diff options
Diffstat (limited to 'arch/mips/kernel/smp.c')
| -rw-r--r-- | arch/mips/kernel/smp.c | 740 |
1 files changed, 740 insertions, 0 deletions
diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c new file mode 100644 index 0000000000..81f6c4f8fb --- /dev/null +++ b/arch/mips/kernel/smp.c @@ -0,0 +1,740 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * + * 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 <linux/cache.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/smp.h> +#include <linux/spinlock.h> +#include <linux/threads.h> +#include <linux/export.h> +#include <linux/time.h> +#include <linux/timex.h> +#include <linux/sched/mm.h> +#include <linux/cpumask.h> +#include <linux/cpu.h> +#include <linux/err.h> +#include <linux/ftrace.h> +#include <linux/irqdomain.h> +#include <linux/of.h> +#include <linux/of_irq.h> + +#include <linux/atomic.h> +#include <asm/cpu.h> +#include <asm/ginvt.h> +#include <asm/processor.h> +#include <asm/idle.h> +#include <asm/r4k-timer.h> +#include <asm/mips-cps.h> +#include <asm/mmu_context.h> +#include <asm/time.h> +#include <asm/setup.h> +#include <asm/maar.h> + +int __cpu_number_map[CONFIG_MIPS_NR_CPU_NR_MAP]; /* 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 TCs (or siblings in Intel speak) per CPU core */ +int smp_num_siblings = 1; +EXPORT_SYMBOL(smp_num_siblings); + +/* representing the TCs (or siblings in Intel speak) 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 logical 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; + +cpumask_t cpu_coherent_mask; + +unsigned int smp_max_threads __initdata = UINT_MAX; + +static int __init early_nosmt(char *s) +{ + smp_max_threads = 1; + return 0; +} +early_param("nosmt", early_nosmt); + +static int __init early_smt(char *s) +{ + get_option(&s, &smp_max_threads); + /* Ensure at least one thread is available */ + smp_max_threads = clamp_val(smp_max_threads, 1U, UINT_MAX); + return 0; +} +early_param("smt", early_smt); + +#ifdef CONFIG_GENERIC_IRQ_IPI +static struct irq_desc *call_desc; +static struct irq_desc *sched_desc; +#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) { + 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]); + } + } + } else + cpumask_set_cpu(cpu, &cpu_sibling_map[cpu]); +} + +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]); +} + +const struct plat_smp_ops *mp_ops; +EXPORT_SYMBOL(mp_ops); + +void register_smp_ops(const struct plat_smp_ops *ops) +{ + if (mp_ops) + printk(KERN_WARNING "Overriding previously set SMP ops\n"); + + mp_ops = ops; +} + +#ifdef CONFIG_GENERIC_IRQ_IPI +void mips_smp_send_ipi_single(int cpu, unsigned int action) +{ + mips_smp_send_ipi_mask(cpumask_of(cpu), action); +} + +void mips_smp_send_ipi_mask(const struct cpumask *mask, unsigned int action) +{ + unsigned long flags; + unsigned int core; + int cpu; + + local_irq_save(flags); + + switch (action) { + case SMP_CALL_FUNCTION: + __ipi_send_mask(call_desc, mask); + break; + + case SMP_RESCHEDULE_YOURSELF: + __ipi_send_mask(sched_desc, mask); + break; + + default: + BUG(); + } + + if (mips_cpc_present()) { + for_each_cpu(cpu, mask) { + if (cpus_are_siblings(cpu, smp_processor_id())) + continue; + + core = cpu_core(&cpu_data[cpu]); + + while (!cpumask_test_cpu(cpu, &cpu_coherent_mask)) { + mips_cm_lock_other_cpu(cpu, CM_GCR_Cx_OTHER_BLOCK_LOCAL); + mips_cpc_lock_other(core); + write_cpc_co_cmd(CPC_Cx_CMD_PWRUP); + mips_cpc_unlock_other(); + mips_cm_unlock_other(); + } + } + } + + local_irq_restore(flags); +} + + +static irqreturn_t ipi_resched_interrupt(int irq, void *dev_id) +{ + scheduler_ipi(); + + return IRQ_HANDLED; +} + +static irqreturn_t ipi_call_interrupt(int irq, void *dev_id) +{ + generic_smp_call_function_interrupt(); + + return IRQ_HANDLED; +} + +static void smp_ipi_init_one(unsigned int virq, const char *name, + irq_handler_t handler) +{ + int ret; + + irq_set_handler(virq, handle_percpu_irq); + ret = request_irq(virq, handler, IRQF_PERCPU, name, NULL); + BUG_ON(ret); +} + +static unsigned int call_virq, sched_virq; + +int mips_smp_ipi_allocate(const struct cpumask *mask) +{ + int virq; + struct irq_domain *ipidomain; + struct device_node *node; + + node = of_irq_find_parent(of_root); + ipidomain = irq_find_matching_host(node, DOMAIN_BUS_IPI); + + /* + * Some platforms have half DT setup. So if we found irq node but + * didn't find an ipidomain, try to search for one that is not in the + * DT. + */ + if (node && !ipidomain) + ipidomain = irq_find_matching_host(NULL, DOMAIN_BUS_IPI); + + /* + * There are systems which use IPI IRQ domains, but only have one + * registered when some runtime condition is met. For example a Malta + * kernel may include support for GIC & CPU interrupt controller IPI + * IRQ domains, but if run on a system with no GIC & no MT ASE then + * neither will be supported or registered. + * + * We only have a problem if we're actually using multiple CPUs so fail + * loudly if that is the case. Otherwise simply return, skipping IPI + * setup, if we're running with only a single CPU. + */ + if (!ipidomain) { + BUG_ON(num_present_cpus() > 1); + return 0; + } + + virq = irq_reserve_ipi(ipidomain, mask); + BUG_ON(!virq); + if (!call_virq) + call_virq = virq; + + virq = irq_reserve_ipi(ipidomain, mask); + BUG_ON(!virq); + if (!sched_virq) + sched_virq = virq; + + if (irq_domain_is_ipi_per_cpu(ipidomain)) { + int cpu; + + for_each_cpu(cpu, mask) { + smp_ipi_init_one(call_virq + cpu, "IPI call", + ipi_call_interrupt); + smp_ipi_init_one(sched_virq + cpu, "IPI resched", + ipi_resched_interrupt); + } + } else { + smp_ipi_init_one(call_virq, "IPI call", ipi_call_interrupt); + smp_ipi_init_one(sched_virq, "IPI resched", + ipi_resched_interrupt); + } + + return 0; +} + +int mips_smp_ipi_free(const struct cpumask *mask) +{ + struct irq_domain *ipidomain; + struct device_node *node; + + node = of_irq_find_parent(of_root); + ipidomain = irq_find_matching_host(node, DOMAIN_BUS_IPI); + + /* + * Some platforms have half DT setup. So if we found irq node but + * didn't find an ipidomain, try to search for one that is not in the + * DT. + */ + if (node && !ipidomain) + ipidomain = irq_find_matching_host(NULL, DOMAIN_BUS_IPI); + + BUG_ON(!ipidomain); + + if (irq_domain_is_ipi_per_cpu(ipidomain)) { + int cpu; + + for_each_cpu(cpu, mask) { + free_irq(call_virq + cpu, NULL); + free_irq(sched_virq + cpu, NULL); + } + } + irq_destroy_ipi(call_virq, mask); + irq_destroy_ipi(sched_virq, mask); + return 0; +} + + +static int __init mips_smp_ipi_init(void) +{ + if (num_possible_cpus() == 1) + return 0; + + mips_smp_ipi_allocate(cpu_possible_mask); + + call_desc = irq_to_desc(call_virq); + sched_desc = irq_to_desc(sched_virq); + + return 0; +} +early_initcall(mips_smp_ipi_init); +#endif + +/* + * First C code run on the secondary CPUs after being started up by + * the master. + */ +asmlinkage void start_secondary(void) +{ + unsigned int cpu = raw_smp_processor_id(); + + cpu_probe(); + per_cpu_trap_init(false); + rcu_cpu_starting(cpu); + mips_clockevent_init(); + mp_ops->init_secondary(); + cpu_report(); + maar_init(); + + /* + * XXX parity protection should be folded in here when it's converted + * to an option instead of something based on .cputype + */ + + calibrate_delay(); + cpu_data[cpu].udelay_val = loops_per_jiffy; + + set_cpu_sibling_map(cpu); + set_cpu_core_map(cpu); + + cpumask_set_cpu(cpu, &cpu_coherent_mask); + notify_cpu_starting(cpu); + + /* Notify boot CPU that we're starting & ready to sync counters */ + complete(&cpu_starting); + + synchronise_count_slave(cpu); + + /* The CPU is running and counters synchronised, 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 ->smp_finish(), enabling it too early + * is dangerous. + */ + WARN_ON_ONCE(!irqs_disabled()); + mp_ops->smp_finish(); + + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); +} + +static void stop_this_cpu(void *dummy) +{ + /* + * Remove this CPU: + */ + + set_cpu_online(smp_processor_id(), false); + calculate_cpu_foreign_map(); + local_irq_disable(); + while (1); +} + +void smp_send_stop(void) +{ + smp_call_function(stop_this_cpu, NULL, 0); +} + +void __init smp_cpus_done(unsigned int max_cpus) +{ +} + +/* 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; + mp_ops->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 + cpumask_copy(&cpu_coherent_mask, cpu_possible_mask); +} + +/* preload SMP state for boot cpu */ +void smp_prepare_boot_cpu(void) +{ + if (mp_ops->prepare_boot_cpu) + mp_ops->prepare_boot_cpu(); + set_cpu_possible(0, true); + set_cpu_online(0, true); +} + +int __cpu_up(unsigned int cpu, struct task_struct *tidle) +{ + int err; + + err = mp_ops->boot_secondary(cpu, tidle); + if (err) + return err; + + /* Wait for CPU to start and be ready to sync counters */ + if (!wait_for_completion_timeout(&cpu_starting, + msecs_to_jiffies(1000))) { + pr_crit("CPU%u: failed to start\n", cpu); + return -EIO; + } + + synchronise_count_master(cpu); + + /* Wait for CPU to finish startup & mark itself online before return */ + wait_for_completion(&cpu_running); + return 0; +} + +/* Not really SMP stuff ... */ +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) +{ + if (cpu_has_mmid) { + htw_stop(); + ginvt_full(); + sync_ginv(); + instruction_hazard(); + htw_start(); + return; + } + + on_each_cpu(flush_tlb_all_ipi, NULL, 1); +} + +static void flush_tlb_mm_ipi(void *mm) +{ + drop_mmu_context((struct mm_struct *)mm); +} + +/* + * Special Variant of smp_call_function for use by TLB functions: + * + * o No return value + * o collapses to normal function call on UP kernels + * o collapses to normal function call on systems with a single shared + * primary cache. + */ +static inline void smp_on_other_tlbs(void (*func) (void *info), void *info) +{ + smp_call_function(func, info, 1); +} + +static inline void smp_on_each_tlb(void (*func) (void *info), void *info) +{ + preempt_disable(); + + smp_on_other_tlbs(func, info); + func(info); + + preempt_enable(); +} + +/* + * The following tlb flush calls are invoked when old translations are + * being torn down, or pte attributes are changing. For single threaded + * address spaces, a new context is obtained on the current cpu, and tlb + * context on other cpus are invalidated to force a new context allocation + * at switch_mm time, should the mm ever be used on other cpus. For + * multithreaded address spaces, inter-CPU interrupts have to be sent. + * Another case where inter-CPU interrupts are required is when the target + * mm might be active on another cpu (eg debuggers doing the flushes on + * behalf of debugees, kswapd stealing pages from another process etc). + * Kanoj 07/00. + */ + +void flush_tlb_mm(struct mm_struct *mm) +{ + if (!mm) + return; + + if (atomic_read(&mm->mm_users) == 0) + return; /* happens as a result of exit_mmap() */ + + preempt_disable(); + + if (cpu_has_mmid) { + /* + * No need to worry about other CPUs - the ginvt in + * drop_mmu_context() will be globalized. + */ + } else if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) { + smp_on_other_tlbs(flush_tlb_mm_ipi, mm); + } else { + unsigned int cpu; + + for_each_online_cpu(cpu) { + if (cpu != smp_processor_id() && cpu_context(cpu, mm)) + set_cpu_context(cpu, mm, 0); + } + } + drop_mmu_context(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; + unsigned long addr; + u32 old_mmid; + + preempt_disable(); + if (cpu_has_mmid) { + htw_stop(); + old_mmid = read_c0_memorymapid(); + write_c0_memorymapid(cpu_asid(0, mm)); + mtc0_tlbw_hazard(); + addr = round_down(start, PAGE_SIZE * 2); + end = round_up(end, PAGE_SIZE * 2); + do { + ginvt_va_mmid(addr); + sync_ginv(); + addr += PAGE_SIZE * 2; + } while (addr < end); + write_c0_memorymapid(old_mmid); + instruction_hazard(); + htw_start(); + } else if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) { + struct flush_tlb_data fd = { + .vma = vma, + .addr1 = start, + .addr2 = end, + }; + + smp_on_other_tlbs(flush_tlb_range_ipi, &fd); + local_flush_tlb_range(vma, start, end); + } else { + unsigned int cpu; + int exec = vma->vm_flags & VM_EXEC; + + for_each_online_cpu(cpu) { + /* + * flush_cache_range() will only fully flush icache if + * the VMA is executable, otherwise we must invalidate + * ASID without it appearing to has_valid_asid() as if + * mm has been completely unused by that CPU. + */ + if (cpu != smp_processor_id() && cpu_context(cpu, mm)) + set_cpu_context(cpu, mm, !exec); + } + 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) +{ + u32 old_mmid; + + preempt_disable(); + if (cpu_has_mmid) { + htw_stop(); + old_mmid = read_c0_memorymapid(); + write_c0_memorymapid(cpu_asid(0, vma->vm_mm)); + mtc0_tlbw_hazard(); + ginvt_va_mmid(page); + sync_ginv(); + write_c0_memorymapid(old_mmid); + instruction_hazard(); + htw_start(); + } else if ((atomic_read(&vma->vm_mm->mm_users) != 1) || + (current->mm != vma->vm_mm)) { + struct flush_tlb_data fd = { + .vma = vma, + .addr1 = page, + }; + + smp_on_other_tlbs(flush_tlb_page_ipi, &fd); + local_flush_tlb_page(vma, page); + } else { + unsigned int cpu; + + for_each_online_cpu(cpu) { + /* + * flush_cache_page() only does partial flushes, so + * invalidate ASID without it appearing to + * has_valid_asid() as if mm has been completely unused + * by that CPU. + */ + if (cpu != smp_processor_id() && cpu_context(cpu, vma->vm_mm)) + set_cpu_context(cpu, vma->vm_mm, 1); + } + local_flush_tlb_page(vma, page); + } + preempt_enable(); +} + +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) +{ + smp_on_each_tlb(flush_tlb_one_ipi, (void *) vaddr); +} + +EXPORT_SYMBOL(flush_tlb_page); +EXPORT_SYMBOL(flush_tlb_one); + +#ifdef CONFIG_HOTPLUG_CORE_SYNC_DEAD +void arch_cpuhp_cleanup_dead_cpu(unsigned int cpu) +{ + if (mp_ops->cleanup_dead_cpu) + mp_ops->cleanup_dead_cpu(cpu); +} +#endif + +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST + +static void tick_broadcast_callee(void *info) +{ + tick_receive_broadcast(); +} + +static DEFINE_PER_CPU(call_single_data_t, tick_broadcast_csd) = + CSD_INIT(tick_broadcast_callee, NULL); + +void tick_broadcast(const struct cpumask *mask) +{ + call_single_data_t *csd; + int cpu; + + for_each_cpu(cpu, mask) { + csd = &per_cpu(tick_broadcast_csd, cpu); + smp_call_function_single_async(cpu, csd); + } +} + +#endif /* CONFIG_GENERIC_CLOCKEVENTS_BROADCAST */ |