Mercurial > nand-ecoscentric

comparison packages/devs/watchdog/current/src/emulate.cxx @ 0:3111d98ba7b3 ecos-v1_1-release

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Initial commit of eCos version 1.1
author jlarmour
date Tue, 11 May 1999 11:16:07 +0000
parents
children 443894e2e912
comparison
equal deleted inserted replaced
-1:000000000000 0:3111d98ba7b3
1 //==========================================================================
2 //
3 // watchdog/emulate.cxx
4 //
5 // Watchdog implementation emulation
6 //
7 //==========================================================================
8 //####COPYRIGHTBEGIN####
9 //
10 // -------------------------------------------
11 // The contents of this file are subject to the Cygnus eCos Public License
12 // Version 1.0 (the "License"); you may not use this file except in
13 // compliance with the License. You may obtain a copy of the License at
14 // http://sourceware.cygnus.com/ecos
15 //
16 // Software distributed under the License is distributed on an "AS IS"
17 // basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
18 // License for the specific language governing rights and limitations under
19 // the License.
20 //
21 // The Original Code is eCos - Embedded Cygnus Operating System, released
22 // September 30, 1998.
23 //
24 // The Initial Developer of the Original Code is Cygnus. Portions created
25 // by Cygnus are Copyright (C) 1998 Cygnus Solutions. All Rights Reserved.
26 // -------------------------------------------
27 //
28 //####COPYRIGHTEND####
29 //==========================================================================
30 //#####DESCRIPTIONBEGIN####
31 //
32 // Author(s): nickg
33 // Contributors: nickg
34 // Date: 1998-07-29
35 // Purpose: Watchdog class implementation
36 // Description: Contains an implementation of the Watchdog class for use
37 // when there is no hardware watchdog timer. Instead it is
38 // emulated using an Alarm object.
39 //
40 //####DESCRIPTIONEND####
41 //
42 //==========================================================================
43
44 #include <pkgconf/watchdog.h> // watchdog configuration file
45
46 #ifdef CYGIMP_WATCHDOG_EMULATE
47
48 #include <cyg/kernel/ktypes.h> // base kernel types
49 #include <cyg/infra/cyg_trac.h> // tracing macros
50 #include <cyg/infra/cyg_ass.h> // assertion macros
51 #include <cyg/kernel/instrmnt.h> // instrumentation
52
53 #include <cyg/kernel/clock.hxx> // clock and alarm
54 #include <cyg/kernel/sched.hxx> // scheduler
55
56 #include <cyg/devs/watchdog.hxx> // my header
57
58 #include <cyg/kernel/sched.inl> // scheduler inlines
59
60 // -------------------------------------------------------------------------
61 // Forward definitions
62
63 static cyg_alarm_fn watchdog_alarm;
64
65 // -------------------------------------------------------------------------
66 // Statics
67
68 // A static pointer to the single system defined watchdog device.
69 Cyg_Watchdog Cyg_Watchdog::watchdog;
70
71 static Cyg_Alarm alarm( Cyg_Clock::real_time_clock, watchdog_alarm, 0 );
72
73 // One second's worth of ticks.
74 static cyg_tick_count one_sec;
75
76 // -------------------------------------------------------------------------
77 // Constructor
78
79 Cyg_Watchdog::Cyg_Watchdog()
80 {
81 CYG_REPORT_FUNCTION();
82
83 action_list = 0;
84
85 Cyg_Clock::cyg_resolution res = Cyg_Clock::real_time_clock->get_resolution();
86
87 one_sec = ( res.divisor * 1000000000LL ) / res.dividend ;
88
89 CYG_REPORT_RETURN();
90 }
91
92 // -------------------------------------------------------------------------
93 // Start the watchdog running.
94
95 void Cyg_Watchdog::start()
96 {
97 CYG_REPORT_FUNCTION();
98
99 Cyg_Clock::cyg_resolution res = Cyg_Clock::real_time_clock->get_resolution();
100
101 // Set alarm to a one second single-shot trigger
102 alarm.initialize( Cyg_Clock::real_time_clock->current_value() + one_sec, 0 );
103
104 CYG_REPORT_RETURN();
105 }
106
107 // -------------------------------------------------------------------------
108 // Reset watchdog timer. This needs to be called regularly to prevent
109 // the watchdog firing.
110
111 void Cyg_Watchdog::reset()
112 {
113 CYG_REPORT_FUNCTION();
114
115 Cyg_Clock::cyg_resolution res = Cyg_Clock::real_time_clock->get_resolution();
116
117 Cyg_Scheduler::lock();
118
119 // Set alarm to a one second single-shot trigger
120 alarm.initialize( Cyg_Clock::real_time_clock->current_value() + one_sec, 0 );
121
122 Cyg_Scheduler::unlock();
123
124 CYG_REPORT_RETURN();
125 }
126
127 // -------------------------------------------------------------------------
128 // Trigger the watchdog as if the timer had expired.
129
130 void Cyg_Watchdog::trigger()
131 {
132 CYG_REPORT_FUNCTION();
133
134 Cyg_Scheduler::lock();
135
136 // Disable alarm just in case
137 alarm.disable();
138
139 Cyg_Watchdog_Action *act = action_list;
140
141 while( 0 != act )
142 {
143 act->action( act->data );
144
145 act = act->next;
146 }
147
148 Cyg_Scheduler::unlock();
149
150 CYG_REPORT_RETURN();
151 }
152
153 // -------------------------------------------------------------------------
154 // Register an action routine that will be called when the timer
155 // triggers.
156
157 void Cyg_Watchdog::install_action( Cyg_Watchdog_Action *action )
158 {
159 CYG_REPORT_FUNCTION();
160
161 Cyg_Scheduler::lock();
162
163 action->next = action_list;
164 action_list = action;
165
166 Cyg_Scheduler::unlock();
167
168 CYG_REPORT_RETURN();
169 }
170
171 // -------------------------------------------------------------------------
172 // Deregister a previously registered action routine.
173
174 void Cyg_Watchdog::uninstall_action( Cyg_Watchdog_Action *action )
175 {
176 CYG_REPORT_FUNCTION();
177
178 Cyg_Scheduler::lock();
179
180 Cyg_Watchdog_Action **act_ptr = &action_list;
181
182 while( 0 != *act_ptr )
183 {
184 Cyg_Watchdog_Action *a = *act_ptr;
185
186 if( a == action )
187 {
188 *act_ptr = a->next;
189 break;
190 }
191 act_ptr = &a->next;
192 }
193
194 Cyg_Scheduler::unlock();
195
196 CYG_REPORT_RETURN();
197 }
198
199 // -------------------------------------------------------------------------
200 // Alarm function
201
202 void watchdog_alarm( Cyg_Alarm *a, CYG_ADDRWORD data)
203 {
204 CYG_REPORT_FUNCTION();
205
206 Cyg_Watchdog::watchdog.trigger();
207 }
208
209 #endif // CYGIMP_WATCHDOG_EMULATE
210 // -------------------------------------------------------------------------
211 // EOF watchdog/emulate.cxx