Merge tag 'lsm-pr-20240131' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm

[nvme.git] / arch / loongarch / kernel / smp.c

// 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 <linux/acpi.h>
#include <linux/cpu.h>
#include <linux/cpumask.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/profile.h>
#include <linux/seq_file.h>
#include <linux/smp.h>
#include <linux/threads.h>
#include <linux/export.h>
#include <linux/syscore_ops.h>
#include <linux/time.h>
#include <linux/tracepoint.h>
#include <linux/sched/hotplug.h>
#include <linux/sched/task_stack.h>

#include <asm/cpu.h>
#include <asm/idle.h>
#include <asm/loongson.h>
#include <asm/mmu_context.h>
#include <asm/numa.h>
#include <asm/processor.h>
#include <asm/setup.h>
#include <asm/time.h>

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);

/* 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);
        wbflush();

        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 arch_smp_send_reschedule(int cpu)
{
        loongson_send_ipi_single(cpu, SMP_RESCHEDULE);
}
EXPORT_SYMBOL_GPL(arch_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;
}

static void __init fdt_smp_setup(void)
{
#ifdef CONFIG_OF
        unsigned int cpu, cpuid;
        struct device_node *node = NULL;

        for_each_of_cpu_node(node) {
                if (!of_device_is_available(node))
                        continue;

                cpuid = of_get_cpu_hwid(node, 0);
                if (cpuid >= nr_cpu_ids)
                        continue;

                if (cpuid == loongson_sysconf.boot_cpu_id) {
                        cpu = 0;
                        numa_add_cpu(cpu);
                } else {
                        cpu = cpumask_next_zero(-1, cpu_present_mask);
                }

                num_processors++;
                set_cpu_possible(cpu, true);
                set_cpu_present(cpu, true);
                __cpu_number_map[cpuid] = cpu;
                __cpu_logical_map[cpu] = cpuid;
        }

        loongson_sysconf.nr_cpus = num_processors;
        set_bit(0, loongson_sysconf.cores_io_master);
#endif
}

void __init loongson_smp_setup(void)
{
        fdt_smp_setup();

        if (loongson_sysconf.cores_per_package == 0)
                loongson_sysconf.cores_per_package = num_processors;

        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;

        parse_acpi_topology();

        for (i = 0; i < loongson_sysconf.nr_cpus; i++) {
                set_cpu_present(i, true);
                csr_mail_send(0, __cpu_logical_map[i], 0);
                cpu_data[i].global_id = __cpu_logical_map[i];
        }

        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].package =
                     cpu_logical_map(cpu) / loongson_sysconf.cores_per_package;
        cpu_data[cpu].core = pptt_enabled ? cpu_data[cpu].core :
                     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 __noreturn arch_cpu_idle_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();
        BUG();
}

#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);

        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 = raw_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);
}

#ifdef CONFIG_PROFILING
int setup_profiling_timer(unsigned int multiplier)
{
        return 0;
}
#endif

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);