE_SPINLOCK(cmc_history_lock);
1320 
1321 	IA64_MCA_DEBUG("%s: received interrupt vector = %#x on CPU %d\n",
1322 		       __FUNCTION__, cmc_irq, smp_processor_id());
1323 
1324 	/* SAL spec states this should run w/ interrupts enabled */
1325 	local_irq_enable();
1326 
1327 	spin_lock(&cmc_history_lock);
1328 	if (!cmc_polling_enabled) {
1329 		int i, count = 1; /* we know 1 happened now */
1330 		unsigned long now = jiffies;
1331 
1332 		for (i = 0; i < CMC_HISTORY_LENGTH; i++) {
1333 			if (now - cmc_history[i] <= HZ)
1334 				count++;
1335 		}
1336 
1337 		IA64_MCA_DEBUG(KERN_INFO "CMC threshold %d/%d\n", count, CMC_HISTORY_LENGTH);
1338 		if (count >= CMC_HISTORY_LENGTH) {
1339 
1340 			cmc_polling_enabled = 1;
1341 			spin_unlock(&cmc_history_lock);
1342 			/* If we're being hit with CMC interrupts, we won't
1343 			 * ever execute the schedule_work() below.  Need to
1344 			 * disable CMC interrupts on this processor now.
1345 			 */
1346 			ia64_mca_cmc_vector_disable(NULL);
1347 			schedule_work(&cmc_disable_work);
1348 
1349 			/*
1350 			 * Corrected errors will still be corrected, but
1351 			 * make sure there's a log somewhere that indicates
1352 			 * something is generating more than we can handle.
1353 			 */
1354 			printk(KERN_WARNING "WARNING: Switching to polling CMC handler; error records may be lost\n");
1355 
1356 			mod_timer(&cmc_poll_timer, jiffies + CMC_POLL_INTERVAL);
1357 
1358 			/* lock already released, get out now */
1359 			goto out;
1360 		} else {
1361 			cmc_history[index++] = now;
1362 			if (index == CMC_HISTORY_LENGTH)
1363 				index = 0;
1364 		}
1365 	}
1366 	spin_unlock(&cmc_history_lock);
1367 out:
1368 	/* Get the CMC error record and log it */
1369 	ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CMC);
1370 
1371 	return IRQ_HANDLED;
1372 }
1373 
1374 /*
1375  *  ia64_mca_cmc_int_caller
1376  *
1377  * 	Triggered by sw interrupt from CMC polling routine.  Calls
1378  * 	real interrupt handler and either triggers a sw interrupt
1379  * 	on the next cpu or does cleanup at the end.
1380  *
1381  * Inputs
1382  *	interrupt number
1383  *	client data arg ptr
1384  * Outputs
1385  * 	handled
1386  */
1387 static irqreturn_t
1388 ia64_mca_cmc_int_caller(int cmc_irq, void *arg)
1389 {
1390 	static int start_count = -1;
1391 	unsigned int cpuid;
1392 
1393 	cpuid = smp_processor_id();
1394 
1395 	/* If first cpu, update count */
1396 	if (start_count == -1)
1397 		start_count = IA64_LOG_COUNT(SAL_INFO_TYPE_CMC);
1398 
1399 	ia64_mca_cmc_int_handler(cmc_irq, arg);
1400 
1401 	for (++cpuid ; cpuid < NR_CPUS && !cpu_online(cpuid) ; cpuid++);
1402 
1403 	if (cpuid < NR_CPUS) {
1404 		platform_send_ipi(cpuid, IA64_CMCP_VECTOR, IA64_IPI_DM_INT, 0);
1405 	} else {
1406 		/* If no log record, switch out of polling mode */
1407 		if (start_count == IA64_LOG_COUNT(SAL_INFO_TYPE_CMC)) {
1408 
1409 			printk(KERN_WARNING "Returning to interrupt driven CMC handler\n");
1410 			schedule_work(&cmc_enable_work);
1411 			cmc_polling_enabled = 0;
1412 
1413 		} else {
1414 
1415 			mod_timer(&cmc_poll_timer, jiffies + CMC_POLL_INTERVAL);
1416 		}
1417 
1418 		start_count = -1;
1419 	}
1420 
1421 	return IRQ_HANDLED;
1422 }
1423 
1424 /*
1425  *  ia64_mca_cmc_poll
1426  *
1427  *	Poll for Corrected Machine Checks (CMCs)
1428  *
1429  * Inputs   :   dummy(unused)
1430  * Outputs  :   None
1431  *
1432  */
1433 static void
1434 ia64_mca_cmc_poll (unsigned long dummy)
1435 {
1436 	/* Trigger a CMC interrupt cascade  */
1437 	platform_send_ipi(first_cpu(cpu_online_map), IA64_CMCP_VECTOR, IA64_IPI_DM_INT, 0);
1438 }
1439 
1440 /*
1441  *  ia64_mca_cpe_int_caller
1442  *
1443  * 	Triggered by sw interrupt from CPE polling routine.  Calls
1444  * 	real interrupt handler and either triggers a sw interrupt
1445  * 	on the next cpu or does cleanup at the end.
1446  *
1447  * Inputs
1448  *	interrupt number
1449  *	client data arg ptr
1450  * Outputs
1451  * 	handled
1452  */
1453 #ifdef CONFIG_ACPI
1454 
1455 static irqreturn_t
1456 ia64_mca_cpe_int_caller(int cpe_irq, void *arg)
1457 {
1458 	static int start_count = -1;
1459 	static int poll_time = MIN_CPE_POLL_INTERVAL;
1460 	unsigned int cpuid;
1461 
1462 	cpuid = smp_processor_id();
1463 
1464 	/* If first cpu, update count */
1465 	if (start_count == -1)
1466 		start_count = IA64_LOG_COUNT(SAL_INFO_TYPE_CPE);
1467 
1468 	ia64_mca_cpe_int_handler(cpe_irq, arg);
1469 
1470 	for (++cpuid ; cpuid < NR_CPUS && !cpu_online(cpuid) ; cpuid++);
1471 
1472 	if (cpuid < NR_CPUS) {
1473 		platform_send_ipi(cpuid, IA64_CPEP_VECTOR, IA64_IPI_DM_INT, 0);
1474 	} else {
1475 		/*
1476 		 * If a log was recorded, increase our polling frequency,
1477 		 * otherwise, backoff or return to interrupt mode.
1478 		 */
1479 		if (start_count != IA64_LOG_COUNT(SAL_INFO_TYPE_CPE)) {
1480 			poll_time = max(MIN_CPE_POLL_INTERVAL, poll_time / 2);
1481 		} else if (cpe_vector < 0) {
1482 			poll_time = min(MAX_CPE_POLL_INTERVAL, poll_time * 2);
1483 		} else {
1484 			poll_time = MIN_CPE_POLL_INTERVAL;
1485 
1486 			printk(KERN_WARNING "Returning to interrupt driven CPE handler\n");
1487 			enable_irq(local_vector_to_irq(IA64_CPE_VECTOR));
1488 			cpe_poll_enabled = 0;
1489 		}
1490 
1491 		if (cpe_poll_enabled)
1492 			mod_timer(&cpe_poll_timer, jiffies + poll_time);
1493 		start_count = -1;
1494 	}
1495 
1496 	return IRQ_HANDLED;
1497 }
1498 
1499 /*
1500  *  ia64_mca_cpe_poll
1501  *
1502  *	Poll for Corrected Platform Errors (CPEs), trigger interrupt
1503  *	on first cpu, from there it will trickle through all the cpus.
1504  *
1505  * Inputs   :   dummy(unused)
1506  * Outputs  :   None
1507  *
1508  */
1509 static void
1510 ia64_mca_cpe_poll (unsigned long dummy)
1511 {
1512 	/* Trigger a CPE interrupt cascade  */
1513 	platform_send_ipi(first_cpu(cpu_online_map), IA64_CPEP_VECTOR, IA64_IPI_DM_INT, 0);
1514 }
1515 
1516 #endif /* CONFIG_ACPI */
1517 
1518 static int
1519 default_monarch_init_process(struct notifier_block *self, unsigned long val, void *data)
1520 {
1521 	int c;
1522 	struct task_struct *g, *t;
1523 	if (val != DIE_INIT_MONARCH_PROCESS)
1524 		return NOTIFY_DONE;
1525 #ifdef CONFIG_KEXEC
1526 	if (atomic_read(&kdump_in_progress))
1527 		return NOTIFY_DONE;
1528 #endif
1529 
1530 	/*
1531 	 * FIXME: mlogbuf will brim over with INIT stack dumps.
1532 	 * To enable show_stack from INIT, we use oops_in_progress which should
1533 	 * be used in real oops. This would cause something wrong after INIT.
1534 	 */
1535 	BREAK_LOGLEVEL(console_loglevel);
1536 	ia64_mlogbuf_dump_from_init();
1537 
1538 	printk(KERN_ERR "Processes interrupted by INIT -");
1539 	for_each_online_cpu(c) {
1540 		struct ia64_sal_os_state *s;
1541 		t = __va(__per_cpu_mca[c] + IA64_MCA_CPU_INIT_STACK_OFFSET);
1542 		s = (struct ia64_sal_os_state *)((char *)t + MCA_SOS_OFFSET);
1543 		g = s->prev_task;
1544 		if (g) {
1545 			if (g->pid)
1546 				printk(" %d", g->pid);
1547 			else
1548 				printk(" %d (cpu %d task 0x%p)", g->pid, task_cpu(g), g);
1549 		}
1550 	}
1551 	printk("\n\n");
1552 	if (read_trylock(&tasklist_lock)) {
1553 		do_each_thread (g, t) {
1554 			printk("\nBacktrace of pid %d (%s)\n", t->pid, t->comm);
1555 			show_stack(t, NULL);
1556 		} while_each_thread (g, t);
1557 		read_unlock(&tasklist_lock);
1558 	}
1559 	/* FIXME: This will not restore zapped printk locks. */
1560 	RESTORE_LOGLEVEL(console_loglevel);
1561 	return NOTIFY_DONE;
1562 }
1563 
1564 /*
1565  * C portion of the OS INIT handler
1566  *
1567  * Called from ia64_os_init_dispatch
1568  *
1569  * Inputs: pointer to pt_regs where processor info was saved.  SAL/OS state for
1570  * this event.  This code is used for both monarch and slave INIT events, see
1571  * sos->monarch.
1572  *
1573  * All INIT events switch to the INIT stack and change the previous process to
1574  * blocked status.  If one of the INIT events is the monarch then we are
1575  * probably processing the nmi button/command.  Use the monarch cpu to dump all
1576  * the processes.  The slave INIT events all spin until the monarch cpu
1577  * returns.  We can also get INIT slave events for MCA, in which case the MCA
1578  * process is the monarch.
1579  */
1580 
1581 void
1582 ia64_init_handler(struct pt_regs *regs, struct switch_stack *sw,
1583 		  struct ia64_sal_os_state *sos)
1584 {
1585 	static atomic_t slaves;
1586 	static atomic_t monarchs;
1587 	struct task_struct *previous_current;
1588 	int cpu = smp_processor_id();
1589 	struct ia64_mca_notify_die nd =
1590 		{ .sos = sos, .monarch_cpu = &monarch_cpu };
1591 
1592 	(void) notify_die(DIE_INIT_ENTER, "INIT", regs, (long)&nd, 0, 0);
1593 
1594 	mprintk(KERN_INFO "Entered OS INIT handler. PSP=%lx cpu=%d monarch=%ld\n",
1595 		sos->proc_state_param, cpu, sos->monarch);
1596 	salinfo_log_wakeup(SAL_INFO_TYPE_INIT, NULL, 0, 0);
1597 
1598 	previous_current = ia64_mca_modify_original_stack(regs, sw, sos, "INIT");
1599 	sos->os_status = IA64_INIT_RESUME;
1600 
1601 	/* FIXME: Workaround for broken proms that drive all INIT events as
1602 	 * slaves.  The last slave that enters is promoted to be a monarch.
1603 	 * Remove this code in September 2006, that gives platforms a year to
1604 	 * fix their proms and get their customers updated.
1605 	 */
1606 	if (!sos->monarch && atomic_add_return(1, &slaves) == num_online_cpus()) {
1607 		mprintk(KERN_WARNING "%s: Promoting cpu %d to monarch.\n",
1608 		       __FUNCTION__, cpu);
1609 		atomic_dec(&slaves);
1610 		sos->monarch = 1;
1611 	}
1612 
1613 	/* FIXME: Workaround for broken proms that drive all INIT events as
1614 	 * monarchs.  Second and subsequent monarchs are demoted to slaves.
1615 	 * Remove this code in September 2006, that gives platforms a year to
1616 	 * fix their proms and get their customers updated.
1617 	 */
1618 	if (sos->monarch && atomic_add_return(1, &monarchs) > 1) {
1619 		mprintk(KERN_WARNING "%s: Demoting cpu %d to slave.\n",
1620 			       __FUNCTION__, cpu);
1621 		atomic_dec(&monarchs);
1622 		sos->monarch = 0;
1623 	}
1624 
1625 	if (!sos->monarch) {
1626 		ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_INIT;
1627 		while (monarch_cpu == -1)
1628 		       cpu_relax();	/* spin until monarch enters */
1629 		if (notify_die(DIE_INIT_SLAVE_ENTER, "INIT", regs, (long)&nd, 0, 0)
1630 				== NOTIFY_STOP)
1631 			ia64_mca_spin(__FUNCTION__);
1632 		if (notify_die(DIE_INIT_SLAVE_PROCESS, "INIT", regs, (long)&nd, 0, 0)
1633 				== NOTIFY_STOP)
1634 			ia64_mca_spin(__FUNCTION__);
1635 		while (monarch_cpu != -1)
1636 		       cpu_relax();	/* spin until monarch leaves */
1637 		if (notify_die(DIE_INIT_SLAVE_LEAVE, "INIT", regs, (long)&nd, 0, 0)
1638 				== NOTIFY_STOP)
1639 			ia64_mca_spin(__FUNCTION__);
1640 		mprintk("Slave on cpu %d returning to normal service.\n", cpu);
1641 		set_curr_task(cpu, previous_current);
1642 		ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
1643 		atomic_dec(&slaves);
1644 		return;
1645 	}
1646 
1647 	monarch_cpu = cpu;
1648 	if (notify_die(DIE_INIT_MONARCH_ENTER, "INIT", regs, (long)&nd, 0, 0)
1649 			== NOTIFY_STOP)
1650 		ia64_mca_spin(__FUNCTION__);
1651 
1652 	/*
1653 	 * Wait for a bit.  On some machines (e.g., HP's zx2000 and zx6000, INIT can be
1654 	 * generated via the BMC's command-line interface, but since the console is on the
1655 	 * same serial line, the user will need some time to switch out of the BMC before
1656 	 * the dump begins.
1657 	 */
1658 	mprintk("Delaying for 5 seconds...\n");
1659 	udelay(5*1000000);
1660 	ia64_wait_for_slaves(cpu, "INIT");
1661 	/* If nobody intercepts DIE_INIT_MONARCH_PROCESS then we drop through
1662 	 * to default_monarch_init_process() above and just print all the
1663 	 * tasks.
1664 	 */
1665 	if (notify_die(DIE_INIT_MONARCH_PROCESS, "INIT", regs, (long)&nd, 0, 0)
1666 			== NOTIFY_STOP)
1667 		ia64_mca_spin(__FUNCTION__);
1668 	if (notify_die(DIE_INIT_MONARCH_LEAVE, "INIT", regs, (long)&nd, 0, 0)
1669 			== NOTIFY_STOP)
1670 		ia64_mca_spin(__FUNCTION__);
1671 	mprintk("\nINIT dump complete.  Monarch on cpu %d returning to normal service.\n", cpu);
1672 	atomic_dec(&monarchs);
1673 	set_curr_task(cpu, previous_current);
1674 	monarch_cpu = -1;
1675 	return;
1676 }
1677 
1678 static int __init
1679 ia64_mca_disable_cpe_polling(char *str)
1680 {
1681 	cpe_poll_enabled = 0;
1682 	return 1;
1683 }
1684 
1685 __setup("disable_cpe_poll", ia64_mca_disable_cpe_polling);
1686 
1687 static struct irqaction cmci_irqaction = {
1688 	.handler =	ia64_mca_cmc_int_handler,
1689 	.flags =	IRQF_DISABLED,
1690 	.name =		"cmc_hndlr"
1691 };
1692 
1693 static struct irqaction cmcp_irqaction = {
1694 	.handler =	ia64_mca_cmc_int_caller,
1695 	.flags =	IRQF_DISABLED,
1696 	.name =		"cmc_poll"
1697 };
1698 
1699 static struct irqaction mca_rdzv_irqaction = {
1700 	.handler =	ia64_mca_rendez_int_handler,
1701 	.flags =	IRQF_DISABLED,
1702 	.name =		"mca_rdzv"
1703 };
1704 
1705 static struct irqaction mca_wkup_irqaction = {
1706 	.handler =	ia64_mca_wakeup_int_handler,
1707 	.flags =	IRQF_DISABLED,
1708 	.name =		"mca_wkup"
1709 };
1710 
1711 #ifdef CONFIG_ACPI
1712 static struct irqaction mca_cpe_irqaction = {
1713 	.handler =	ia64_mca_cpe_int_handler,
1714 	.flags =	IRQF_DISABLED,
1715 	.name =		"cpe_hndlr"
1716 };
1717 
1718 static struct irqaction mca_cpep_irqaction = {
1719 	.handler =	ia64_mca_cpe_int_caller,
1720 	.flags =	IRQF_DISABLED,
1721 	.name =		"cpe_poll"
1722 };
1723 #endif /* CONFIG_ACPI */
1724 
1725 /* Minimal format of the MCA/INIT stacks.  The pseudo processes that run on
1726  * these stacks can never sleep, they cannot return from the kernel to user
1727  * space, they do not appear in a normal ps listing.  So there is no need to
1728  * format most of the fields.
1729  */
1730 
1731 static void __cpuinit
1732 format_mca_init_stack(void *mca_data, unsigned long offset,
1733 		const char *type, int cpu)
1734 {
1735 	struct task_struct *p = (struct task_struct *)((char *)mca_data + offset);
1736 	struct thread_info *ti;
1737 	memset(p, 0, KERNEL_STACK_SIZE);
1738 	ti = task_thread_info(p);
1739 	ti->flags = _TIF_MCA_INIT;
1740 	ti->preempt_count = 1;
1741 	ti->task = p;
1742 	ti->cpu = cpu;
1743 	p->stack = ti;
1744 	p->state = TASK_UNINTERRUPTIBLE;
1745 	cpu_set(cpu, p->cpus_allowed);
1746 	INIT_LIST_HEAD(&p->tasks);
1747 	p->parent = p->real_parent = p->group_leader = p;
1748 	INIT_LIST_HEAD(&p->children);
1749 	INIT_LIST_HEAD(&p->sibling);
1750 	strncpy(p->comm, type, sizeof(p->comm)-1);
1751 }
1752 
1753 /* Caller prevents this from being called after init */
1754 static void * __init_refok mca_bootmem(void)
1755 {
1756 	void *p;
1757 
1758 	p = alloc_bootmem(sizeof(struct ia64_mca_cpu) * NR_CPUS +
1759 	                  KERNEL_STACK_SIZE);
1760 	return (void *)ALIGN((unsigned long)p, KERNEL_STACK_SIZE);
1761 }
1762 
1763 /* Do per-CPU MCA-related initialization.  */
1764 void __cpuinit
1765 ia64_mca_cpu_init(void *cpu_data)
1766 {
1767 	void *pal_vaddr;
1768 	static int first_time = 1;
1769 
1770 	if (first_time) {
1771 		void *mca_data;
1772 		int cpu;
1773 
1774 		first_time = 0;
1775 		mca_data = mca_bootmem();
1776 		for (cpu = 0; cpu < NR_CPUS; cpu++) {
1777 			format_mca_init_stack(mca_data,
1778 					offsetof(struct ia64_mca_cpu, mca_stack),
1779 					"MCA", cpu);
1780 			format_mca_init_stack(mca_data,
1781 					offsetof(struct ia64_mca_cpu, init_stack),
1782 					"INIT", cpu);
1783 			__per_cpu_mca[cpu] = __pa(mca_data);
1784 			mca_data += sizeof(struct ia64_mca_cpu);
1785 		}
1786 	}
1787 
1788 	/*
1789 	 * The MCA info structure was allocated earlier and its
1790 	 * physical address saved in __per_cpu_mca[cpu].  Copy that
1791 	 * address * to ia64_mca_data so we can access it as a per-CPU
1792 	 * variable.
1793 	 */
1794 	__get_cpu_var(ia64_mca_data) = __per_cpu_mca[smp_processor_id()];
1795 
1796 	/*
1797 	 * Stash away a copy of the PTE needed to map the per-CPU page.
1798 	 * We may need it during MCA recovery.
1799 	 */
1800 	__get_cpu_var(ia64_mca_per_cpu_pte) =
1801 		pte_val(mk_pte_phys(__pa(cpu_data), PAGE_KERNEL));
1802 
1803 	/*
1804 	 * Also, stash away a copy of the PAL address and the PTE
1805 	 * needed to map it.
1806 	 */
1807 	pal_vaddr = efi_get_pal_addr();
1808 	if (!pal_vaddr)
1809 		return;
1810 	__get_cpu_var(ia64_mca_pal_base) =
1811 		GRANULEROUNDDOWN((unsigned long) pal_vaddr);
1812 	__get_cpu_var(ia64_mca_pal_pte) = pte_val(mk_pte_phys(__pa(pal_vaddr),
1813 							      PAGE_KERNEL));
1814 }
1815 
1816 /*
1817  * ia64_mca_init
1818  *
1819  *  Do all the system level mca specific initialization.
1820  *
1821  *	1. Register spinloop and wakeup request interrupt vectors
1822  *
1823  *	2. Register OS_MCA handler entry point
1824  *
1825  *	3. Register OS_INIT handler entry point
1826  *
1827  *  4. Initialize MCA/CMC/INIT related log buffers maintained by the OS.
1828  *
1829  *  Note that this initialization is done very early before some kernel
1830  *  services are available.
1831  *
1832  *  Inputs  :   None
1833  *
1834  *  Outputs :   None
1835  */
1836 void __init
1837 ia64_mca_init(void)
1838 {
1839 	ia64_fptr_t *init_hldlr_ptr_monarch = (ia64_fptr_t *)ia64_os_init_dispatch_monarch;
1840 	ia64_fptr_t *init_hldlr_ptr_slave = (ia64_fptr_t *)ia64_os_init_dispatch_slave;
1841 	ia64_fptr_t *mca_hldlr_ptr = (ia64_fptr_t *)ia64_os_mca_dispatch;
1842 	int i;
1843 	s64 rc;
1844 	struct ia64_sal_retval isrv;
1845 	u64 timeout = IA64_MCA_RENDEZ_TIMEOUT;	/* platform specific */
1846 	static struct notifier_block default_init_monarch_nb = {
1847 		.notifier_call = default_monarch_init_process,
1848 		.priority = 0/* we need to notified last */
1849 	};
1850 
1851 	IA64_MCA_DEBUG("%s: begin\n", __FUNCTION__);
1852 
1853 	/* Clear the Rendez checkin flag for all cpus */
1854 	for(i = 0 ; i < NR_CPUS; i++)
1855 		ia64_mc_info.imi_rendez_checkin[i] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
1856 
1857 	/*
1858 	 * Register the rendezvous spinloop and wakeup mechanism with SAL
1859 	 */
1860 
1861 	/* Register the rendezvous interrupt vector with SAL */
1862 	while (1) {
1863 		isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_RENDEZ_INT,
1864 					      SAL_MC_PARAM_MECHANISM_INT,
1865 					      IA64_MCA_RENDEZ_VECTOR,
1866 					      timeout,
1867 					      SAL_MC_PARAM_RZ_ALWAYS);
1868 		rc = isrv.status;
1869 		if (rc == 0)
1870 			break;
1871 		if (rc == -2) {
1872 			printk(KERN_INFO "Increasing MCA rendezvous timeout from "
1873 				"%ld to %ld milliseconds\n", timeout, isrv.v0);
1874 			timeout = isrv.v0;
1875 			(void) notify_die(DIE_MCA_NEW_TIMEOUT, "MCA", NULL, timeout, 0, 0);
1876 			continue;
1877 		}
1878 		printk(KERN_ERR "Failed to register rendezvous interrupt "
1879 		       "with SAL (status %ld)\n", rc);
1880 		return;
1881 	}
1882 
1883 	/* Register the wakeup interrupt vector with SAL */
1884 	isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_RENDEZ_WAKEUP,
1885 				      SAL_MC_PARAM_MECHANISM_INT,
1886 				      IA64_MCA_WAKEUP_VECTOR,
1887 				      0, 0);
1888 	rc = isrv.status;
1889 	if (rc) {
1890 		printk(KERN_ERR "Failed to register wakeup interrupt with SAL "
1891 		       "(status %ld)\n", rc);
1892 		return;
1893 	}
1894 
1895 	IA64_MCA_DEBUG("%s: registered MCA rendezvous spinloop and wakeup mech.\n", __FUNCTION__);
1896 
1897 	ia64_mc_info.imi_mca_handler        = ia64_tpa(mca_hldlr_ptr->fp);
1898 	/*
1899 	 * XXX - disable SAL checksum by setting size to 0; should be
1900 	 *	ia64_tpa(ia64_os_mca_dispatch_end) - ia64_tpa(ia64_os_mca_dispatch);
1901 	 */
1902 	ia64_mc_info.imi_mca_handler_size	= 0;
1903 
1904 	/* Register the os mca handler with SAL */
1905 	if ((rc = ia64_sal_set_vectors(SAL_VECTOR_OS_MCA,
1906 				       ia64_mc_info.imi_mca_handler,
1907 				       ia64_tpa(mca_hldlr_ptr->gp),
1908 				       ia64_mc_info.imi_mca_handler_size,
1909 				       0, 0, 0)))
1910 	{
1911 		printk(KERN_ERR "Failed to register OS MCA handler with SAL "
1912 		       "(status %ld)\n", rc);
1913 		return;
1914 	}
1915 
1916 	IA64_MCA_DEBUG("%s: registered OS MCA handler with SAL at 0x%lx, gp = 0x%lx\n", __FUNCTION__,
1917 		       ia64_mc_info.imi_mca_handler, ia64_tpa(mca_hldlr_ptr->gp));
1918 
1919 	/*
1920 	 * XXX - disable SAL checksum by setting size to 0, should be
1921 	 * size of the actual init handler in mca_asm.S.
1922 	 */
1923 	ia64_mc_info.imi_monarch_init_handler		= ia64_tpa(init_hldlr_ptr_monarch->fp);
1924 	ia64_mc_info.imi_monarch_init_handler_size	= 0;
1925 	ia64_mc_info.imi_slave_init_handler		= ia64_tpa(init_hldlr_ptr_slave->fp);
1926 	ia64_mc_info.imi_slave_init_handler_size	= 0;
1927 
1928 	IA64_MCA_DEBUG("%s: OS INIT handler at %lx\n", __FUNCTION__,
1929 		       ia64_mc_info.imi_monarch_init_handler);
1930 
1931 	/* Register the os init handler with SAL */
1932 	if ((rc = ia64_sal_set_vectors(SAL_VECTOR_OS_INIT,
1933 				       ia64_mc_info.imi_monarch_init_handler,
1934 				       ia64_tpa(ia64_getreg(_IA64_REG_GP)),
1935 				       ia64_mc_info.imi_monarch_init_handler_size,
1936 				       ia64_mc_info.imi_slave_init_handler,
1937 				       ia64_tpa(ia64_getreg(_IA64_REG_GP)),
1938 				       ia64_mc_info.imi_slave_init_handler_size)))
1939 	{
1940 		printk(KERN_ERR "Failed to register m/s INIT handlers with SAL "
1941 		       "(status %ld)\n", rc);
1942 		return;
1943 	}
1944 	if (register_die_notifier(&default_init_monarch_nb)) {
1945 		printk(KERN_ERR "Failed to register default monarch INIT process\n");
1946 		return;
1947 	}
1948 
1949 	IA64_MCA_DEBUG("%s: registered OS INIT handler with SAL\n", __FUNCTION__);
1950 
1951 	/*
1952 	 *  Configure the CMCI/P vector and handler. Interrupts for CMC are
1953 	 *  per-processor, so AP CMC interrupts are setup in smp_callin() (smpboot.c).
1954 	 */
1955 	register_percpu_irq(IA64_CMC_VECTOR, &cmci_irqaction);
1956 	register_percpu_irq(IA64_CMCP_VECTOR, &cmcp_irqaction);
1957 	ia64_mca_cmc_vector_setup();       /* Setup vector on BSP */
1958 
1959 	/* Setup the MCA rendezvous interrupt vector */
1960 	register_percpu_irq(IA64_MCA_RENDEZ_VECTOR, &mca_rdzv_irqaction);
1961 
1962 	/* Setup the MCA wakeup interrupt vector */
1963 	register_percpu_irq(IA64_MCA_WAKEUP_VECTOR, &mca_wkup_irqaction);
1964 
1965 #ifdef CONFIG_ACPI
1966 	/* Setup the CPEI/P handler */
1967 	register_percpu_irq(IA64_CPEP_VECTOR, &mca_cpep_irqaction);
1968 #endif
1969 
1970 	/* Initialize the areas set aside by the OS to buffer the
1971 	 * platform/processor error states for MCA/INIT/CMC
1972 	 * handling.
1973 	 */
1974 	ia64_log_init(SAL_INFO_TYPE_MCA);
1975 	ia64_log_init(SAL_INFO_TYPE_INIT);
1976 	ia64_log_init(SAL_INFO_TYPE_CMC);
1977 	ia64_log_init(SAL_INFO_TYPE_CPE);
1978 
1979 	mca_init = 1;
1980 	printk(KERN_INFO "MCA related initialization done\n");
1981 }
1982 
1983 /*
1984  * ia64_mca_late_init
1985  *
1986  *	Opportunity to setup things that require initialization later
1987  *	than ia64_mca_init.  Setup a timer to poll for CPEs if the
1988  *	platform doesn't support an interrupt driven mechanism.
1989  *
1990  *  Inputs  :   None
1991  *  Outputs :   Status
1992  */
1993 static int __init
1994 ia64_mca_late_init(void)
1995 {
1996 	if (!mca_init)
1997 		return 0;
1998 
1999 	/* Setup the CMCI/P vector and handler */
2000 	init_timer(&cmc_poll_timer);
2001 	cmc_poll_timer.function = ia64_mca_cmc_poll;
2002 
2003 	/* Unmask/enable the vector */
2004 	cmc_polling_enabled = 0;
2005 	schedule_work(&cmc_enable_work);
2006 
2007 	IA64_MCA_DEBUG("%s: CMCI/P setup and enabled.\n", __FUNCTION__);
2008 
2009 #ifdef CONFIG_ACPI
2010 	/* Setup the CPEI/P vector and handler */
2011 	cpe_vector = acpi_request_vector(ACPI_INTERRUPT_CPEI);
2012 	init_timer(&cpe_poll_timer);
2013 	cpe_poll_timer.function = ia64_mca_cpe_poll;
2014 
2015 	{
2016 		irq_desc_t *desc;
2017 		unsigned int irq;
2018 
2019 		if (cpe_vector >= 0) {
2020 			/* If platform supports CPEI, enable the irq. */
2021 			irq = local_vector_to_irq(cpe_vector);
2022 			if (irq > 0) {
2023 				cpe_poll_enabled = 0;
2024 				desc = irq_desc + irq;
2025 				desc->status |= IRQ_PER_CPU;
2026 				setup_irq(irq, &mca_cpe_irqaction);
2027 				ia64_cpe_irq = irq;
2028 				ia64_mca_register_cpev(cpe_vector);
2029 				IA64_MCA_DEBUG("%s: CPEI/P setup and enabled.\n",
2030 					__FUNCTION__);
2031 				return 0;
2032 			}
2033 			printk(KERN_ERR "%s: Failed to find irq for CPE "
2034 					"interrupt handler, vector %d\n",
2035 					__FUNCTION__, cpe_vector);
2036 		}
2037 		/* If platform doesn't support CPEI, get the timer going. */
2038 		if (cpe_poll_enabled) {
2039 			ia64_mca_cpe_poll(0UL);
2040 			IA64_MCA_DEBUG("%s: CPEP setup and enabled.\n", __FUNCTION__);
2041 		}
2042 	}
2043 #endif
2044 
2045 	return 0;
2046 }
2047 
2048 device_initcall(ia64_mca_late_init);
2049