1/*
  2 * Copyright Altera Corporation (C) <2014>. All rights reserved
  3 *
  4 * This program is free software; you can redistribute it and/or modify it
  5 * under the terms and conditions of the GNU General Public License,
  6 * version 2, as published by the Free Software Foundation.
  7 *
  8 * This program is distributed in the hope it will be useful, but WITHOUT
  9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 10 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 11 * more details.
 12 *
 13 * You should have received a copy of the GNU General Public License along with
 14 * this program.  If not, see <http://www.gnu.org/licenses/>.
 15 */
 16
 17#ifndef __ASM_NIOS2_SYSCALL_H__
 18#define __ASM_NIOS2_SYSCALL_H__
 19
 20#include <linux/err.h>
 21#include <linux/sched.h>
 22
 23static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
 24{
 25	return regs->r2;
 26}
 27
 28static inline void syscall_rollback(struct task_struct *task,
 29				struct pt_regs *regs)
 30{
 31	regs->r2 = regs->orig_r2;
 32	regs->r7 = regs->orig_r7;
 33}
 34
 35static inline long syscall_get_error(struct task_struct *task,
 36				struct pt_regs *regs)
 37{
 38	return regs->r7 ? regs->r2 : 0;
 39}
 40
 41static inline long syscall_get_return_value(struct task_struct *task,
 42	struct pt_regs *regs)
 43{
 44	return regs->r2;
 45}
 46
 47static inline void syscall_set_return_value(struct task_struct *task,
 48	struct pt_regs *regs, int error, long val)
 49{
 50	if (error) {
 51		/* error < 0, but nios2 uses > 0 return value */
 52		regs->r2 = -error;
 53		regs->r7 = 1;
 54	} else {
 55		regs->r2 = val;
 56		regs->r7 = 0;
 57	}
 58}
 59
 60static inline void syscall_get_arguments(struct task_struct *task,
 61	struct pt_regs *regs, unsigned int i, unsigned int n,
 62	unsigned long *args)
 63{
 64	BUG_ON(i + n > 6);
 65
 66	switch (i) {
 67	case 0:
 68		if (!n--)
 69			break;
 70		*args++ = regs->r4;
 71	case 1:
 72		if (!n--)
 73			break;
 74		*args++ = regs->r5;
 75	case 2:
 76		if (!n--)
 77			break;
 78		*args++ = regs->r6;
 79	case 3:
 80		if (!n--)
 81			break;
 82		*args++ = regs->r7;
 83	case 4:
 84		if (!n--)
 85			break;
 86		*args++ = regs->r8;
 87	case 5:
 88		if (!n--)
 89			break;
 90		*args++ = regs->r9;
 91	case 6:
 92		if (!n--)
 93			break;
 94	default:
 95		BUG();
 96	}
 97}
 98
 99static inline void syscall_set_arguments(struct task_struct *task,
100	struct pt_regs *regs, unsigned int i, unsigned int n,
101	const unsigned long *args)
102{
103	BUG_ON(i + n > 6);
104
105	switch (i) {
106	case 0:
107		if (!n--)
108			break;
109		regs->r4 = *args++;
110	case 1:
111		if (!n--)
112			break;
113		regs->r5 = *args++;
114	case 2:
115		if (!n--)
116			break;
117		regs->r6 = *args++;
118	case 3:
119		if (!n--)
120			break;
121		regs->r7 = *args++;
122	case 4:
123		if (!n--)
124			break;
125		regs->r8 = *args++;
126	case 5:
127		if (!n--)
128			break;
129		regs->r9 = *args++;
130	case 6:
131		if (!n)
132			break;
133	default:
134		BUG();
135	}
136}
137
138#endif