Statistics
| Branch: | Revision:

root / hw / heathrow_pic.c @ c68ea704

History | View | Annotate | Download (4.2 kB)

1
/*
2
 * Heathrow PIC support (standard PowerMac PIC)
3
 * 
4
 * Copyright (c) 2005 Fabrice Bellard
5
 * 
6
 * Permission is hereby granted, free of charge, to any person obtaining a copy
7
 * of this software and associated documentation files (the "Software"), to deal
8
 * in the Software without restriction, including without limitation the rights
9
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10
 * copies of the Software, and to permit persons to whom the Software is
11
 * furnished to do so, subject to the following conditions:
12
 *
13
 * The above copyright notice and this permission notice shall be included in
14
 * all copies or substantial portions of the Software.
15
 *
16
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22
 * THE SOFTWARE.
23
 */
24
#include "vl.h"
25

    
26
//#define DEBUG
27

    
28
typedef struct HeathrowPIC {
29
    uint32_t events;
30
    uint32_t mask;
31
    uint32_t levels;
32
    uint32_t level_triggered;
33
} HeathrowPIC;
34

    
35
struct HeathrowPICS {
36
    HeathrowPIC pics[2];
37
};
38

    
39
static inline int check_irq(HeathrowPIC *pic)
40
{
41
    return (pic->events | (pic->levels & pic->level_triggered)) & pic->mask;
42
}
43

    
44
/* update the CPU irq state */
45
static void heathrow_pic_update(HeathrowPICS *s)
46
{
47
    if (check_irq(&s->pics[0]) || check_irq(&s->pics[1])) {
48
        cpu_interrupt(first_cpu, CPU_INTERRUPT_HARD);
49
    } else {
50
        cpu_reset_interrupt(first_cpu, CPU_INTERRUPT_HARD);
51
    }
52
}
53

    
54
static void pic_writel (void *opaque, target_phys_addr_t addr, uint32_t value)
55
{
56
    HeathrowPICS *s = opaque;
57
    HeathrowPIC *pic;
58
    unsigned int n;
59

    
60
    value = bswap32(value);
61
#ifdef DEBUG
62
    printf("pic_writel: %08x: %08x\n",
63
           addr, value);
64
#endif
65
    n = ((addr & 0xfff) - 0x10) >> 4;
66
    if (n >= 2)
67
        return;
68
    pic = &s->pics[n];
69
    switch(addr & 0xf) {
70
    case 0x04:
71
        pic->mask = value;
72
        heathrow_pic_update(s);
73
        break;
74
    case 0x08:
75
        /* do not reset level triggered IRQs */
76
        value &= ~pic->level_triggered;
77
        pic->events &= ~value;
78
        heathrow_pic_update(s);
79
        break;
80
    default:
81
        break;
82
    }
83
}
84

    
85
static uint32_t pic_readl (void *opaque, target_phys_addr_t addr)
86
{
87
    HeathrowPICS *s = opaque;
88
    HeathrowPIC *pic;
89
    unsigned int n;
90
    uint32_t value;
91
    
92
    n = ((addr & 0xfff) - 0x10) >> 4;
93
    if (n >= 2) {
94
        value = 0;
95
    } else {
96
        pic = &s->pics[n];
97
        switch(addr & 0xf) {
98
        case 0x0:
99
            value = pic->events;
100
            break;
101
        case 0x4:
102
            value = pic->mask;
103
            break;
104
        case 0xc:
105
            value = pic->levels;
106
            break;
107
        default:
108
            value = 0;
109
            break;
110
        }
111
    }
112
#ifdef DEBUG
113
    printf("pic_readl: %08x: %08x\n",
114
           addr, value);
115
#endif
116
    value = bswap32(value);
117
    return value;
118
}
119

    
120
static CPUWriteMemoryFunc *pic_write[] = {
121
    &pic_writel,
122
    &pic_writel,
123
    &pic_writel,
124
};
125

    
126
static CPUReadMemoryFunc *pic_read[] = {
127
    &pic_readl,
128
    &pic_readl,
129
    &pic_readl,
130
};
131

    
132

    
133
void heathrow_pic_set_irq(void *opaque, int num, int level)
134
{
135
    HeathrowPICS *s = opaque;
136
    HeathrowPIC *pic;
137
    unsigned int irq_bit;
138

    
139
#if defined(DEBUG)
140
    {
141
        static int last_level[64];
142
        if (last_level[num] != level) {
143
            printf("set_irq: num=0x%02x level=%d\n", num, level);
144
            last_level[num] = level;
145
        }
146
    }
147
#endif
148
    pic = &s->pics[1 - (num >> 5)];
149
    irq_bit = 1 << (num & 0x1f);
150
    if (level) {
151
        pic->events |= irq_bit & ~pic->level_triggered;
152
        pic->levels |= irq_bit;
153
    } else {
154
        pic->levels &= ~irq_bit;
155
    }
156
    heathrow_pic_update(s);
157
}
158

    
159
HeathrowPICS *heathrow_pic_init(int *pmem_index)
160
{
161
    HeathrowPICS *s;
162
    
163
    s = qemu_mallocz(sizeof(HeathrowPICS));
164
    s->pics[0].level_triggered = 0;
165
    s->pics[1].level_triggered = 0x1ff00000;
166
    *pmem_index = cpu_register_io_memory(0, pic_read, pic_write, s);
167
    return s;
168
}