1 // SPDX-License-Identifier: GPL-2.0-only
27 #include <linux/irqchip/arm-gic-v3.h>
60  * so we need some other way of telling a new secondary core
98 	return -ENOSYS;  in op_cpu_kill()
104  * Boot a secondary CPU, and assign it the specified idle task.
111 	if (ops->cpu_boot)  in boot_secondary()
112 		return ops->cpu_boot(cpu);  in boot_secondary()
114 	return -EOPNOTSUPP;  in boot_secondary()
125 	 * We need to tell the secondary core where to find its stack and the  in __cpu_up()
134 		if (ret != -EPERM)  in __cpu_up()
170 			pr_crit("CPU%u: does not support 52-bit VAs\n", cpu);  in __cpu_up()
181 	return -EIO;  in __cpu_up()
200  * This is the secondary CPU boot entry.  We're using this CPUs
215 	current->active_mm = mm;  in secondary_start_kernel()
237 	if (ops->cpu_postboot)  in secondary_start_kernel()
238 		ops->cpu_postboot();  in secondary_start_kernel()
260 	pr_info("CPU%u: Booted secondary processor 0x%010lx [0x%08x]\n",  in secondary_start_kernel()
268 	 * Secondary CPUs enter the kernel with all DAIF exceptions masked.  in secondary_start_kernel()
271 	 * as the root irqchip has already been detected and initialized we can  in secondary_start_kernel()
291 	if (!ops || !ops->cpu_die)  in op_cpu_disable()
292 		return -EOPNOTSUPP;  in op_cpu_disable()
295 	 * We may need to abort a hot unplug for some other mechanism-specific  in op_cpu_disable()
298 	if (ops->cpu_disable)  in op_cpu_disable()
299 		return ops->cpu_disable(cpu);  in op_cpu_disable()
320 	 * Take this CPU offline.  Once we clear this, we can't return,  in __cpu_disable()
327 	 * OK - migrate IRQs away from this CPU  in __cpu_disable()
340 	 * that it is really dead. We can only wait for an arbitrary length of  in op_cpu_kill()
343 	if (!ops->cpu_kill)  in op_cpu_kill()
346 	return ops->cpu_kill(cpu);  in op_cpu_kill()
361 	 * in-kernel synchronisation, try to get the firwmare to help us to  in arch_cpuhp_cleanup_dead_cpu()
391 	ops->cpu_die(cpu);  in cpu_die()
402 	if (ops && ops->cpu_die)  in __cpu_try_die()
403 		ops->cpu_die(cpu);  in __cpu_try_die()
408  * Kill the calling secondary CPU, early in bringup before it is turned
458 	 * The runtime per-cpu areas have been allocated by  in smp_prepare_boot_cpu()
459 	 * setup_per_cpu_areas(), and CPU0's boot time per-cpu area will be  in smp_prepare_boot_cpu()
460 	 * freed shortly, so we must move over to the runtime per-cpu area.  in smp_prepare_boot_cpu()
501 		return -ENODEV;  in smp_cpu_setup()
504 	if (ops->cpu_init(cpu))  in smp_cpu_setup()
505 		return -ENODEV;  in smp_cpu_setup()
522 		return -EPROBE_DEFER;  in arch_register_cpu()
528 		return -ENODEV;  in arch_register_cpu()
536 	c->hotpluggable = arch_cpu_is_hotpluggable(cpu);  in arch_register_cpu()
578  * acpi_map_gic_cpu_interface - parse processor MADT entry
586 	u64 hwid = processor->arm_mpidr;  in acpi_map_gic_cpu_interface()
588 	if (!(processor->flags &  in acpi_map_gic_cpu_interface()
625 	 * Set-up the ACPI parking protocol cpu entries  in acpi_map_gic_cpu_interface()
646 		return -EINVAL;  in acpi_parse_gic_cpu_interface()
648 	acpi_table_print_madt_entry(&header->common);  in acpi_parse_gic_cpu_interface()
708 		 * the logical map built from DT is validated and can  in of_parse_and_init_cpus()
724 			 * the enable-method so continue without  in of_parse_and_init_cpus()
757 		pr_warn("Number of cores (%d) exceeds configured maximum of %u - clipping\n",  in smp_init_cpus()
768 	 * and ACPI MADT entries) can be retrieved by matching the cpu hwid  in smp_init_cpus()
770 	 * If the cpu set-up fails, invalidate the cpu_logical_map entry.  in smp_init_cpus()
796 	 * secondary CPUs present.  in smp_prepare_cpus()
815 		err = ops->cpu_prepare(cpu);  in smp_prepare_cpus()
844 		seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i,  in arch_show_interrupts()
883  * that cpu_online_mask gets correctly updated and smp_send_stop() can skip
896 	 * that pseudo-NMIs are disabled. The "crash stop" code starts with  in ipi_cpu_crash_stop()
953  * Main handler for inter-processor interrupts
1016 	do_handle_IPI(irq - ipi_irq_base);  in ipi_handler()
1119 	 * dedicated IPI and we can safely handle spurious scheduler IPIs.  in arch_send_wakeup_ipi()
1140 	return num_online_cpus() - this_cpu_online;  in num_other_online_cpus()
1167 	 * can be called in the panic path and thus it doesn't seem wise to  in smp_send_stop()
1169 	 * - If a CPU comes online as we're running, we'll likely notice it  in smp_send_stop()
1171 	 *   with an NMI (assuming NMIs are enabled) since we re-snapshot the  in smp_send_stop()
1173 	 * - If we leave the function and see that CPUs are still online we'll  in smp_send_stop()
1176 	 *   the fact that there could be cases where a CPU can't be stopped.  in smp_send_stop()
1182 		pr_crit("SMP: stopping secondary CPUs\n");  in smp_send_stop()
1192 	while (num_other_online_cpus() && timeout--)  in smp_send_stop()
1209 		while (num_other_online_cpus() && timeout--)  in smp_send_stop()
1218 		pr_warn("SMP: failed to stop secondary CPUs %*pbl\n",  in smp_send_stop()
1230 	 * This function can be called twice in panic path, but obviously  in crash_smp_send_stop()
1257 	if (ops && ops->cpu_die)  in have_cpu_die()