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/*
 * arch/ia64/xen/ivt.S
 *
 * Copyright (C) 2005 Hewlett-Packard Co
 *	Dan Magenheimer <dan.magenheimer@hp.com>
 *
 * Copyright (c) 2008 Isaku Yamahata <yamahata at valinux co jp>
 *                    VA Linux Systems Japan K.K.
 *                    pv_ops.
 */

#include <asm/asmmacro.h>
#include <asm/kregs.h>
#include <asm/pgtable.h>

#include "../kernel/minstate.h"

	.section .text,"ax"
GLOBAL_ENTRY(xen_event_callback)
	mov r31=pr		// prepare to save predicates
	;;
	SAVE_MIN_WITH_COVER	// uses r31; defines r2 and r3
	;;
	movl r3=XSI_PSR_IC
	mov r14=1
	;;
	st4 [r3]=r14
	;;
	adds r3=8,r2		// set up second base pointer for SAVE_REST
	srlz.i			// ensure everybody knows psr.ic is back on
	;;
	SAVE_REST
	;;
1:
	alloc r14=ar.pfs,0,0,1,0 // must be first in an insn group
	add out0=16,sp		// pass pointer to pt_regs as first arg
	;;
	br.call.sptk.many b0=xen_evtchn_do_upcall
	;;
	movl r20=XSI_PSR_I_ADDR
	;;
	ld8 r20=[r20]
	;;
	adds r20=-1,r20		// vcpu_info->evtchn_upcall_pending
	;;
	ld1 r20=[r20]
	;;
	cmp.ne p6,p0=r20,r0	// if there are pending events,
	(p6) br.spnt.few 1b	// call evtchn_do_upcall again.
	br.sptk.many xen_leave_kernel	// we know ia64_leave_kernel is
					// paravirtualized as xen_leave_kernel
END(xen_event_callback)