xref: /openbmc/qemu/hw/intc/allwinner-a10-pic.c (revision ba632924)
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 "hw/devices.h"
21 #include "sysemu/sysemu.h"
22 #include "hw/intc/allwinner-a10-pic.h"
23 #include "qemu/log.h"
24 
25 static void aw_a10_pic_update(AwA10PICState *s)
26 {
27     uint8_t i;
28     int irq = 0, fiq = 0, zeroes;
29 
30     s->vector = 0;
31 
32     for (i = 0; i < AW_A10_PIC_REG_NUM; i++) {
33         irq |= s->irq_pending[i] & ~s->mask[i];
34         fiq |= s->select[i] & s->irq_pending[i] & ~s->mask[i];
35 
36         if (!s->vector) {
37             zeroes = ctz32(s->irq_pending[i] & ~s->mask[i]);
38             if (zeroes != 32) {
39                 s->vector = (i * 32 + zeroes) * 4;
40             }
41         }
42     }
43 
44     qemu_set_irq(s->parent_irq, !!irq);
45     qemu_set_irq(s->parent_fiq, !!fiq);
46 }
47 
48 static void aw_a10_pic_set_irq(void *opaque, int irq, int level)
49 {
50     AwA10PICState *s = opaque;
51 
52     if (level) {
53         set_bit(irq % 32, (void *)&s->irq_pending[irq / 32]);
54     } else {
55         clear_bit(irq % 32, (void *)&s->irq_pending[irq / 32]);
56     }
57     aw_a10_pic_update(s);
58 }
59 
60 static uint64_t aw_a10_pic_read(void *opaque, hwaddr offset, unsigned size)
61 {
62     AwA10PICState *s = opaque;
63     uint8_t index = (offset & 0xc) / 4;
64 
65     switch (offset) {
66     case AW_A10_PIC_VECTOR:
67         return s->vector;
68     case AW_A10_PIC_BASE_ADDR:
69         return s->base_addr;
70     case AW_A10_PIC_PROTECT:
71         return s->protect;
72     case AW_A10_PIC_NMI:
73         return s->nmi;
74     case AW_A10_PIC_IRQ_PENDING ... AW_A10_PIC_IRQ_PENDING + 8:
75         return s->irq_pending[index];
76     case AW_A10_PIC_FIQ_PENDING ... AW_A10_PIC_FIQ_PENDING + 8:
77         return s->fiq_pending[index];
78     case AW_A10_PIC_SELECT ... AW_A10_PIC_SELECT + 8:
79         return s->select[index];
80     case AW_A10_PIC_ENABLE ... AW_A10_PIC_ENABLE + 8:
81         return s->enable[index];
82     case AW_A10_PIC_MASK ... AW_A10_PIC_MASK + 8:
83         return s->mask[index];
84     default:
85         qemu_log_mask(LOG_GUEST_ERROR,
86                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
87         break;
88     }
89 
90     return 0;
91 }
92 
93 static void aw_a10_pic_write(void *opaque, hwaddr offset, uint64_t value,
94                              unsigned size)
95 {
96     AwA10PICState *s = opaque;
97     uint8_t index = (offset & 0xc) / 4;
98 
99     switch (offset) {
100     case AW_A10_PIC_BASE_ADDR:
101         s->base_addr = value & ~0x3;
102         break;
103     case AW_A10_PIC_PROTECT:
104         s->protect = value;
105         break;
106     case AW_A10_PIC_NMI:
107         s->nmi = value;
108         break;
109     case AW_A10_PIC_IRQ_PENDING ... AW_A10_PIC_IRQ_PENDING + 8:
110         /*
111          * The register is read-only; nevertheless, Linux (including
112          * the version originally shipped by Allwinner) pretends to
113          * write to the register. Just ignore it.
114          */
115         break;
116     case AW_A10_PIC_FIQ_PENDING ... AW_A10_PIC_FIQ_PENDING + 8:
117         s->fiq_pending[index] &= ~value;
118         break;
119     case AW_A10_PIC_SELECT ... AW_A10_PIC_SELECT + 8:
120         s->select[index] = value;
121         break;
122     case AW_A10_PIC_ENABLE ... AW_A10_PIC_ENABLE + 8:
123         s->enable[index] = value;
124         break;
125     case AW_A10_PIC_MASK ... AW_A10_PIC_MASK + 8:
126         s->mask[index] = value;
127         break;
128     default:
129         qemu_log_mask(LOG_GUEST_ERROR,
130                       "%s: Bad offset 0x%x\n",  __func__, (int)offset);
131         break;
132     }
133 
134     aw_a10_pic_update(s);
135 }
136 
137 static const MemoryRegionOps aw_a10_pic_ops = {
138     .read = aw_a10_pic_read,
139     .write = aw_a10_pic_write,
140     .endianness = DEVICE_NATIVE_ENDIAN,
141 };
142 
143 static const VMStateDescription vmstate_aw_a10_pic = {
144     .name = "a10.pic",
145     .version_id = 1,
146     .minimum_version_id = 1,
147     .fields = (VMStateField[]) {
148         VMSTATE_UINT32(vector, AwA10PICState),
149         VMSTATE_UINT32(base_addr, AwA10PICState),
150         VMSTATE_UINT32(protect, AwA10PICState),
151         VMSTATE_UINT32(nmi, AwA10PICState),
152         VMSTATE_UINT32_ARRAY(irq_pending, AwA10PICState, AW_A10_PIC_REG_NUM),
153         VMSTATE_UINT32_ARRAY(fiq_pending, AwA10PICState, AW_A10_PIC_REG_NUM),
154         VMSTATE_UINT32_ARRAY(enable, AwA10PICState, AW_A10_PIC_REG_NUM),
155         VMSTATE_UINT32_ARRAY(select, AwA10PICState, AW_A10_PIC_REG_NUM),
156         VMSTATE_UINT32_ARRAY(mask, AwA10PICState, AW_A10_PIC_REG_NUM),
157         VMSTATE_END_OF_LIST()
158     }
159 };
160 
161 static void aw_a10_pic_init(Object *obj)
162 {
163     AwA10PICState *s = AW_A10_PIC(obj);
164     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
165 
166      qdev_init_gpio_in(DEVICE(dev), aw_a10_pic_set_irq, AW_A10_PIC_INT_NR);
167      sysbus_init_irq(dev, &s->parent_irq);
168      sysbus_init_irq(dev, &s->parent_fiq);
169      memory_region_init_io(&s->iomem, OBJECT(s), &aw_a10_pic_ops, s,
170                            TYPE_AW_A10_PIC, 0x400);
171      sysbus_init_mmio(dev, &s->iomem);
172 }
173 
174 static void aw_a10_pic_reset(DeviceState *d)
175 {
176     AwA10PICState *s = AW_A10_PIC(d);
177     uint8_t i;
178 
179     s->base_addr = 0;
180     s->protect = 0;
181     s->nmi = 0;
182     s->vector = 0;
183     for (i = 0; i < AW_A10_PIC_REG_NUM; i++) {
184         s->irq_pending[i] = 0;
185         s->fiq_pending[i] = 0;
186         s->select[i] = 0;
187         s->enable[i] = 0;
188         s->mask[i] = 0;
189     }
190 }
191 
192 static void aw_a10_pic_class_init(ObjectClass *klass, void *data)
193 {
194     DeviceClass *dc = DEVICE_CLASS(klass);
195 
196     dc->reset = aw_a10_pic_reset;
197     dc->desc = "allwinner a10 pic";
198     dc->vmsd = &vmstate_aw_a10_pic;
199  }
200 
201 static const TypeInfo aw_a10_pic_info = {
202     .name = TYPE_AW_A10_PIC,
203     .parent = TYPE_SYS_BUS_DEVICE,
204     .instance_size = sizeof(AwA10PICState),
205     .instance_init = aw_a10_pic_init,
206     .class_init = aw_a10_pic_class_init,
207 };
208 
209 static void aw_a10_register_types(void)
210 {
211     type_register_static(&aw_a10_pic_info);
212 }
213 
214 type_init(aw_a10_register_types);
215