// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2020-2022 Loongson Technology Corporation Limited * * Derived from MIPS: * Copyright (C) 2000, 2001 Kanoj Sarcar * Copyright (C) 2000, 2001 Ralf Baechle * Copyright (C) 2000, 2001 Silicon Graphics, Inc. * Copyright (C) 2000, 2001, 2003 Broadcom Corporation */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include int __cpu_number_map[NR_CPUS]; /* Map physical to logical */ EXPORT_SYMBOL(__cpu_number_map); int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */ EXPORT_SYMBOL(__cpu_logical_map); /* Number of threads (siblings) per CPU core */ int smp_num_siblings = 1; EXPORT_SYMBOL(smp_num_siblings); /* Representing the threads (siblings) of each logical CPU */ cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly; EXPORT_SYMBOL(cpu_sibling_map); /* Representing the core map of multi-core chips of each logical CPU */ cpumask_t cpu_core_map[NR_CPUS] __read_mostly; EXPORT_SYMBOL(cpu_core_map); static DECLARE_COMPLETION(cpu_starting); static DECLARE_COMPLETION(cpu_running); /* * A logcal cpu mask containing only one VPE per core to * reduce the number of IPIs on large MT systems. */ cpumask_t cpu_foreign_map[NR_CPUS] __read_mostly; EXPORT_SYMBOL(cpu_foreign_map); /* representing cpus for which sibling maps can be computed */ static cpumask_t cpu_sibling_setup_map; /* representing cpus for which core maps can be computed */ static cpumask_t cpu_core_setup_map; struct secondary_data cpuboot_data; static DEFINE_PER_CPU(int, cpu_state); enum ipi_msg_type { IPI_RESCHEDULE, IPI_CALL_FUNCTION, }; static const char *ipi_types[NR_IPI] __tracepoint_string = { [IPI_RESCHEDULE] = "Rescheduling interrupts", [IPI_CALL_FUNCTION] = "Function call interrupts", }; void show_ipi_list(struct seq_file *p, int prec) { unsigned int cpu, i; for (i = 0; i < NR_IPI; i++) { seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i, prec >= 4 ? " " : ""); for_each_online_cpu(cpu) seq_printf(p, "%10u ", per_cpu(irq_stat, cpu).ipi_irqs[i]); seq_printf(p, " LoongArch %d %s\n", i + 1, ipi_types[i]); } } /* Send mailbox buffer via Mail_Send */ static void csr_mail_send(uint64_t data, int cpu, int mailbox) { uint64_t val; /* Send high 32 bits */ val = IOCSR_MBUF_SEND_BLOCKING; val |= (IOCSR_MBUF_SEND_BOX_HI(mailbox) << IOCSR_MBUF_SEND_BOX_SHIFT); val |= (cpu << IOCSR_MBUF_SEND_CPU_SHIFT); val |= (data & IOCSR_MBUF_SEND_H32_MASK); iocsr_write64(val, LOONGARCH_IOCSR_MBUF_SEND); /* Send low 32 bits */ val = IOCSR_MBUF_SEND_BLOCKING; val |= (IOCSR_MBUF_SEND_BOX_LO(mailbox) << IOCSR_MBUF_SEND_BOX_SHIFT); val |= (cpu << IOCSR_MBUF_SEND_CPU_SHIFT); val |= (data << IOCSR_MBUF_SEND_BUF_SHIFT); iocsr_write64(val, LOONGARCH_IOCSR_MBUF_SEND); }; static u32 ipi_read_clear(int cpu) { u32 action; /* Load the ipi register to figure out what we're supposed to do */ action = iocsr_read32(LOONGARCH_IOCSR_IPI_STATUS); /* Clear the ipi register to clear the interrupt */ iocsr_write32(action, LOONGARCH_IOCSR_IPI_CLEAR); smp_mb(); return action; } static void ipi_write_action(int cpu, u32 action) { unsigned int irq = 0; while ((irq = ffs(action))) { uint32_t val = IOCSR_IPI_SEND_BLOCKING; val |= (irq - 1); val |= (cpu << IOCSR_IPI_SEND_CPU_SHIFT); iocsr_write32(val, LOONGARCH_IOCSR_IPI_SEND); action &= ~BIT(irq - 1); } } void loongson_send_ipi_single(int cpu, unsigned int action) { ipi_write_action(cpu_logical_map(cpu), (u32)action); } void loongson_send_ipi_mask(const struct cpumask *mask, unsigned int action) { unsigned int i; for_each_cpu(i, mask) ipi_write_action(cpu_logical_map(i), (u32)action); } /* * This function sends a 'reschedule' IPI to another CPU. * it goes straight through and wastes no time serializing * anything. Worst case is that we lose a reschedule ... */ void smp_send_reschedule(int cpu) { loongson_send_ipi_single(cpu, SMP_RESCHEDULE); } EXPORT_SYMBOL_GPL(smp_send_reschedule); irqreturn_t loongson_ipi_interrupt(int irq, void *dev) { unsigned int action; unsigned int cpu = smp_processor_id(); action = ipi_read_clear(cpu_logical_map(cpu)); if (action & SMP_RESCHEDULE) { scheduler_ipi(); per_cpu(irq_stat, cpu).ipi_irqs[IPI_RESCHEDULE]++; } if (action & SMP_CALL_FUNCTION) { generic_smp_call_function_interrupt(); per_cpu(irq_stat, cpu).ipi_irqs[IPI_CALL_FUNCTION]++; } return IRQ_HANDLED; } void __init loongson_smp_setup(void) { cpu_data[0].core = cpu_logical_map(0) % loongson_sysconf.cores_per_package; cpu_data[0].package = cpu_logical_map(0) / loongson_sysconf.cores_per_package; iocsr_write32(0xffffffff, LOONGARCH_IOCSR_IPI_EN); pr_info("Detected %i available CPU(s)\n", loongson_sysconf.nr_cpus); } void __init loongson_prepare_cpus(unsigned int max_cpus) { int i = 0; for (i = 0; i < loongson_sysconf.nr_cpus; i++) { set_cpu_present(i, true); csr_mail_send(0, __cpu_logical_map[i], 0); } per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE; } /* * Setup the PC, SP, and TP of a secondary processor and start it running! */ void loongson_boot_secondary(int cpu, struct task_struct *idle) { unsigned long entry; pr_info("Booting CPU#%d...\n", cpu); entry = __pa_symbol((unsigned long)&smpboot_entry); cpuboot_data.stack = (unsigned long)__KSTK_TOS(idle); cpuboot_data.thread_info = (unsigned long)task_thread_info(idle); csr_mail_send(entry, cpu_logical_map(cpu), 0); loongson_send_ipi_single(cpu, SMP_BOOT_CPU); } /* * SMP init and finish on secondary CPUs */ void loongson_init_secondary(void) { unsigned int cpu = smp_processor_id(); unsigned int imask = ECFGF_IP0 | ECFGF_IP1 | ECFGF_IP2 | ECFGF_IPI | ECFGF_PMC | ECFGF_TIMER; change_csr_ecfg(ECFG0_IM, imask); iocsr_write32(0xffffffff, LOONGARCH_IOCSR_IPI_EN); #ifdef CONFIG_NUMA numa_add_cpu(cpu); #endif per_cpu(cpu_state, cpu) = CPU_ONLINE; cpu_data[cpu].core = cpu_logical_map(cpu) % loongson_sysconf.cores_per_package; cpu_data[cpu].package = cpu_logical_map(cpu) / loongson_sysconf.cores_per_package; } void loongson_smp_finish(void) { local_irq_enable(); iocsr_write64(0, LOONGARCH_IOCSR_MBUF0); pr_info("CPU#%d finished\n", smp_processor_id()); } #ifdef CONFIG_HOTPLUG_CPU int loongson_cpu_disable(void) { unsigned long flags; unsigned int cpu = smp_processor_id(); if (io_master(cpu)) return -EBUSY; #ifdef CONFIG_NUMA numa_remove_cpu(cpu); #endif set_cpu_online(cpu, false); calculate_cpu_foreign_map(); local_irq_save(flags); irq_migrate_all_off_this_cpu(); clear_csr_ecfg(ECFG0_IM); local_irq_restore(flags); local_flush_tlb_all(); return 0; } void loongson_cpu_die(unsigned int cpu) { while (per_cpu(cpu_state, cpu) != CPU_DEAD) cpu_relax(); mb(); } void play_dead(void) { register uint64_t addr; register void (*init_fn)(void); idle_task_exit(); local_irq_enable(); set_csr_ecfg(ECFGF_IPI); __this_cpu_write(cpu_state, CPU_DEAD); __smp_mb(); do { __asm__ __volatile__("idle 0\n\t"); addr = iocsr_read64(LOONGARCH_IOCSR_MBUF0); } while (addr == 0); init_fn = (void *)TO_CACHE(addr); iocsr_write32(0xffffffff, LOONGARCH_IOCSR_IPI_CLEAR); init_fn(); unreachable(); } #endif /* * Power management */ #ifdef CONFIG_PM static int loongson_ipi_suspend(void) { return 0; } static void loongson_ipi_resume(void) { iocsr_write32(0xffffffff, LOONGARCH_IOCSR_IPI_EN); } static struct syscore_ops loongson_ipi_syscore_ops = { .resume = loongson_ipi_resume, .suspend = loongson_ipi_suspend, }; /* * Enable boot cpu ipi before enabling nonboot cpus * during syscore_resume. */ static int __init ipi_pm_init(void) { register_syscore_ops(&loongson_ipi_syscore_ops); return 0; } core_initcall(ipi_pm_init); #endif static inline void set_cpu_sibling_map(int cpu) { int i; cpumask_set_cpu(cpu, &cpu_sibling_setup_map); if (smp_num_siblings <= 1) cpumask_set_cpu(cpu, &cpu_sibling_map[cpu]); else { for_each_cpu(i, &cpu_sibling_setup_map) { if (cpus_are_siblings(cpu, i)) { cpumask_set_cpu(i, &cpu_sibling_map[cpu]); cpumask_set_cpu(cpu, &cpu_sibling_map[i]); } } } } static inline void set_cpu_core_map(int cpu) { int i; cpumask_set_cpu(cpu, &cpu_core_setup_map); for_each_cpu(i, &cpu_core_setup_map) { if (cpu_data[cpu].package == cpu_data[i].package) { cpumask_set_cpu(i, &cpu_core_map[cpu]); cpumask_set_cpu(cpu, &cpu_core_map[i]); } } } /* * Calculate a new cpu_foreign_map mask whenever a * new cpu appears or disappears. */ void calculate_cpu_foreign_map(void) { int i, k, core_present; cpumask_t temp_foreign_map; /* Re-calculate the mask */ cpumask_clear(&temp_foreign_map); for_each_online_cpu(i) { core_present = 0; for_each_cpu(k, &temp_foreign_map) if (cpus_are_siblings(i, k)) core_present = 1; if (!core_present) cpumask_set_cpu(i, &temp_foreign_map); } for_each_online_cpu(i) cpumask_andnot(&cpu_foreign_map[i], &temp_foreign_map, &cpu_sibling_map[i]); } /* Preload SMP state for boot cpu */ void smp_prepare_boot_cpu(void) { unsigned int cpu, node, rr_node; set_cpu_possible(0, true); set_cpu_online(0, true); set_my_cpu_offset(per_cpu_offset(0)); rr_node = first_node(node_online_map); for_each_possible_cpu(cpu) { node = early_cpu_to_node(cpu); /* * The mapping between present cpus and nodes has been * built during MADT and SRAT parsing. * * If possible cpus = present cpus here, early_cpu_to_node * will return valid node. * * If possible cpus > present cpus here (e.g. some possible * cpus will be added by cpu-hotplug later), for possible but * not present cpus, early_cpu_to_node will return NUMA_NO_NODE, * and we just map them to online nodes in round-robin way. * Once hotplugged, new correct mapping will be built for them. */ if (node != NUMA_NO_NODE) set_cpu_numa_node(cpu, node); else { set_cpu_numa_node(cpu, rr_node); rr_node = next_node_in(rr_node, node_online_map); } } } /* called from main before smp_init() */ void __init smp_prepare_cpus(unsigned int max_cpus) { init_new_context(current, &init_mm); current_thread_info()->cpu = 0; loongson_prepare_cpus(max_cpus); set_cpu_sibling_map(0); set_cpu_core_map(0); calculate_cpu_foreign_map(); #ifndef CONFIG_HOTPLUG_CPU init_cpu_present(cpu_possible_mask); #endif } int __cpu_up(unsigned int cpu, struct task_struct *tidle) { loongson_boot_secondary(cpu, tidle); /* Wait for CPU to start and be ready to sync counters */ if (!wait_for_completion_timeout(&cpu_starting, msecs_to_jiffies(5000))) { pr_crit("CPU%u: failed to start\n", cpu); return -EIO; } /* Wait for CPU to finish startup & mark itself online before return */ wait_for_completion(&cpu_running); return 0; } /* * First C code run on the secondary CPUs after being started up by * the master. */ asmlinkage void start_secondary(void) { unsigned int cpu; sync_counter(); cpu = smp_processor_id(); set_my_cpu_offset(per_cpu_offset(cpu)); cpu_probe(); constant_clockevent_init(); loongson_init_secondary(); set_cpu_sibling_map(cpu); set_cpu_core_map(cpu); notify_cpu_starting(cpu); /* Notify boot CPU that we're starting */ complete(&cpu_starting); /* The CPU is running, now mark it online */ set_cpu_online(cpu, true); calculate_cpu_foreign_map(); /* * Notify boot CPU that we're up & online and it can safely return * from __cpu_up() */ complete(&cpu_running); /* * irq will be enabled in loongson_smp_finish(), enabling it too * early is dangerous. */ WARN_ON_ONCE(!irqs_disabled()); loongson_smp_finish(); cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); } void __init smp_cpus_done(unsigned int max_cpus) { } static void stop_this_cpu(void *dummy) { set_cpu_online(smp_processor_id(), false); calculate_cpu_foreign_map(); local_irq_disable(); while (true); } void smp_send_stop(void) { smp_call_function(stop_this_cpu, NULL, 0); } int setup_profiling_timer(unsigned int multiplier) { return 0; } static void flush_tlb_all_ipi(void *info) { local_flush_tlb_all(); } void flush_tlb_all(void) { on_each_cpu(flush_tlb_all_ipi, NULL, 1); } static void flush_tlb_mm_ipi(void *mm) { local_flush_tlb_mm((struct mm_struct *)mm); } void flush_tlb_mm(struct mm_struct *mm) { if (atomic_read(&mm->mm_users) == 0) return; /* happens as a result of exit_mmap() */ preempt_disable(); if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) { on_each_cpu_mask(mm_cpumask(mm), flush_tlb_mm_ipi, mm, 1); } else { unsigned int cpu; for_each_online_cpu(cpu) { if (cpu != smp_processor_id() && cpu_context(cpu, mm)) cpu_context(cpu, mm) = 0; } local_flush_tlb_mm(mm); } preempt_enable(); } struct flush_tlb_data { struct vm_area_struct *vma; unsigned long addr1; unsigned long addr2; }; static void flush_tlb_range_ipi(void *info) { struct flush_tlb_data *fd = info; local_flush_tlb_range(fd->vma, fd->addr1, fd->addr2); } void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { struct mm_struct *mm = vma->vm_mm; preempt_disable(); if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) { struct flush_tlb_data fd = { .vma = vma, .addr1 = start, .addr2 = end, }; on_each_cpu_mask(mm_cpumask(mm), flush_tlb_range_ipi, &fd, 1); } else { unsigned int cpu; for_each_online_cpu(cpu) { if (cpu != smp_processor_id() && cpu_context(cpu, mm)) cpu_context(cpu, mm) = 0; } local_flush_tlb_range(vma, start, end); } preempt_enable(); } static void flush_tlb_kernel_range_ipi(void *info) { struct flush_tlb_data *fd = info; local_flush_tlb_kernel_range(fd->addr1, fd->addr2); } void flush_tlb_kernel_range(unsigned long start, unsigned long end) { struct flush_tlb_data fd = { .addr1 = start, .addr2 = end, }; on_each_cpu(flush_tlb_kernel_range_ipi, &fd, 1); } static void flush_tlb_page_ipi(void *info) { struct flush_tlb_data *fd = info; local_flush_tlb_page(fd->vma, fd->addr1); } void flush_tlb_page(struct vm_area_struct *vma, unsigned long page) { preempt_disable(); if ((atomic_read(&vma->vm_mm->mm_users) != 1) || (current->mm != vma->vm_mm)) { struct flush_tlb_data fd = { .vma = vma, .addr1 = page, }; on_each_cpu_mask(mm_cpumask(vma->vm_mm), flush_tlb_page_ipi, &fd, 1); } else { unsigned int cpu; for_each_online_cpu(cpu) { if (cpu != smp_processor_id() && cpu_context(cpu, vma->vm_mm)) cpu_context(cpu, vma->vm_mm) = 0; } local_flush_tlb_page(vma, page); } preempt_enable(); } EXPORT_SYMBOL(flush_tlb_page); static void flush_tlb_one_ipi(void *info) { unsigned long vaddr = (unsigned long) info; local_flush_tlb_one(vaddr); } void flush_tlb_one(unsigned long vaddr) { on_each_cpu(flush_tlb_one_ipi, (void *)vaddr, 1); } EXPORT_SYMBOL(flush_tlb_one);