linux-sg2042/arch/ia64/xen/xenivt.S

53 lines
1.2 KiB
ArmAsm

/*
* 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)