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>
20 #include <asm/cpuinfo.h>
21 #include <asm/mmu_context.h>
22 #include <asm/tlbflush.h>
23 #include <asm/cacheflush.h>
26 static void (*smp_cross_call)(const struct cpumask *, unsigned int);
28 unsigned long secondary_release = -1;
29 struct thread_info *secondary_thread_info;
38 static DEFINE_SPINLOCK(boot_lock);
40 static void boot_secondary(unsigned int cpu, struct task_struct *idle)
43 * set synchronisation state between this boot processor
44 * and the secondary one
46 spin_lock(&boot_lock);
48 secondary_release = cpu;
49 smp_cross_call(cpumask_of(cpu), IPI_WAKEUP);
52 * now the secondary core is starting up let it run its
53 * calibrations, then wait for it to finish
55 spin_unlock(&boot_lock);
58 void __init smp_prepare_boot_cpu(void)
62 void __init smp_init_cpus(void)
64 struct device_node *cpu;
67 for_each_of_cpu_node(cpu) {
68 cpu_id = of_get_cpu_hwid(cpu, 0);
70 set_cpu_possible(cpu_id, true);
74 void __init smp_prepare_cpus(unsigned int max_cpus)
79 * Initialise the present map, which describes the set of CPUs
80 * actually populated at the present time.
82 for_each_possible_cpu(cpu) {
84 set_cpu_present(cpu, true);
88 void __init smp_cpus_done(unsigned int max_cpus)
92 static DECLARE_COMPLETION(cpu_running);
94 int __cpu_up(unsigned int cpu, struct task_struct *idle)
96 if (smp_cross_call == NULL) {
97 pr_warn("CPU%u: failed to start, IPI controller missing",
102 secondary_thread_info = task_thread_info(idle);
103 current_pgd[cpu] = init_mm.pgd;
105 boot_secondary(cpu, idle);
106 if (!wait_for_completion_timeout(&cpu_running,
107 msecs_to_jiffies(1000))) {
108 pr_crit("CPU%u: failed to start\n", cpu);
111 synchronise_count_master(cpu);
116 asmlinkage __init void secondary_start_kernel(void)
118 struct mm_struct *mm = &init_mm;
119 unsigned int cpu = smp_processor_id();
121 * All kernel threads share the same mm context; grab a
122 * reference and switch to it.
125 current->active_mm = mm;
126 cpumask_set_cpu(cpu, mm_cpumask(mm));
128 pr_info("CPU%u: Booted secondary processor\n", cpu);
131 openrisc_clockevent_init();
133 notify_cpu_starting(cpu);
136 * OK, now it's safe to let the boot CPU continue
138 complete(&cpu_running);
140 synchronise_count_slave(cpu);
141 set_cpu_online(cpu, true);
145 * OK, it's off to the idle thread for us
147 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
150 void handle_IPI(unsigned int ipi_msg)
152 unsigned int cpu = smp_processor_id();
163 generic_smp_call_function_interrupt();
166 case IPI_CALL_FUNC_SINGLE:
167 generic_smp_call_function_single_interrupt();
171 WARN(1, "CPU%u: Unknown IPI message 0x%x\n", cpu, ipi_msg);
176 void arch_smp_send_reschedule(int cpu)
178 smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE);
181 static void stop_this_cpu(void *dummy)
183 /* Remove this CPU */
184 set_cpu_online(smp_processor_id(), false);
188 if (mfspr(SPR_UPR) & SPR_UPR_PMP)
189 mtspr(SPR_PMR, mfspr(SPR_PMR) | SPR_PMR_DME);
190 /* If that didn't work, infinite loop */
195 void smp_send_stop(void)
197 smp_call_function(stop_this_cpu, NULL, 0);
200 void __init set_smp_cross_call(void (*fn)(const struct cpumask *, unsigned int))
205 void arch_send_call_function_single_ipi(int cpu)
207 smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
210 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
212 smp_cross_call(mask, IPI_CALL_FUNC);
215 /* TLB flush operations - Performed on each CPU*/
216 static inline void ipi_flush_tlb_all(void *ignored)
218 local_flush_tlb_all();
221 static inline void ipi_flush_tlb_mm(void *info)
223 struct mm_struct *mm = (struct mm_struct *)info;
225 local_flush_tlb_mm(mm);
228 static void smp_flush_tlb_mm(struct cpumask *cmask, struct mm_struct *mm)
232 if (cpumask_empty(cmask))
237 if (cpumask_any_but(cmask, cpuid) >= nr_cpu_ids) {
238 /* local cpu is the only cpu present in cpumask */
239 local_flush_tlb_mm(mm);
241 on_each_cpu_mask(cmask, ipi_flush_tlb_mm, mm, 1);
246 struct flush_tlb_data {
251 static inline void ipi_flush_tlb_page(void *info)
253 struct flush_tlb_data *fd = (struct flush_tlb_data *)info;
255 local_flush_tlb_page(NULL, fd->addr1);
258 static inline void ipi_flush_tlb_range(void *info)
260 struct flush_tlb_data *fd = (struct flush_tlb_data *)info;
262 local_flush_tlb_range(NULL, fd->addr1, fd->addr2);
265 static void smp_flush_tlb_range(const struct cpumask *cmask, unsigned long start,
270 if (cpumask_empty(cmask))
275 if (cpumask_any_but(cmask, cpuid) >= nr_cpu_ids) {
276 /* local cpu is the only cpu present in cpumask */
277 if ((end - start) <= PAGE_SIZE)
278 local_flush_tlb_page(NULL, start);
280 local_flush_tlb_range(NULL, start, end);
282 struct flush_tlb_data fd;
287 if ((end - start) <= PAGE_SIZE)
288 on_each_cpu_mask(cmask, ipi_flush_tlb_page, &fd, 1);
290 on_each_cpu_mask(cmask, ipi_flush_tlb_range, &fd, 1);
295 void flush_tlb_all(void)
297 on_each_cpu(ipi_flush_tlb_all, NULL, 1);
300 void flush_tlb_mm(struct mm_struct *mm)
302 smp_flush_tlb_mm(mm_cpumask(mm), mm);
305 void flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr)
307 smp_flush_tlb_range(mm_cpumask(vma->vm_mm), uaddr, uaddr + PAGE_SIZE);
310 void flush_tlb_range(struct vm_area_struct *vma,
311 unsigned long start, unsigned long end)
313 const struct cpumask *cmask = vma ? mm_cpumask(vma->vm_mm)
315 smp_flush_tlb_range(cmask, start, end);
318 /* Instruction cache invalidate - performed on each cpu */
319 static void ipi_icache_page_inv(void *arg)
321 struct page *page = arg;
323 local_icache_page_inv(page);
326 void smp_icache_page_inv(struct page *page)
328 on_each_cpu(ipi_icache_page_inv, page, 1);
330 EXPORT_SYMBOL(smp_icache_page_inv);