| /* |
| * Copyright (C) 2012,2013 - ARM Ltd |
| * Author: Marc Zyngier <marc.zyngier@arm.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, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include <linux/linkage.h> |
| |
| #include <asm/alternative.h> |
| #include <asm/assembler.h> |
| #include <asm/cpufeature.h> |
| |
| /* |
| * u64 __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 x0, x1, and x2 (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 x0. |
| * |
| * A function pointer with a value less than 0xfff has a special meaning, |
| * and is used to implement hyp stubs in the same way as in |
| * arch/arm64/kernel/hyp_stub.S. |
| */ |
| ENTRY(__kvm_call_hyp) |
| alternative_if_not ARM64_HAS_VIRT_HOST_EXTN |
| hvc #0 |
| ret |
| alternative_else_nop_endif |
| b __vhe_hyp_call |
| ENDPROC(__kvm_call_hyp) |