Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 701 insertions, 0 deletions

diff --git a/arch/loongarch/kernel/smp.c b/arch/loongarch/kernel/smp.c
new file mode 100644
index 0000000000..42e3a0e189
--- /dev/null
+++ b/arch/loongarch/kernel/smp.c
@@ -0,0 +1,701 @@
+// 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();
+
+	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));
+	rcu_cpu_starting(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);