1 /* $Id: mp.c,v 1.12 2000/08/26 02:38:03 anton Exp $
2 * mp.c: OpenBoot Prom Multiprocessor support routines. Don't call
3 * these on a UP or else you will halt and catch fire. ;)
4 *
5 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
6 */
7
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <linux/sched.h>
11
12 #include <asm/openprom.h>
13 #include <asm/oplib.h>
14
15 extern void restore_current(void);
16
17 /* Start cpu with prom-tree node 'cpunode' using context described
18 * by 'ctable_reg' in context 'ctx' at program counter 'pc'.
19 *
20 * XXX Have to look into what the return values mean. XXX
21 */
22 int
prom_startcpu(int cpunode,struct linux_prom_registers * ctable_reg,int ctx,char * pc)23 prom_startcpu(int cpunode, struct linux_prom_registers *ctable_reg, int ctx, char *pc)
24 {
25 int ret;
26 unsigned long flags;
27
28 spin_lock_irqsave(&prom_lock, flags);
29 switch(prom_vers) {
30 case PROM_V0:
31 case PROM_V2:
32 default:
33 ret = -1;
34 break;
35 case PROM_V3:
36 ret = (*(romvec->v3_cpustart))(cpunode, (int) ctable_reg, ctx, pc);
37 break;
38 };
39 restore_current();
40 spin_unlock_irqrestore(&prom_lock, flags);
41
42 return ret;
43 }
44
45 /* Stop CPU with device prom-tree node 'cpunode'.
46 * XXX Again, what does the return value really mean? XXX
47 */
48 int
prom_stopcpu(int cpunode)49 prom_stopcpu(int cpunode)
50 {
51 int ret;
52 unsigned long flags;
53
54 spin_lock_irqsave(&prom_lock, flags);
55 switch(prom_vers) {
56 case PROM_V0:
57 case PROM_V2:
58 default:
59 ret = -1;
60 break;
61 case PROM_V3:
62 ret = (*(romvec->v3_cpustop))(cpunode);
63 break;
64 };
65 restore_current();
66 spin_unlock_irqrestore(&prom_lock, flags);
67
68 return ret;
69 }
70
71 /* Make CPU with device prom-tree node 'cpunode' idle.
72 * XXX Return value, anyone? XXX
73 */
74 int
prom_idlecpu(int cpunode)75 prom_idlecpu(int cpunode)
76 {
77 int ret;
78 unsigned long flags;
79
80 spin_lock_irqsave(&prom_lock, flags);
81 switch(prom_vers) {
82 case PROM_V0:
83 case PROM_V2:
84 default:
85 ret = -1;
86 break;
87 case PROM_V3:
88 ret = (*(romvec->v3_cpuidle))(cpunode);
89 break;
90 };
91 restore_current();
92 spin_unlock_irqrestore(&prom_lock, flags);
93
94 return ret;
95 }
96
97 /* Resume the execution of CPU with nodeid 'cpunode'.
98 * XXX Come on, somebody has to know... XXX
99 */
100 int
prom_restartcpu(int cpunode)101 prom_restartcpu(int cpunode)
102 {
103 int ret;
104 unsigned long flags;
105
106 spin_lock_irqsave(&prom_lock, flags);
107 switch(prom_vers) {
108 case PROM_V0:
109 case PROM_V2:
110 default:
111 ret = -1;
112 break;
113 case PROM_V3:
114 ret = (*(romvec->v3_cpuresume))(cpunode);
115 break;
116 };
117 restore_current();
118 spin_unlock_irqrestore(&prom_lock, flags);
119
120 return ret;
121 }
122