1 /* 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 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 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 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 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