firmware/kernel.h

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2002 by Björn Stenberg
  11  *
  12  * All files in this archive are subject to the GNU General Public License.
  13  * See the file COPYING in the source tree root for full license agreement.
  14  *
  15  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  16  * KIND, either express or implied.
  17  *
  18  ****************************************************************************/
  19 #ifndef _KERNEL_H_
  20 #define _KERNEL_H_
  21
  22 #include <stdbool.h>
  23
  24 /* wrap-safe macros for tick comparison */
  25 #define TIME_AFTER(a,b)         ((long)(b) - (long)(a) < 0)
  26 #define TIME_BEFORE(a,b)        TIME_AFTER(b,a)
  27
  28 #define HZ      100 /* number of ticks per second */
  29
  30 #define MAX_NUM_TICK_TASKS 4
  31
  32 #define QUEUE_LENGTH 16 /* MUST be a power of 2 */
  33 #define QUEUE_LENGTH_MASK (QUEUE_LENGTH - 1)
  34
  35 /* System defined message ID's */
  36 #define SYS_USB_CONNECTED         -1
  37 #define SYS_USB_CONNECTED_ACK     -2
  38 #define SYS_USB_DISCONNECTED      -3
  39 #define SYS_USB_DISCONNECTED_ACK  -4
  40
  41 struct event
  42 {
  43     int id;
  44     void *data;
  45 };
  46
  47 struct event_queue
  48 {
  49     struct event events[QUEUE_LENGTH];
  50     unsigned int read;
  51     unsigned int write;
  52 };
  53
  54 struct mutex
  55 {
  56     bool locked;
  57 };
  58
  59 /* global tick variable */
  60 extern long current_tick;
  61
  62 /* kernel functions */
  63 extern void kernel_init(void);
  64 extern void yield(void);
  65 extern void sleep(int ticks);
  66 int set_irq_level(int level);
  67 int tick_add_task(void (*f)(void));
  68 int tick_remove_task(void (*f)(void));
  69
  70 extern void queue_init(struct event_queue *q);
  71 extern void queue_wait(struct event_queue *q, struct event *ev);
  72 extern void queue_post(struct event_queue *q, int id, void *data);
  73 extern bool queue_empty(struct event_queue* q);
  74 extern int queue_broadcast(int id, void *data);
  75
  76 extern void mutex_init(struct mutex *m);
  77 extern void mutex_lock(struct mutex *m);
  78 extern void mutex_unlock(struct mutex *m);
  79
  80 #endif