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/*
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
* Author: Christoffer Dall <c.dall@virtualopensystems.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2, as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <linux/linkage.h>
.text
/********************************************************************
* Call function in Hyp mode
*
*
* unsigned long kvm_call_hyp(void *hypfn, ...);
*
* This is not really a variadic function in the classic C-way and care must
* be taken when calling this to ensure parameters are passed in registers
* only, since the stack will change between the caller and the callee.
*
* Call the function with the first argument containing a pointer to the
* function you wish to call in Hyp mode, and subsequent arguments will be
* passed as r0, r1, and r2 (a maximum of 3 arguments in addition to the
* function pointer can be passed). The function being called must be mapped
* in Hyp mode (see init_hyp_mode in arch/arm/kvm/arm.c). Return values are
* passed in r0 (strictly 32bit).
*
* A function pointer with a value of 0xffffffff has a special meaning,
* and is used to implement __hyp_get_vectors in the same way as in
* arch/arm/kernel/hyp_stub.S.
*
* The calling convention follows the standard AAPCS:
* r0 - r3: caller save
* r12: caller save
* rest: callee save
*/
ENTRY(kvm_call_hyp)
hvc #0
bx lr
ENDPROC(kvm_call_hyp)