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32 results

xfrm_input.c

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  • mca.c 59.13 KiB
    /*
     * File:	mca.c
     * Purpose:	Generic MCA handling layer
     *
     * Updated for latest kernel
     * Copyright (C) 2003 Hewlett-Packard Co
     *	David Mosberger-Tang <davidm@hpl.hp.com>
     *
     * Copyright (C) 2002 Dell Inc.
     * Copyright (C) Matt Domsch (Matt_Domsch@dell.com)
     *
     * Copyright (C) 2002 Intel
     * Copyright (C) Jenna Hall (jenna.s.hall@intel.com)
     *
     * Copyright (C) 2001 Intel
     * Copyright (C) Fred Lewis (frederick.v.lewis@intel.com)
     *
     * Copyright (C) 2000 Intel
     * Copyright (C) Chuck Fleckenstein (cfleck@co.intel.com)
     *
     * Copyright (C) 1999, 2004 Silicon Graphics, Inc.
     * Copyright (C) Vijay Chander(vijay@engr.sgi.com)
     *
     * 03/04/15 D. Mosberger Added INIT backtrace support.
     * 02/03/25 M. Domsch	GUID cleanups
     *
     * 02/01/04 J. Hall	Aligned MCA stack to 16 bytes, added platform vs. CPU
     *			error flag, set SAL default return values, changed
     *			error record structure to linked list, added init call
     *			to sal_get_state_info_size().
     *
     * 01/01/03 F. Lewis    Added setup of CMCI and CPEI IRQs, logging of corrected
     *                      platform errors, completed code for logging of
     *                      corrected & uncorrected machine check errors, and
     *                      updated for conformance with Nov. 2000 revision of the
     *                      SAL 3.0 spec.
     * 00/03/29 C. Fleckenstein  Fixed PAL/SAL update issues, began MCA bug fixes, logging issues,
     *                           added min save state dump, added INIT handler.
     *
     * 2003-12-08 Keith Owens <kaos@sgi.com>
     *            smp_call_function() must not be called from interrupt context (can
     *            deadlock on tasklist_lock).  Use keventd to call smp_call_function().
     *
     * 2004-02-01 Keith Owens <kaos@sgi.com>
     *            Avoid deadlock when using printk() for MCA and INIT records.
     *            Delete all record printing code, moved to salinfo_decode in user space.
     *            Mark variables and functions static where possible.
     *            Delete dead variables and functions.
     *            Reorder to remove the need for forward declarations and to consolidate
     *            related code.
     *
     * 2005-08-12 Keith Owens <kaos@sgi.com>
     *	      Convert MCA/INIT handlers to use per event stacks and SAL/OS state.
     *
     * 2005-10-07 Keith Owens <kaos@sgi.com>
     *	      Add notify_die() hooks.
     *
     * 2006-09-15 Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
     * 	      Add printing support for MCA/INIT.
     *
     * 2007-04-27 Russ Anderson <rja@sgi.com>
     *	      Support multiple cpus going through OS_MCA in the same event.
     */
    #include <linux/types.h>
    #include <linux/init.h>
    #include <linux/sched.h>
    #include <linux/interrupt.h>
    #include <linux/irq.h>
    #include <linux/bootmem.h>
    #include <linux/acpi.h>
    #include <linux/timer.h>
    #include <linux/module.h>
    #include <linux/kernel.h>
    #include <linux/smp.h>
    #include <linux/workqueue.h>
    #include <linux/cpumask.h>
    #include <linux/kdebug.h>
    
    #include <asm/delay.h>
    #include <asm/machvec.h>
    #include <asm/meminit.h>
    #include <asm/page.h>
    #include <asm/ptrace.h>
    #include <asm/system.h>
    #include <asm/sal.h>
    #include <asm/mca.h>
    #include <asm/kexec.h>
    
    #include <asm/irq.h>
    #include <asm/hw_irq.h>
    
    #include "mca_drv.h"
    #include "entry.h"
    
    #if defined(IA64_MCA_DEBUG_INFO)
    # define IA64_MCA_DEBUG(fmt...)	printk(fmt)
    #else
    # define IA64_MCA_DEBUG(fmt...)
    #endif
    
    /* Used by mca_asm.S */
    DEFINE_PER_CPU(u64, ia64_mca_data); /* == __per_cpu_mca[smp_processor_id()] */
    DEFINE_PER_CPU(u64, ia64_mca_per_cpu_pte); /* PTE to map per-CPU area */
    DEFINE_PER_CPU(u64, ia64_mca_pal_pte);	    /* PTE to map PAL code */
    DEFINE_PER_CPU(u64, ia64_mca_pal_base);    /* vaddr PAL code granule */
    
    unsigned long __per_cpu_mca[NR_CPUS];
    
    /* In mca_asm.S */
    extern void			ia64_os_init_dispatch_monarch (void);
    extern void			ia64_os_init_dispatch_slave (void);
    
    static int monarch_cpu = -1;
    
    static ia64_mc_info_t		ia64_mc_info;
    
    #define MAX_CPE_POLL_INTERVAL (15*60*HZ) /* 15 minutes */
    #define MIN_CPE_POLL_INTERVAL (2*60*HZ)  /* 2 minutes */
    #define CMC_POLL_INTERVAL     (1*60*HZ)  /* 1 minute */
    #define CPE_HISTORY_LENGTH    5
    #define CMC_HISTORY_LENGTH    5
    
    #ifdef CONFIG_ACPI
    static struct timer_list cpe_poll_timer;
    #endif
    static struct timer_list cmc_poll_timer;
    /*
     * This variable tells whether we are currently in polling mode.
     * Start with this in the wrong state so we won't play w/ timers
     * before the system is ready.
     */
    static int cmc_polling_enabled = 1;
    
    /*
     * Clearing this variable prevents CPE polling from getting activated
     * in mca_late_init.  Use it if your system doesn't provide a CPEI,
     * but encounters problems retrieving CPE logs.  This should only be
     * necessary for debugging.
     */
    static int cpe_poll_enabled = 1;
    
    extern void salinfo_log_wakeup(int type, u8 *buffer, u64 size, int irqsafe);
    
    static int mca_init __initdata;
    
    /*
     * limited & delayed printing support for MCA/INIT handler
     */
    
    #define mprintk(fmt...) ia64_mca_printk(fmt)
    
    #define MLOGBUF_SIZE (512+256*NR_CPUS)
    #define MLOGBUF_MSGMAX 256
    static char mlogbuf[MLOGBUF_SIZE];
    static DEFINE_SPINLOCK(mlogbuf_wlock);	/* mca context only */
    static DEFINE_SPINLOCK(mlogbuf_rlock);	/* normal context only */
    static unsigned long mlogbuf_start;
    static unsigned long mlogbuf_end;
    static unsigned int mlogbuf_finished = 0;
    static unsigned long mlogbuf_timestamp = 0;
    
    static int loglevel_save = -1;
    #define BREAK_LOGLEVEL(__console_loglevel)		\
    	oops_in_progress = 1;				\
    	if (loglevel_save < 0)				\
    		loglevel_save = __console_loglevel;	\
    	__console_loglevel = 15;
    
    #define RESTORE_LOGLEVEL(__console_loglevel)		\
    	if (loglevel_save >= 0) {			\
    		__console_loglevel = loglevel_save;	\
    		loglevel_save = -1;			\
    	}						\
    	mlogbuf_finished = 0;				\
    	oops_in_progress = 0;
    
    /*
     * Push messages into buffer, print them later if not urgent.
     */
    void ia64_mca_printk(const char *fmt, ...)
    {
    	va_list args;
    	int printed_len;
    	char temp_buf[MLOGBUF_MSGMAX];
    	char *p;
    
    	va_start(args, fmt);
    	printed_len = vscnprintf(temp_buf, sizeof(temp_buf), fmt, args);
    	va_end(args);
    
    	/* Copy the output into mlogbuf */
    	if (oops_in_progress) {
    		/* mlogbuf was abandoned, use printk directly instead. */
    		printk(temp_buf);
    	} else {
    		spin_lock(&mlogbuf_wlock);
    		for (p = temp_buf; *p; p++) {
    			unsigned long next = (mlogbuf_end + 1) % MLOGBUF_SIZE;
    			if (next != mlogbuf_start) {
    				mlogbuf[mlogbuf_end] = *p;
    				mlogbuf_end = next;
    			} else {
    				/* buffer full */
    				break;
    			}
    		}
    		mlogbuf[mlogbuf_end] = '\0';
    		spin_unlock(&mlogbuf_wlock);
    	}
    }
    EXPORT_SYMBOL(ia64_mca_printk);
    
    /*
     * Print buffered messages.
     *  NOTE: call this after returning normal context. (ex. from salinfod)
     */
    void ia64_mlogbuf_dump(void)
    {
    	char temp_buf[MLOGBUF_MSGMAX];
    	char *p;
    	unsigned long index;
    	unsigned long flags;
    	unsigned int printed_len;
    
    	/* Get output from mlogbuf */
    	while (mlogbuf_start != mlogbuf_end) {
    		temp_buf[0] = '\0';
    		p = temp_buf;
    		printed_len = 0;
    
    		spin_lock_irqsave(&mlogbuf_rlock, flags);
    
    		index = mlogbuf_start;
    		while (index != mlogbuf_end) {
    			*p = mlogbuf[index];
    			index = (index + 1) % MLOGBUF_SIZE;
    			if (!*p)
    				break;
    			p++;
    			if (++printed_len >= MLOGBUF_MSGMAX - 1)
    				break;
    		}
    		*p = '\0';
    		if (temp_buf[0])
    			printk(temp_buf);
    		mlogbuf_start = index;
    
    		mlogbuf_timestamp = 0;
    		spin_unlock_irqrestore(&mlogbuf_rlock, flags);
    	}
    }
    EXPORT_SYMBOL(ia64_mlogbuf_dump);
    
    /*
     * Call this if system is going to down or if immediate flushing messages to
     * console is required. (ex. recovery was failed, crash dump is going to be
     * invoked, long-wait rendezvous etc.)
     *  NOTE: this should be called from monarch.
     */
    static void ia64_mlogbuf_finish(int wait)
    {
    	BREAK_LOGLEVEL(console_loglevel);
    
    	spin_lock_init(&mlogbuf_rlock);
    	ia64_mlogbuf_dump();
    	printk(KERN_EMERG "mlogbuf_finish: printing switched to urgent mode, "
    		"MCA/INIT might be dodgy or fail.\n");
    
    	if (!wait)
    		return;
    
    	/* wait for console */
    	printk("Delaying for 5 seconds...\n");
    	udelay(5*1000000);
    
    	mlogbuf_finished = 1;
    }
    
    /*
     * Print buffered messages from INIT context.
     */
    static void ia64_mlogbuf_dump_from_init(void)
    {
    	if (mlogbuf_finished)
    		return;
    
    	if (mlogbuf_timestamp && (mlogbuf_timestamp + 30*HZ > jiffies)) {
    		printk(KERN_ERR "INIT: mlogbuf_dump is interrupted by INIT "
    			" and the system seems to be messed up.\n");
    		ia64_mlogbuf_finish(0);
    		return;
    	}
    
    	if (!spin_trylock(&mlogbuf_rlock)) {
    		printk(KERN_ERR "INIT: mlogbuf_dump is interrupted by INIT. "
    			"Generated messages other than stack dump will be "
    			"buffered to mlogbuf and will be printed later.\n");
    		printk(KERN_ERR "INIT: If messages would not printed after "
    			"this INIT, wait 30sec and assert INIT again.\n");
    		if (!mlogbuf_timestamp)
    			mlogbuf_timestamp = jiffies;
    		return;
    	}
    	spin_unlock(&mlogbuf_rlock);
    	ia64_mlogbuf_dump();
    }
    
    static void inline
    ia64_mca_spin(const char *func)
    {
    	if (monarch_cpu == smp_processor_id())
    		ia64_mlogbuf_finish(0);
    	mprintk(KERN_EMERG "%s: spinning here, not returning to SAL\n", func);
    	while (1)
    		cpu_relax();
    }
    /*
     * IA64_MCA log support
     */
    #define IA64_MAX_LOGS		2	/* Double-buffering for nested MCAs */
    #define IA64_MAX_LOG_TYPES      4   /* MCA, INIT, CMC, CPE */
    
    typedef struct ia64_state_log_s
    {
    	spinlock_t	isl_lock;
    	int		isl_index;
    	unsigned long	isl_count;
    	ia64_err_rec_t  *isl_log[IA64_MAX_LOGS]; /* need space to store header + error log */
    } ia64_state_log_t;
    
    static ia64_state_log_t ia64_state_log[IA64_MAX_LOG_TYPES];
    
    #define IA64_LOG_ALLOCATE(it, size) \
    	{ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)] = \
    		(ia64_err_rec_t *)alloc_bootmem(size); \
    	ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)] = \
    		(ia64_err_rec_t *)alloc_bootmem(size);}
    #define IA64_LOG_LOCK_INIT(it) spin_lock_init(&ia64_state_log[it].isl_lock)
    #define IA64_LOG_LOCK(it)      spin_lock_irqsave(&ia64_state_log[it].isl_lock, s)
    #define IA64_LOG_UNLOCK(it)    spin_unlock_irqrestore(&ia64_state_log[it].isl_lock,s)
    #define IA64_LOG_NEXT_INDEX(it)    ia64_state_log[it].isl_index
    #define IA64_LOG_CURR_INDEX(it)    1 - ia64_state_log[it].isl_index
    #define IA64_LOG_INDEX_INC(it) \
        {ia64_state_log[it].isl_index = 1 - ia64_state_log[it].isl_index; \
        ia64_state_log[it].isl_count++;}
    #define IA64_LOG_INDEX_DEC(it) \
        ia64_state_log[it].isl_index = 1 - ia64_state_log[it].isl_index
    #define IA64_LOG_NEXT_BUFFER(it)   (void *)((ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)]))
    #define IA64_LOG_CURR_BUFFER(it)   (void *)((ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)]))
    #define IA64_LOG_COUNT(it)         ia64_state_log[it].isl_count
    
    /*
     * ia64_log_init
     *	Reset the OS ia64 log buffer
     * Inputs   :   info_type   (SAL_INFO_TYPE_{MCA,INIT,CMC,CPE})
     * Outputs	:	None
     */
    static void __init
    ia64_log_init(int sal_info_type)
    {
    	u64	max_size = 0;
    
    	IA64_LOG_NEXT_INDEX(sal_info_type) = 0;
    	IA64_LOG_LOCK_INIT(sal_info_type);
    
    	// SAL will tell us the maximum size of any error record of this type
    	max_size = ia64_sal_get_state_info_size(sal_info_type);
    	if (!max_size)
    		/* alloc_bootmem() doesn't like zero-sized allocations! */
    		return;
    
    	// set up OS data structures to hold error info
    	IA64_LOG_ALLOCATE(sal_info_type, max_size);
    	memset(IA64_LOG_CURR_BUFFER(sal_info_type), 0, max_size);
    	memset(IA64_LOG_NEXT_BUFFER(sal_info_type), 0, max_size);
    }
    
    /*
     * ia64_log_get
     *
     *	Get the current MCA log from SAL and copy it into the OS log buffer.
     *
     *  Inputs  :   info_type   (SAL_INFO_TYPE_{MCA,INIT,CMC,CPE})
     *              irq_safe    whether you can use printk at this point
     *  Outputs :   size        (total record length)
     *              *buffer     (ptr to error record)
     *
     */
    static u64
    ia64_log_get(int sal_info_type, u8 **buffer, int irq_safe)
    {
    	sal_log_record_header_t     *log_buffer;
    	u64                         total_len = 0;
    	unsigned long               s;
    
    	IA64_LOG_LOCK(sal_info_type);
    
    	/* Get the process state information */
    	log_buffer = IA64_LOG_NEXT_BUFFER(sal_info_type);
    
    	total_len = ia64_sal_get_state_info(sal_info_type, (u64 *)log_buffer);
    
    	if (total_len) {
    		IA64_LOG_INDEX_INC(sal_info_type);
    		IA64_LOG_UNLOCK(sal_info_type);
    		if (irq_safe) {
    			IA64_MCA_DEBUG("%s: SAL error record type %d retrieved. "
    				       "Record length = %ld\n", __FUNCTION__, sal_info_type, total_len);
    		}
    		*buffer = (u8 *) log_buffer;
    		return total_len;
    	} else {
    		IA64_LOG_UNLOCK(sal_info_type);
    		return 0;
    	}
    }
    
    /*
     *  ia64_mca_log_sal_error_record
     *
     *  This function retrieves a specified error record type from SAL
     *  and wakes up any processes waiting for error records.
     *
     *  Inputs  :   sal_info_type   (Type of error record MCA/CMC/CPE)
     *              FIXME: remove MCA and irq_safe.
     */
    static void
    ia64_mca_log_sal_error_record(int sal_info_type)
    {
    	u8 *buffer;
    	sal_log_record_header_t *rh;
    	u64 size;
    	int irq_safe = sal_info_type != SAL_INFO_TYPE_MCA;
    #ifdef IA64_MCA_DEBUG_INFO
    	static const char * const rec_name[] = { "MCA", "INIT", "CMC", "CPE" };
    #endif
    
    	size = ia64_log_get(sal_info_type, &buffer, irq_safe);
    	if (!size)
    		return;
    
    	salinfo_log_wakeup(sal_info_type, buffer, size, irq_safe);
    
    	if (irq_safe)
    		IA64_MCA_DEBUG("CPU %d: SAL log contains %s error record\n",
    			smp_processor_id(),
    			sal_info_type < ARRAY_SIZE(rec_name) ? rec_name[sal_info_type] : "UNKNOWN");
    
    	/* Clear logs from corrected errors in case there's no user-level logger */
    	rh = (sal_log_record_header_t *)buffer;
    	if (rh->severity == sal_log_severity_corrected)
    		ia64_sal_clear_state_info(sal_info_type);
    }
    
    /*
     * search_mca_table
     *  See if the MCA surfaced in an instruction range
     *  that has been tagged as recoverable.
     *
     *  Inputs
     *	first	First address range to check
     *	last	Last address range to check
     *	ip	Instruction pointer, address we are looking for
     *
     * Return value:
     *      1 on Success (in the table)/ 0 on Failure (not in the  table)
     */
    int
    search_mca_table (const struct mca_table_entry *first,
                    const struct mca_table_entry *last,
                    unsigned long ip)
    {
            const struct mca_table_entry *curr;
            u64 curr_start, curr_end;
    
            curr = first;
            while (curr <= last) {
                    curr_start = (u64) &curr->start_addr + curr->start_addr;
                    curr_end = (u64) &curr->end_addr + curr->end_addr;
    
                    if ((ip >= curr_start) && (ip <= curr_end)) {
                            return 1;
                    }
                    curr++;
            }
            return 0;
    }
    
    /* Given an address, look for it in the mca tables. */
    int mca_recover_range(unsigned long addr)
    {
    	extern struct mca_table_entry __start___mca_table[];
    	extern struct mca_table_entry __stop___mca_table[];
    
    	return search_mca_table(__start___mca_table, __stop___mca_table-1, addr);
    }
    EXPORT_SYMBOL_GPL(mca_recover_range);
    
    #ifdef CONFIG_ACPI
    
    int cpe_vector = -1;
    int ia64_cpe_irq = -1;
    
    static irqreturn_t
    ia64_mca_cpe_int_handler (int cpe_irq, void *arg)
    {
    	static unsigned long	cpe_history[CPE_HISTORY_LENGTH];
    	static int		index;
    	static DEFINE_SPINLOCK(cpe_history_lock);
    
    	IA64_MCA_DEBUG("%s: received interrupt vector = %#x on CPU %d\n",
    		       __FUNCTION__, cpe_irq, smp_processor_id());
    
    	/* SAL spec states this should run w/ interrupts enabled */
    	local_irq_enable();
    
    	spin_lock(&cpe_history_lock);
    	if (!cpe_poll_enabled && cpe_vector >= 0) {
    
    		int i, count = 1; /* we know 1 happened now */
    		unsigned long now = jiffies;
    
    		for (i = 0; i < CPE_HISTORY_LENGTH; i++) {
    			if (now - cpe_history[i] <= HZ)
    				count++;
    		}
    
    		IA64_MCA_DEBUG(KERN_INFO "CPE threshold %d/%d\n", count, CPE_HISTORY_LENGTH);
    		if (count >= CPE_HISTORY_LENGTH) {
    
    			cpe_poll_enabled = 1;
    			spin_unlock(&cpe_history_lock);
    			disable_irq_nosync(local_vector_to_irq(IA64_CPE_VECTOR));
    
    			/*
    			 * Corrected errors will still be corrected, but
    			 * make sure there's a log somewhere that indicates
    			 * something is generating more than we can handle.
    			 */
    			printk(KERN_WARNING "WARNING: Switching to polling CPE handler; error records may be lost\n");
    
    			mod_timer(&cpe_poll_timer, jiffies + MIN_CPE_POLL_INTERVAL);
    
    			/* lock already released, get out now */
    			goto out;
    		} else {
    			cpe_history[index++] = now;
    			if (index == CPE_HISTORY_LENGTH)
    				index = 0;
    		}
    	}
    	spin_unlock(&cpe_history_lock);
    out:
    	/* Get the CPE error record and log it */
    	ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CPE);
    
    	return IRQ_HANDLED;
    }
    
    #endif /* CONFIG_ACPI */
    
    #ifdef CONFIG_ACPI
    /*
     * ia64_mca_register_cpev
     *
     *  Register the corrected platform error vector with SAL.
     *
     *  Inputs
     *      cpev        Corrected Platform Error Vector number
     *
     *  Outputs
     *      None
     */
    void
    ia64_mca_register_cpev (int cpev)
    {
    	/* Register the CPE interrupt vector with SAL */
    	struct ia64_sal_retval isrv;
    
    	isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_CPE_INT, SAL_MC_PARAM_MECHANISM_INT, cpev, 0, 0);
    	if (isrv.status) {
    		printk(KERN_ERR "Failed to register Corrected Platform "
    		       "Error interrupt vector with SAL (status %ld)\n", isrv.status);
    		return;
    	}
    
    	IA64_MCA_DEBUG("%s: corrected platform error "
    		       "vector %#x registered\n", __FUNCTION__, cpev);
    }
    #endif /* CONFIG_ACPI */
    
    /*
     * ia64_mca_cmc_vector_setup
     *
     *  Setup the corrected machine check vector register in the processor.
     *  (The interrupt is masked on boot. ia64_mca_late_init unmask this.)
     *  This function is invoked on a per-processor basis.
     *
     * Inputs
     *      None
     *
     * Outputs
     *	None
     */
    void __cpuinit
    ia64_mca_cmc_vector_setup (void)
    {
    	cmcv_reg_t	cmcv;
    
    	cmcv.cmcv_regval	= 0;
    	cmcv.cmcv_mask		= 1;        /* Mask/disable interrupt at first */
    	cmcv.cmcv_vector	= IA64_CMC_VECTOR;
    	ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
    
    	IA64_MCA_DEBUG("%s: CPU %d corrected "
    		       "machine check vector %#x registered.\n",
    		       __FUNCTION__, smp_processor_id(), IA64_CMC_VECTOR);
    
    	IA64_MCA_DEBUG("%s: CPU %d CMCV = %#016lx\n",
    		       __FUNCTION__, smp_processor_id(), ia64_getreg(_IA64_REG_CR_CMCV));
    }
    
    /*
     * ia64_mca_cmc_vector_disable
     *
     *  Mask the corrected machine check vector register in the processor.
     *  This function is invoked on a per-processor basis.
     *
     * Inputs
     *      dummy(unused)
     *
     * Outputs
     *	None
     */
    static void
    ia64_mca_cmc_vector_disable (void *dummy)
    {
    	cmcv_reg_t	cmcv;
    
    	cmcv.cmcv_regval = ia64_getreg(_IA64_REG_CR_CMCV);
    
    	cmcv.cmcv_mask = 1; /* Mask/disable interrupt */
    	ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
    
    	IA64_MCA_DEBUG("%s: CPU %d corrected "
    		       "machine check vector %#x disabled.\n",
    		       __FUNCTION__, smp_processor_id(), cmcv.cmcv_vector);
    }
    
    /*
     * ia64_mca_cmc_vector_enable
     *
     *  Unmask the corrected machine check vector register in the processor.
     *  This function is invoked on a per-processor basis.
     *
     * Inputs
     *      dummy(unused)
     *
     * Outputs
     *	None
     */
    static void
    ia64_mca_cmc_vector_enable (void *dummy)
    {
    	cmcv_reg_t	cmcv;
    
    	cmcv.cmcv_regval = ia64_getreg(_IA64_REG_CR_CMCV);
    
    	cmcv.cmcv_mask = 0; /* Unmask/enable interrupt */
    	ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
    
    	IA64_MCA_DEBUG("%s: CPU %d corrected "
    		       "machine check vector %#x enabled.\n",
    		       __FUNCTION__, smp_processor_id(), cmcv.cmcv_vector);
    }
    
    /*
     * ia64_mca_cmc_vector_disable_keventd
     *
     * Called via keventd (smp_call_function() is not safe in interrupt context) to
     * disable the cmc interrupt vector.
     */
    static void
    ia64_mca_cmc_vector_disable_keventd(struct work_struct *unused)
    {
    	on_each_cpu(ia64_mca_cmc_vector_disable, NULL, 1, 0);
    }
    
    /*
     * ia64_mca_cmc_vector_enable_keventd
     *
     * Called via keventd (smp_call_function() is not safe in interrupt context) to
     * enable the cmc interrupt vector.
     */
    static void
    ia64_mca_cmc_vector_enable_keventd(struct work_struct *unused)
    {
    	on_each_cpu(ia64_mca_cmc_vector_enable, NULL, 1, 0);
    }
    
    /*
     * ia64_mca_wakeup
     *
     *	Send an inter-cpu interrupt to wake-up a particular cpu.
     *
     *  Inputs  :   cpuid
     *  Outputs :   None
     */
    static void
    ia64_mca_wakeup(int cpu)
    {
    	platform_send_ipi(cpu, IA64_MCA_WAKEUP_VECTOR, IA64_IPI_DM_INT, 0);
    }
    
    /*
     * ia64_mca_wakeup_all
     *
     *	Wakeup all the slave cpus which have rendez'ed previously.
     *
     *  Inputs  :   None
     *  Outputs :   None
     */
    static void
    ia64_mca_wakeup_all(void)
    {
    	int cpu;
    
    	/* Clear the Rendez checkin flag for all cpus */
    	for_each_online_cpu(cpu) {
    		if (ia64_mc_info.imi_rendez_checkin[cpu] == IA64_MCA_RENDEZ_CHECKIN_DONE)
    			ia64_mca_wakeup(cpu);
    	}
    
    }
    
    /*
     * ia64_mca_rendez_interrupt_handler
     *
     *	This is handler used to put slave processors into spinloop
     *	while the monarch processor does the mca handling and later
     *	wake each slave up once the monarch is done.  The state
     *	IA64_MCA_RENDEZ_CHECKIN_DONE indicates the cpu is rendez'ed
     *	in SAL.  The state IA64_MCA_RENDEZ_CHECKIN_NOTDONE indicates
     *	the cpu has come out of OS rendezvous.
     *
     *  Inputs  :   None
     *  Outputs :   None
     */
    static irqreturn_t
    ia64_mca_rendez_int_handler(int rendez_irq, void *arg)
    {
    	unsigned long flags;
    	int cpu = smp_processor_id();
    	struct ia64_mca_notify_die nd =
    		{ .sos = NULL, .monarch_cpu = &monarch_cpu };
    
    	/* Mask all interrupts */
    	local_irq_save(flags);
    	if (notify_die(DIE_MCA_RENDZVOUS_ENTER, "MCA", get_irq_regs(),
    		       (long)&nd, 0, 0) == NOTIFY_STOP)
    		ia64_mca_spin(__FUNCTION__);
    
    	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_DONE;
    	/* Register with the SAL monarch that the slave has
    	 * reached SAL
    	 */
    	ia64_sal_mc_rendez();
    
    	if (notify_die(DIE_MCA_RENDZVOUS_PROCESS, "MCA", get_irq_regs(),
    		       (long)&nd, 0, 0) == NOTIFY_STOP)
    		ia64_mca_spin(__FUNCTION__);
    
    	/* Wait for the monarch cpu to exit. */
    	while (monarch_cpu != -1)
    	       cpu_relax();	/* spin until monarch leaves */
    
    	if (notify_die(DIE_MCA_RENDZVOUS_LEAVE, "MCA", get_irq_regs(),
    		       (long)&nd, 0, 0) == NOTIFY_STOP)
    		ia64_mca_spin(__FUNCTION__);
    
    	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
    	/* Enable all interrupts */
    	local_irq_restore(flags);
    	return IRQ_HANDLED;
    }
    
    /*
     * ia64_mca_wakeup_int_handler
     *
     *	The interrupt handler for processing the inter-cpu interrupt to the
     *	slave cpu which was spinning in the rendez loop.
     *	Since this spinning is done by turning off the interrupts and
     *	polling on the wakeup-interrupt bit in the IRR, there is
     *	nothing useful to be done in the handler.
     *
     *  Inputs  :   wakeup_irq  (Wakeup-interrupt bit)
     *	arg		(Interrupt handler specific argument)
     *  Outputs :   None
     *
     */
    static irqreturn_t
    ia64_mca_wakeup_int_handler(int wakeup_irq, void *arg)
    {
    	return IRQ_HANDLED;
    }
    
    /* Function pointer for extra MCA recovery */
    int (*ia64_mca_ucmc_extension)
    	(void*,struct ia64_sal_os_state*)
    	= NULL;
    
    int
    ia64_reg_MCA_extension(int (*fn)(void *, struct ia64_sal_os_state *))
    {
    	if (ia64_mca_ucmc_extension)
    		return 1;
    
    	ia64_mca_ucmc_extension = fn;
    	return 0;
    }
    
    void
    ia64_unreg_MCA_extension(void)
    {
    	if (ia64_mca_ucmc_extension)
    		ia64_mca_ucmc_extension = NULL;
    }
    
    EXPORT_SYMBOL(ia64_reg_MCA_extension);
    EXPORT_SYMBOL(ia64_unreg_MCA_extension);
    
    
    static inline void
    copy_reg(const u64 *fr, u64 fnat, u64 *tr, u64 *tnat)
    {
    	u64 fslot, tslot, nat;
    	*tr = *fr;
    	fslot = ((unsigned long)fr >> 3) & 63;
    	tslot = ((unsigned long)tr >> 3) & 63;
    	*tnat &= ~(1UL << tslot);
    	nat = (fnat >> fslot) & 1;
    	*tnat |= (nat << tslot);
    }
    
    /* Change the comm field on the MCA/INT task to include the pid that
     * was interrupted, it makes for easier debugging.  If that pid was 0
     * (swapper or nested MCA/INIT) then use the start of the previous comm
     * field suffixed with its cpu.
     */
    
    static void
    ia64_mca_modify_comm(const struct task_struct *previous_current)
    {
    	char *p, comm[sizeof(current->comm)];
    	if (previous_current->pid)
    		snprintf(comm, sizeof(comm), "%s %d",
    			current->comm, previous_current->pid);
    	else {
    		int l;
    		if ((p = strchr(previous_current->comm, ' ')))
    			l = p - previous_current->comm;
    		else
    			l = strlen(previous_current->comm);
    		snprintf(comm, sizeof(comm), "%s %*s %d",
    			current->comm, l, previous_current->comm,
    			task_thread_info(previous_current)->cpu);
    	}
    	memcpy(current->comm, comm, sizeof(current->comm));
    }
    
    /* On entry to this routine, we are running on the per cpu stack, see
     * mca_asm.h.  The original stack has not been touched by this event.  Some of
     * the original stack's registers will be in the RBS on this stack.  This stack
     * also contains a partial pt_regs and switch_stack, the rest of the data is in
     * PAL minstate.
     *
     * The first thing to do is modify the original stack to look like a blocked
     * task so we can run backtrace on the original task.  Also mark the per cpu
     * stack as current to ensure that we use the correct task state, it also means
     * that we can do backtrace on the MCA/INIT handler code itself.
     */
    
    static struct task_struct *
    ia64_mca_modify_original_stack(struct pt_regs *regs,
    		const struct switch_stack *sw,
    		struct ia64_sal_os_state *sos,
    		const char *type)
    {
    	char *p;
    	ia64_va va;
    	extern char ia64_leave_kernel[];	/* Need asm address, not function descriptor */
    	const pal_min_state_area_t *ms = sos->pal_min_state;
    	struct task_struct *previous_current;
    	struct pt_regs *old_regs;
    	struct switch_stack *old_sw;
    	unsigned size = sizeof(struct pt_regs) +
    			sizeof(struct switch_stack) + 16;
    	u64 *old_bspstore, *old_bsp;
    	u64 *new_bspstore, *new_bsp;
    	u64 old_unat, old_rnat, new_rnat, nat;
    	u64 slots, loadrs = regs->loadrs;
    	u64 r12 = ms->pmsa_gr[12-1], r13 = ms->pmsa_gr[13-1];
    	u64 ar_bspstore = regs->ar_bspstore;
    	u64 ar_bsp = regs->ar_bspstore + (loadrs >> 16);
    	const u64 *bank;
    	const char *msg;
    	int cpu = smp_processor_id();
    
    	previous_current = curr_task(cpu);
    	set_curr_task(cpu, current);
    	if ((p = strchr(current->comm, ' ')))
    		*p = '\0';
    
    	/* Best effort attempt to cope with MCA/INIT delivered while in
    	 * physical mode.
    	 */
    	regs->cr_ipsr = ms->pmsa_ipsr;
    	if (ia64_psr(regs)->dt == 0) {
    		va.l = r12;
    		if (va.f.reg == 0) {
    			va.f.reg = 7;
    			r12 = va.l;
    		}
    		va.l = r13;
    		if (va.f.reg == 0) {
    			va.f.reg = 7;
    			r13 = va.l;
    		}
    	}
    	if (ia64_psr(regs)->rt == 0) {
    		va.l = ar_bspstore;
    		if (va.f.reg == 0) {
    			va.f.reg = 7;
    			ar_bspstore = va.l;
    		}
    		va.l = ar_bsp;
    		if (va.f.reg == 0) {
    			va.f.reg = 7;
    			ar_bsp = va.l;
    		}
    	}
    
    	/* mca_asm.S ia64_old_stack() cannot assume that the dirty registers
    	 * have been copied to the old stack, the old stack may fail the
    	 * validation tests below.  So ia64_old_stack() must restore the dirty
    	 * registers from the new stack.  The old and new bspstore probably
    	 * have different alignments, so loadrs calculated on the old bsp
    	 * cannot be used to restore from the new bsp.  Calculate a suitable
    	 * loadrs for the new stack and save it in the new pt_regs, where
    	 * ia64_old_stack() can get it.
    	 */
    	old_bspstore = (u64 *)ar_bspstore;
    	old_bsp = (u64 *)ar_bsp;
    	slots = ia64_rse_num_regs(old_bspstore, old_bsp);
    	new_bspstore = (u64 *)((u64)current + IA64_RBS_OFFSET);
    	new_bsp = ia64_rse_skip_regs(new_bspstore, slots);
    	regs->loadrs = (new_bsp - new_bspstore) * 8 << 16;
    
    	/* Verify the previous stack state before we change it */
    	if (user_mode(regs)) {
    		msg = "occurred in user space";
    		/* previous_current is guaranteed to be valid when the task was
    		 * in user space, so ...
    		 */
    		ia64_mca_modify_comm(previous_current);
    		goto no_mod;
    	}
    
    	if (r13 != sos->prev_IA64_KR_CURRENT) {
    		msg = "inconsistent previous current and r13";
    		goto no_mod;
    	}
    
    	if (!mca_recover_range(ms->pmsa_iip)) {
    		if ((r12 - r13) >= KERNEL_STACK_SIZE) {
    			msg = "inconsistent r12 and r13";
    			goto no_mod;
    		}
    		if ((ar_bspstore - r13) >= KERNEL_STACK_SIZE) {
    			msg = "inconsistent ar.bspstore and r13";
    			goto no_mod;
    		}
    		va.p = old_bspstore;
    		if (va.f.reg < 5) {
    			msg = "old_bspstore is in the wrong region";
    			goto no_mod;
    		}
    		if ((ar_bsp - r13) >= KERNEL_STACK_SIZE) {
    			msg = "inconsistent ar.bsp and r13";
    			goto no_mod;
    		}
    		size += (ia64_rse_skip_regs(old_bspstore, slots) - old_bspstore) * 8;
    		if (ar_bspstore + size > r12) {
    			msg = "no room for blocked state";
    			goto no_mod;
    		}
    	}
    
    	ia64_mca_modify_comm(previous_current);
    
    	/* Make the original task look blocked.  First stack a struct pt_regs,
    	 * describing the state at the time of interrupt.  mca_asm.S built a
    	 * partial pt_regs, copy it and fill in the blanks using minstate.
    	 */
    	p = (char *)r12 - sizeof(*regs);
    	old_regs = (struct pt_regs *)p;
    	memcpy(old_regs, regs, sizeof(*regs));
    	/* If ipsr.ic then use pmsa_{iip,ipsr,ifs}, else use
    	 * pmsa_{xip,xpsr,xfs}
    	 */
    	if (ia64_psr(regs)->ic) {
    		old_regs->cr_iip = ms->pmsa_iip;
    		old_regs->cr_ipsr = ms->pmsa_ipsr;
    		old_regs->cr_ifs = ms->pmsa_ifs;
    	} else {
    		old_regs->cr_iip = ms->pmsa_xip;
    		old_regs->cr_ipsr = ms->pmsa_xpsr;
    		old_regs->cr_ifs = ms->pmsa_xfs;
    	}
    	old_regs->pr = ms->pmsa_pr;
    	old_regs->b0 = ms->pmsa_br0;
    	old_regs->loadrs = loadrs;
    	old_regs->ar_rsc = ms->pmsa_rsc;
    	old_unat = old_regs->ar_unat;
    	copy_reg(&ms->pmsa_gr[1-1], ms->pmsa_nat_bits, &old_regs->r1, &old_unat);
    	copy_reg(&ms->pmsa_gr[2-1], ms->pmsa_nat_bits, &old_regs->r2, &old_unat);
    	copy_reg(&ms->pmsa_gr[3-1], ms->pmsa_nat_bits, &old_regs->r3, &old_unat);
    	copy_reg(&ms->pmsa_gr[8-1], ms->pmsa_nat_bits, &old_regs->r8, &old_unat);
    	copy_reg(&ms->pmsa_gr[9-1], ms->pmsa_nat_bits, &old_regs->r9, &old_unat);
    	copy_reg(&ms->pmsa_gr[10-1], ms->pmsa_nat_bits, &old_regs->r10, &old_unat);
    	copy_reg(&ms->pmsa_gr[11-1], ms->pmsa_nat_bits, &old_regs->r11, &old_unat);
    	copy_reg(&ms->pmsa_gr[12-1], ms->pmsa_nat_bits, &old_regs->r12, &old_unat);
    	copy_reg(&ms->pmsa_gr[13-1], ms->pmsa_nat_bits, &old_regs->r13, &old_unat);
    	copy_reg(&ms->pmsa_gr[14-1], ms->pmsa_nat_bits, &old_regs->r14, &old_unat);
    	copy_reg(&ms->pmsa_gr[15-1], ms->pmsa_nat_bits, &old_regs->r15, &old_unat);
    	if (ia64_psr(old_regs)->bn)
    		bank = ms->pmsa_bank1_gr;
    	else
    		bank = ms->pmsa_bank0_gr;
    	copy_reg(&bank[16-16], ms->pmsa_nat_bits, &old_regs->r16, &old_unat);
    	copy_reg(&bank[17-16], ms->pmsa_nat_bits, &old_regs->r17, &old_unat);
    	copy_reg(&bank[18-16], ms->pmsa_nat_bits, &old_regs->r18, &old_unat);
    	copy_reg(&bank[19-16], ms->pmsa_nat_bits, &old_regs->r19, &old_unat);
    	copy_reg(&bank[20-16], ms->pmsa_nat_bits, &old_regs->r20, &old_unat);
    	copy_reg(&bank[21-16], ms->pmsa_nat_bits, &old_regs->r21, &old_unat);
    	copy_reg(&bank[22-16], ms->pmsa_nat_bits, &old_regs->r22, &old_unat);
    	copy_reg(&bank[23-16], ms->pmsa_nat_bits, &old_regs->r23, &old_unat);
    	copy_reg(&bank[24-16], ms->pmsa_nat_bits, &old_regs->r24, &old_unat);
    	copy_reg(&bank[25-16], ms->pmsa_nat_bits, &old_regs->r25, &old_unat);
    	copy_reg(&bank[26-16], ms->pmsa_nat_bits, &old_regs->r26, &old_unat);
    	copy_reg(&bank[27-16], ms->pmsa_nat_bits, &old_regs->r27, &old_unat);
    	copy_reg(&bank[28-16], ms->pmsa_nat_bits, &old_regs->r28, &old_unat);
    	copy_reg(&bank[29-16], ms->pmsa_nat_bits, &old_regs->r29, &old_unat);
    	copy_reg(&bank[30-16], ms->pmsa_nat_bits, &old_regs->r30, &old_unat);
    	copy_reg(&bank[31-16], ms->pmsa_nat_bits, &old_regs->r31, &old_unat);
    
    	/* Next stack a struct switch_stack.  mca_asm.S built a partial
    	 * switch_stack, copy it and fill in the blanks using pt_regs and
    	 * minstate.
    	 *
    	 * In the synthesized switch_stack, b0 points to ia64_leave_kernel,
    	 * ar.pfs is set to 0.
    	 *
    	 * unwind.c::unw_unwind() does special processing for interrupt frames.
    	 * It checks if the PRED_NON_SYSCALL predicate is set, if the predicate
    	 * is clear then unw_unwind() does _not_ adjust bsp over pt_regs.  Not
    	 * that this is documented, of course.  Set PRED_NON_SYSCALL in the
    	 * switch_stack on the original stack so it will unwind correctly when
    	 * unwind.c reads pt_regs.
    	 *
    	 * thread.ksp is updated to point to the synthesized switch_stack.
    	 */
    	p -= sizeof(struct switch_stack);
    	old_sw = (struct switch_stack *)p;
    	memcpy(old_sw, sw, sizeof(*sw));
    	old_sw->caller_unat = old_unat;
    	old_sw->ar_fpsr = old_regs->ar_fpsr;
    	copy_reg(&ms->pmsa_gr[4-1], ms->pmsa_nat_bits, &old_sw->r4, &old_unat);
    	copy_reg(&ms->pmsa_gr[5-1], ms->pmsa_nat_bits, &old_sw->r5, &old_unat);
    	copy_reg(&ms->pmsa_gr[6-1], ms->pmsa_nat_bits, &old_sw->r6, &old_unat);
    	copy_reg(&ms->pmsa_gr[7-1], ms->pmsa_nat_bits, &old_sw->r7, &old_unat);
    	old_sw->b0 = (u64)ia64_leave_kernel;
    	old_sw->b1 = ms->pmsa_br1;
    	old_sw->ar_pfs = 0;
    	old_sw->ar_unat = old_unat;
    	old_sw->pr = old_regs->pr | (1UL << PRED_NON_SYSCALL);
    	previous_current->thread.ksp = (u64)p - 16;
    
    	/* Finally copy the original stack's registers back to its RBS.
    	 * Registers from ar.bspstore through ar.bsp at the time of the event
    	 * are in the current RBS, copy them back to the original stack.  The
    	 * copy must be done register by register because the original bspstore
    	 * and the current one have different alignments, so the saved RNAT
    	 * data occurs at different places.
    	 *
    	 * mca_asm does cover, so the old_bsp already includes all registers at
    	 * the time of MCA/INIT.  It also does flushrs, so all registers before
    	 * this function have been written to backing store on the MCA/INIT
    	 * stack.
    	 */
    	new_rnat = ia64_get_rnat(ia64_rse_rnat_addr(new_bspstore));
    	old_rnat = regs->ar_rnat;
    	while (slots--) {
    		if (ia64_rse_is_rnat_slot(new_bspstore)) {
    			new_rnat = ia64_get_rnat(new_bspstore++);
    		}
    		if (ia64_rse_is_rnat_slot(old_bspstore)) {
    			*old_bspstore++ = old_rnat;
    			old_rnat = 0;
    		}
    		nat = (new_rnat >> ia64_rse_slot_num(new_bspstore)) & 1UL;
    		old_rnat &= ~(1UL << ia64_rse_slot_num(old_bspstore));
    		old_rnat |= (nat << ia64_rse_slot_num(old_bspstore));
    		*old_bspstore++ = *new_bspstore++;
    	}
    	old_sw->ar_bspstore = (unsigned long)old_bspstore;
    	old_sw->ar_rnat = old_rnat;
    
    	sos->prev_task = previous_current;
    	return previous_current;
    
    no_mod:
    	printk(KERN_INFO "cpu %d, %s %s, original stack not modified\n",
    			smp_processor_id(), type, msg);
    	return previous_current;
    }
    
    /* The monarch/slave interaction is based on monarch_cpu and requires that all
     * slaves have entered rendezvous before the monarch leaves.  If any cpu has
     * not entered rendezvous yet then wait a bit.  The assumption is that any
     * slave that has not rendezvoused after a reasonable time is never going to do
     * so.  In this context, slave includes cpus that respond to the MCA rendezvous
     * interrupt, as well as cpus that receive the INIT slave event.
     */
    
    static void
    ia64_wait_for_slaves(int monarch, const char *type)
    {
    	int c, i , wait;
    
    	/*
    	 * wait 5 seconds total for slaves (arbitrary)
    	 */
    	for (i = 0; i < 5000; i++) {
    		wait = 0;
    		for_each_online_cpu(c) {
    			if (c == monarch)
    				continue;
    			if (ia64_mc_info.imi_rendez_checkin[c]
    					== IA64_MCA_RENDEZ_CHECKIN_NOTDONE) {
    				udelay(1000);		/* short wait */
    				wait = 1;
    				break;
    			}
    		}
    		if (!wait)
    			goto all_in;
    	}
    
    	/*
    	 * Maybe slave(s) dead. Print buffered messages immediately.
    	 */
    	ia64_mlogbuf_finish(0);
    	mprintk(KERN_INFO "OS %s slave did not rendezvous on cpu", type);
    	for_each_online_cpu(c) {
    		if (c == monarch)
    			continue;
    		if (ia64_mc_info.imi_rendez_checkin[c] == IA64_MCA_RENDEZ_CHECKIN_NOTDONE)
    			mprintk(" %d", c);
    	}
    	mprintk("\n");
    	return;
    
    all_in:
    	mprintk(KERN_INFO "All OS %s slaves have reached rendezvous\n", type);
    	return;
    }
    
    /*
     * ia64_mca_handler
     *
     *	This is uncorrectable machine check handler called from OS_MCA
     *	dispatch code which is in turn called from SAL_CHECK().
     *	This is the place where the core of OS MCA handling is done.
     *	Right now the logs are extracted and displayed in a well-defined
     *	format. This handler code is supposed to be run only on the
     *	monarch processor. Once the monarch is done with MCA handling
     *	further MCA logging is enabled by clearing logs.
     *	Monarch also has the duty of sending wakeup-IPIs to pull the
     *	slave processors out of rendezvous spinloop.
     *
     *	If multiple processors call into OS_MCA, the first will become
     *	the monarch.  Subsequent cpus will be recorded in the mca_cpu
     *	bitmask.  After the first monarch has processed its MCA, it
     *	will wake up the next cpu in the mca_cpu bitmask and then go
     *	into the rendezvous loop.  When all processors have serviced
     *	their MCA, the last monarch frees up the rest of the processors.
     */
    void
    ia64_mca_handler(struct pt_regs *regs, struct switch_stack *sw,
    		 struct ia64_sal_os_state *sos)
    {
    	int recover, cpu = smp_processor_id();
    	struct task_struct *previous_current;
    	struct ia64_mca_notify_die nd =
    		{ .sos = sos, .monarch_cpu = &monarch_cpu };
    	static atomic_t mca_count;
    	static cpumask_t mca_cpu;
    
    	if (atomic_add_return(1, &mca_count) == 1) {
    		monarch_cpu = cpu;
    		sos->monarch = 1;
    	} else {
    		cpu_set(cpu, mca_cpu);
    		sos->monarch = 0;
    	}
    	mprintk(KERN_INFO "Entered OS MCA handler. PSP=%lx cpu=%d "
    		"monarch=%ld\n", sos->proc_state_param, cpu, sos->monarch);
    
    	previous_current = ia64_mca_modify_original_stack(regs, sw, sos, "MCA");
    
    	if (notify_die(DIE_MCA_MONARCH_ENTER, "MCA", regs, (long)&nd, 0, 0)
    			== NOTIFY_STOP)
    		ia64_mca_spin(__FUNCTION__);
    
    	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_CONCURRENT_MCA;
    	if (sos->monarch) {
    		ia64_wait_for_slaves(cpu, "MCA");
    
    		/* Wakeup all the processors which are spinning in the
    		 * rendezvous loop.  They will leave SAL, then spin in the OS
    		 * with interrupts disabled until this monarch cpu leaves the
    		 * MCA handler.  That gets control back to the OS so we can
    		 * backtrace the other cpus, backtrace when spinning in SAL
    		 * does not work.
    		 */
    		ia64_mca_wakeup_all();
    		if (notify_die(DIE_MCA_MONARCH_PROCESS, "MCA", regs, (long)&nd, 0, 0)
    				== NOTIFY_STOP)
    			ia64_mca_spin(__FUNCTION__);
    	} else {
    		while (cpu_isset(cpu, mca_cpu))
    			cpu_relax();	/* spin until monarch wakes us */
            }
    
    	/* Get the MCA error record and log it */
    	ia64_mca_log_sal_error_record(SAL_INFO_TYPE_MCA);
    
    	/* MCA error recovery */
    	recover = (ia64_mca_ucmc_extension
    		&& ia64_mca_ucmc_extension(
    			IA64_LOG_CURR_BUFFER(SAL_INFO_TYPE_MCA),
    			sos));
    
    	if (recover) {
    		sal_log_record_header_t *rh = IA64_LOG_CURR_BUFFER(SAL_INFO_TYPE_MCA);
    		rh->severity = sal_log_severity_corrected;
    		ia64_sal_clear_state_info(SAL_INFO_TYPE_MCA);
    		sos->os_status = IA64_MCA_CORRECTED;
    	} else {
    		/* Dump buffered message to console */
    		ia64_mlogbuf_finish(1);
    #ifdef CONFIG_KEXEC
    		atomic_set(&kdump_in_progress, 1);
    		monarch_cpu = -1;
    #endif
    	}
    	if (notify_die(DIE_MCA_MONARCH_LEAVE, "MCA", regs, (long)&nd, 0, recover)
    			== NOTIFY_STOP)
    		ia64_mca_spin(__FUNCTION__);
    
    
    	if (atomic_dec_return(&mca_count) > 0) {
    		int i;
    
    		/* wake up the next monarch cpu,
    		 * and put this cpu in the rendez loop.
    		 */
    		for_each_online_cpu(i) {
    			if (cpu_isset(i, mca_cpu)) {
    				monarch_cpu = i;
    				cpu_clear(i, mca_cpu);	/* wake next cpu */
    				while (monarch_cpu != -1)
    					cpu_relax();	/* spin until last cpu leaves */
    				set_curr_task(cpu, previous_current);
    				ia64_mc_info.imi_rendez_checkin[cpu]
    						= IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
    				return;
    			}
    		}
    	}
    	set_curr_task(cpu, previous_current);
    	ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
    	monarch_cpu = -1;	/* This frees the slaves and previous monarchs */
    }
    
    static DECLARE_WORK(cmc_disable_work, ia64_mca_cmc_vector_disable_keventd);
    static DECLARE_WORK(cmc_enable_work, ia64_mca_cmc_vector_enable_keventd);
    
    /*
     * ia64_mca_cmc_int_handler
     *
     *  This is corrected machine check interrupt handler.
     *	Right now the logs are extracted and displayed in a well-defined
     *	format.
     *
     * Inputs
     *      interrupt number
     *      client data arg ptr
     *
     * Outputs
     *	None
     */
    static irqreturn_t
    ia64_mca_cmc_int_handler(int cmc_irq, void *arg)
    {
    	static unsigned long	cmc_history[CMC_HISTORY_LENGTH];
    	static int		index;
    	static DEFINE_SPINLOCK(cmc_history_lock);
    
    	IA64_MCA_DEBUG("%s: received interrupt vector = %#x on CPU %d\n",
    		       __FUNCTION__, cmc_irq, smp_processor_id());
    
    	/* SAL spec states this should run w/ interrupts enabled */
    	local_irq_enable();
    
    	spin_lock(&cmc_history_lock);
    	if (!cmc_polling_enabled) {
    		int i, count = 1; /* we know 1 happened now */
    		unsigned long now = jiffies;
    
    		for (i = 0; i < CMC_HISTORY_LENGTH; i++) {
    			if (now - cmc_history[i] <= HZ)
    				count++;
    		}
    
    		IA64_MCA_DEBUG(KERN_INFO "CMC threshold %d/%d\n", count, CMC_HISTORY_LENGTH);
    		if (count >= CMC_HISTORY_LENGTH) {
    
    			cmc_polling_enabled = 1;
    			spin_unlock(&cmc_history_lock);
    			/* If we're being hit with CMC interrupts, we won't
    			 * ever execute the schedule_work() below.  Need to
    			 * disable CMC interrupts on this processor now.
    			 */
    			ia64_mca_cmc_vector_disable(NULL);
    			schedule_work(&cmc_disable_work);
    
    			/*
    			 * Corrected errors will still be corrected, but
    			 * make sure there's a log somewhere that indicates
    			 * something is generating more than we can handle.
    			 */
    			printk(KERN_WARNING "WARNING: Switching to polling CMC handler; error records may be lost\n");
    
    			mod_timer(&cmc_poll_timer, jiffies + CMC_POLL_INTERVAL);
    
    			/* lock already released, get out now */
    			goto out;
    		} else {
    			cmc_history[index++] = now;
    			if (index == CMC_HISTORY_LENGTH)
    				index = 0;
    		}
    	}
    	spin_unlock(&cmc_history_lock);
    out:
    	/* Get the CMC error record and log it */
    	ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CMC);
    
    	return IRQ_HANDLED;
    }
    
    /*
     *  ia64_mca_cmc_int_caller
     *
     * 	Triggered by sw interrupt from CMC polling routine.  Calls
     * 	real interrupt handler and either triggers a sw interrupt
     * 	on the next cpu or does cleanup at the end.
     *
     * Inputs
     *	interrupt number
     *	client data arg ptr
     * Outputs
     * 	handled
     */
    static irqreturn_t
    ia64_mca_cmc_int_caller(int cmc_irq, void *arg)
    {
    	static int start_count = -1;
    	unsigned int cpuid;
    
    	cpuid = smp_processor_id();
    
    	/* If first cpu, update count */
    	if (start_count == -1)
    		start_count = IA64_LOG_COUNT(SAL_INFO_TYPE_CMC);
    
    	ia64_mca_cmc_int_handler(cmc_irq, arg);
    
    	for (++cpuid ; cpuid < NR_CPUS && !cpu_online(cpuid) ; cpuid++);
    
    	if (cpuid < NR_CPUS) {
    		platform_send_ipi(cpuid, IA64_CMCP_VECTOR, IA64_IPI_DM_INT, 0);
    	} else {
    		/* If no log record, switch out of polling mode */
    		if (start_count == IA64_LOG_COUNT(SAL_INFO_TYPE_CMC)) {
    
    			printk(KERN_WARNING "Returning to interrupt driven CMC handler\n");
    			schedule_work(&cmc_enable_work);
    			cmc_polling_enabled = 0;
    
    		} else {
    
    			mod_timer(&cmc_poll_timer, jiffies + CMC_POLL_INTERVAL);
    		}
    
    		start_count = -1;
    	}
    
    	return IRQ_HANDLED;
    }
    
    /*
     *  ia64_mca_cmc_poll
     *
     *	Poll for Corrected Machine Checks (CMCs)
     *
     * Inputs   :   dummy(unused)
     * Outputs  :   None
     *
     */
    static void
    ia64_mca_cmc_poll (unsigned long dummy)
    {
    	/* Trigger a CMC interrupt cascade  */
    	platform_send_ipi(first_cpu(cpu_online_map), IA64_CMCP_VECTOR, IA64_IPI_DM_INT, 0);
    }
    
    /*
     *  ia64_mca_cpe_int_caller
     *
     * 	Triggered by sw interrupt from CPE polling routine.  Calls
     * 	real interrupt handler and either triggers a sw interrupt
     * 	on the next cpu or does cleanup at the end.
     *
     * Inputs
     *	interrupt number
     *	client data arg ptr
     * Outputs
     * 	handled
     */
    #ifdef CONFIG_ACPI
    
    static irqreturn_t
    ia64_mca_cpe_int_caller(int cpe_irq, void *arg)
    {
    	static int start_count = -1;
    	static int poll_time = MIN_CPE_POLL_INTERVAL;
    	unsigned int cpuid;
    
    	cpuid = smp_processor_id();
    
    	/* If first cpu, update count */
    	if (start_count == -1)
    		start_count = IA64_LOG_COUNT(SAL_INFO_TYPE_CPE);
    
    	ia64_mca_cpe_int_handler(cpe_irq, arg);
    
    	for (++cpuid ; cpuid < NR_CPUS && !cpu_online(cpuid) ; cpuid++);
    
    	if (cpuid < NR_CPUS) {
    		platform_send_ipi(cpuid, IA64_CPEP_VECTOR, IA64_IPI_DM_INT, 0);
    	} else {
    		/*
    		 * If a log was recorded, increase our polling frequency,
    		 * otherwise, backoff or return to interrupt mode.
    		 */
    		if (start_count != IA64_LOG_COUNT(SAL_INFO_TYPE_CPE)) {
    			poll_time = max(MIN_CPE_POLL_INTERVAL, poll_time / 2);
    		} else if (cpe_vector < 0) {
    			poll_time = min(MAX_CPE_POLL_INTERVAL, poll_time * 2);
    		} else {
    			poll_time = MIN_CPE_POLL_INTERVAL;
    
    			printk(KERN_WARNING "Returning to interrupt driven CPE handler\n");
    			enable_irq(local_vector_to_irq(IA64_CPE_VECTOR));
    			cpe_poll_enabled = 0;
    		}
    
    		if (cpe_poll_enabled)
    			mod_timer(&cpe_poll_timer, jiffies + poll_time);
    		start_count = -1;
    	}
    
    	return IRQ_HANDLED;
    }
    
    /*
     *  ia64_mca_cpe_poll
     *
     *	Poll for Corrected Platform Errors (CPEs), trigger interrupt
     *	on first cpu, from there it will trickle through all the cpus.
     *
     * Inputs   :   dummy(unused)
     * Outputs  :   None
     *
     */
    static void
    ia64_mca_cpe_poll (unsigned long dummy)
    {
    	/* Trigger a CPE interrupt cascade  */
    	platform_send_ipi(first_cpu(cpu_online_map), IA64_CPEP_VECTOR, IA64_IPI_DM_INT, 0);
    }
    
    #endif /* CONFIG_ACPI */
    
    static int
    default_monarch_init_process(struct notifier_block *self, unsigned long val, void *data)
    {
    	int c;
    	struct task_struct *g, *t;
    	if (val != DIE_INIT_MONARCH_PROCESS)
    		return NOTIFY_DONE;
    #ifdef CONFIG_KEXEC
    	if (atomic_read(&kdump_in_progress))
    		return NOTIFY_DONE;
    #endif
    
    	/*
    	 * FIXME: mlogbuf will brim over with INIT stack dumps.
    	 * To enable show_stack from INIT, we use oops_in_progress which should
    	 * be used in real oops. This would cause something wrong after INIT.
    	 */
    	BREAK_LOGLEVEL(console_loglevel);
    	ia64_mlogbuf_dump_from_init();
    
    	printk(KERN_ERR "Processes interrupted by INIT -");
    	for_each_online_cpu(c) {
    		struct ia64_sal_os_state *s;
    		t = __va(__per_cpu_mca[c] + IA64_MCA_CPU_INIT_STACK_OFFSET);
    		s = (struct ia64_sal_os_state *)((char *)t + MCA_SOS_OFFSET);
    		g = s->prev_task;
    		if (g) {
    			if (g->pid)
    				printk(" %d", g->pid);
    			else
    				printk(" %d (cpu %d task 0x%p)", g->pid, task_cpu(g), g);
    		}
    	}
    	printk("\n\n");
    	if (read_trylock(&tasklist_lock)) {
    		do_each_thread (g, t) {
    			printk("\nBacktrace of pid %d (%s)\n", t->pid, t->comm);
    			show_stack(t, NULL);
    		} while_each_thread (g, t);
    		read_unlock(&tasklist_lock);
    	}
    	/* FIXME: This will not restore zapped printk locks. */
    	RESTORE_LOGLEVEL(console_loglevel);
    	return NOTIFY_DONE;
    }
    
    /*
     * C portion of the OS INIT handler
     *
     * Called from ia64_os_init_dispatch
     *
     * Inputs: pointer to pt_regs where processor info was saved.  SAL/OS state for
     * this event.  This code is used for both monarch and slave INIT events, see
     * sos->monarch.
     *
     * All INIT events switch to the INIT stack and change the previous process to
     * blocked status.  If one of the INIT events is the monarch then we are
     * probably processing the nmi button/command.  Use the monarch cpu to dump all
     * the processes.  The slave INIT events all spin until the monarch cpu
     * returns.  We can also get INIT slave events for MCA, in which case the MCA
     * process is the monarch.
     */
    
    void
    ia64_init_handler(struct pt_regs *regs, struct switch_stack *sw,
    		  struct ia64_sal_os_state *sos)
    {
    	static atomic_t slaves;
    	static atomic_t monarchs;
    	struct task_struct *previous_current;
    	int cpu = smp_processor_id();
    	struct ia64_mca_notify_die nd =
    		{ .sos = sos, .monarch_cpu = &monarch_cpu };
    
    	(void) notify_die(DIE_INIT_ENTER, "INIT", regs, (long)&nd, 0, 0);
    
    	mprintk(KERN_INFO "Entered OS INIT handler. PSP=%lx cpu=%d monarch=%ld\n",
    		sos->proc_state_param, cpu, sos->monarch);
    	salinfo_log_wakeup(SAL_INFO_TYPE_INIT, NULL, 0, 0);
    
    	previous_current = ia64_mca_modify_original_stack(regs, sw, sos, "INIT");
    	sos->os_status = IA64_INIT_RESUME;
    
    	/* FIXME: Workaround for broken proms that drive all INIT events as
    	 * slaves.  The last slave that enters is promoted to be a monarch.
    	 * Remove this code in September 2006, that gives platforms a year to
    	 * fix their proms and get their customers updated.
    	 */
    	if (!sos->monarch && atomic_add_return(1, &slaves) == num_online_cpus()) {
    		mprintk(KERN_WARNING "%s: Promoting cpu %d to monarch.\n",
    		       __FUNCTION__, cpu);
    		atomic_dec(&slaves);
    		sos->monarch = 1;
    	}
    
    	/* FIXME: Workaround for broken proms that drive all INIT events as
    	 * monarchs.  Second and subsequent monarchs are demoted to slaves.
    	 * Remove this code in September 2006, that gives platforms a year to
    	 * fix their proms and get their customers updated.
    	 */
    	if (sos->monarch && atomic_add_return(1, &monarchs) > 1) {
    		mprintk(KERN_WARNING "%s: Demoting cpu %d to slave.\n",
    			       __FUNCTION__, cpu);
    		atomic_dec(&monarchs);
    		sos->monarch = 0;
    	}
    
    	if (!sos->monarch) {
    		ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_INIT;
    		while (monarch_cpu == -1)
    		       cpu_relax();	/* spin until monarch enters */
    		if (notify_die(DIE_INIT_SLAVE_ENTER, "INIT", regs, (long)&nd, 0, 0)
    				== NOTIFY_STOP)
    			ia64_mca_spin(__FUNCTION__);
    		if (notify_die(DIE_INIT_SLAVE_PROCESS, "INIT", regs, (long)&nd, 0, 0)
    				== NOTIFY_STOP)
    			ia64_mca_spin(__FUNCTION__);
    		while (monarch_cpu != -1)
    		       cpu_relax();	/* spin until monarch leaves */
    		if (notify_die(DIE_INIT_SLAVE_LEAVE, "INIT", regs, (long)&nd, 0, 0)
    				== NOTIFY_STOP)
    			ia64_mca_spin(__FUNCTION__);
    		mprintk("Slave on cpu %d returning to normal service.\n", cpu);
    		set_curr_task(cpu, previous_current);
    		ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
    		atomic_dec(&slaves);
    		return;
    	}
    
    	monarch_cpu = cpu;
    	if (notify_die(DIE_INIT_MONARCH_ENTER, "INIT", regs, (long)&nd, 0, 0)
    			== NOTIFY_STOP)
    		ia64_mca_spin(__FUNCTION__);
    
    	/*
    	 * Wait for a bit.  On some machines (e.g., HP's zx2000 and zx6000, INIT can be
    	 * generated via the BMC's command-line interface, but since the console is on the
    	 * same serial line, the user will need some time to switch out of the BMC before
    	 * the dump begins.
    	 */
    	mprintk("Delaying for 5 seconds...\n");
    	udelay(5*1000000);
    	ia64_wait_for_slaves(cpu, "INIT");
    	/* If nobody intercepts DIE_INIT_MONARCH_PROCESS then we drop through
    	 * to default_monarch_init_process() above and just print all the
    	 * tasks.
    	 */
    	if (notify_die(DIE_INIT_MONARCH_PROCESS, "INIT", regs, (long)&nd, 0, 0)
    			== NOTIFY_STOP)
    		ia64_mca_spin(__FUNCTION__);
    	if (notify_die(DIE_INIT_MONARCH_LEAVE, "INIT", regs, (long)&nd, 0, 0)
    			== NOTIFY_STOP)
    		ia64_mca_spin(__FUNCTION__);
    	mprintk("\nINIT dump complete.  Monarch on cpu %d returning to normal service.\n", cpu);
    	atomic_dec(&monarchs);
    	set_curr_task(cpu, previous_current);
    	monarch_cpu = -1;
    	return;
    }
    
    static int __init
    ia64_mca_disable_cpe_polling(char *str)
    {
    	cpe_poll_enabled = 0;
    	return 1;
    }
    
    __setup("disable_cpe_poll", ia64_mca_disable_cpe_polling);
    
    static struct irqaction cmci_irqaction = {
    	.handler =	ia64_mca_cmc_int_handler,
    	.flags =	IRQF_DISABLED,
    	.name =		"cmc_hndlr"
    };
    
    static struct irqaction cmcp_irqaction = {
    	.handler =	ia64_mca_cmc_int_caller,
    	.flags =	IRQF_DISABLED,
    	.name =		"cmc_poll"
    };
    
    static struct irqaction mca_rdzv_irqaction = {
    	.handler =	ia64_mca_rendez_int_handler,
    	.flags =	IRQF_DISABLED,
    	.name =		"mca_rdzv"
    };
    
    static struct irqaction mca_wkup_irqaction = {
    	.handler =	ia64_mca_wakeup_int_handler,
    	.flags =	IRQF_DISABLED,
    	.name =		"mca_wkup"
    };
    
    #ifdef CONFIG_ACPI
    static struct irqaction mca_cpe_irqaction = {
    	.handler =	ia64_mca_cpe_int_handler,
    	.flags =	IRQF_DISABLED,
    	.name =		"cpe_hndlr"
    };
    
    static struct irqaction mca_cpep_irqaction = {
    	.handler =	ia64_mca_cpe_int_caller,
    	.flags =	IRQF_DISABLED,
    	.name =		"cpe_poll"
    };
    #endif /* CONFIG_ACPI */
    
    /* Minimal format of the MCA/INIT stacks.  The pseudo processes that run on
     * these stacks can never sleep, they cannot return from the kernel to user
     * space, they do not appear in a normal ps listing.  So there is no need to
     * format most of the fields.
     */
    
    static void __cpuinit
    format_mca_init_stack(void *mca_data, unsigned long offset,
    		const char *type, int cpu)
    {
    	struct task_struct *p = (struct task_struct *)((char *)mca_data + offset);
    	struct thread_info *ti;
    	memset(p, 0, KERNEL_STACK_SIZE);
    	ti = task_thread_info(p);
    	ti->flags = _TIF_MCA_INIT;
    	ti->preempt_count = 1;
    	ti->task = p;
    	ti->cpu = cpu;
    	p->stack = ti;
    	p->state = TASK_UNINTERRUPTIBLE;
    	cpu_set(cpu, p->cpus_allowed);
    	INIT_LIST_HEAD(&p->tasks);
    	p->parent = p->real_parent = p->group_leader = p;
    	INIT_LIST_HEAD(&p->children);
    	INIT_LIST_HEAD(&p->sibling);
    	strncpy(p->comm, type, sizeof(p->comm)-1);
    }
    
    /* Caller prevents this from being called after init */
    static void * __init_refok mca_bootmem(void)
    {
    	void *p;
    
    	p = alloc_bootmem(sizeof(struct ia64_mca_cpu) * NR_CPUS +
    	                  KERNEL_STACK_SIZE);
    	return (void *)ALIGN((unsigned long)p, KERNEL_STACK_SIZE);
    }
    
    /* Do per-CPU MCA-related initialization.  */
    void __cpuinit
    ia64_mca_cpu_init(void *cpu_data)
    {
    	void *pal_vaddr;
    	static int first_time = 1;
    
    	if (first_time) {
    		void *mca_data;
    		int cpu;
    
    		first_time = 0;
    		mca_data = mca_bootmem();
    		for (cpu = 0; cpu < NR_CPUS; cpu++) {
    			format_mca_init_stack(mca_data,
    					offsetof(struct ia64_mca_cpu, mca_stack),
    					"MCA", cpu);
    			format_mca_init_stack(mca_data,
    					offsetof(struct ia64_mca_cpu, init_stack),
    					"INIT", cpu);
    			__per_cpu_mca[cpu] = __pa(mca_data);
    			mca_data += sizeof(struct ia64_mca_cpu);
    		}
    	}
    
    	/*
    	 * The MCA info structure was allocated earlier and its
    	 * physical address saved in __per_cpu_mca[cpu].  Copy that
    	 * address * to ia64_mca_data so we can access it as a per-CPU
    	 * variable.
    	 */
    	__get_cpu_var(ia64_mca_data) = __per_cpu_mca[smp_processor_id()];
    
    	/*
    	 * Stash away a copy of the PTE needed to map the per-CPU page.
    	 * We may need it during MCA recovery.
    	 */
    	__get_cpu_var(ia64_mca_per_cpu_pte) =
    		pte_val(mk_pte_phys(__pa(cpu_data), PAGE_KERNEL));
    
    	/*
    	 * Also, stash away a copy of the PAL address and the PTE
    	 * needed to map it.
    	 */
    	pal_vaddr = efi_get_pal_addr();
    	if (!pal_vaddr)
    		return;
    	__get_cpu_var(ia64_mca_pal_base) =
    		GRANULEROUNDDOWN((unsigned long) pal_vaddr);
    	__get_cpu_var(ia64_mca_pal_pte) = pte_val(mk_pte_phys(__pa(pal_vaddr),
    							      PAGE_KERNEL));
    }
    
    /*
     * ia64_mca_init
     *
     *  Do all the system level mca specific initialization.
     *
     *	1. Register spinloop and wakeup request interrupt vectors
     *
     *	2. Register OS_MCA handler entry point
     *
     *	3. Register OS_INIT handler entry point
     *
     *  4. Initialize MCA/CMC/INIT related log buffers maintained by the OS.
     *
     *  Note that this initialization is done very early before some kernel
     *  services are available.
     *
     *  Inputs  :   None
     *
     *  Outputs :   None
     */
    void __init
    ia64_mca_init(void)
    {
    	ia64_fptr_t *init_hldlr_ptr_monarch = (ia64_fptr_t *)ia64_os_init_dispatch_monarch;
    	ia64_fptr_t *init_hldlr_ptr_slave = (ia64_fptr_t *)ia64_os_init_dispatch_slave;
    	ia64_fptr_t *mca_hldlr_ptr = (ia64_fptr_t *)ia64_os_mca_dispatch;
    	int i;
    	s64 rc;
    	struct ia64_sal_retval isrv;
    	u64 timeout = IA64_MCA_RENDEZ_TIMEOUT;	/* platform specific */
    	static struct notifier_block default_init_monarch_nb = {
    		.notifier_call = default_monarch_init_process,
    		.priority = 0/* we need to notified last */
    	};
    
    	IA64_MCA_DEBUG("%s: begin\n", __FUNCTION__);
    
    	/* Clear the Rendez checkin flag for all cpus */
    	for(i = 0 ; i < NR_CPUS; i++)
    		ia64_mc_info.imi_rendez_checkin[i] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
    
    	/*
    	 * Register the rendezvous spinloop and wakeup mechanism with SAL
    	 */
    
    	/* Register the rendezvous interrupt vector with SAL */
    	while (1) {
    		isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_RENDEZ_INT,
    					      SAL_MC_PARAM_MECHANISM_INT,
    					      IA64_MCA_RENDEZ_VECTOR,
    					      timeout,
    					      SAL_MC_PARAM_RZ_ALWAYS);
    		rc = isrv.status;
    		if (rc == 0)
    			break;
    		if (rc == -2) {
    			printk(KERN_INFO "Increasing MCA rendezvous timeout from "
    				"%ld to %ld milliseconds\n", timeout, isrv.v0);
    			timeout = isrv.v0;
    			(void) notify_die(DIE_MCA_NEW_TIMEOUT, "MCA", NULL, timeout, 0, 0);
    			continue;
    		}
    		printk(KERN_ERR "Failed to register rendezvous interrupt "
    		       "with SAL (status %ld)\n", rc);
    		return;
    	}
    
    	/* Register the wakeup interrupt vector with SAL */
    	isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_RENDEZ_WAKEUP,
    				      SAL_MC_PARAM_MECHANISM_INT,
    				      IA64_MCA_WAKEUP_VECTOR,
    				      0, 0);
    	rc = isrv.status;
    	if (rc) {
    		printk(KERN_ERR "Failed to register wakeup interrupt with SAL "
    		       "(status %ld)\n", rc);
    		return;
    	}
    
    	IA64_MCA_DEBUG("%s: registered MCA rendezvous spinloop and wakeup mech.\n", __FUNCTION__);
    
    	ia64_mc_info.imi_mca_handler        = ia64_tpa(mca_hldlr_ptr->fp);
    	/*
    	 * XXX - disable SAL checksum by setting size to 0; should be
    	 *	ia64_tpa(ia64_os_mca_dispatch_end) - ia64_tpa(ia64_os_mca_dispatch);
    	 */
    	ia64_mc_info.imi_mca_handler_size	= 0;
    
    	/* Register the os mca handler with SAL */
    	if ((rc = ia64_sal_set_vectors(SAL_VECTOR_OS_MCA,
    				       ia64_mc_info.imi_mca_handler,
    				       ia64_tpa(mca_hldlr_ptr->gp),
    				       ia64_mc_info.imi_mca_handler_size,
    				       0, 0, 0)))
    	{
    		printk(KERN_ERR "Failed to register OS MCA handler with SAL "
    		       "(status %ld)\n", rc);
    		return;
    	}
    
    	IA64_MCA_DEBUG("%s: registered OS MCA handler with SAL at 0x%lx, gp = 0x%lx\n", __FUNCTION__,
    		       ia64_mc_info.imi_mca_handler, ia64_tpa(mca_hldlr_ptr->gp));
    
    	/*
    	 * XXX - disable SAL checksum by setting size to 0, should be
    	 * size of the actual init handler in mca_asm.S.
    	 */
    	ia64_mc_info.imi_monarch_init_handler		= ia64_tpa(init_hldlr_ptr_monarch->fp);
    	ia64_mc_info.imi_monarch_init_handler_size	= 0;
    	ia64_mc_info.imi_slave_init_handler		= ia64_tpa(init_hldlr_ptr_slave->fp);
    	ia64_mc_info.imi_slave_init_handler_size	= 0;
    
    	IA64_MCA_DEBUG("%s: OS INIT handler at %lx\n", __FUNCTION__,
    		       ia64_mc_info.imi_monarch_init_handler);
    
    	/* Register the os init handler with SAL */
    	if ((rc = ia64_sal_set_vectors(SAL_VECTOR_OS_INIT,
    				       ia64_mc_info.imi_monarch_init_handler,
    				       ia64_tpa(ia64_getreg(_IA64_REG_GP)),
    				       ia64_mc_info.imi_monarch_init_handler_size,
    				       ia64_mc_info.imi_slave_init_handler,
    				       ia64_tpa(ia64_getreg(_IA64_REG_GP)),
    				       ia64_mc_info.imi_slave_init_handler_size)))
    	{
    		printk(KERN_ERR "Failed to register m/s INIT handlers with SAL "
    		       "(status %ld)\n", rc);
    		return;
    	}
    	if (register_die_notifier(&default_init_monarch_nb)) {
    		printk(KERN_ERR "Failed to register default monarch INIT process\n");
    		return;
    	}
    
    	IA64_MCA_DEBUG("%s: registered OS INIT handler with SAL\n", __FUNCTION__);
    
    	/*
    	 *  Configure the CMCI/P vector and handler. Interrupts for CMC are
    	 *  per-processor, so AP CMC interrupts are setup in smp_callin() (smpboot.c).
    	 */
    	register_percpu_irq(IA64_CMC_VECTOR, &cmci_irqaction);
    	register_percpu_irq(IA64_CMCP_VECTOR, &cmcp_irqaction);
    	ia64_mca_cmc_vector_setup();       /* Setup vector on BSP */
    
    	/* Setup the MCA rendezvous interrupt vector */
    	register_percpu_irq(IA64_MCA_RENDEZ_VECTOR, &mca_rdzv_irqaction);
    
    	/* Setup the MCA wakeup interrupt vector */
    	register_percpu_irq(IA64_MCA_WAKEUP_VECTOR, &mca_wkup_irqaction);
    
    #ifdef CONFIG_ACPI
    	/* Setup the CPEI/P handler */
    	register_percpu_irq(IA64_CPEP_VECTOR, &mca_cpep_irqaction);
    #endif
    
    	/* Initialize the areas set aside by the OS to buffer the
    	 * platform/processor error states for MCA/INIT/CMC
    	 * handling.
    	 */
    	ia64_log_init(SAL_INFO_TYPE_MCA);
    	ia64_log_init(SAL_INFO_TYPE_INIT);
    	ia64_log_init(SAL_INFO_TYPE_CMC);
    	ia64_log_init(SAL_INFO_TYPE_CPE);
    
    	mca_init = 1;
    	printk(KERN_INFO "MCA related initialization done\n");
    }
    
    /*
     * ia64_mca_late_init
     *
     *	Opportunity to setup things that require initialization later
     *	than ia64_mca_init.  Setup a timer to poll for CPEs if the
     *	platform doesn't support an interrupt driven mechanism.
     *
     *  Inputs  :   None
     *  Outputs :   Status
     */
    static int __init
    ia64_mca_late_init(void)
    {
    	if (!mca_init)
    		return 0;
    
    	/* Setup the CMCI/P vector and handler */
    	init_timer(&cmc_poll_timer);
    	cmc_poll_timer.function = ia64_mca_cmc_poll;
    
    	/* Unmask/enable the vector */
    	cmc_polling_enabled = 0;
    	schedule_work(&cmc_enable_work);
    
    	IA64_MCA_DEBUG("%s: CMCI/P setup and enabled.\n", __FUNCTION__);
    
    #ifdef CONFIG_ACPI
    	/* Setup the CPEI/P vector and handler */
    	cpe_vector = acpi_request_vector(ACPI_INTERRUPT_CPEI);
    	init_timer(&cpe_poll_timer);
    	cpe_poll_timer.function = ia64_mca_cpe_poll;
    
    	{
    		irq_desc_t *desc;
    		unsigned int irq;
    
    		if (cpe_vector >= 0) {
    			/* If platform supports CPEI, enable the irq. */
    			irq = local_vector_to_irq(cpe_vector);
    			if (irq > 0) {
    				cpe_poll_enabled = 0;
    				desc = irq_desc + irq;
    				desc->status |= IRQ_PER_CPU;
    				setup_irq(irq, &mca_cpe_irqaction);
    				ia64_cpe_irq = irq;
    				ia64_mca_register_cpev(cpe_vector);
    				IA64_MCA_DEBUG("%s: CPEI/P setup and enabled.\n",
    					__FUNCTION__);
    				return 0;
    			}
    			printk(KERN_ERR "%s: Failed to find irq for CPE "
    					"interrupt handler, vector %d\n",
    					__FUNCTION__, cpe_vector);
    		}
    		/* If platform doesn't support CPEI, get the timer going. */
    		if (cpe_poll_enabled) {
    			ia64_mca_cpe_poll(0UL);
    			IA64_MCA_DEBUG("%s: CPEP setup and enabled.\n", __FUNCTION__);
    		}
    	}
    #endif
    
    	return 0;
    }
    
    device_initcall(ia64_mca_late_init);