1/* 2 * Copyright (C) 2012 - Virtual Open Systems and Columbia University 3 * Author: Christoffer Dall <c.dall@virtualopensystems.com> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License, version 2, as 7 * published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 17 */ 18 19#include <linux/linkage.h> 20 21 .text 22 23/******************************************************************** 24 * Call function in Hyp mode 25 * 26 * 27 * unsigned long kvm_call_hyp(void *hypfn, ...); 28 * 29 * This is not really a variadic function in the classic C-way and care must 30 * be taken when calling this to ensure parameters are passed in registers 31 * only, since the stack will change between the caller and the callee. 32 * 33 * Call the function with the first argument containing a pointer to the 34 * function you wish to call in Hyp mode, and subsequent arguments will be 35 * passed as r0, r1, and r2 (a maximum of 3 arguments in addition to the 36 * function pointer can be passed). The function being called must be mapped 37 * in Hyp mode (see init_hyp_mode in arch/arm/kvm/arm.c). Return values are 38 * passed in r0 (strictly 32bit). 39 * 40 * A function pointer with a value of 0xffffffff has a special meaning, 41 * and is used to implement __hyp_get_vectors in the same way as in 42 * arch/arm/kernel/hyp_stub.S. 43 * 44 * The calling convention follows the standard AAPCS: 45 * r0 - r3: caller save 46 * r12: caller save 47 * rest: callee save 48 */ 49ENTRY(kvm_call_hyp) 50 hvc #0 51 bx lr 52ENDPROC(kvm_call_hyp) 53