Files
foc/l4/pkg/l4sys/include/__timeout.h
2013-01-11 17:00:47 +01:00

278 lines
6.9 KiB
C

/**
* \internal
* \file
* \brief Timeout definitions.
*/
/*
* (c) 2008-2009 Adam Lackorzynski <adam@os.inf.tu-dresden.de>,
* Alexander Warg <warg@os.inf.tu-dresden.de>,
* Torsten Frenzel <frenzel@os.inf.tu-dresden.de>
* economic rights: Technische Universität Dresden (Germany)
*
* This file is part of TUD:OS and distributed under the terms of the
* GNU General Public License 2.
* Please see the COPYING-GPL-2 file for details.
*
* As a special exception, you may use this file as part of a free software
* library without restriction. Specifically, if other files instantiate
* templates or use macros or inline functions from this file, or you compile
* this file and link it with other files to produce an executable, this
* file does not by itself cause the resulting executable to be covered by
* the GNU General Public License. This exception does not however
* invalidate any other reasons why the executable file might be covered by
* the GNU General Public License.
*/
#ifndef L4_SYS_TIMEOUT_H__
#define L4_SYS_TIMEOUT_H__
#include <l4/sys/l4int.h>
/**
* \defgroup l4_timeout_api Timeouts
* \ingroup l4_ipc_api
* \brief All kinds of timeouts and time related functions.
*/
/**
* \brief Basic timeout specification.
* \ingroup l4_timeout_api
*
* Basically a floating point number with 10 bits mantissa and
* 5 bits exponent (t = m*2^e).
*
* The timeout can also specify an absolute point in time (bit 16 == 1).
*/
typedef struct l4_timeout_s {
l4_uint16_t t; /**< timeout value */
} __attribute__((packed)) l4_timeout_s;
/**
* \brief Timeout pair.
* \ingroup l4_timeout_api
*
* For IPC there are usually a send and a receive timeout.
* So this structure contains a pair of timeouts.
*/
typedef union l4_timeout_t {
l4_uint32_t raw; /**< raw value */
struct
{
#ifdef __BIG_ENDIAN__
l4_timeout_s snd; /**< send timeout */
l4_timeout_s rcv; /**< receive timeout */
#else
l4_timeout_s rcv; /**< receive timeout */
l4_timeout_s snd; /**< send timeout */
#endif
} p; /**< combined timeout */
} l4_timeout_t;
/**
* \brief Timeout constants.
* \ingroup l4_timeout_api
*/
/*@{*/
#define L4_IPC_TIMEOUT_0 ((l4_timeout_s){0x0400}) /**< 0 timeout */
#define L4_IPC_TIMEOUT_NEVER ((l4_timeout_s){0}) /**< never timeout */
#define L4_IPC_NEVER_INITIALIZER {0} /**< never timeout, init */
#define L4_IPC_NEVER ((l4_timeout_t){0}) /**< never timeout */
#define L4_IPC_RECV_TIMEOUT_0 ((l4_timeout_t){0x00000400}) /**< 0 receive timeout */
#define L4_IPC_SEND_TIMEOUT_0 ((l4_timeout_t){0x04000000}) /**< 0 send timeout */
#define L4_IPC_BOTH_TIMEOUT_0 ((l4_timeout_t){0x04000400}) /**< 0 receive and send timeout */
/*@}*/
/**
* \brief Intervals of validity for absolute timeouts
* \ingroup l4_timeout_api
*
* Times are actually 2^x values (e.g. 2ms -> 2048µs)
*/
enum l4_timeout_abs_validity {
L4_TIMEOUT_ABS_V1_ms = 0,
L4_TIMEOUT_ABS_V2_ms,
L4_TIMEOUT_ABS_V4_ms,
L4_TIMEOUT_ABS_V8_ms, /* 5 */
L4_TIMEOUT_ABS_V16_ms,
L4_TIMEOUT_ABS_V32_ms,
L4_TIMEOUT_ABS_V64_ms,
L4_TIMEOUT_ABS_V128_ms,
L4_TIMEOUT_ABS_V256_ms, /* 10 */
L4_TIMEOUT_ABS_V512_ms,
L4_TIMEOUT_ABS_V1_s,
L4_TIMEOUT_ABS_V2_s,
L4_TIMEOUT_ABS_V4_s,
L4_TIMEOUT_ABS_V8_s,
L4_TIMEOUT_ABS_V16_s,
L4_TIMEOUT_ABS_V32_s,
};
/**
* \brief Get relative timeout consisting of mantissa and exponent.
* \ingroup l4_timeout_api
*
* \param man Mantissa of timeout
* \param exp Exponent of timeout
*
* \return timeout value
*/
L4_INLINE
l4_timeout_s l4_timeout_rel(unsigned man, unsigned exp) L4_NOTHROW;
/**
* \brief Convert explicit timeout values to l4_timeout_t type.
* \ingroup l4_timeout_api
*
* \param snd_man Mantissa of send timeout.
* \param snd_exp Exponent of send timeout.
* \param rcv_man Mantissa of receive timeout.
* \param rcv_exp Exponent of receive timeout.
*/
L4_INLINE
l4_timeout_t l4_ipc_timeout(unsigned snd_man, unsigned snd_exp,
unsigned rcv_man, unsigned rcv_exp) L4_NOTHROW;
/**
* \brief Combine send and receive timeout in a timeout.
* \ingroup l4_timeout_api
*
* \param snd Send timeout
* \param rcv Receive timeout
*
* \return L4 timeout
*/
L4_INLINE
l4_timeout_t l4_timeout(l4_timeout_s snd, l4_timeout_s rcv) L4_NOTHROW;
/**
* \brief Set send timeout in given to timeout.
* \ingroup l4_timeout_api
*
* \param snd Send timeout
* \retval to L4 timeout
*/
L4_INLINE
void l4_snd_timeout(l4_timeout_s snd, l4_timeout_t *to) L4_NOTHROW;
/**
* \brief Set receive timeout in given to timeout.
* \ingroup l4_timeout_api
*
* \param rcv Receive timeout
* \retval to L4 timeout
*/
L4_INLINE
void l4_rcv_timeout(l4_timeout_s rcv, l4_timeout_t *to) L4_NOTHROW;
/**
* \brief Get clock value of out timeout.
* \ingroup l4_timeout_api
*
* \param to L4 timeout
*
* \return Clock value
*/
L4_INLINE
l4_kernel_clock_t l4_timeout_rel_get(l4_timeout_s to) L4_NOTHROW;
/**
* \brief Return whether the given timeout is absolute or not.
* \ingroup l4_timeout_api
*
* \param to L4 timeout
*
* \return != 0 if absolute, 0 if relative
*/
L4_INLINE
unsigned l4_timeout_is_absolute(l4_timeout_s to) L4_NOTHROW;
/**
* \brief Get clock value for a clock + a timeout.
* \ingroup l4_timeout_api
*
* \param cur Clock value
* \param to L4 timeout
*
* \return Clock sum
*/
L4_INLINE
l4_kernel_clock_t l4_timeout_get(l4_kernel_clock_t cur, l4_timeout_s to) L4_NOTHROW;
/*
* Implementation
*/
L4_INLINE
l4_timeout_t l4_ipc_timeout(unsigned snd_man, unsigned snd_exp,
unsigned rcv_man, unsigned rcv_exp) L4_NOTHROW
{
l4_timeout_t t;
t.p.snd.t = (snd_man & 0x3ff) | ((snd_exp << 10) & 0x7c00);
t.p.rcv.t = (rcv_man & 0x3ff) | ((rcv_exp << 10) & 0x7c00);
return t;
}
L4_INLINE
l4_timeout_t l4_timeout(l4_timeout_s snd, l4_timeout_s rcv) L4_NOTHROW
{
l4_timeout_t t;
t.p.snd = snd;
t.p.rcv = rcv;
return t;
}
L4_INLINE
void l4_snd_timeout(l4_timeout_s snd, l4_timeout_t *to) L4_NOTHROW
{
to->p.snd = snd;
}
L4_INLINE
void l4_rcv_timeout(l4_timeout_s rcv, l4_timeout_t *to) L4_NOTHROW
{
to->p.rcv = rcv;
}
L4_INLINE
l4_timeout_s l4_timeout_rel(unsigned man, unsigned exp) L4_NOTHROW
{
return (l4_timeout_s){(l4_uint16_t)((man & 0x3ff) | ((exp << 10) & 0x7c00))};
}
L4_INLINE
l4_kernel_clock_t l4_timeout_rel_get(l4_timeout_s to) L4_NOTHROW
{
if (to.t == 0)
return ~0ULL;
return (l4_kernel_clock_t)(to.t & 0x3ff) << ((to.t >> 10) & 0x1f);
}
L4_INLINE
unsigned l4_timeout_is_absolute(l4_timeout_s to) L4_NOTHROW
{
return to.t & 0x8000;
}
L4_INLINE
l4_kernel_clock_t l4_timeout_get(l4_kernel_clock_t cur, l4_timeout_s to) L4_NOTHROW
{
if (l4_timeout_is_absolute(to))
return 0; /* We cannot retrieve the value ... */
else
return cur + l4_timeout_rel_get(to);
}
#endif