1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
|
//==========================================================================
//
// devs/wallclock/wallclock.cxx
//
// Wallclock base
//
//==========================================================================
// ####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002, 2009 Free Software Foundation, Inc.
//
// eCos 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 or (at your option) any later
// version.
//
// eCos is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License
// along with eCos; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
//
// As a special exception, if other files instantiate templates or use
// macros or inline functions from this file, or you compile this file
// and link it with other works to produce a work based on this file,
// this file does not by itself cause the resulting work to be covered by
// the GNU General Public License. However the source code for this file
// must still be made available in accordance with section (3) of the GNU
// General Public License v2.
//
// This exception does not invalidate any other reasons why a work based
// on this file might be covered by the GNU General Public License.
// -------------------------------------------
// ####ECOSGPLCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s): jskov
// Contributors: jskov
// Date: 2000-03-28
// Purpose: Wallclock base driver
// Description: This provides a generic wallclock base driver which
// relies on sub-drivers to provide the interface functions
// to the hardware device (see wallclock.hxx for details).
//
// The driver can be configured to run in one of two modes:
// init-get mode:
// In this mode, the hardware driver only needs to
// implement a function to read the hardware clock
// and a (possibly empty) init function which makes
// sure the hardware clock is properly initialized.
// While the driver in this mode has a smaller memory
// foot-print, it does not support battery-backed up
// clocks.
//
// set-get mode:
// Requires both set and get functions for the hardware
// device. While bigger, it allows support of
// battery-backed up clocks.
//
//
//####DESCRIPTIONEND####
//
//==========================================================================
#include <pkgconf/wallclock.h> // Wallclock device config
#include <cyg/infra/cyg_type.h> // Common type definitions and support
#include <cyg/hal/drv_api.h> // Driver API
#include <cyg/io/wallclock.hxx> // The WallClock API
//-----------------------------------------------------------------------------
// Local static variables
static Cyg_WallClock wallclock_instance CYGBLD_ATTRIB_INIT_PRI( CYG_INIT_DEV_WALLCLOCK );
#ifndef CYGSEM_WALLCLOCK_SET_GET_MODE
static cyg_uint32 epoch_ticks;
static cyg_uint32 epoch_time_stamp;
#endif
static cyg_drv_mutex_t wallclock_lock;
Cyg_WallClock *Cyg_WallClock::wallclock;
//-----------------------------------------------------------------------------
// Constructor
Cyg_WallClock::Cyg_WallClock()
{
// install instance pointer
wallclock = &wallclock_instance;
// Initialize lock used for mutually exclusive access to hardware
cyg_drv_mutex_init(&wallclock_lock);
// Always allow low-level driver to initialize clock, even though it
// may not be necessary for set-get mode.
init_hw_seconds();
}
//-----------------------------------------------------------------------------
// Returns the number of seconds elapsed since 1970-01-01 00:00:00.
// This may involve reading the hardware, so it may take anything up to
// a second to complete.
cyg_uint32 Cyg_WallClock::get_current_time()
{
cyg_uint32 res;
while (!cyg_drv_mutex_lock(&wallclock_lock));
#ifdef CYGSEM_WALLCLOCK_SET_GET_MODE
res = get_hw_seconds();
#else
res = epoch_time_stamp + get_hw_seconds() - epoch_ticks;
#endif
cyg_drv_mutex_unlock(&wallclock_lock);
return res;
}
//-----------------------------------------------------------------------------
// Sets the clock. Argument is seconds elapsed since 1970-01-01 00:00:00.
// This may involve reading or writing to the hardware, so it may take
// anything up to a second to complete.
void Cyg_WallClock::set_current_time( cyg_uint32 time_stamp )
{
while (!cyg_drv_mutex_lock(&wallclock_lock));
#ifdef CYGSEM_WALLCLOCK_SET_GET_MODE
set_hw_seconds(time_stamp);
#else
epoch_time_stamp = time_stamp;
epoch_ticks = get_hw_seconds();
#endif
cyg_drv_mutex_unlock(&wallclock_lock);
}
//-----------------------------------------------------------------------------
// End of devs/wallclock/wallclock.cxx
|