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15#include <linux/spinlock.h>
16#include <linux/sched.h>
17#include <linux/interrupt.h>
18#include <linux/profile.h>
19#include <linux/mm.h>
20#include <linux/cpu.h>
21#include <linux/irq.h>
22#include <linux/atomic.h>
23#include <linux/cpumask.h>
24#include <linux/reboot.h>
25#include <asm/processor.h>
26#include <asm/setup.h>
27#include <asm/mach_desc.h>
28
29#ifndef CONFIG_ARC_HAS_LLSC
30arch_spinlock_t smp_atomic_ops_lock = __ARCH_SPIN_LOCK_UNLOCKED;
31arch_spinlock_t smp_bitops_lock = __ARCH_SPIN_LOCK_UNLOCKED;
32#endif
33
34struct plat_smp_ops plat_smp_ops;
35
36
37struct task_struct *secondary_idle_tsk;
38
39
40void __init smp_prepare_boot_cpu(void)
41{
42}
43
44
45
46
47
48void __init smp_init_cpus(void)
49{
50 unsigned int i;
51
52 for (i = 0; i < NR_CPUS; i++)
53 set_cpu_possible(i, true);
54}
55
56
57void __init smp_prepare_cpus(unsigned int max_cpus)
58{
59 int i;
60
61
62
63
64
65 for (i = 0; i < max_cpus; i++)
66 set_cpu_present(i, true);
67}
68
69void __init smp_cpus_done(unsigned int max_cpus)
70{
71
72}
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91
92void __weak arc_platform_smp_wait_to_boot(int cpu)
93{
94
95
96
97
98 __asm__ __volatile__(
99 "1: \n"
100 " flag 1 \n"
101 " b 1b \n");
102}
103
104const char *arc_platform_smp_cpuinfo(void)
105{
106 return plat_smp_ops.info ? : "";
107}
108
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111
112
113
114void start_kernel_secondary(void)
115{
116 struct mm_struct *mm = &init_mm;
117 unsigned int cpu = smp_processor_id();
118
119
120 setup_processor();
121
122 atomic_inc(&mm->mm_users);
123 atomic_inc(&mm->mm_count);
124 current->active_mm = mm;
125 cpumask_set_cpu(cpu, mm_cpumask(mm));
126
127 notify_cpu_starting(cpu);
128 set_cpu_online(cpu, true);
129
130 pr_info("## CPU%u LIVE ##: Executing Code...\n", cpu);
131
132 if (machine_desc->init_smp)
133 machine_desc->init_smp(cpu);
134
135 arc_local_timer_setup();
136
137 local_irq_enable();
138 preempt_disable();
139 cpu_startup_entry(CPUHP_ONLINE);
140}
141
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150
151
152int __cpu_up(unsigned int cpu, struct task_struct *idle)
153{
154 unsigned long wait_till;
155
156 secondary_idle_tsk = idle;
157
158 pr_info("Idle Task [%d] %p", cpu, idle);
159 pr_info("Trying to bring up CPU%u ...\n", cpu);
160
161 if (plat_smp_ops.cpu_kick)
162 plat_smp_ops.cpu_kick(cpu,
163 (unsigned long)first_lines_of_secondary);
164
165
166 wait_till = jiffies + HZ;
167 while (time_before(jiffies, wait_till)) {
168 if (cpu_online(cpu))
169 break;
170 }
171
172 if (!cpu_online(cpu)) {
173 pr_info("Timeout: CPU%u FAILED to comeup !!!\n", cpu);
174 return -1;
175 }
176
177 secondary_idle_tsk = NULL;
178
179 return 0;
180}
181
182
183
184
185int __init setup_profiling_timer(unsigned int multiplier)
186{
187 return -EINVAL;
188}
189
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191
192
193
194enum ipi_msg_type {
195 IPI_EMPTY = 0,
196 IPI_RESCHEDULE = 1,
197 IPI_CALL_FUNC,
198 IPI_CPU_STOP,
199};
200
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206
207static DEFINE_PER_CPU(unsigned long, ipi_data);
208
209static void ipi_send_msg_one(int cpu, enum ipi_msg_type msg)
210{
211 unsigned long __percpu *ipi_data_ptr = per_cpu_ptr(&ipi_data, cpu);
212 unsigned long old, new;
213 unsigned long flags;
214
215 pr_debug("%d Sending msg [%d] to %d\n", smp_processor_id(), msg, cpu);
216
217 local_irq_save(flags);
218
219
220
221
222
223 do {
224 new = old = ACCESS_ONCE(*ipi_data_ptr);
225 new |= 1U << msg;
226 } while (cmpxchg(ipi_data_ptr, old, new) != old);
227
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234
235
236 if (plat_smp_ops.ipi_send && !old)
237 plat_smp_ops.ipi_send(cpu);
238
239 local_irq_restore(flags);
240}
241
242static void ipi_send_msg(const struct cpumask *callmap, enum ipi_msg_type msg)
243{
244 unsigned int cpu;
245
246 for_each_cpu(cpu, callmap)
247 ipi_send_msg_one(cpu, msg);
248}
249
250void smp_send_reschedule(int cpu)
251{
252 ipi_send_msg_one(cpu, IPI_RESCHEDULE);
253}
254
255void smp_send_stop(void)
256{
257 struct cpumask targets;
258 cpumask_copy(&targets, cpu_online_mask);
259 cpumask_clear_cpu(smp_processor_id(), &targets);
260 ipi_send_msg(&targets, IPI_CPU_STOP);
261}
262
263void arch_send_call_function_single_ipi(int cpu)
264{
265 ipi_send_msg_one(cpu, IPI_CALL_FUNC);
266}
267
268void arch_send_call_function_ipi_mask(const struct cpumask *mask)
269{
270 ipi_send_msg(mask, IPI_CALL_FUNC);
271}
272
273
274
275
276static void ipi_cpu_stop(void)
277{
278 machine_halt();
279}
280
281static inline void __do_IPI(unsigned long msg)
282{
283 switch (msg) {
284 case IPI_RESCHEDULE:
285 scheduler_ipi();
286 break;
287
288 case IPI_CALL_FUNC:
289 generic_smp_call_function_interrupt();
290 break;
291
292 case IPI_CPU_STOP:
293 ipi_cpu_stop();
294 break;
295
296 default:
297 pr_warn("IPI with unexpected msg %ld\n", msg);
298 }
299}
300
301
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303
304
305irqreturn_t do_IPI(int irq, void *dev_id)
306{
307 unsigned long pending;
308
309 pr_debug("IPI [%ld] received on cpu %d\n",
310 *this_cpu_ptr(&ipi_data), smp_processor_id());
311
312 if (plat_smp_ops.ipi_clear)
313 plat_smp_ops.ipi_clear(irq);
314
315
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318
319 pending = xchg(this_cpu_ptr(&ipi_data), 0);
320
321 do {
322 unsigned long msg = __ffs(pending);
323 __do_IPI(msg);
324 pending &= ~(1U << msg);
325 } while (pending);
326
327 return IRQ_HANDLED;
328}
329
330
331
332
333static DEFINE_PER_CPU(int, ipi_dev);
334
335int smp_ipi_irq_setup(int cpu, int irq)
336{
337 int *dev = per_cpu_ptr(&ipi_dev, cpu);
338
339 arc_request_percpu_irq(irq, cpu, do_IPI, "IPI Interrupt", dev);
340
341 return 0;
342}
343