--- /dev/null
+#include <lwk/kernel.h>
+#include <lwk/init.h>
+#include <lwk/cpuinfo.h>
+#include <lwk/smp.h>
+#include <lwk/delay.h>
+#include <lwk/bootmem.h>
+#include <lwk/task.h>
+#include <lwk/sched.h>
+#include <arch/atomic.h>
+#include <arch/apicdef.h>
+#include <arch/apic.h>
+#include <arch/desc.h>
+
+/**
+ * MP boot trampoline 80x86 program as an array.
+ */
+extern unsigned char trampoline_data[];
+extern unsigned char trampoline_end[];
+
+/**
+ * These specify the initial stack pointer and instruction pointer for a
+ * newly booted CPU.
+ */
+extern volatile unsigned long init_rsp;
+extern void (*initial_code)(void);
+
+void __init
+start_secondary(void)
+{
+ cpu_init();
+ cpu_set(this_cpu, cpu_online_map);
+ schedule(); /* runs idle_task, since that's the only task
+ * on the CPU's run queue at this point */
+}
+
+void __init
+arch_boot_cpu(unsigned int cpu)
+{
+ union task_union *new_task_union;
+ struct task_struct *new_task;
+
+ /*
+ * Setup the 'trampoline' cpu boot code. The trampoline contains the
+ * first code executed by the CPU being booted. x86 CPUs boot in
+ * pre-historic 16-bit 'real mode'... the trampoline does the messy
+ * work to get us to 64-bit long mode and then calls the *initial_code
+ * kernel entry function.
+ */
+ memcpy(__va(SMP_TRAMPOLINE_BASE), trampoline_data,
+ trampoline_end - trampoline_data
+ );
+
+ /*
+ * Allocate memory for the new CPU's GDT.
+ */
+ cpu_gdt_descr[cpu].address = (unsigned long) kmem_get_pages(0);
+
+ /*
+ * Allocate memory for the new CPU's bootstrap task.
+ */
+ new_task_union = kmem_get_pages(TASK_ORDER);
+ new_task = &new_task_union->task_info;
+
+ /*
+ * Initialize the bare minimum info needed to bootstrap the new CPU.
+ */
+ new_task->id = 0;
+ new_task->aspace = &bootstrap_aspace;
+ new_task->cpu_id = cpu;
+ strcpy(new_task->name, "bootstrap");
+ list_head_init(&new_task->sched_link);
+
+ /*
+ * Set the initial kernel entry point and stack pointer for the new CPU.
+ */
+ initial_code = start_secondary;
+ init_rsp = (unsigned long)new_task_union
+ + sizeof(union task_union) - 1;
+
+ /*
+ * Boot it!
+ */
+ lapic_send_init_ipi(cpu);
+ lapic_send_startup_ipi(cpu, SMP_TRAMPOLINE_BASE);
+ lapic_send_startup_ipi(cpu, SMP_TRAMPOLINE_BASE);
+}
+
