/*
 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/* 
 * Mach Operating System
 * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 */
/*
 *      File:   kern/machine.c
 *      Author: Avadis Tevanian, Jr.
 *      Date:   1987
 *
 *      Support for machine independent machine abstraction.
 */

#include <string.h>

#include <mach/mach_types.h>
#include <mach/boolean.h>
#include <mach/kern_return.h>
#include <mach/machine.h>
#include <mach/host_info.h>
#include <mach/host_reboot.h>
#include <mach/host_priv_server.h>
#include <mach/processor_server.h>

#include <kern/kern_types.h>
#include <kern/counters.h>
#include <kern/cpu_data.h>
#include <kern/ipc_host.h>
#include <kern/host.h>
#include <kern/lock.h>
#include <kern/machine.h>
#include <kern/misc_protos.h>
#include <kern/processor.h>
#include <kern/queue.h>
#include <kern/sched.h>
#include <kern/task.h>
#include <kern/thread.h>

#include <IOKit/IOHibernatePrivate.h>

/*
 *      Exported variables:
 */

struct machine_info     machine_info;

/* Forwards */
void                    processor_doshutdown(
                                        processor_t                     processor);

/*
 *      processor_up:
 *
 *      Flag processor as up and running, and available
 *      for scheduling.
 */
void
processor_up(
        processor_t             processor)
{
        processor_set_t         pset = &default_pset;
        spl_t                           s;

        s = splsched();
        processor_lock(processor);
        init_ast_check(processor);
        simple_lock(&pset->sched_lock);
        pset_add_processor(pset, processor);
        enqueue_tail(&pset->active_queue, (queue_entry_t)processor);
        processor->state = PROCESSOR_RUNNING;
        simple_unlock(&pset->sched_lock);
        hw_atomic_add(&machine_info.avail_cpus, 1);
        ml_cpu_up();
        processor_unlock(processor);
        splx(s);
}

kern_return_t
host_reboot(
        host_priv_t             host_priv,
        int                             options)
{
        if (host_priv == HOST_PRIV_NULL)
                return (KERN_INVALID_HOST);

        assert(host_priv == &realhost);

        if (options & HOST_REBOOT_DEBUGGER) {
                Debugger("Debugger");
                return (KERN_SUCCESS);
        }

        halt_all_cpus(!(options & HOST_REBOOT_HALT));

        return (KERN_SUCCESS);
}

kern_return_t
processor_assign(
        __unused processor_t            processor,
        __unused processor_set_t        new_pset,
        __unused boolean_t              wait)
{
        return (KERN_FAILURE);
}

kern_return_t
processor_shutdown(
        processor_t                     processor)
{
        processor_set_t         pset;
        spl_t                           s;

        s = splsched();
        processor_lock(processor);
        if (processor->state == PROCESSOR_OFF_LINE) {
                /*
                 * Success if already shutdown.
                 */
                processor_unlock(processor);
                splx(s);

                return (KERN_SUCCESS);
        }

        if (processor->state == PROCESSOR_START) {
                /*
                 * Failure if currently being started.
                 */
                processor_unlock(processor);
                splx(s);

                return (KERN_FAILURE);
        }

        /*
         * Must lock the scheduling lock
         * to get at the processor state.
         */
        pset = processor->processor_set;
        if (pset != PROCESSOR_SET_NULL) {
                simple_lock(&pset->sched_lock);

                /*
                 * If the processor is dispatching, let it finish.
                 */
                while (processor->state == PROCESSOR_DISPATCHING) {
                        simple_unlock(&pset->sched_lock);
                        delay(1);
                        simple_lock(&pset->sched_lock);
                }

                /*
                 * Success if already being shutdown.
                 */
                if (processor->state == PROCESSOR_SHUTDOWN) {
                        simple_unlock(&pset->sched_lock);
                        processor_unlock(processor);
                        splx(s);

                        return (KERN_SUCCESS);
                }
        }
        else {
                /*
                 * Success, already being shutdown.
                 */
                processor_unlock(processor);
                splx(s);

                return (KERN_SUCCESS);
        }

        if (processor->state == PROCESSOR_IDLE) {
                remqueue(&pset->idle_queue, (queue_entry_t)processor);
                pset->idle_count--;
        }
        else
        if (processor->state == PROCESSOR_RUNNING)
                remqueue(&pset->active_queue, (queue_entry_t)processor);
        else
                panic("processor_shutdown");

        processor->state = PROCESSOR_SHUTDOWN;

        simple_unlock(&pset->sched_lock);

        processor_unlock(processor);

        processor_doshutdown(processor);
        splx(s);

        cpu_exit_wait(PROCESSOR_DATA(processor, slot_num));

        return (KERN_SUCCESS);
}

/*
 * Called at splsched.
 */
void
processor_doshutdown(
        processor_t                     processor)
{
        thread_t                        old_thread, self = current_thread();
        processor_set_t         pset;
        processor_t                     prev;
        int                                     pcount;

        /*
         *      Get onto the processor to shutdown
         */
        prev = thread_bind(self, processor);
        thread_block(THREAD_CONTINUE_NULL);

        processor_lock(processor);
        pset = processor->processor_set;
        simple_lock(&pset->sched_lock);

        if ((pcount = pset->processor_count) == 1) {
                simple_unlock(&pset->sched_lock);
                processor_unlock(processor);

                hibernate_vm_lock();

                processor_lock(processor);
                simple_lock(&pset->sched_lock);
        }

        assert(processor->state == PROCESSOR_SHUTDOWN);

        pset_remove_processor(pset, processor);
        simple_unlock(&pset->sched_lock);
        processor_unlock(processor);

        if (pcount == 1)
                hibernate_vm_unlock();

        /*
         *      Continue processor shutdown in shutdown context.
         */
        thread_bind(self, prev);
        old_thread = machine_processor_shutdown(self, processor_offline, processor);

        thread_begin(self, self->last_processor);

        thread_dispatch(old_thread);

        /*
         * If we just shutdown another processor, move the
         * timer call outs to the current processor.
         */
        if (processor != current_processor()) {
                processor_lock(processor);
                if (    processor->state == PROCESSOR_OFF_LINE  ||
                                processor->state == PROCESSOR_SHUTDOWN  )
                        timer_call_shutdown(processor);
                processor_unlock(processor);
        }
}

/*
 *      Complete the shutdown and place the processor offline.
 *
 *      Called at splsched in the shutdown context.
 */
void
processor_offline(
        processor_t             processor)
{
        thread_t                thread, old_thread = processor->active_thread;

        thread = processor->idle_thread;
        processor->active_thread = thread;
        processor->current_pri = IDLEPRI;

        processor->last_dispatch = mach_absolute_time();
        timer_switch((uint32_t)processor->last_dispatch,
                                                        &PROCESSOR_DATA(processor, offline_timer));

        thread_done(old_thread, thread, processor);

        machine_set_current_thread(thread);

        thread_begin(thread, processor);

        thread_dispatch(old_thread);

        PMAP_DEACTIVATE_KERNEL(PROCESSOR_DATA(processor, slot_num));

        processor_lock(processor);
        processor->state = PROCESSOR_OFF_LINE;
        hw_atomic_sub(&machine_info.avail_cpus, 1);
        ml_cpu_down();
        processor_unlock(processor);

        cpu_sleep();
        panic("zombie processor");
        /*NOTREACHED*/
}

kern_return_t
host_get_boot_info(
        host_priv_t         host_priv,
        kernel_boot_info_t  boot_info)
{
        const char *src = "";
        if (host_priv == HOST_PRIV_NULL)
                return (KERN_INVALID_HOST);

        assert(host_priv == &realhost);

        /*
         * Copy first operator string terminated by '\0' followed by
         *      standardized strings generated from boot string.
         */
        src = machine_boot_info(boot_info, KERNEL_BOOT_INFO_MAX);
        if (src != boot_info)
                (void) strncpy(boot_info, src, KERNEL_BOOT_INFO_MAX);

        return (KERN_SUCCESS);
}