kernel: Break out kernel primitives into separate files and move to separate dir.

No code changed, just shuffling stuff around. This should make it easier to
build only select parts kernel and use different implementations.

Change-Id: Ie1f00f93008833ce38419d760afd70062c5e22b5

8 files changed, 881 insertions, 0 deletions

diff --git a/firmware/kernel/include/corelock.h b/firmware/kernel/include/corelock.h
new file mode 100644
index 0000000000..79302e0e3c
--- /dev/null
+++ b/firmware/kernel/include/corelock.h
@@ -0,0 +1,53 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2002 by Ulf Ralberg
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+
+#ifndef CORELOCK_H
+#define CORELOCK_H
+
+#include "config.h"
+
+#ifndef HAVE_CORELOCK_OBJECT
+
+/* No atomic corelock op needed or just none defined */
+#define corelock_init(cl)
+#define corelock_lock(cl)
+#define corelock_try_lock(cl)
+#define corelock_unlock(cl)
+
+#else
+
+/* No reliable atomic instruction available - use Peterson's algorithm */
+struct corelock
+{
+    volatile unsigned char myl[NUM_CORES];
+    volatile unsigned char turn;
+} __attribute__((packed));
+
+/* Too big to inline everywhere */
+extern void corelock_init(struct corelock *cl);
+extern void corelock_lock(struct corelock *cl);
+extern int  corelock_try_lock(struct corelock *cl);
+extern void corelock_unlock(struct corelock *cl);
+
+#endif /* HAVE_CORELOCK_OBJECT */
+
+#endif /* CORELOCK_H */
diff --git a/firmware/kernel/include/kernel.h b/firmware/kernel/include/kernel.h
new file mode 100644
index 0000000000..fafff25ce4
--- /dev/null
+++ b/firmware/kernel/include/kernel.h
@@ -0,0 +1,69 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2002 by Björn Stenberg
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#ifndef KERNEL_H
+#define KERNEL_H
+
+#include "config.h"
+
+#include "system.h"
+#include "queue.h"
+#include "mutex.h"
+#include "tick.h"
+
+#ifdef INCLUDE_TIMEOUT_API
+#include "timeout.h"
+#endif
+
+#ifdef HAVE_SEMAPHORE_OBJECTS
+#include "semaphore.h"
+#endif
+
+#ifdef HAVE_CORELOCK_OBJECT
+#include "corelock.h"
+#endif
+
+#define OBJ_WAIT_TIMEDOUT     (-1)
+#define OBJ_WAIT_FAILED       0
+#define OBJ_WAIT_SUCCEEDED    1
+
+#define TIMEOUT_BLOCK   -1
+#define TIMEOUT_NOBLOCK  0
+
+static inline void kernel_init(void)
+{
+    /* Init the threading API */
+    init_threads();
+
+    /* Other processors will not reach this point in a multicore build.
+     * In a single-core build with multiple cores they fall-through and
+     * sleep in cop_main without returning. */
+    if (CURRENT_CORE == CPU)
+    {
+        init_queues();
+        init_tick();
+#ifdef KDEV_INIT
+        kernel_device_init();
+#endif
+    }
+}
+
+
+#endif /* KERNEL_H */
diff --git a/firmware/kernel/include/mutex.h b/firmware/kernel/include/mutex.h
new file mode 100644
index 0000000000..bcf5701bd9
--- /dev/null
+++ b/firmware/kernel/include/mutex.h
@@ -0,0 +1,62 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2002 by Björn Stenberg
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#ifndef MUTEX_H
+#define MUTEX_H
+
+#include <stdbool.h>
+#include "config.h"
+#include "thread.h"
+
+struct mutex
+{
+    struct thread_entry *queue;         /* waiter list */
+    int recursion;                      /* lock owner recursion count */
+#ifdef HAVE_PRIORITY_SCHEDULING
+    struct blocker blocker;             /* priority inheritance info
+                                           for waiters */
+    bool no_preempt;                    /* don't allow higher-priority thread
+                                           to be scheduled even if woken */
+#else
+    struct thread_entry *thread;        /* Indicates owner thread - an owner
+                                           implies a locked state - same goes
+                                           for priority scheduling
+                                           (in blocker struct for that) */
+#endif
+    IF_COP( struct corelock cl; )       /* multiprocessor sync */
+};
+
+extern void mutex_init(struct mutex *m);
+extern void mutex_lock(struct mutex *m);
+extern void mutex_unlock(struct mutex *m);
+#ifdef HAVE_PRIORITY_SCHEDULING
+/* Deprecated temporary function to disable mutex preempting a thread on
+ * unlock - firmware/drivers/fat.c and a couple places in apps/buffering.c -
+ * reliance on it is a bug! */
+static inline void mutex_set_preempt(struct mutex *m, bool preempt)
+    { m->no_preempt = !preempt; }
+#else
+/* Deprecated but needed for now - firmware/drivers/ata_mmc.c */
+static inline bool mutex_test(const struct mutex *m)
+    { return m->thread != NULL; }
+#endif /* HAVE_PRIORITY_SCHEDULING */
+
+#endif /* MUTEX_H */
diff --git a/firmware/kernel/include/queue.h b/firmware/kernel/include/queue.h
new file mode 100644
index 0000000000..1b404f8297
--- /dev/null
+++ b/firmware/kernel/include/queue.h
@@ -0,0 +1,157 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2002 by Björn Stenberg
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#ifndef QUEUE_H
+#define QUEUE_H
+
+#include <stdint.h>
+#include "config.h"
+#include "thread.h"
+
+/* System defined message ID's - |sign bit = 1|class|id| */
+/* Event class list */
+#define SYS_EVENT_CLS_QUEUE   0
+#define SYS_EVENT_CLS_USB     1
+#define SYS_EVENT_CLS_POWER   2
+#define SYS_EVENT_CLS_FILESYS 3
+#define SYS_EVENT_CLS_PLUG    4
+#define SYS_EVENT_CLS_MISC    5
+#define SYS_EVENT_CLS_PRIVATE 7 /* For use inside plugins */
+/* make sure SYS_EVENT_CLS_BITS has enough range */
+
+/* Bit 31->|S|c...c|i...i| */
+#define SYS_EVENT                 ((long)(int)(1 << 31))
+#define SYS_EVENT_CLS_BITS        (3)
+#define SYS_EVENT_CLS_SHIFT       (31-SYS_EVENT_CLS_BITS)
+#define SYS_EVENT_CLS_MASK        (((1l << SYS_EVENT_CLS_BITS)-1) << SYS_EVENT_SHIFT)
+#define MAKE_SYS_EVENT(cls, id)   (SYS_EVENT | ((long)(cls) << SYS_EVENT_CLS_SHIFT) | (long)(id))
+/* Macros for extracting codes */
+#define SYS_EVENT_CLS(e)          (((e) & SYS_EVENT_CLS_MASK) >> SYS_EVENT_SHIFT)
+#define SYS_EVENT_ID(e)           ((e) & ~(SYS_EVENT|SYS_EVENT_CLS_MASK))
+
+#define SYS_TIMEOUT               MAKE_SYS_EVENT(SYS_EVENT_CLS_QUEUE, 0)
+#define SYS_USB_CONNECTED         MAKE_SYS_EVENT(SYS_EVENT_CLS_USB, 0)
+#define SYS_USB_CONNECTED_ACK     MAKE_SYS_EVENT(SYS_EVENT_CLS_USB, 1)
+#define SYS_USB_DISCONNECTED      MAKE_SYS_EVENT(SYS_EVENT_CLS_USB, 2)
+#define SYS_USB_LUN_LOCKED        MAKE_SYS_EVENT(SYS_EVENT_CLS_USB, 4)
+#define SYS_USB_READ_DATA         MAKE_SYS_EVENT(SYS_EVENT_CLS_USB, 5)
+#define SYS_USB_WRITE_DATA        MAKE_SYS_EVENT(SYS_EVENT_CLS_USB, 6)
+#define SYS_POWEROFF              MAKE_SYS_EVENT(SYS_EVENT_CLS_POWER, 0)
+#define SYS_CHARGER_CONNECTED     MAKE_SYS_EVENT(SYS_EVENT_CLS_POWER, 1)
+#define SYS_CHARGER_DISCONNECTED  MAKE_SYS_EVENT(SYS_EVENT_CLS_POWER, 2)
+#define SYS_BATTERY_UPDATE        MAKE_SYS_EVENT(SYS_EVENT_CLS_POWER, 3)
+#define SYS_FS_CHANGED            MAKE_SYS_EVENT(SYS_EVENT_CLS_FILESYS, 0)
+#define SYS_HOTSWAP_INSERTED      MAKE_SYS_EVENT(SYS_EVENT_CLS_PLUG, 0)
+#define SYS_HOTSWAP_EXTRACTED     MAKE_SYS_EVENT(SYS_EVENT_CLS_PLUG, 1)
+#define SYS_PHONE_PLUGGED         MAKE_SYS_EVENT(SYS_EVENT_CLS_PLUG, 2)
+#define SYS_PHONE_UNPLUGGED       MAKE_SYS_EVENT(SYS_EVENT_CLS_PLUG, 3)
+#define SYS_REMOTE_PLUGGED        MAKE_SYS_EVENT(SYS_EVENT_CLS_PLUG, 4)
+#define SYS_REMOTE_UNPLUGGED      MAKE_SYS_EVENT(SYS_EVENT_CLS_PLUG, 5)
+#define SYS_CAR_ADAPTER_RESUME    MAKE_SYS_EVENT(SYS_EVENT_CLS_MISC, 0)
+#define SYS_CALL_INCOMING         MAKE_SYS_EVENT(SYS_EVENT_CLS_MISC, 3)
+#define SYS_CALL_HUNG_UP          MAKE_SYS_EVENT(SYS_EVENT_CLS_MISC, 4)
+#define SYS_VOLUME_CHANGED        MAKE_SYS_EVENT(SYS_EVENT_CLS_MISC, 5)
+
+#define IS_SYSEVENT(ev)           ((ev & SYS_EVENT) == SYS_EVENT)
+
+#define MAX_NUM_QUEUES 32
+#define QUEUE_LENGTH 16 /* MUST be a power of 2 */
+#define QUEUE_LENGTH_MASK (QUEUE_LENGTH - 1)
+
+struct queue_event
+{
+    long     id;
+    intptr_t data;
+};
+
+#ifdef HAVE_EXTENDED_MESSAGING_AND_NAME
+struct queue_sender_list
+{
+    /* If non-NULL, there is a thread waiting for the corresponding event */
+    /* Must be statically allocated to put in non-cached ram. */
+    struct thread_entry *senders[QUEUE_LENGTH]; /* message->thread map */
+    struct thread_entry *list;                  /* list of senders in map */
+    /* Send info for last message dequeued or NULL if replied or not sent */
+    struct thread_entry * volatile curr_sender;
+#ifdef HAVE_PRIORITY_SCHEDULING
+    struct blocker blocker;
+#endif
+};
+#endif /* HAVE_EXTENDED_MESSAGING_AND_NAME */
+
+#ifdef HAVE_PRIORITY_SCHEDULING
+#define QUEUE_GET_THREAD(q) \
+    (((q)->send == NULL) ? NULL : (q)->send->blocker.thread)
+#else
+/* Queue without priority enabled have no owner provision _at this time_ */
+#define QUEUE_GET_THREAD(q) \
+    (NULL)
+#endif
+
+struct event_queue
+{
+    struct thread_entry *queue;         /* waiter list */
+    struct queue_event events[QUEUE_LENGTH]; /* list of events */
+    unsigned int volatile read;         /* head of queue */
+    unsigned int volatile write;        /* tail of queue */
+#ifdef HAVE_EXTENDED_MESSAGING_AND_NAME
+    struct queue_sender_list * volatile send; /* list of threads waiting for
+                                           reply to an event */
+#ifdef HAVE_PRIORITY_SCHEDULING
+    struct blocker *blocker_p;          /* priority inheritance info
+                                           for sync message senders */
+#endif
+#endif
+    IF_COP( struct corelock cl; )       /* multiprocessor sync */
+};
+
+extern void queue_init(struct event_queue *q, bool register_queue);
+extern void queue_delete(struct event_queue *q);
+extern void queue_wait(struct event_queue *q, struct queue_event *ev);
+extern void queue_wait_w_tmo(struct event_queue *q, struct queue_event *ev,
+                             int ticks);
+extern void queue_post(struct event_queue *q, long id, intptr_t data);
+#ifdef HAVE_EXTENDED_MESSAGING_AND_NAME
+extern void queue_enable_queue_send(struct event_queue *q,
+                                    struct queue_sender_list *send,
+                                    unsigned int owner_id);
+extern intptr_t queue_send(struct event_queue *q, long id, intptr_t data);
+extern void queue_reply(struct event_queue *q, intptr_t retval);
+extern bool queue_in_queue_send(struct event_queue *q);
+#endif /* HAVE_EXTENDED_MESSAGING_AND_NAME */
+extern bool queue_empty(const struct event_queue* q);
+extern bool queue_peek(struct event_queue *q, struct queue_event *ev);
+
+#define QPEEK_FILTER_COUNT_MASK (0xffu) /* 0x00=1 filter, 0xff=256 filters */
+#define QPEEK_FILTER_HEAD_ONLY  (1u << 8) /* Ignored if no filters */
+#define QPEEK_REMOVE_EVENTS     (1u << 9) /* Remove or discard events */
+extern bool queue_peek_ex(struct event_queue *q,
+                          struct queue_event *ev,
+                          unsigned int flags,
+                          const long (*filters)[2]);
+
+extern void queue_clear(struct event_queue* q);
+extern void queue_remove_from_head(struct event_queue *q, long id);
+extern int queue_count(const struct event_queue *q);
+extern int queue_broadcast(long id, intptr_t data);
+extern void init_queues(void);
+
+#endif /* QUEUE_H */
diff --git a/firmware/kernel/include/semaphore.h b/firmware/kernel/include/semaphore.h
new file mode 100644
index 0000000000..40e60bb88d
--- /dev/null
+++ b/firmware/kernel/include/semaphore.h
@@ -0,0 +1,40 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2002 by Björn Stenberg
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#ifndef SEMAPHORE_H
+#define SEMAPHORE_H
+
+#include "config.h"
+#include "thread.h"
+
+struct semaphore
+{
+    struct thread_entry *queue;         /* Waiter list */
+    int volatile count;                 /* # of waits remaining before unsignaled */
+    int max;                            /* maximum # of waits to remain signaled */
+    IF_COP( struct corelock cl; )       /* multiprocessor sync */
+};
+
+extern void semaphore_init(struct semaphore *s, int max, int start);
+extern int  semaphore_wait(struct semaphore *s, int timeout);
+extern void semaphore_release(struct semaphore *s);
+
+#endif /* SEMAPHORE_H */
diff --git a/firmware/kernel/include/thread.h b/firmware/kernel/include/thread.h
new file mode 100644
index 0000000000..9cc33b23ae
--- /dev/null
+++ b/firmware/kernel/include/thread.h
@@ -0,0 +1,387 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2002 by Ulf Ralberg
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#ifndef THREAD_H
+#define THREAD_H
+
+#include "config.h"
+#include <inttypes.h>
+#include <stddef.h>
+#include <stdbool.h>
+#include "gcc_extensions.h"
+#include "corelock.h"
+
+/* Priority scheduling (when enabled with HAVE_PRIORITY_SCHEDULING) works
+ * by giving high priority threads more CPU time than lower priority threads
+ * when they need it. Priority is differential such that the priority
+ * difference between a lower priority runnable thread and the highest priority
+ * runnable thread determines the amount of aging necessary for the lower
+ * priority thread to be scheduled in order to prevent starvation.
+ *
+ * If software playback codec pcm buffer is going down to critical, codec
+ * can gradually raise its own priority to override user interface and
+ * prevent playback skipping.
+ */
+#define PRIORITY_RESERVED_HIGH   0   /* Reserved */
+#define PRIORITY_RESERVED_LOW    32  /* Reserved */
+#define HIGHEST_PRIORITY         1   /* The highest possible thread priority */
+#define LOWEST_PRIORITY          31  /* The lowest possible thread priority */
+/* Realtime range reserved for threads that will not allow threads of lower
+ * priority to age and run (future expansion) */
+#define PRIORITY_REALTIME_1      1
+#define PRIORITY_REALTIME_2      2
+#define PRIORITY_REALTIME_3      3
+#define PRIORITY_REALTIME_4      4
+#define PRIORITY_REALTIME        4   /* Lowest realtime range */
+#define PRIORITY_BUFFERING       15  /* Codec buffering thread */
+#define PRIORITY_USER_INTERFACE  16  /* The main thread */
+#define PRIORITY_RECORDING       16  /* Recording thread */
+#define PRIORITY_PLAYBACK        16  /* Variable between this and MAX */
+#define PRIORITY_PLAYBACK_MAX    5   /* Maximum allowable playback priority */
+#define PRIORITY_SYSTEM          18  /* All other firmware threads */
+#define PRIORITY_BACKGROUND      20  /* Normal application threads */
+#define NUM_PRIORITIES           32
+#define PRIORITY_IDLE            32  /* Priority representative of no tasks */
+
+#define IO_PRIORITY_IMMEDIATE    0
+#define IO_PRIORITY_BACKGROUND   32
+
+
+#if CONFIG_CODEC == SWCODEC
+# ifdef HAVE_HARDWARE_CLICK
+#  define BASETHREADS  17
+# else
+#  define BASETHREADS  16
+# endif
+#else
+# define BASETHREADS   11
+#endif /* CONFIG_CODE == * */
+
+#ifndef TARGET_EXTRA_THREADS
+#define TARGET_EXTRA_THREADS 0
+#endif
+
+#define MAXTHREADS (BASETHREADS+TARGET_EXTRA_THREADS)
+/*
+ * We need more stack when we run under a host
+ * maybe more expensive C lib functions?
+ *
+ * simulator (possibly) doesn't simulate stack usage anyway but well ... */
+
+#if defined(HAVE_SDL_THREADS) || defined(__PCTOOL__)
+struct regs
+{
+    void *t;             /* OS thread */
+    void *told;          /* Last thread in slot (explained in thead-sdl.c) */
+    void *s;             /* Semaphore for blocking and wakeup */
+    void (*start)(void); /* Start function */
+};
+
+#define DEFAULT_STACK_SIZE 0x100 /* tiny, ignored anyway */
+#else
+#include "asm/thread.h"
+#endif /* HAVE_SDL_THREADS */
+
+/* NOTE: The use of the word "queue" may also refer to a linked list of
+   threads being maintained that are normally dealt with in FIFO order
+   and not necessarily kernel event_queue */
+enum
+{
+    /* States without a timeout must be first */
+    STATE_KILLED = 0,    /* Thread is killed (default) */
+    STATE_RUNNING,       /* Thread is currently running */
+    STATE_BLOCKED,       /* Thread is indefinitely blocked on a queue */
+    /* These states involve adding the thread to the tmo list */
+    STATE_SLEEPING,      /* Thread is sleeping with a timeout */
+    STATE_BLOCKED_W_TMO, /* Thread is blocked on a queue with a timeout */
+    /* Miscellaneous states */
+    STATE_FROZEN,        /* Thread is suspended and will not run until
+                            thread_thaw is called with its ID */
+    THREAD_NUM_STATES,
+    TIMEOUT_STATE_FIRST = STATE_SLEEPING,
+};
+
+#if NUM_CORES > 1
+/* Pointer value for name field to indicate thread is being killed. Using
+ * an alternate STATE_* won't work since that would interfere with operation
+ * while the thread is still running. */
+#define THREAD_DESTRUCT ((const char *)~(intptr_t)0)
+#endif
+
+/* Link information for lists thread is in */
+struct thread_entry; /* forward */
+struct thread_list
+{
+    struct thread_entry *prev; /* Previous thread in a list */
+    struct thread_entry *next; /* Next thread in a list */
+};
+
+#ifdef HAVE_PRIORITY_SCHEDULING
+struct blocker
+{
+    struct thread_entry * volatile thread; /* thread blocking other threads
+                                              (aka. object owner) */
+    int priority;                  /* highest priority waiter */
+    struct thread_entry * (*wakeup_protocol)(struct thread_entry *thread);
+};
+
+/* Choices of wakeup protocol */
+
+/* For transfer of object ownership by one thread to another thread by
+ * the owning thread itself (mutexes) */
+struct thread_entry *
+    wakeup_priority_protocol_transfer(struct thread_entry *thread);
+
+/* For release by owner where ownership doesn't change - other threads,
+ * interrupts, timeouts, etc. (mutex timeout, queues) */
+struct thread_entry *
+    wakeup_priority_protocol_release(struct thread_entry *thread);
+
+
+struct priority_distribution
+{
+    uint8_t  hist[NUM_PRIORITIES]; /* Histogram: Frequency for each priority */
+    uint32_t mask;                 /* Bitmask of hist entries that are not zero */
+};
+
+#endif /* HAVE_PRIORITY_SCHEDULING */
+
+/* Information kept in each thread slot
+ * members are arranged according to size - largest first - in order
+ * to ensure both alignment and packing at the same time.
+ */
+struct thread_entry
+{
+    struct regs context;       /* Register context at switch -
+                                  _must_ be first member */
+    uintptr_t *stack;          /* Pointer to top of stack */
+    const char *name;          /* Thread name */
+    long tmo_tick;             /* Tick when thread should be woken from
+                                  timeout -
+                                  states: STATE_SLEEPING/STATE_BLOCKED_W_TMO */
+    struct thread_list l;      /* Links for blocked/waking/running -
+                                  circular linkage in both directions */
+    struct thread_list tmo;    /* Links for timeout list -
+                                  Circular in reverse direction, NULL-terminated in
+                                  forward direction -
+                                  states: STATE_SLEEPING/STATE_BLOCKED_W_TMO */
+    struct thread_entry **bqp; /* Pointer to list variable in kernel
+                                  object where thread is blocked - used
+                                  for implicit unblock and explicit wake
+                                  states: STATE_BLOCKED/STATE_BLOCKED_W_TMO  */
+#ifdef HAVE_CORELOCK_OBJECT
+    struct corelock *obj_cl;   /* Object corelock where thead is blocked -
+                                  states: STATE_BLOCKED/STATE_BLOCKED_W_TMO */
+    struct corelock waiter_cl; /* Corelock for thread_wait */
+    struct corelock slot_cl;   /* Corelock to lock thread slot */
+    unsigned char core;        /* The core to which thread belongs */
+#endif
+    struct thread_entry *queue; /* List of threads waiting for thread to be
+                                  removed */
+#ifdef HAVE_WAKEUP_EXT_CB
+    void (*wakeup_ext_cb)(struct thread_entry *thread); /* Callback that
+                                  performs special steps needed when being
+                                  forced off of an object's wait queue that
+                                  go beyond the standard wait queue removal
+                                  and priority disinheritance */
+    /* Only enabled when using queue_send for now */
+#endif
+#if defined(HAVE_SEMAPHORE_OBJECTS) || \
+    defined(HAVE_EXTENDED_MESSAGING_AND_NAME) || \
+    NUM_CORES > 1
+    volatile intptr_t retval;  /* Return value from a blocked operation/
+                                  misc. use */
+#endif
+#ifdef HAVE_PRIORITY_SCHEDULING
+    /* Priority summary of owned objects that support inheritance */
+    struct blocker *blocker;   /* Pointer to blocker when this thread is blocked
+                                  on an object that supports PIP -
+                                  states: STATE_BLOCKED/STATE_BLOCKED_W_TMO  */
+    struct priority_distribution pdist; /* Priority summary of owned objects
+                                  that have blocked threads and thread's own
+                                  base priority */
+    int skip_count;            /* Number of times skipped if higher priority
+                                  thread was running */
+    unsigned char base_priority; /* Base priority (set explicitly during
+                                  creation or thread_set_priority) */
+    unsigned char priority;    /* Scheduled priority (higher of base or
+                                  all threads blocked by this one) */
+#endif
+    uint16_t id;               /* Current slot id */
+    unsigned short stack_size; /* Size of stack in bytes */
+    unsigned char state;       /* Thread slot state (STATE_*) */
+#ifdef HAVE_SCHEDULER_BOOSTCTRL
+    unsigned char cpu_boost;   /* CPU frequency boost flag */
+#endif
+#ifdef HAVE_IO_PRIORITY
+    unsigned char io_priority;
+#endif
+};
+
+/*** Macros for internal use ***/
+/* Thread ID, 16 bits = |VVVVVVVV|SSSSSSSS| */
+#define THREAD_ID_VERSION_SHIFT      8
+#define THREAD_ID_VERSION_MASK  0xff00
+#define THREAD_ID_SLOT_MASK     0x00ff
+#define THREAD_ID_INIT(n)       ((1u << THREAD_ID_VERSION_SHIFT) | (n))
+
+#ifdef HAVE_CORELOCK_OBJECT
+/* Operations to be performed just before stopping a thread and starting
+   a new one if specified before calling switch_thread */
+enum
+{
+    TBOP_CLEAR = 0,       /* No operation to do */
+    TBOP_UNLOCK_CORELOCK, /* Unlock a corelock variable */
+    TBOP_SWITCH_CORE,     /* Call the core switch preparation routine */
+};
+
+struct thread_blk_ops
+{
+    struct corelock *cl_p;    /* pointer to corelock */
+    unsigned char    flags;   /* TBOP_* flags */
+};
+#endif /* NUM_CORES > 1 */
+
+/* Information kept for each core
+ * Members are arranged for the same reason as in thread_entry
+ */
+struct core_entry
+{
+    /* "Active" lists - core is constantly active on these and are never
+       locked and interrupts do not access them */
+    struct thread_entry *running;  /* threads that are running (RTR) */
+    struct thread_entry *timeout;  /* threads that are on a timeout before
+                                      running again */
+    struct thread_entry *block_task; /* Task going off running list */
+#ifdef HAVE_PRIORITY_SCHEDULING
+    struct priority_distribution rtr; /* Summary of running and ready-to-run
+                                         threads */
+#endif
+    long next_tmo_check;           /* soonest time to check tmo threads */
+#ifdef HAVE_CORELOCK_OBJECT
+    struct thread_blk_ops blk_ops; /* operations to perform when
+                                      blocking a thread */
+    struct corelock rtr_cl;        /* Lock for rtr list */
+#endif /* NUM_CORES */
+};
+
+extern void yield(void);
+extern unsigned sleep(unsigned ticks);
+
+#ifdef HAVE_PRIORITY_SCHEDULING
+#define IF_PRIO(...)    __VA_ARGS__
+#define IFN_PRIO(...)
+#else
+#define IF_PRIO(...)
+#define IFN_PRIO(...)   __VA_ARGS__
+#endif
+
+void core_idle(void);
+void core_wake(IF_COP_VOID(unsigned int core));
+
+/* Initialize the scheduler */
+void init_threads(void) INIT_ATTR;
+
+/* Allocate a thread in the scheduler */
+#define CREATE_THREAD_FROZEN   0x00000001 /* Thread is frozen at create time */
+unsigned int create_thread(void (*function)(void),
+                           void* stack, size_t stack_size,
+                           unsigned flags, const char *name
+                           IF_PRIO(, int priority)
+                           IF_COP(, unsigned int core));
+
+/* Set and clear the CPU frequency boost flag for the calling thread */
+#ifdef HAVE_SCHEDULER_BOOSTCTRL
+void trigger_cpu_boost(void);
+void cancel_cpu_boost(void);
+#else
+#define trigger_cpu_boost() do { } while(0)
+#define cancel_cpu_boost() do { } while(0)
+#endif
+/* Return thread entry from id */
+struct thread_entry *thread_id_entry(unsigned int thread_id);
+/* Make a frozed thread runnable (when started with CREATE_THREAD_FROZEN).
+ * Has no effect on a thread not frozen. */
+void thread_thaw(unsigned int thread_id);
+/* Wait for a thread to exit */
+void thread_wait(unsigned int thread_id);
+/* Exit the current thread */
+void thread_exit(void) NORETURN_ATTR;
+#if defined(DEBUG) || defined(ROCKBOX_HAS_LOGF)
+#define ALLOW_REMOVE_THREAD
+/* Remove a thread from the scheduler */
+void remove_thread(unsigned int thread_id);
+#endif
+
+/* Switch to next runnable thread */
+void switch_thread(void);
+/* Blocks a thread for at least the specified number of ticks (0 = wait until
+ * next tick) */
+void sleep_thread(int ticks);
+/* Indefinitely blocks the current thread on a thread queue */
+void block_thread(struct thread_entry *current);
+/* Blocks the current thread on a thread queue until explicitely woken or
+ * the timeout is reached */
+void block_thread_w_tmo(struct thread_entry *current, int timeout);
+
+/* Return bit flags for thread wakeup */
+#define THREAD_NONE     0x0 /* No thread woken up (exclusive) */
+#define THREAD_OK       0x1 /* A thread was woken up */
+#define THREAD_SWITCH   0x2 /* Task switch recommended (one or more of
+                               higher priority than current were woken) */
+
+/* A convenience function for waking an entire queue of threads. */
+unsigned int thread_queue_wake(struct thread_entry **list);
+
+/* Wakeup a thread at the head of a list */
+unsigned int wakeup_thread(struct thread_entry **list);
+
+#ifdef HAVE_PRIORITY_SCHEDULING
+int thread_set_priority(unsigned int thread_id, int priority);
+int thread_get_priority(unsigned int thread_id);
+#endif /* HAVE_PRIORITY_SCHEDULING */
+#ifdef HAVE_IO_PRIORITY
+void thread_set_io_priority(unsigned int thread_id, int io_priority);
+int thread_get_io_priority(unsigned int thread_id);
+#endif /* HAVE_IO_PRIORITY */
+#if NUM_CORES > 1
+unsigned int switch_core(unsigned int new_core);
+#endif
+
+/* Return the id of the calling thread. */
+unsigned int thread_self(void);
+
+/* Return the thread_entry for the calling thread.
+ * INTERNAL: Intended for use by kernel and not for programs. */
+struct thread_entry* thread_self_entry(void);
+
+/* Debugging info - only! */
+int thread_stack_usage(const struct thread_entry *thread);
+#if NUM_CORES > 1
+int idle_stack_usage(unsigned int core);
+#endif
+void thread_get_name(char *buffer, int size,
+                     struct thread_entry *thread);
+#ifdef RB_PROFILE
+void profile_thread(void);
+#endif
+
+#endif /* THREAD_H */
diff --git a/firmware/kernel/include/tick.h b/firmware/kernel/include/tick.h
new file mode 100644
index 0000000000..9810f4a1e5
--- /dev/null
+++ b/firmware/kernel/include/tick.h
@@ -0,0 +1,67 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2002 by Björn Stenberg
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#ifndef TICK_H
+#define TICK_H
+
+#include "config.h"
+#include "system.h" /* for NULL */
+extern void init_tick(void);
+
+#define HZ      100 /* number of ticks per second */
+
+#define MAX_NUM_TICK_TASKS 8
+
+/* global tick variable */
+#if defined(CPU_PP) && defined(BOOTLOADER) && \
+    !defined(HAVE_BOOTLOADER_USB_MODE)
+/* We don't enable interrupts in the PP bootloader unless USB mode is
+   enabled for it, so we need to fake the current_tick variable */
+#define current_tick (signed)(USEC_TIMER/10000)
+
+static inline void call_tick_tasks(void)
+{
+}
+#else
+extern volatile long current_tick;
+
+/* inline helper for implementing target interrupt handler */
+static inline void call_tick_tasks(void)
+{
+    extern void (*tick_funcs[MAX_NUM_TICK_TASKS+1])(void);
+    void (**p)(void) = tick_funcs;
+    void (*fn)(void);
+
+    current_tick++;
+
+    for(fn = *p; fn != NULL; fn = *(++p))
+    {
+        fn();
+    }
+}
+#endif
+
+/* implemented in target tree */
+extern void tick_start(unsigned int interval_in_ms) INIT_ATTR;
+
+extern int tick_add_task(void (*f)(void));
+extern int tick_remove_task(void (*f)(void));
+
+#endif /* TICK_H */
diff --git a/firmware/kernel/include/timeout.h b/firmware/kernel/include/timeout.h
new file mode 100644
index 0000000000..0b7c52ba4c
--- /dev/null
+++ b/firmware/kernel/include/timeout.h
@@ -0,0 +1,46 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2002 by Björn Stenberg
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#ifndef _KERNEL_H_
+#define _KERNEL_H_
+
+#include "config.h"
+
+struct timeout;
+
+/* timeout callback type
+ * tmo - pointer to struct timeout associated with event
+ * return next interval or <= 0 to stop event
+ */
+#define MAX_NUM_TIMEOUTS 8
+typedef int (* timeout_cb_type)(struct timeout *tmo);
+
+struct timeout
+{
+    timeout_cb_type callback;/* callback - returning false cancels */
+    intptr_t        data;    /* data passed to callback */
+    long            expires; /* expiration tick */
+};
+
+void timeout_register(struct timeout *tmo, timeout_cb_type callback,
+                      int ticks, intptr_t data);
+void timeout_cancel(struct timeout *tmo);
+
+#endif /* _KERNEL_H_ */