2 * Copyright (C) 2014 Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
3 * Copyright (C) 2017 Stafford Horne <shorne@gmail.com>
5 * Based on arm64 and arc implementations
6 * Copyright (C) 2013 ARM Ltd.
7 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
9 * This file is licensed under the terms of the GNU General Public License
10 * version 2. This program is licensed "as is" without any warranty of any
11 * kind, whether express or implied.
14 #include <linux/smp.h>
15 #include <linux/cpu.h>
16 #include <linux/sched.h>
17 #include <linux/sched/mm.h>
18 #include <linux/irq.h>
19 #include <asm/cpuinfo.h>
20 #include <asm/mmu_context.h>
21 #include <asm/tlbflush.h>
22 #include <asm/cacheflush.h>
25 static void (*smp_cross_call)(const struct cpumask *, unsigned int);
27 unsigned long secondary_release = -1;
28 struct thread_info *secondary_thread_info;
37 static DEFINE_SPINLOCK(boot_lock);
39 static void boot_secondary(unsigned int cpu, struct task_struct *idle)
42 * set synchronisation state between this boot processor
43 * and the secondary one
45 spin_lock(&boot_lock);
47 secondary_release = cpu;
48 smp_cross_call(cpumask_of(cpu), IPI_WAKEUP);
51 * now the secondary core is starting up let it run its
52 * calibrations, then wait for it to finish
54 spin_unlock(&boot_lock);
57 void __init smp_prepare_boot_cpu(void)
61 void __init smp_init_cpus(void)
65 for (i = 0; i < NR_CPUS; i++)
66 set_cpu_possible(i, true);
69 void __init smp_prepare_cpus(unsigned int max_cpus)
74 * Initialise the present map, which describes the set of CPUs
75 * actually populated at the present time.
77 for (i = 0; i < max_cpus; i++)
78 set_cpu_present(i, true);
81 void __init smp_cpus_done(unsigned int max_cpus)
85 static DECLARE_COMPLETION(cpu_running);
87 int __cpu_up(unsigned int cpu, struct task_struct *idle)
89 if (smp_cross_call == NULL) {
90 pr_warn("CPU%u: failed to start, IPI controller missing",
95 secondary_thread_info = task_thread_info(idle);
96 current_pgd[cpu] = init_mm.pgd;
98 boot_secondary(cpu, idle);
99 if (!wait_for_completion_timeout(&cpu_running,
100 msecs_to_jiffies(1000))) {
101 pr_crit("CPU%u: failed to start\n", cpu);
104 synchronise_count_master(cpu);
109 asmlinkage __init void secondary_start_kernel(void)
111 struct mm_struct *mm = &init_mm;
112 unsigned int cpu = smp_processor_id();
114 * All kernel threads share the same mm context; grab a
115 * reference and switch to it.
118 current->active_mm = mm;
119 cpumask_set_cpu(cpu, mm_cpumask(mm));
121 pr_info("CPU%u: Booted secondary processor\n", cpu);
124 openrisc_clockevent_init();
126 notify_cpu_starting(cpu);
129 * OK, now it's safe to let the boot CPU continue
131 complete(&cpu_running);
133 synchronise_count_slave(cpu);
134 set_cpu_online(cpu, true);
138 * OK, it's off to the idle thread for us
140 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
143 void handle_IPI(unsigned int ipi_msg)
145 unsigned int cpu = smp_processor_id();
156 generic_smp_call_function_interrupt();
159 case IPI_CALL_FUNC_SINGLE:
160 generic_smp_call_function_single_interrupt();
164 WARN(1, "CPU%u: Unknown IPI message 0x%x\n", cpu, ipi_msg);
169 void smp_send_reschedule(int cpu)
171 smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE);
174 static void stop_this_cpu(void *dummy)
176 /* Remove this CPU */
177 set_cpu_online(smp_processor_id(), false);
181 if (mfspr(SPR_UPR) & SPR_UPR_PMP)
182 mtspr(SPR_PMR, mfspr(SPR_PMR) | SPR_PMR_DME);
183 /* If that didn't work, infinite loop */
188 void smp_send_stop(void)
190 smp_call_function(stop_this_cpu, NULL, 0);
193 /* not supported, yet */
194 int setup_profiling_timer(unsigned int multiplier)
199 void __init set_smp_cross_call(void (*fn)(const struct cpumask *, unsigned int))
204 void arch_send_call_function_single_ipi(int cpu)
206 smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
209 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
211 smp_cross_call(mask, IPI_CALL_FUNC);
214 /* TLB flush operations - Performed on each CPU*/
215 static inline void ipi_flush_tlb_all(void *ignored)
217 local_flush_tlb_all();
220 static inline void ipi_flush_tlb_mm(void *info)
222 struct mm_struct *mm = (struct mm_struct *)info;
224 local_flush_tlb_mm(mm);
227 static void smp_flush_tlb_mm(struct cpumask *cmask, struct mm_struct *mm)
231 if (cpumask_empty(cmask))
236 if (cpumask_any_but(cmask, cpuid) >= nr_cpu_ids) {
237 /* local cpu is the only cpu present in cpumask */
238 local_flush_tlb_mm(mm);
240 on_each_cpu_mask(cmask, ipi_flush_tlb_mm, mm, 1);
245 struct flush_tlb_data {
250 static inline void ipi_flush_tlb_page(void *info)
252 struct flush_tlb_data *fd = (struct flush_tlb_data *)info;
254 local_flush_tlb_page(NULL, fd->addr1);
257 static inline void ipi_flush_tlb_range(void *info)
259 struct flush_tlb_data *fd = (struct flush_tlb_data *)info;
261 local_flush_tlb_range(NULL, fd->addr1, fd->addr2);
264 static void smp_flush_tlb_range(const struct cpumask *cmask, unsigned long start,
269 if (cpumask_empty(cmask))
274 if (cpumask_any_but(cmask, cpuid) >= nr_cpu_ids) {
275 /* local cpu is the only cpu present in cpumask */
276 if ((end - start) <= PAGE_SIZE)
277 local_flush_tlb_page(NULL, start);
279 local_flush_tlb_range(NULL, start, end);
281 struct flush_tlb_data fd;
286 if ((end - start) <= PAGE_SIZE)
287 on_each_cpu_mask(cmask, ipi_flush_tlb_page, &fd, 1);
289 on_each_cpu_mask(cmask, ipi_flush_tlb_range, &fd, 1);
294 void flush_tlb_all(void)
296 on_each_cpu(ipi_flush_tlb_all, NULL, 1);
299 void flush_tlb_mm(struct mm_struct *mm)
301 smp_flush_tlb_mm(mm_cpumask(mm), mm);
304 void flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr)
306 smp_flush_tlb_range(mm_cpumask(vma->vm_mm), uaddr, uaddr + PAGE_SIZE);
309 void flush_tlb_range(struct vm_area_struct *vma,
310 unsigned long start, unsigned long end)
312 const struct cpumask *cmask = vma ? mm_cpumask(vma->vm_mm)
314 smp_flush_tlb_range(cmask, start, end);
317 /* Instruction cache invalidate - performed on each cpu */
318 static void ipi_icache_page_inv(void *arg)
320 struct page *page = arg;
322 local_icache_page_inv(page);
325 void smp_icache_page_inv(struct page *page)
327 on_each_cpu(ipi_icache_page_inv, page, 1);
329 EXPORT_SYMBOL(smp_icache_page_inv);