/*
   * 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)