xref: /openbmc/linux/arch/sparc/kernel/smp_32.c (revision 293d5b43)
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 #include <linux/profile.h>
24 #include <linux/cpu.h>
25 
26 #include <asm/ptrace.h>
27 #include <linux/atomic.h>
28 
29 #include <asm/irq.h>
30 #include <asm/page.h>
31 #include <asm/pgalloc.h>
32 #include <asm/pgtable.h>
33 #include <asm/oplib.h>
34 #include <asm/cacheflush.h>
35 #include <asm/tlbflush.h>
36 #include <asm/cpudata.h>
37 #include <asm/timer.h>
38 #include <asm/leon.h>
39 
40 #include "kernel.h"
41 #include "irq.h"
42 
43 volatile unsigned long cpu_callin_map[NR_CPUS] = {0,};
44 
45 cpumask_t smp_commenced_mask = CPU_MASK_NONE;
46 
47 const struct sparc32_ipi_ops *sparc32_ipi_ops;
48 
49 /* The only guaranteed locking primitive available on all Sparc
50  * processors is 'ldstub [%reg + immediate], %dest_reg' which atomically
51  * places the current byte at the effective address into dest_reg and
52  * places 0xff there afterwards.  Pretty lame locking primitive
53  * compared to the Alpha and the Intel no?  Most Sparcs have 'swap'
54  * instruction which is much better...
55  */
56 
57 void smp_store_cpu_info(int id)
58 {
59 	int cpu_node;
60 	int mid;
61 
62 	cpu_data(id).udelay_val = loops_per_jiffy;
63 
64 	cpu_find_by_mid(id, &cpu_node);
65 	cpu_data(id).clock_tick = prom_getintdefault(cpu_node,
66 						     "clock-frequency", 0);
67 	cpu_data(id).prom_node = cpu_node;
68 	mid = cpu_get_hwmid(cpu_node);
69 
70 	if (mid < 0) {
71 		printk(KERN_NOTICE "No MID found for CPU%d at node 0x%08x", id, cpu_node);
72 		mid = 0;
73 	}
74 	cpu_data(id).mid = mid;
75 }
76 
77 void __init smp_cpus_done(unsigned int max_cpus)
78 {
79 	unsigned long bogosum = 0;
80 	int cpu, num = 0;
81 
82 	for_each_online_cpu(cpu) {
83 		num++;
84 		bogosum += cpu_data(cpu).udelay_val;
85 	}
86 
87 	printk("Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
88 		num, bogosum/(500000/HZ),
89 		(bogosum/(5000/HZ))%100);
90 
91 	switch(sparc_cpu_model) {
92 	case sun4m:
93 		smp4m_smp_done();
94 		break;
95 	case sun4d:
96 		smp4d_smp_done();
97 		break;
98 	case sparc_leon:
99 		leon_smp_done();
100 		break;
101 	case sun4e:
102 		printk("SUN4E\n");
103 		BUG();
104 		break;
105 	case sun4u:
106 		printk("SUN4U\n");
107 		BUG();
108 		break;
109 	default:
110 		printk("UNKNOWN!\n");
111 		BUG();
112 		break;
113 	}
114 }
115 
116 void cpu_panic(void)
117 {
118 	printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
119 	panic("SMP bolixed\n");
120 }
121 
122 struct linux_prom_registers smp_penguin_ctable = { 0 };
123 
124 void smp_send_reschedule(int cpu)
125 {
126 	/*
127 	 * CPU model dependent way of implementing IPI generation targeting
128 	 * a single CPU. The trap handler needs only to do trap entry/return
129 	 * to call schedule.
130 	 */
131 	sparc32_ipi_ops->resched(cpu);
132 }
133 
134 void smp_send_stop(void)
135 {
136 }
137 
138 void arch_send_call_function_single_ipi(int cpu)
139 {
140 	/* trigger one IPI single call on one CPU */
141 	sparc32_ipi_ops->single(cpu);
142 }
143 
144 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
145 {
146 	int cpu;
147 
148 	/* trigger IPI mask call on each CPU */
149 	for_each_cpu(cpu, mask)
150 		sparc32_ipi_ops->mask_one(cpu);
151 }
152 
153 void smp_resched_interrupt(void)
154 {
155 	irq_enter();
156 	scheduler_ipi();
157 	local_cpu_data().irq_resched_count++;
158 	irq_exit();
159 	/* re-schedule routine called by interrupt return code. */
160 }
161 
162 void smp_call_function_single_interrupt(void)
163 {
164 	irq_enter();
165 	generic_smp_call_function_single_interrupt();
166 	local_cpu_data().irq_call_count++;
167 	irq_exit();
168 }
169 
170 void smp_call_function_interrupt(void)
171 {
172 	irq_enter();
173 	generic_smp_call_function_interrupt();
174 	local_cpu_data().irq_call_count++;
175 	irq_exit();
176 }
177 
178 int setup_profiling_timer(unsigned int multiplier)
179 {
180 	return -EINVAL;
181 }
182 
183 void __init smp_prepare_cpus(unsigned int max_cpus)
184 {
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 __cpu_up(unsigned int cpu, struct task_struct *tidle)
260 {
261 	int ret=0;
262 
263 	switch(sparc_cpu_model) {
264 	case sun4m:
265 		ret = smp4m_boot_one_cpu(cpu, tidle);
266 		break;
267 	case sun4d:
268 		ret = smp4d_boot_one_cpu(cpu, tidle);
269 		break;
270 	case sparc_leon:
271 		ret = leon_boot_one_cpu(cpu, tidle);
272 		break;
273 	case sun4e:
274 		printk("SUN4E\n");
275 		BUG();
276 		break;
277 	case sun4u:
278 		printk("SUN4U\n");
279 		BUG();
280 		break;
281 	default:
282 		printk("UNKNOWN!\n");
283 		BUG();
284 		break;
285 	}
286 
287 	if (!ret) {
288 		cpumask_set_cpu(cpu, &smp_commenced_mask);
289 		while (!cpu_online(cpu))
290 			mb();
291 	}
292 	return ret;
293 }
294 
295 static void arch_cpu_pre_starting(void *arg)
296 {
297 	local_ops->cache_all();
298 	local_ops->tlb_all();
299 
300 	switch(sparc_cpu_model) {
301 	case sun4m:
302 		sun4m_cpu_pre_starting(arg);
303 		break;
304 	case sun4d:
305 		sun4d_cpu_pre_starting(arg);
306 		break;
307 	case sparc_leon:
308 		leon_cpu_pre_starting(arg);
309 		break;
310 	default:
311 		BUG();
312 	}
313 }
314 
315 static void arch_cpu_pre_online(void *arg)
316 {
317 	unsigned int cpuid = hard_smp_processor_id();
318 
319 	register_percpu_ce(cpuid);
320 
321 	calibrate_delay();
322 	smp_store_cpu_info(cpuid);
323 
324 	local_ops->cache_all();
325 	local_ops->tlb_all();
326 
327 	switch(sparc_cpu_model) {
328 	case sun4m:
329 		sun4m_cpu_pre_online(arg);
330 		break;
331 	case sun4d:
332 		sun4d_cpu_pre_online(arg);
333 		break;
334 	case sparc_leon:
335 		leon_cpu_pre_online(arg);
336 		break;
337 	default:
338 		BUG();
339 	}
340 }
341 
342 static void sparc_start_secondary(void *arg)
343 {
344 	unsigned int cpu;
345 
346 	/*
347 	 * SMP booting is extremely fragile in some architectures. So run
348 	 * the cpu initialization code first before anything else.
349 	 */
350 	arch_cpu_pre_starting(arg);
351 
352 	preempt_disable();
353 	cpu = smp_processor_id();
354 
355 	/* Invoke the CPU_STARTING notifier callbacks */
356 	notify_cpu_starting(cpu);
357 
358 	arch_cpu_pre_online(arg);
359 
360 	/* Set the CPU in the cpu_online_mask */
361 	set_cpu_online(cpu, true);
362 
363 	/* Enable local interrupts now */
364 	local_irq_enable();
365 
366 	wmb();
367 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
368 
369 	/* We should never reach here! */
370 	BUG();
371 }
372 
373 void smp_callin(void)
374 {
375 	sparc_start_secondary(NULL);
376 }
377 
378 void smp_bogo(struct seq_file *m)
379 {
380 	int i;
381 
382 	for_each_online_cpu(i) {
383 		seq_printf(m,
384 			   "Cpu%dBogo\t: %lu.%02lu\n",
385 			   i,
386 			   cpu_data(i).udelay_val/(500000/HZ),
387 			   (cpu_data(i).udelay_val/(5000/HZ))%100);
388 	}
389 }
390 
391 void smp_info(struct seq_file *m)
392 {
393 	int i;
394 
395 	seq_printf(m, "State:\n");
396 	for_each_online_cpu(i)
397 		seq_printf(m, "CPU%d\t\t: online\n", i);
398 }
399