xref: /openbmc/linux/arch/sparc/kernel/smp_32.c (revision 95e9fd10)
1 /* smp.c: Sparc SMP support.
2  *
3  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
4  * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
5  * Copyright (C) 2004 Keith M Wesolowski (wesolows@foobazco.org)
6  */
7 
8 #include <asm/head.h>
9 
10 #include <linux/kernel.h>
11 #include <linux/sched.h>
12 #include <linux/threads.h>
13 #include <linux/smp.h>
14 #include <linux/interrupt.h>
15 #include <linux/kernel_stat.h>
16 #include <linux/init.h>
17 #include <linux/spinlock.h>
18 #include <linux/mm.h>
19 #include <linux/fs.h>
20 #include <linux/seq_file.h>
21 #include <linux/cache.h>
22 #include <linux/delay.h>
23 
24 #include <asm/ptrace.h>
25 #include <linux/atomic.h>
26 
27 #include <asm/irq.h>
28 #include <asm/page.h>
29 #include <asm/pgalloc.h>
30 #include <asm/pgtable.h>
31 #include <asm/oplib.h>
32 #include <asm/cacheflush.h>
33 #include <asm/tlbflush.h>
34 #include <asm/cpudata.h>
35 #include <asm/leon.h>
36 
37 #include "irq.h"
38 
39 volatile unsigned long cpu_callin_map[NR_CPUS] __cpuinitdata = {0,};
40 
41 cpumask_t smp_commenced_mask = CPU_MASK_NONE;
42 
43 const struct sparc32_ipi_ops *sparc32_ipi_ops;
44 
45 /* The only guaranteed locking primitive available on all Sparc
46  * processors is 'ldstub [%reg + immediate], %dest_reg' which atomically
47  * places the current byte at the effective address into dest_reg and
48  * places 0xff there afterwards.  Pretty lame locking primitive
49  * compared to the Alpha and the Intel no?  Most Sparcs have 'swap'
50  * instruction which is much better...
51  */
52 
53 void __cpuinit smp_store_cpu_info(int id)
54 {
55 	int cpu_node;
56 	int mid;
57 
58 	cpu_data(id).udelay_val = loops_per_jiffy;
59 
60 	cpu_find_by_mid(id, &cpu_node);
61 	cpu_data(id).clock_tick = prom_getintdefault(cpu_node,
62 						     "clock-frequency", 0);
63 	cpu_data(id).prom_node = cpu_node;
64 	mid = cpu_get_hwmid(cpu_node);
65 
66 	if (mid < 0) {
67 		printk(KERN_NOTICE "No MID found for CPU%d at node 0x%08d", id, cpu_node);
68 		mid = 0;
69 	}
70 	cpu_data(id).mid = mid;
71 }
72 
73 void __init smp_cpus_done(unsigned int max_cpus)
74 {
75 	extern void smp4m_smp_done(void);
76 	extern void smp4d_smp_done(void);
77 	unsigned long bogosum = 0;
78 	int cpu, num = 0;
79 
80 	for_each_online_cpu(cpu) {
81 		num++;
82 		bogosum += cpu_data(cpu).udelay_val;
83 	}
84 
85 	printk("Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
86 		num, bogosum/(500000/HZ),
87 		(bogosum/(5000/HZ))%100);
88 
89 	switch(sparc_cpu_model) {
90 	case sun4m:
91 		smp4m_smp_done();
92 		break;
93 	case sun4d:
94 		smp4d_smp_done();
95 		break;
96 	case sparc_leon:
97 		leon_smp_done();
98 		break;
99 	case sun4e:
100 		printk("SUN4E\n");
101 		BUG();
102 		break;
103 	case sun4u:
104 		printk("SUN4U\n");
105 		BUG();
106 		break;
107 	default:
108 		printk("UNKNOWN!\n");
109 		BUG();
110 		break;
111 	}
112 }
113 
114 void cpu_panic(void)
115 {
116 	printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
117 	panic("SMP bolixed\n");
118 }
119 
120 struct linux_prom_registers smp_penguin_ctable __cpuinitdata = { 0 };
121 
122 void smp_send_reschedule(int cpu)
123 {
124 	/*
125 	 * CPU model dependent way of implementing IPI generation targeting
126 	 * a single CPU. The trap handler needs only to do trap entry/return
127 	 * to call schedule.
128 	 */
129 	sparc32_ipi_ops->resched(cpu);
130 }
131 
132 void smp_send_stop(void)
133 {
134 }
135 
136 void arch_send_call_function_single_ipi(int cpu)
137 {
138 	/* trigger one IPI single call on one CPU */
139 	sparc32_ipi_ops->single(cpu);
140 }
141 
142 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
143 {
144 	int cpu;
145 
146 	/* trigger IPI mask call on each CPU */
147 	for_each_cpu(cpu, mask)
148 		sparc32_ipi_ops->mask_one(cpu);
149 }
150 
151 void smp_resched_interrupt(void)
152 {
153 	irq_enter();
154 	scheduler_ipi();
155 	local_cpu_data().irq_resched_count++;
156 	irq_exit();
157 	/* re-schedule routine called by interrupt return code. */
158 }
159 
160 void smp_call_function_single_interrupt(void)
161 {
162 	irq_enter();
163 	generic_smp_call_function_single_interrupt();
164 	local_cpu_data().irq_call_count++;
165 	irq_exit();
166 }
167 
168 void smp_call_function_interrupt(void)
169 {
170 	irq_enter();
171 	generic_smp_call_function_interrupt();
172 	local_cpu_data().irq_call_count++;
173 	irq_exit();
174 }
175 
176 int setup_profiling_timer(unsigned int multiplier)
177 {
178 	return -EINVAL;
179 }
180 
181 void __init smp_prepare_cpus(unsigned int max_cpus)
182 {
183 	extern void __init smp4m_boot_cpus(void);
184 	extern void __init smp4d_boot_cpus(void);
185 	int i, cpuid, extra;
186 
187 	printk("Entering SMP Mode...\n");
188 
189 	extra = 0;
190 	for (i = 0; !cpu_find_by_instance(i, NULL, &cpuid); i++) {
191 		if (cpuid >= NR_CPUS)
192 			extra++;
193 	}
194 	/* i = number of cpus */
195 	if (extra && max_cpus > i - extra)
196 		printk("Warning: NR_CPUS is too low to start all cpus\n");
197 
198 	smp_store_cpu_info(boot_cpu_id);
199 
200 	switch(sparc_cpu_model) {
201 	case sun4m:
202 		smp4m_boot_cpus();
203 		break;
204 	case sun4d:
205 		smp4d_boot_cpus();
206 		break;
207 	case sparc_leon:
208 		leon_boot_cpus();
209 		break;
210 	case sun4e:
211 		printk("SUN4E\n");
212 		BUG();
213 		break;
214 	case sun4u:
215 		printk("SUN4U\n");
216 		BUG();
217 		break;
218 	default:
219 		printk("UNKNOWN!\n");
220 		BUG();
221 		break;
222 	}
223 }
224 
225 /* Set this up early so that things like the scheduler can init
226  * properly.  We use the same cpu mask for both the present and
227  * possible cpu map.
228  */
229 void __init smp_setup_cpu_possible_map(void)
230 {
231 	int instance, mid;
232 
233 	instance = 0;
234 	while (!cpu_find_by_instance(instance, NULL, &mid)) {
235 		if (mid < NR_CPUS) {
236 			set_cpu_possible(mid, true);
237 			set_cpu_present(mid, true);
238 		}
239 		instance++;
240 	}
241 }
242 
243 void __init smp_prepare_boot_cpu(void)
244 {
245 	int cpuid = hard_smp_processor_id();
246 
247 	if (cpuid >= NR_CPUS) {
248 		prom_printf("Serious problem, boot cpu id >= NR_CPUS\n");
249 		prom_halt();
250 	}
251 	if (cpuid != 0)
252 		printk("boot cpu id != 0, this could work but is untested\n");
253 
254 	current_thread_info()->cpu = cpuid;
255 	set_cpu_online(cpuid, true);
256 	set_cpu_possible(cpuid, true);
257 }
258 
259 int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *tidle)
260 {
261 	extern int __cpuinit smp4m_boot_one_cpu(int, struct task_struct *);
262 	extern int __cpuinit smp4d_boot_one_cpu(int, struct task_struct *);
263 	int ret=0;
264 
265 	switch(sparc_cpu_model) {
266 	case sun4m:
267 		ret = smp4m_boot_one_cpu(cpu, tidle);
268 		break;
269 	case sun4d:
270 		ret = smp4d_boot_one_cpu(cpu, tidle);
271 		break;
272 	case sparc_leon:
273 		ret = leon_boot_one_cpu(cpu, tidle);
274 		break;
275 	case sun4e:
276 		printk("SUN4E\n");
277 		BUG();
278 		break;
279 	case sun4u:
280 		printk("SUN4U\n");
281 		BUG();
282 		break;
283 	default:
284 		printk("UNKNOWN!\n");
285 		BUG();
286 		break;
287 	}
288 
289 	if (!ret) {
290 		cpumask_set_cpu(cpu, &smp_commenced_mask);
291 		while (!cpu_online(cpu))
292 			mb();
293 	}
294 	return ret;
295 }
296 
297 void smp_bogo(struct seq_file *m)
298 {
299 	int i;
300 
301 	for_each_online_cpu(i) {
302 		seq_printf(m,
303 			   "Cpu%dBogo\t: %lu.%02lu\n",
304 			   i,
305 			   cpu_data(i).udelay_val/(500000/HZ),
306 			   (cpu_data(i).udelay_val/(5000/HZ))%100);
307 	}
308 }
309 
310 void smp_info(struct seq_file *m)
311 {
312 	int i;
313 
314 	seq_printf(m, "State:\n");
315 	for_each_online_cpu(i)
316 		seq_printf(m, "CPU%d\t\t: online\n", i);
317 }
318