1/*	$OpenBSD: tcb.h,v 1.3 2016/10/02 20:11:32 guenther Exp $	*/
2
3/*
4 * Copyright (c) 2011 Philip Guenther <guenther@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19#ifndef _MACHINE_TCB_H_
20#define _MACHINE_TCB_H_
21
22#ifdef _KERNEL
23
24#include <machine/pcb.h>
25
26static inline void
27__arm_set_tcb(void *tcb)
28{
29	__asm volatile("mcr p15, 0, %0, c13, c0, 3\n" : : "r" (tcb));
30}
31
32#define TCB_GET(p)		\
33	((struct pcb *)(p)->p_addr)->pcb_tcb
34
35#define TCB_SET(p, addr)	\
36	do {							\
37		((struct pcb *)(p)->p_addr)->pcb_tcb = (addr);	\
38		__arm_set_tcb(addr);				\
39	} while (0)
40
41#else /* _KERNEL */
42
43/* ELF TLS ABI calls for small TCB, with static TLS data after it */
44#define TLS_VARIANT	1
45
46static inline void *
47__arm_read_tcb(void)
48{
49	void *tcb;
50	__asm volatile("mrc p15, 0, %0, c13, c0, 3\n" : "=r" (tcb));
51	return tcb;
52}
53
54#define TCB_GET()		__arm_read_tcb()
55
56#endif /* _KERNEL */
57
58#endif /* _MACHINE_TCB_H_ */
59