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diff --git a/firmware/kernel/thread-internal.h b/firmware/kernel/thread-internal.h
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+/***************************************************************************
+ * __________ __ ___.
+ * 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"
+
+/*
+ * 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 */
+
+#ifdef CPU_PP
+#ifdef HAVE_CORELOCK_OBJECT
+/* 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 */
+void corelock_init(struct corelock *cl);
+void corelock_lock(struct corelock *cl);
+int corelock_try_lock(struct corelock *cl);
+void corelock_unlock(struct corelock *cl);
+#endif /* HAVE_CORELOCK_OBJECT */
+#endif /* CPU_PP */
+
+/* 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 */
+};
+
+#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)
+#endif /* HAVE_CORELOCK_OBJECT */
+
+#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 */
+};
+
+#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 */