xref: /openbmc/qemu/hw/intc/allwinner-a10-pic.c (revision a6caeee8)
1 /*
2  * Allwinner A10 interrupt controller device emulation
3  *
4  * Copyright (C) 2013 Li Guang
5  * Written by Li Guang <lig.fnst@cn.fujitsu.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License as published by the
9  * Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15  * for more details.
16  */
17 
18 #include "qemu/osdep.h"
19 #include "hw/sysbus.h"
20 #include "migration/vmstate.h"
21 #include "hw/intc/allwinner-a10-pic.h"
22 #include "hw/irq.h"
23 #include "qemu/log.h"
24 #include "qemu/module.h"
25 
26 static void aw_a10_pic_update(AwA10PICState *s)
27 {
28     uint8_t i;
29     int irq = 0, fiq = 0, zeroes;
30 
31     s->vector = 0;
32 
33     for (i = 0; i < AW_A10_PIC_REG_NUM; i++) {
34         irq |= s->irq_pending[i] & ~s->mask[i];
35         fiq |= s->select[i] & s->irq_pending[i] & ~s->mask[i];
36 
37         if (!s->vector) {
38             zeroes = ctz32(s->irq_pending[i] & ~s->mask[i]);
39             if (zeroes != 32) {
40                 s->vector = (i * 32 + zeroes) * 4;
41             }
42         }
43     }
44 
45     qemu_set_irq(s->parent_irq, !!irq);
46     qemu_set_irq(s->parent_fiq, !!fiq);
47 }
48 
49 static void aw_a10_pic_set_irq(void *opaque, int irq, int level)
50 {
51     AwA10PICState *s = opaque;
52 
53     if (level) {
54         set_bit(irq % 32, (void *)&s->irq_pending[irq / 32]);
55     } else {
56         clear_bit(irq % 32, (void *)&s->irq_pending[irq / 32]);
57     }
58     aw_a10_pic_update(s);
59 }
60 
61 static uint64_t aw_a10_pic_read(void *opaque, hwaddr offset, unsigned size)
62 {
63     AwA10PICState *s = opaque;
64     uint8_t index = (offset & 0xc) / 4;
65 
66     switch (offset) {
67     case AW_A10_PIC_VECTOR:
68         return s->vector;
69     case AW_A10_PIC_BASE_ADDR:
70         return s->base_addr;
71     case AW_A10_PIC_PROTECT:
72         return s->protect;
73     case AW_A10_PIC_NMI:
74         return s->nmi;
75     case AW_A10_PIC_IRQ_PENDING ... AW_A10_PIC_IRQ_PENDING + 8:
76         return s->irq_pending[index];
77     case AW_A10_PIC_FIQ_PENDING ... AW_A10_PIC_FIQ_PENDING + 8:
78         return s->fiq_pending[index];
79     case AW_A10_PIC_SELECT ... AW_A10_PIC_SELECT + 8:
80         return s->select[index];
81     case AW_A10_PIC_ENABLE ... AW_A10_PIC_ENABLE + 8:
82         return s->enable[index];
83     case AW_A10_PIC_MASK ... AW_A10_PIC_MASK + 8:
84         return s->mask[index];
85     default:
86         qemu_log_mask(LOG_GUEST_ERROR,
87                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
88         break;
89     }
90 
91     return 0;
92 }
93 
94 static void aw_a10_pic_write(void *opaque, hwaddr offset, uint64_t value,
95                              unsigned size)
96 {
97     AwA10PICState *s = opaque;
98     uint8_t index = (offset & 0xc) / 4;
99 
100     switch (offset) {
101     case AW_A10_PIC_BASE_ADDR:
102         s->base_addr = value & ~0x3;
103         break;
104     case AW_A10_PIC_PROTECT:
105         s->protect = value;
106         break;
107     case AW_A10_PIC_NMI:
108         s->nmi = value;
109         break;
110     case AW_A10_PIC_IRQ_PENDING ... AW_A10_PIC_IRQ_PENDING + 8:
111         /*
112          * The register is read-only; nevertheless, Linux (including
113          * the version originally shipped by Allwinner) pretends to
114          * write to the register. Just ignore it.
115          */
116         break;
117     case AW_A10_PIC_FIQ_PENDING ... AW_A10_PIC_FIQ_PENDING + 8:
118         s->fiq_pending[index] &= ~value;
119         break;
120     case AW_A10_PIC_SELECT ... AW_A10_PIC_SELECT + 8:
121         s->select[index] = value;
122         break;
123     case AW_A10_PIC_ENABLE ... AW_A10_PIC_ENABLE + 8:
124         s->enable[index] = value;
125         break;
126     case AW_A10_PIC_MASK ... AW_A10_PIC_MASK + 8:
127         s->mask[index] = value;
128         break;
129     default:
130         qemu_log_mask(LOG_GUEST_ERROR,
131                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
132         break;
133     }
134 
135     aw_a10_pic_update(s);
136 }
137 
138 static const MemoryRegionOps aw_a10_pic_ops = {
139     .read = aw_a10_pic_read,
140     .write = aw_a10_pic_write,
141     .endianness = DEVICE_NATIVE_ENDIAN,
142 };
143 
144 static const VMStateDescription vmstate_aw_a10_pic = {
145     .name = "a10.pic",
146     .version_id = 1,
147     .minimum_version_id = 1,
148     .fields = (VMStateField[]) {
149         VMSTATE_UINT32(vector, AwA10PICState),
150         VMSTATE_UINT32(base_addr, AwA10PICState),
151         VMSTATE_UINT32(protect, AwA10PICState),
152         VMSTATE_UINT32(nmi, AwA10PICState),
153         VMSTATE_UINT32_ARRAY(irq_pending, AwA10PICState, AW_A10_PIC_REG_NUM),
154         VMSTATE_UINT32_ARRAY(fiq_pending, AwA10PICState, AW_A10_PIC_REG_NUM),
155         VMSTATE_UINT32_ARRAY(enable, AwA10PICState, AW_A10_PIC_REG_NUM),
156         VMSTATE_UINT32_ARRAY(select, AwA10PICState, AW_A10_PIC_REG_NUM),
157         VMSTATE_UINT32_ARRAY(mask, AwA10PICState, AW_A10_PIC_REG_NUM),
158         VMSTATE_END_OF_LIST()
159     }
160 };
161 
162 static void aw_a10_pic_init(Object *obj)
163 {
164     AwA10PICState *s = AW_A10_PIC(obj);
165     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
166 
167      qdev_init_gpio_in(DEVICE(dev), aw_a10_pic_set_irq, AW_A10_PIC_INT_NR);
168      sysbus_init_irq(dev, &s->parent_irq);
169      sysbus_init_irq(dev, &s->parent_fiq);
170      memory_region_init_io(&s->iomem, OBJECT(s), &aw_a10_pic_ops, s,
171                            TYPE_AW_A10_PIC, 0x400);
172      sysbus_init_mmio(dev, &s->iomem);
173 }
174 
175 static void aw_a10_pic_reset(DeviceState *d)
176 {
177     AwA10PICState *s = AW_A10_PIC(d);
178     uint8_t i;
179 
180     s->base_addr = 0;
181     s->protect = 0;
182     s->nmi = 0;
183     s->vector = 0;
184     for (i = 0; i < AW_A10_PIC_REG_NUM; i++) {
185         s->irq_pending[i] = 0;
186         s->fiq_pending[i] = 0;
187         s->select[i] = 0;
188         s->enable[i] = 0;
189         s->mask[i] = 0;
190     }
191 }
192 
193 static void aw_a10_pic_class_init(ObjectClass *klass, void *data)
194 {
195     DeviceClass *dc = DEVICE_CLASS(klass);
196 
197     dc->reset = aw_a10_pic_reset;
198     dc->desc = "allwinner a10 pic";
199     dc->vmsd = &vmstate_aw_a10_pic;
200  }
201 
202 static const TypeInfo aw_a10_pic_info = {
203     .name = TYPE_AW_A10_PIC,
204     .parent = TYPE_SYS_BUS_DEVICE,
205     .instance_size = sizeof(AwA10PICState),
206     .instance_init = aw_a10_pic_init,
207     .class_init = aw_a10_pic_class_init,
208 };
209 
210 static void aw_a10_register_types(void)
211 {
212     type_register_static(&aw_a10_pic_info);
213 }
214 
215 type_init(aw_a10_register_types);
216