source: rtems/c/src/lib/libbsp/sh/simsh4/clock/ckinit.c @ a1a84a3

4.104.114.84.95
Last change on this file since a1a84a3 was a1a84a3, checked in by Joel Sherrill <joel.sherrill@…>, on Nov 1, 2002 at 9:57:01 PM

2002-11-01 Joel Sherrill <joel@…>

  • clock/ckinit.c, console/console.c: Removed warnings.
  • Property mode set to 100644
File size: 4.6 KB
Line 
1/*
2 *  Clock Driver for SH4 simulator (timer interrupt not supported now).
3 *
4 *  Copyright (C) 2001 OKTET Ltd., St.-Petersburg, Russia
5 *  Author: Victor V. Vengerov <vvv@oktet.ru>
6 *
7 *  COPYRIGHT (c) 1989-2001.
8 *  On-Line Applications Research Corporation (OAR).
9 *
10 *  The license and distribution terms for this file may be
11 *  found in the file LICENSE in this distribution or at
12 *
13 *  http://www.OARcorp.com/rtems/license.html.
14 *
15 *  $Id$
16 */
17
18#include <stdlib.h>
19#include <bsp.h>
20#include <rtems/libio.h>
21
22/*
23 * Clock_driver_ticks is a monotonically increasing counter of the
24 * number of clock ticks since the driver was initialized.
25 */
26volatile rtems_unsigned32 Clock_driver_ticks;
27
28
29/*
30 * These are set by clock driver during its init
31 */
32 
33rtems_device_major_number rtems_clock_major = ~0;
34rtems_device_minor_number rtems_clock_minor;
35
36rtems_isr (*rtems_clock_hook)(rtems_vector_number) = NULL;
37
38static void
39set_clock_period(rtems_unsigned32 period)
40{
41    asm volatile ("\tmov %0,r0\n"
42                  "\ttrapa\t#4\n" 
43                  : 
44                  : "r" (period)
45                  : "r0" );
46}
47
48/* Clock_isr --
49 *     This handles the timer interrupt by clearing the timer's interrupt
50 *     flag and announcing the clock tick to the system.
51 *
52 * PARAMETERS:
53 *     vector - timer interrupt vector number
54 *
55 * RETURNS:
56 *     none
57 */
58rtems_isr
59Clock_isr (rtems_vector_number vector)
60{
61    /* Announce the clock tick */
62    Clock_driver_ticks++;
63    rtems_clock_tick();
64}
65
66
67/* Clock_exit --
68 *     This shuts down the timer if it was enabled and removes it
69 *     from the interrupt mask.
70 *
71 * PARAMETERS:
72 *     none
73 *
74 * RETURNS:
75 *     none
76 */
77void
78Clock_exit(void)
79{
80    if (BSP_Configuration.ticks_per_timeslice)
81    {
82        /* disable all timer1 interrupts */
83        set_clock_period(0);
84    }
85}
86
87
88/* Install_clock --
89 *     This initialises timer1 with the BSP timeslice config value
90 *     as a reference and sets up the interrupt handler for clock ticks.
91 *
92 * PARAMETERS:
93 *     clock_isr - clock interrupt handler routine
94 *
95 * RETURNS:
96 *     none.
97 */
98static void
99Install_clock(rtems_isr_entry clock_isr)
100{
101    rtems_unsigned32 period;
102    Clock_driver_ticks = 0;
103    if (BSP_Configuration.ticks_per_timeslice)
104    {
105        rtems_isr_entry  old_isr;
106        period = Cpu_table.clicks_per_second / 
107                 BSP_Configuration.ticks_per_timeslice;
108       
109        /* Configure timer interrupts */
110        set_clock_period(period);
111       
112        /* Register the interrupt handler */
113        rtems_interrupt_catch(clock_isr, CLOCK_VECTOR, &old_isr);
114       
115        /* Register the driver exit procedure so we can shutdown */
116        atexit(Clock_exit);
117    }
118}
119
120
121/* Clock_initialize --
122 *     This is called to setup the clock driver. It calls the hardware
123 *     setup function and make the driver major/minor values available
124 *     for other.
125 *
126 * PARAMETERS:
127 *     major - clock device major number
128 *     minor - clock device minor number
129 *     pargp - device driver initialization argument (not used)
130 *
131 * RETURNS:
132 *     RTEMS status code
133 */
134rtems_device_driver
135Clock_initialize(rtems_device_major_number major,
136                 rtems_device_minor_number minor,
137                 void *pargp)
138{
139    Install_clock (Clock_isr);
140 
141    /* Make major/minor avail to others such as shared memory driver */
142    rtems_clock_major = major;
143    rtems_clock_minor = minor;
144 
145    return RTEMS_SUCCESSFUL;
146}
147 
148
149/* Clock_control --
150 *     I/O control (IOCTL) function for Clock driver. At this moment this
151 *     just runs the interrupt handler or re-registers the interrupt handler
152 *     on request.
153 *
154 * PARAMETERS:
155 *     major - clock major device number
156 *     minor - clock minor device number
157 *     pargp - pointer to IOCTL arguments
158 *
159 * RETURNS:
160 *     RTEMS status code
161 */
162rtems_device_driver
163Clock_control(rtems_device_major_number major,
164              rtems_device_minor_number minor,
165              void *pargp)
166{
167    rtems_unsigned32 isrlevel;
168    rtems_libio_ioctl_args_t *args = pargp;
169
170    if (args)
171    {
172        rtems_isr_entry  old_isr;
173        /*
174         * This is hokey, but until we get a defined interface
175         * to do this, it will just be this simple...
176         */
177        if (args->command == rtems_build_name('I', 'S', 'R', ' ')) 
178        {
179            Clock_isr(CLOCK_VECTOR);
180        }
181        else if (args->command == rtems_build_name('N', 'E', 'W', ' '))
182        {
183            rtems_interrupt_disable( isrlevel );
184            rtems_interrupt_catch(Clock_isr, CLOCK_VECTOR, &old_isr);
185            rtems_interrupt_enable( isrlevel );
186        }
187    }
188    return RTEMS_SUCCESSFUL;
189}
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