source: rtems/c/src/lib/libcpu/mips64orion/clock/ckinit.c @ c8f3e82

Last change on this file since c8f3e82 was 0dd1d44, checked in by Joel Sherrill <joel.sherrill@…>, on Jan 11, 2000 at 5:34:20 PM

Removed old hack of using Configuration Table entry ticks_per_timeslice
being set to 0 to indicate that there should be no Clock Tick. This
was used by the Timing Tests to avoid clock tick overhead perturbing
execution times. Now the Timing Tests simply leave the Clock Tick
Driver out of the Device Driver Table.

  • Property mode set to 100644
File size: 5.7 KB
Line 
1
2/*  ckinit.c
3 *
4 *  This file contains the clock driver initialization for the IDT 4650.
5 *
6 *  Author:     Craig Lebakken <craigl@transition.com>
7 *
8 *  COPYRIGHT (c) 1996 by Transition Networks Inc.
9 *
10 *  To anyone who acknowledges that this file is provided "AS IS"
11 *  without any express or implied warranty:
12 *      permission to use, copy, modify, and distribute this file
13 *      for any purpose is hereby granted without fee, provided that
14 *      the above copyright notice and this notice appears in all
15 *      copies, and that the name of Transition Networks not be used in
16 *      advertising or publicity pertaining to distribution of the
17 *      software without specific, written prior permission.
18 *      Transition Networks makes no representations about the suitability
19 *      of this software for any purpose.
20 *
21 *  Derived from c/src/lib/libbsp/no_cpu/no_bsp/clock/ckinit.c:
22 *
23 *  COPYRIGHT (c) 1989-1999.
24 *  On-Line Applications Research Corporation (OAR).
25 *
26 *  The license and distribution terms for this file may be
27 *  found in the file LICENSE in this distribution or at
28 *  http://www.OARcorp.com/rtems/license.html.
29 *
30 *  $Id$
31 */
32
33/*
34 *  Rather than deleting this, it is commented out to (hopefully) help
35 *  the submitter send updates.
36 *
37 *  static char _sccsid[] = "@(#)ckinit.c 08/20/96     1.3\n";
38 */
39
40
41#include <stdlib.h>
42
43#include <rtems.h>
44#include <rtems/libio.h>
45
46#define EXT_INT5    0x8000  /* external interrupt 5 */
47
48#include "clock.h"
49
50/* formerly in the BSP */
51#if 0
52#define CLOCKS_PER_MICROSECOND ( CPU_CLOCK_RATE_MHZ ) /* equivalent to CPU clock speed in MHz */
53#endif
54
55#define CLOCKS_PER_MICROSECOND \
56  rtems_cpu_configuration_get_clicks_per_microsecond()
57/* to avoid including the bsp */
58mips_isr_entry set_vector( rtems_isr_entry, rtems_vector_number, int );
59
60void Clock_exit( void );
61rtems_isr Clock_isr( rtems_vector_number vector );
62
63
64/*
65 *  The interrupt vector number associated with the clock tick device
66 *  driver.
67 */
68
69#define CLOCK_VECTOR_MASK    EXT_INT5
70#define CLOCK_VECTOR         0x7
71
72/*
73 *  Clock_driver_ticks is a monotonically increasing counter of the
74 *  number of clock ticks since the driver was initialized.
75 */
76
77volatile rtems_unsigned32 Clock_driver_ticks;
78
79/*
80 *  Clock_isrs is the number of clock ISRs until the next invocation of
81 *  the RTEMS clock tick routine.  The clock tick device driver
82 *  gets an interrupt once a millisecond and counts down until the
83 *  length of time between the user configured microseconds per tick
84 *  has passed.
85 */
86
87rtems_unsigned32 Clock_isrs;              /* ISRs until next tick */
88
89/*
90 * These are set by clock driver during its init
91 */
92 
93rtems_device_major_number rtems_clock_major = ~0;
94rtems_device_minor_number rtems_clock_minor;
95
96/*
97 *  The previous ISR on this clock tick interrupt vector.
98 */
99
100rtems_isr_entry  Old_ticker;
101
102void Clock_exit( void );
103
104static unsigned32 mips_timer_rate = 0;
105
106/*
107 *  Isr Handler
108 */
109
110rtems_isr Clock_isr(
111  rtems_vector_number vector
112)
113{
114/*
115 * bump the number of clock driver ticks since initialization
116 *
117 * determine if it is time to announce the passing of tick as configured
118 * to RTEMS through the rtems_clock_tick directive
119 *
120 * perform any timer dependent tasks
121 */
122
123  /* refresh the internal CPU timer */
124  mips_set_timer( mips_timer_rate );
125
126  Clock_driver_ticks += 1;
127
128  rtems_clock_tick();
129}
130
131/* User callback shell (set from Clock_Control) */
132static void (*user_callback)(void);
133
134rtems_isr User_Clock_isr(
135  rtems_vector_number vector
136)
137{
138   /* refresh the internal CPU timer */
139   mips_set_timer( mips_timer_rate );
140
141   if (user_callback)
142      user_callback();
143}
144
145/*
146 *  Install_clock
147 *
148 *  Install a clock tick handleR and reprograms the chip.  This
149 *  is used to initially establish the clock tick.
150 */
151
152void Install_clock(
153  rtems_isr_entry clock_isr
154)
155{
156  /*
157   *  Initialize the clock tick device driver variables
158   */
159
160  Clock_driver_ticks = 0;
161  Clock_isrs = rtems_configuration_get_milliseconds_per_tick();
162
163  Old_ticker = (rtems_isr_entry) set_vector( clock_isr, CLOCK_VECTOR, 1 );
164  /*
165   *  Hardware specific initialize goes here
166   */
167
168  mips_timer_rate =
169     rtems_configuration_get_microseconds_per_tick() * CLOCKS_PER_MICROSECOND;
170  mips_set_timer( mips_timer_rate );
171  enable_int(CLOCK_VECTOR_MASK);
172
173  /*
174   *  Schedule the clock cleanup routine to execute if the application exits.
175   */
176
177  atexit( Clock_exit );
178}
179
180/*
181 *  Clean up before the application exits
182 */
183
184void Clock_exit( void )
185{
186  /* mips: turn off the timer interrupts */
187  disable_int(~CLOCK_VECTOR_MASK);
188}
189
190/*
191 *  Clock_initialize
192 *
193 *  Device driver entry point for clock tick driver initialization.
194 */
195
196rtems_device_driver Clock_initialize(
197  rtems_device_major_number major,
198  rtems_device_minor_number minor,
199  void *pargp
200)
201{
202  Install_clock( Clock_isr );
203 
204  /*
205   * make major/minor avail to others such as shared memory driver
206   */
207 
208  rtems_clock_major = major;
209  rtems_clock_minor = minor;
210 
211  return RTEMS_SUCCESSFUL;
212}
213
214rtems_device_driver Clock_control(
215  rtems_device_major_number major,
216  rtems_device_minor_number minor,
217  void *pargp
218)
219{
220    rtems_unsigned32 isrlevel;
221    rtems_libio_ioctl_args_t *args = pargp;
222 
223    if (args == 0)
224        goto done;
225 
226    /*
227     * This is hokey, but until we get a defined interface
228     * to do this, it will just be this simple...
229     */
230 
231    if (args->command == rtems_build_name('I', 'S', 'R', ' '))
232    {
233        Clock_isr(CLOCK_VECTOR);
234    }
235    else if (args->command == rtems_build_name('N', 'E', 'W', ' '))
236    {
237      rtems_interrupt_disable( isrlevel );
238      user_callback = (void (*)(void))args->buffer;
239      (void) set_vector( User_Clock_isr, CLOCK_VECTOR, 1 );
240      rtems_interrupt_enable( isrlevel );
241    }
242 
243done:
244    return RTEMS_SUCCESSFUL;
245}
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