Subversion Repositories HelenOS-historic

Rev

Rev 501 | Rev 532 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
1 jermar 1
/*
2
 * Copyright (C) 2001-2004 Jakub Jermar
3
 * All rights reserved.
4
 *
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
7
 * are met:
8
 *
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
28
 
29
#include <arch/types.h>
30
#include <time/clock.h>
31
#include <time/delay.h>
32
#include <arch/interrupt.h>
33
#include <arch/i8259.h>
34
#include <arch/i8254.h>
35
#include <cpu.h>
36
#include <config.h>
37
#include <arch/pm.h>
38
#include <arch/asm.h>
195 vana 39
#include <arch/cpuid.h>
1 jermar 40
#include <arch.h>
195 vana 41
#include <time/delay.h>
1 jermar 42
 
43
/*
44
 * i8254 chip driver.
45
 * Low level time functions.
46
 */
47
 
48
#define CLK_PORT1   0x40
49
#define CLK_PORT4   0x43
50
 
51
 
52
#define CLK_CONST   1193180
53
#define MAGIC_NUMBER    1194
54
 
55
void i8254_init(void)
56
{
57
    i8254_normal_operation();
58
}
59
 
60
void i8254_normal_operation(void)
61
{
62
    outb(CLK_PORT4, 0x36);
514 jermar 63
    pic_disable_irqs(1<<IRQ_CLK);
1 jermar 64
    outb(CLK_PORT1, (CLK_CONST/HZ) & 0xf);
65
    outb(CLK_PORT1, (CLK_CONST/HZ) >> 8);
514 jermar 66
    pic_enable_irqs(1<<IRQ_CLK);
1 jermar 67
    trap_register(VECTOR_CLK, i8254_interrupt);
68
}
69
 
70
#define LOOPS 150000
71
#define SHIFT 11
72
void i8254_calibrate_delay_loop(void)
73
{
74
    __u64 clk1, clk2;
75
    __u32 t1, t2, o1, o2;
76
    __u8 not_ok;
77
 
78
 
79
    /*
80
     * One-shot timer. Count-down from 0xffff at 1193180Hz
81
     * MAGIC_NUMBER is the magic value for 1ms.
82
     */
83
    outb(CLK_PORT4, 0x30);
84
    outb(CLK_PORT1, 0xff);
85
    outb(CLK_PORT1, 0xff);
86
 
87
    do {
125 jermar 88
        /* will read both status and count */
1 jermar 89
        outb(CLK_PORT4, 0xc2);
90
        not_ok = (inb(CLK_PORT1)>>6)&1;
91
        t1 = inb(CLK_PORT1);
92
        t1 |= inb(CLK_PORT1) << 8;
93
    } while (not_ok);
94
 
95
    asm_delay_loop(LOOPS);
96
 
97
    outb(CLK_PORT4, 0xd2);
98
    t2 = inb(CLK_PORT1);
99
    t2 |= inb(CLK_PORT1) << 8;
100
 
101
    /*
102
     * We want to determine the overhead of the calibrating mechanism.
103
     */
104
    outb(CLK_PORT4, 0xd2);
105
    o1 = inb(CLK_PORT1);
106
    o1 |= inb(CLK_PORT1) << 8;
107
 
108
    asm_fake_loop(LOOPS);
109
 
110
    outb(CLK_PORT4, 0xd2);
111
    o2 = inb(CLK_PORT1);
112
    o2 |= inb(CLK_PORT1) << 8;
113
 
125 jermar 114
    CPU->delay_loop_const = ((MAGIC_NUMBER*LOOPS)/1000) / ((t1-t2)-(o1-o2)) + (((MAGIC_NUMBER*LOOPS)/1000) % ((t1-t2)-(o1-o2)) ? 1 : 0);
1 jermar 115
 
116
    clk1 = rdtsc();
117
    delay(1<<SHIFT);
118
    clk2 = rdtsc();
119
 
15 jermar 120
    CPU->frequency_mhz = (clk2-clk1)>>SHIFT;
1 jermar 121
 
122
    return;
123
}
124
 
206 palkovsky 125
void i8254_interrupt(__u8 n, __native stack[])
1 jermar 126
{
127
    trap_virtual_eoi();
128
    clock();
129
}