1// SPDX-License-Identifier: GPL-2.0
2/*
3 * mp.c:  OpenBoot Prom Multiprocessor support routines.  Don't call
4 *        these on a UP or else you will halt and catch fire. ;)
5 *
6 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
7 */
8
9#include <linux/types.h>
10#include <linux/kernel.h>
11#include <linux/sched.h>
12
13#include <asm/openprom.h>
14#include <asm/oplib.h>
15
16extern void restore_current(void);
17
18/* Start cpu with prom-tree node 'cpunode' using context described
19 * by 'ctable_reg' in context 'ctx' at program counter 'pc'.
20 *
21 * XXX Have to look into what the return values mean. XXX
22 */
23int
24prom_startcpu(int cpunode, struct linux_prom_registers *ctable_reg, int ctx, char *pc)
25{
26	int ret;
27	unsigned long flags;
28
29	spin_lock_irqsave(&prom_lock, flags);
30	switch(prom_vers) {
31	case PROM_V0:
32	case PROM_V2:
33	default:
34		ret = -1;
35		break;
36	case PROM_V3:
37		ret = (*(romvec->v3_cpustart))(cpunode, (int) ctable_reg, ctx, pc);
38		break;
39	}
40	restore_current();
41	spin_unlock_irqrestore(&prom_lock, flags);
42
43	return ret;
44}
45