xref: /openbmc/qemu/hw/intc/heathrow_pic.c (revision fe7f9b8e)
1 /*
2  * Heathrow PIC support (OldWorld PowerMac)
3  *
4  * Copyright (c) 2005-2007 Fabrice Bellard
5  * Copyright (c) 2007 Jocelyn Mayer
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 #include "qemu/osdep.h"
26 #include "hw/hw.h"
27 #include "hw/ppc/mac.h"
28 #include "hw/intc/heathrow_pic.h"
29 #include "trace.h"
30 
31 static inline int heathrow_check_irq(HeathrowPICState *pic)
32 {
33     return (pic->events | (pic->levels & pic->level_triggered)) & pic->mask;
34 }
35 
36 /* update the CPU irq state */
37 static void heathrow_update_irq(HeathrowState *s)
38 {
39     if (heathrow_check_irq(&s->pics[0]) ||
40             heathrow_check_irq(&s->pics[1])) {
41         qemu_irq_raise(s->irqs[0]);
42     } else {
43         qemu_irq_lower(s->irqs[0]);
44     }
45 }
46 
47 static void heathrow_write(void *opaque, hwaddr addr,
48                            uint64_t value, unsigned size)
49 {
50     HeathrowState *s = opaque;
51     HeathrowPICState *pic;
52     unsigned int n;
53 
54     n = ((addr & 0xfff) - 0x10) >> 4;
55     trace_heathrow_write(addr, n, value);
56     if (n >= 2)
57         return;
58     pic = &s->pics[n];
59     switch(addr & 0xf) {
60     case 0x04:
61         pic->mask = value;
62         heathrow_update_irq(s);
63         break;
64     case 0x08:
65         /* do not reset level triggered IRQs */
66         value &= ~pic->level_triggered;
67         pic->events &= ~value;
68         heathrow_update_irq(s);
69         break;
70     default:
71         break;
72     }
73 }
74 
75 static uint64_t heathrow_read(void *opaque, hwaddr addr,
76                               unsigned size)
77 {
78     HeathrowState *s = opaque;
79     HeathrowPICState *pic;
80     unsigned int n;
81     uint32_t value;
82 
83     n = ((addr & 0xfff) - 0x10) >> 4;
84     if (n >= 2) {
85         value = 0;
86     } else {
87         pic = &s->pics[n];
88         switch(addr & 0xf) {
89         case 0x0:
90             value = pic->events;
91             break;
92         case 0x4:
93             value = pic->mask;
94             break;
95         case 0xc:
96             value = pic->levels;
97             break;
98         default:
99             value = 0;
100             break;
101         }
102     }
103     trace_heathrow_read(addr, n, value);
104     return value;
105 }
106 
107 static const MemoryRegionOps heathrow_ops = {
108     .read = heathrow_read,
109     .write = heathrow_write,
110     .endianness = DEVICE_LITTLE_ENDIAN,
111 };
112 
113 static void heathrow_set_irq(void *opaque, int num, int level)
114 {
115     HeathrowState *s = opaque;
116     HeathrowPICState *pic;
117     unsigned int irq_bit;
118     int last_level;
119 
120     pic = &s->pics[1 - (num >> 5)];
121     irq_bit = 1 << (num & 0x1f);
122     last_level = (pic->levels & irq_bit) ? 1 : 0;
123 
124     if (level) {
125         pic->events |= irq_bit & ~pic->level_triggered;
126         pic->levels |= irq_bit;
127     } else {
128         pic->levels &= ~irq_bit;
129     }
130 
131     if (last_level != level) {
132         trace_heathrow_set_irq(num, level);
133     }
134 
135     heathrow_update_irq(s);
136 }
137 
138 static const VMStateDescription vmstate_heathrow_pic_one = {
139     .name = "heathrow_pic_one",
140     .version_id = 0,
141     .minimum_version_id = 0,
142     .fields = (VMStateField[]) {
143         VMSTATE_UINT32(events, HeathrowPICState),
144         VMSTATE_UINT32(mask, HeathrowPICState),
145         VMSTATE_UINT32(levels, HeathrowPICState),
146         VMSTATE_UINT32(level_triggered, HeathrowPICState),
147         VMSTATE_END_OF_LIST()
148     }
149 };
150 
151 static const VMStateDescription vmstate_heathrow = {
152     .name = "heathrow_pic",
153     .version_id = 1,
154     .minimum_version_id = 1,
155     .fields = (VMStateField[]) {
156         VMSTATE_STRUCT_ARRAY(pics, HeathrowState, 2, 1,
157                              vmstate_heathrow_pic_one, HeathrowPICState),
158         VMSTATE_END_OF_LIST()
159     }
160 };
161 
162 static void heathrow_reset(DeviceState *d)
163 {
164     HeathrowState *s = HEATHROW(d);
165 
166     s->pics[0].level_triggered = 0;
167     s->pics[1].level_triggered = 0x1ff00000;
168 }
169 
170 static void heathrow_init(Object *obj)
171 {
172     HeathrowState *s = HEATHROW(obj);
173     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
174 
175     /* only 1 CPU */
176     qdev_init_gpio_out(DEVICE(obj), s->irqs, 1);
177 
178     qdev_init_gpio_in(DEVICE(obj), heathrow_set_irq, HEATHROW_NUM_IRQS);
179 
180     memory_region_init_io(&s->mem, OBJECT(s), &heathrow_ops, s,
181                           "heathrow-pic", 0x1000);
182     sysbus_init_mmio(sbd, &s->mem);
183 }
184 
185 static void heathrow_class_init(ObjectClass *oc, void *data)
186 {
187     DeviceClass *dc = DEVICE_CLASS(oc);
188 
189     dc->reset = heathrow_reset;
190     dc->vmsd = &vmstate_heathrow;
191     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
192 }
193 
194 static const TypeInfo heathrow_type_info = {
195     .name = TYPE_HEATHROW,
196     .parent = TYPE_SYS_BUS_DEVICE,
197     .instance_size = sizeof(HeathrowState),
198     .instance_init = heathrow_init,
199     .class_init = heathrow_class_init,
200 };
201 
202 static void heathrow_register_types(void)
203 {
204     type_register_static(&heathrow_type_info);
205 }
206 
207 type_init(heathrow_register_types)
208