Subversion Repositories openrisc_2011-10-31

/*

 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without modification,

 * are permitted provided that the following conditions are met:

 *

 * 1. Redistributions of source code must retain the above copyright notice,

 *    this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright notice,

 *    this list of conditions and the following disclaimer in the documentation

 *    and/or other materials provided with the distribution.

 * 3. The name of the author may not be used to endorse or promote products

 *    derived from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED

 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT

 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT

 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING

 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY

 * OF SUCH DAMAGE.

 *

 * This file is part of the lwIP TCP/IP stack.

 *

 * Author: Adam Dunkels <adam@sics.se>

 *

 */

#ifndef __LWIP_SYS_H__

#define __LWIP_SYS_H__

#include "lwip/opt.h"

#ifdef __cplusplus

extern "C" {

#endif

#if NO_SYS

/* For a totally minimal and standalone system, we provide null

   definitions of the sys_ functions. */

typedef u8_t sys_sem_t;

typedef u8_t sys_mbox_t;

typedef u8_t sys_prot_t;

struct sys_timeo {u8_t dummy;};

#define sys_init()

#define sys_timeout(m,h,a)

#define sys_untimeout(m,a)

#define sys_sem_new(c) c

#define sys_sem_signal(s)

#define sys_sem_wait(s)

#define sys_sem_wait_timeout(s,t)

#define sys_arch_sem_wait(s,t)

#define sys_sem_free(s)

#define sys_mbox_new(s) 0

#define sys_mbox_fetch(m,d)

#define sys_mbox_tryfetch(m,d)

#define sys_mbox_post(m,d)

#define sys_mbox_trypost(m,d)

#define sys_mbox_free(m)

#define sys_thread_new(n,t,a,s,p)

#else /* NO_SYS */

/** Return code for timeouts from sys_arch_mbox_fetch and sys_arch_sem_wait */

#define SYS_ARCH_TIMEOUT 0xffffffffUL

/* sys_mbox_tryfetch returns SYS_MBOX_EMPTY if appropriate.

 * For now we use the same magic value, but we allow this to change in future.

 */

#define SYS_MBOX_EMPTY SYS_ARCH_TIMEOUT

#include "lwip/err.h"

#include "arch/sys_arch.h"

typedef void (* sys_timeout_handler)(void *arg);

struct sys_timeo {

  struct sys_timeo *next;

  u32_t time;

  sys_timeout_handler h;

  void *arg;

};

struct sys_timeouts {

  struct sys_timeo *next;

};

/* sys_init() must be called before anthing else. */

void sys_init(void);

/*

 * sys_timeout():

 *

 * Schedule a timeout a specified amount of milliseconds in the

 * future. When the timeout occurs, the specified timeout handler will

 * be called. The handler will be passed the "arg" argument when

 * called.

 *

 */

void sys_timeout(u32_t msecs, sys_timeout_handler h, void *arg);

void sys_untimeout(sys_timeout_handler h, void *arg);

struct sys_timeouts *sys_arch_timeouts(void);

/* Semaphore functions. */

sys_sem_t sys_sem_new(u8_t count);

void sys_sem_signal(sys_sem_t sem);

u32_t sys_arch_sem_wait(sys_sem_t sem, u32_t timeout);

void sys_sem_free(sys_sem_t sem);

void sys_sem_wait(sys_sem_t sem);

int sys_sem_wait_timeout(sys_sem_t sem, u32_t timeout);

/* Time functions. */

#ifndef sys_msleep

void sys_msleep(u32_t ms); /* only has a (close to) 1 jiffy resolution. */

#endif

#ifndef sys_jiffies

u32_t sys_jiffies(void); /* since power up. */

#endif

/* Mailbox functions. */

sys_mbox_t sys_mbox_new(int size);

void sys_mbox_post(sys_mbox_t mbox, void *msg);

err_t sys_mbox_trypost(sys_mbox_t mbox, void *msg);

u32_t sys_arch_mbox_fetch(sys_mbox_t mbox, void **msg, u32_t timeout);

#ifndef sys_arch_mbox_tryfetch /* Allow port to override with a macro */

u32_t sys_arch_mbox_tryfetch(sys_mbox_t mbox, void **msg);

#endif

/* For now, we map straight to sys_arch implementation. */

#define sys_mbox_tryfetch(mbox, msg) sys_arch_mbox_tryfetch(mbox, msg)

void sys_mbox_free(sys_mbox_t mbox);

void sys_mbox_fetch(sys_mbox_t mbox, void **msg);

/* Thread functions. */

sys_thread_t sys_thread_new(char *name, void (* thread)(void *arg), void *arg, int stacksize, int prio);

/* The following functions are used only in Unix code, and

   can be omitted when porting the stack. */

/* Returns the current time in microseconds. */

unsigned long sys_now(void);

#endif /* NO_SYS */

/* Critical Region Protection */

/* These functions must be implemented in the sys_arch.c file.

   In some implementations they can provide a more light-weight protection

   mechanism than using semaphores. Otherwise semaphores can be used for

   implementation */

#ifndef SYS_ARCH_PROTECT

/** SYS_LIGHTWEIGHT_PROT

 * define SYS_LIGHTWEIGHT_PROT in lwipopts.h if you want inter-task protection

 * for certain critical regions during buffer allocation, deallocation and memory

 * allocation and deallocation.

 */

#if SYS_LIGHTWEIGHT_PROT

/** SYS_ARCH_DECL_PROTECT

 * declare a protection variable. This macro will default to defining a variable of

 * type sys_prot_t. If a particular port needs a different implementation, then

 * this macro may be defined in sys_arch.h.

 */

#define SYS_ARCH_DECL_PROTECT(lev) sys_prot_t lev

/** SYS_ARCH_PROTECT

 * Perform a "fast" protect. This could be implemented by

 * disabling interrupts for an embedded system or by using a semaphore or

 * mutex. The implementation should allow calling SYS_ARCH_PROTECT when

 * already protected. The old protection level is returned in the variable

 * "lev". This macro will default to calling the sys_arch_protect() function

 * which should be implemented in sys_arch.c. If a particular port needs a

 * different implementation, then this macro may be defined in sys_arch.h

 */

#define SYS_ARCH_PROTECT(lev) lev = sys_arch_protect()

/** SYS_ARCH_UNPROTECT

 * Perform a "fast" set of the protection level to "lev". This could be

 * implemented by setting the interrupt level to "lev" within the MACRO or by

 * using a semaphore or mutex.  This macro will default to calling the

 * sys_arch_unprotect() function which should be implemented in

 * sys_arch.c. If a particular port needs a different implementation, then

 * this macro may be defined in sys_arch.h

 */

#define SYS_ARCH_UNPROTECT(lev) sys_arch_unprotect(lev)

sys_prot_t sys_arch_protect(void);

void sys_arch_unprotect(sys_prot_t pval);

#else

#define SYS_ARCH_DECL_PROTECT(lev)

#define SYS_ARCH_PROTECT(lev)

#define SYS_ARCH_UNPROTECT(lev)

#endif /* SYS_LIGHTWEIGHT_PROT */

#endif /* SYS_ARCH_PROTECT */

/*

 * Macros to set/get and increase/decrease variables in a thread-safe way.

 * Use these for accessing variable that are used from more than one thread.

 */

#ifndef SYS_ARCH_INC

#define SYS_ARCH_INC(var, val) do { \

                                SYS_ARCH_DECL_PROTECT(old_level); \

                                SYS_ARCH_PROTECT(old_level); \

                                var += val; \

                                SYS_ARCH_UNPROTECT(old_level); \

                              } while(0)

#endif /* SYS_ARCH_INC */

#ifndef SYS_ARCH_DEC

#define SYS_ARCH_DEC(var, val) do { \

                                SYS_ARCH_DECL_PROTECT(old_level); \

                                SYS_ARCH_PROTECT(old_level); \

                                var -= val; \

                                SYS_ARCH_UNPROTECT(old_level); \

                              } while(0)

#endif /* SYS_ARCH_DEC */

#ifndef SYS_ARCH_GET

#define SYS_ARCH_GET(var, ret) do { \

                                SYS_ARCH_DECL_PROTECT(old_level); \

                                SYS_ARCH_PROTECT(old_level); \

                                ret = var; \

                                SYS_ARCH_UNPROTECT(old_level); \

                              } while(0)

#endif /* SYS_ARCH_GET */

#ifndef SYS_ARCH_SET

#define SYS_ARCH_SET(var, val) do { \

                                SYS_ARCH_DECL_PROTECT(old_level); \

                                SYS_ARCH_PROTECT(old_level); \

                                var = val; \

                                SYS_ARCH_UNPROTECT(old_level); \

                              } while(0)

#endif /* SYS_ARCH_SET */

#ifdef __cplusplus

}

#endif

#endif /* __LWIP_SYS_H__ */