1 // SPDX-License-Identifier: GPL-2.0
2 /* smp.c: Sparc SMP support.
3 *
4 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
5 * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
6 * Copyright (C) 2004 Keith M Wesolowski (wesolows@foobazco.org)
7 */
8
9 #include <asm/head.h>
10
11 #include <linux/kernel.h>
12 #include <linux/sched.h>
13 #include <linux/threads.h>
14 #include <linux/smp.h>
15 #include <linux/interrupt.h>
16 #include <linux/kernel_stat.h>
17 #include <linux/init.h>
18 #include <linux/spinlock.h>
19 #include <linux/mm.h>
20 #include <linux/fs.h>
21 #include <linux/seq_file.h>
22 #include <linux/cache.h>
23 #include <linux/delay.h>
24 #include <linux/profile.h>
25 #include <linux/cpu.h>
26
27 #include <asm/ptrace.h>
28 #include <linux/atomic.h>
29
30 #include <asm/irq.h>
31 #include <asm/page.h>
32 #include <asm/oplib.h>
33 #include <asm/cacheflush.h>
34 #include <asm/tlbflush.h>
35 #include <asm/cpudata.h>
36 #include <asm/timer.h>
37 #include <asm/leon.h>
38
39 #include "kernel.h"
40 #include "irq.h"
41
42 volatile unsigned long cpu_callin_map[NR_CPUS] = {0,};
43
44 cpumask_t smp_commenced_mask = CPU_MASK_NONE;
45
46 const struct sparc32_ipi_ops *sparc32_ipi_ops;
47
48 /* The only guaranteed locking primitive available on all Sparc
49 * processors is 'ldstub [%reg + immediate], %dest_reg' which atomically
50 * places the current byte at the effective address into dest_reg and
51 * places 0xff there afterwards. Pretty lame locking primitive
52 * compared to the Alpha and the Intel no? Most Sparcs have 'swap'
53 * instruction which is much better...
54 */
55
smp_store_cpu_info(int id)56 void smp_store_cpu_info(int id)
57 {
58 int cpu_node;
59 int mid;
60
61 cpu_data(id).udelay_val = loops_per_jiffy;
62
63 cpu_find_by_mid(id, &cpu_node);
64 cpu_data(id).clock_tick = prom_getintdefault(cpu_node,
65 "clock-frequency", 0);
66 cpu_data(id).prom_node = cpu_node;
67 mid = cpu_get_hwmid(cpu_node);
68
69 if (mid < 0) {
70 printk(KERN_NOTICE "No MID found for CPU%d at node 0x%08x", id, cpu_node);
71 mid = 0;
72 }
73 cpu_data(id).mid = mid;
74 }
75
smp_cpus_done(unsigned int max_cpus)76 void __init smp_cpus_done(unsigned int max_cpus)
77 {
78 unsigned long bogosum = 0;
79 int cpu, num = 0;
80
81 for_each_online_cpu(cpu) {
82 num++;
83 bogosum += cpu_data(cpu).udelay_val;
84 }
85
86 printk("Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
87 num, bogosum/(500000/HZ),
88 (bogosum/(5000/HZ))%100);
89
90 switch(sparc_cpu_model) {
91 case sun4m:
92 smp4m_smp_done();
93 break;
94 case sun4d:
95 smp4d_smp_done();
96 break;
97 case sparc_leon:
98 leon_smp_done();
99 break;
100 case sun4e:
101 printk("SUN4E\n");
102 BUG();
103 break;
104 case sun4u:
105 printk("SUN4U\n");
106 BUG();
107 break;
108 default:
109 printk("UNKNOWN!\n");
110 BUG();
111 break;
112 }
113 }
114
cpu_panic(void)115 void cpu_panic(void)
116 {
117 printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
118 panic("SMP bolixed\n");
119 }
120
121 struct linux_prom_registers smp_penguin_ctable = { 0 };
122
smp_send_reschedule(int cpu)123 void smp_send_reschedule(int cpu)
124 {
125 /*
126 * CPU model dependent way of implementing IPI generation targeting
127 * a single CPU. The trap handler needs only to do trap entry/return
128 * to call schedule.
129 */
130 sparc32_ipi_ops->resched(cpu);
131 }
132
smp_send_stop(void)133 void smp_send_stop(void)
134 {
135 }
136
arch_send_call_function_single_ipi(int cpu)137 void arch_send_call_function_single_ipi(int cpu)
138 {
139 /* trigger one IPI single call on one CPU */
140 sparc32_ipi_ops->single(cpu);
141 }
142
arch_send_call_function_ipi_mask(const struct cpumask * mask)143 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
144 {
145 int cpu;
146
147 /* trigger IPI mask call on each CPU */
148 for_each_cpu(cpu, mask)
149 sparc32_ipi_ops->mask_one(cpu);
150 }
151
smp_resched_interrupt(void)152 void smp_resched_interrupt(void)
153 {
154 irq_enter();
155 scheduler_ipi();
156 local_cpu_data().irq_resched_count++;
157 irq_exit();
158 /* re-schedule routine called by interrupt return code. */
159 }
160
smp_call_function_single_interrupt(void)161 void smp_call_function_single_interrupt(void)
162 {
163 irq_enter();
164 generic_smp_call_function_single_interrupt();
165 local_cpu_data().irq_call_count++;
166 irq_exit();
167 }
168
smp_call_function_interrupt(void)169 void smp_call_function_interrupt(void)
170 {
171 irq_enter();
172 generic_smp_call_function_interrupt();
173 local_cpu_data().irq_call_count++;
174 irq_exit();
175 }
176
smp_prepare_cpus(unsigned int max_cpus)177 void __init smp_prepare_cpus(unsigned int max_cpus)
178 {
179 int i, cpuid, extra;
180
181 printk("Entering SMP Mode...\n");
182
183 extra = 0;
184 for (i = 0; !cpu_find_by_instance(i, NULL, &cpuid); i++) {
185 if (cpuid >= NR_CPUS)
186 extra++;
187 }
188 /* i = number of cpus */
189 if (extra && max_cpus > i - extra)
190 printk("Warning: NR_CPUS is too low to start all cpus\n");
191
192 smp_store_cpu_info(boot_cpu_id);
193
194 switch(sparc_cpu_model) {
195 case sun4m:
196 smp4m_boot_cpus();
197 break;
198 case sun4d:
199 smp4d_boot_cpus();
200 break;
201 case sparc_leon:
202 leon_boot_cpus();
203 break;
204 case sun4e:
205 printk("SUN4E\n");
206 BUG();
207 break;
208 case sun4u:
209 printk("SUN4U\n");
210 BUG();
211 break;
212 default:
213 printk("UNKNOWN!\n");
214 BUG();
215 break;
216 }
217 }
218
219 /* Set this up early so that things like the scheduler can init
220 * properly. We use the same cpu mask for both the present and
221 * possible cpu map.
222 */
smp_setup_cpu_possible_map(void)223 void __init smp_setup_cpu_possible_map(void)
224 {
225 int instance, mid;
226
227 instance = 0;
228 while (!cpu_find_by_instance(instance, NULL, &mid)) {
229 if (mid < NR_CPUS) {
230 set_cpu_possible(mid, true);
231 set_cpu_present(mid, true);
232 }
233 instance++;
234 }
235 }
236
smp_prepare_boot_cpu(void)237 void __init smp_prepare_boot_cpu(void)
238 {
239 int cpuid = hard_smp_processor_id();
240
241 if (cpuid >= NR_CPUS) {
242 prom_printf("Serious problem, boot cpu id >= NR_CPUS\n");
243 prom_halt();
244 }
245 if (cpuid != 0)
246 printk("boot cpu id != 0, this could work but is untested\n");
247
248 current_thread_info()->cpu = cpuid;
249 set_cpu_online(cpuid, true);
250 set_cpu_possible(cpuid, true);
251 }
252
__cpu_up(unsigned int cpu,struct task_struct * tidle)253 int __cpu_up(unsigned int cpu, struct task_struct *tidle)
254 {
255 int ret=0;
256
257 switch(sparc_cpu_model) {
258 case sun4m:
259 ret = smp4m_boot_one_cpu(cpu, tidle);
260 break;
261 case sun4d:
262 ret = smp4d_boot_one_cpu(cpu, tidle);
263 break;
264 case sparc_leon:
265 ret = leon_boot_one_cpu(cpu, tidle);
266 break;
267 case sun4e:
268 printk("SUN4E\n");
269 BUG();
270 break;
271 case sun4u:
272 printk("SUN4U\n");
273 BUG();
274 break;
275 default:
276 printk("UNKNOWN!\n");
277 BUG();
278 break;
279 }
280
281 if (!ret) {
282 cpumask_set_cpu(cpu, &smp_commenced_mask);
283 while (!cpu_online(cpu))
284 mb();
285 }
286 return ret;
287 }
288
arch_cpu_pre_starting(void * arg)289 static void arch_cpu_pre_starting(void *arg)
290 {
291 local_ops->cache_all();
292 local_ops->tlb_all();
293
294 switch(sparc_cpu_model) {
295 case sun4m:
296 sun4m_cpu_pre_starting(arg);
297 break;
298 case sun4d:
299 sun4d_cpu_pre_starting(arg);
300 break;
301 case sparc_leon:
302 leon_cpu_pre_starting(arg);
303 break;
304 default:
305 BUG();
306 }
307 }
308
arch_cpu_pre_online(void * arg)309 static void arch_cpu_pre_online(void *arg)
310 {
311 unsigned int cpuid = hard_smp_processor_id();
312
313 register_percpu_ce(cpuid);
314
315 calibrate_delay();
316 smp_store_cpu_info(cpuid);
317
318 local_ops->cache_all();
319 local_ops->tlb_all();
320
321 switch(sparc_cpu_model) {
322 case sun4m:
323 sun4m_cpu_pre_online(arg);
324 break;
325 case sun4d:
326 sun4d_cpu_pre_online(arg);
327 break;
328 case sparc_leon:
329 leon_cpu_pre_online(arg);
330 break;
331 default:
332 BUG();
333 }
334 }
335
sparc_start_secondary(void * arg)336 static void sparc_start_secondary(void *arg)
337 {
338 unsigned int cpu;
339
340 /*
341 * SMP booting is extremely fragile in some architectures. So run
342 * the cpu initialization code first before anything else.
343 */
344 arch_cpu_pre_starting(arg);
345
346 cpu = smp_processor_id();
347
348 notify_cpu_starting(cpu);
349 arch_cpu_pre_online(arg);
350
351 /* Set the CPU in the cpu_online_mask */
352 set_cpu_online(cpu, true);
353
354 /* Enable local interrupts now */
355 local_irq_enable();
356
357 wmb();
358 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
359
360 /* We should never reach here! */
361 BUG();
362 }
363
smp_callin(void)364 void smp_callin(void)
365 {
366 sparc_start_secondary(NULL);
367 }
368
smp_bogo(struct seq_file * m)369 void smp_bogo(struct seq_file *m)
370 {
371 int i;
372
373 for_each_online_cpu(i) {
374 seq_printf(m,
375 "Cpu%dBogo\t: %lu.%02lu\n",
376 i,
377 cpu_data(i).udelay_val/(500000/HZ),
378 (cpu_data(i).udelay_val/(5000/HZ))%100);
379 }
380 }
381
smp_info(struct seq_file * m)382 void smp_info(struct seq_file *m)
383 {
384 int i;
385
386 seq_printf(m, "State:\n");
387 for_each_online_cpu(i)
388 seq_printf(m, "CPU%d\t\t: online\n", i);
389 }
390
