1/*-
2 * Copyright (c) 2005 David Xu <davidxu@freebsd.org>
3 * Copyright (c) 2015 Ruslan Bukin <br@bsdpad.com>
4 * All rights reserved.
5 *
6 * Portions of this software were developed by SRI International and the
7 * University of Cambridge Computer Laboratory under DARPA/AFRL contract
8 * FA8750-10-C-0237 ("CTSRD"), as part of the DARPA CRASH research programme.
9 *
10 * Portions of this software were developed by the University of Cambridge
11 * Computer Laboratory as part of the CTSRD Project, with support from the
12 * UK Higher Education Innovation Fund (HEIF).
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 * 1. Redistributions of source code must retain the above copyright
18 *    notice, this list of conditions and the following disclaimer.
19 * 2. Redistributions in binary form must reproduce the above copyright
20 *    notice, this list of conditions and the following disclaimer in the
21 *    documentation and/or other materials provided with the distribution.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * $FreeBSD: stable/11/lib/libthr/arch/riscv/include/pthread_md.h 319430 2017-06-01 14:49:53Z vangyzen $
36 */
37
38/*
39 * Machine-dependent thread prototypes/definitions.
40 */
41#ifndef _PTHREAD_MD_H_
42#define	_PTHREAD_MD_H_
43
44#include <sys/types.h>
45#include <stddef.h>
46
47#define	CPU_SPINWAIT
48#define	DTV_OFFSET		offsetof(struct tcb, tcb_dtv)
49#define	TP_OFFSET		sizeof(struct tcb)
50
51/*
52 * Variant I tcb. The structure layout is fixed, don't blindly
53 * change it!
54 */
55struct tcb {
56	void			*tcb_dtv;
57	struct pthread		*tcb_thread;
58};
59
60/* Called from the thread to set its private data. */
61static __inline void
62_tcb_set(struct tcb *tcb)
63{
64
65	__asm __volatile("mv tp, %0" :: "r"((uint8_t *)tcb + TP_OFFSET));
66}
67
68/*
69 * Get the current tcb.
70 */
71static __inline struct tcb *
72_tcb_get(void)
73{
74	register uint8_t *_tp;
75
76	__asm __volatile("mv %0, tp" : "=r"(_tp));
77
78	return ((struct tcb *)(_tp - TP_OFFSET));
79}
80
81static __inline struct pthread *
82_get_curthread(void)
83{
84
85	if (_thr_initial)
86		return (_tcb_get()->tcb_thread);
87	return (NULL);
88}
89
90#endif /* _PTHREAD_MD_H_ */
91