xref: /linux/arch/arm64/include/asm/semihost.h (revision 2697b79a469b68e3ad3640f55284359c1396278d)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2012 ARM Ltd.
4  * Author: Marc Zyngier <marc.zyngier@arm.com>
5  *
6  * Adapted for ARM and earlycon:
7  * Copyright (C) 2014 Linaro Ltd.
8  * Author: Rob Herring <robh@kernel.org>
9  */
10 
11 #ifndef _ARM64_SEMIHOST_H_
12 #define _ARM64_SEMIHOST_H_
13 
14 struct uart_port;
15 
16 static inline void smh_putc(struct uart_port *port, unsigned char c)
17 {
18 	asm volatile("mov  x1, %0\n"
19 		     "mov  x0, #3\n"
20 		     "hlt  0xf000\n"
21 		     : : "r" (&c) : "x0", "x1", "memory");
22 }
23 
24 #endif /* _ARM64_SEMIHOST_H_ */
25