1 /*
2 * PowerMac NewWorld MacIO GPIO emulation
3 *
4 * Copyright (c) 2016 Benjamin Herrenschmidt
5 * Copyright (c) 2018 Mark Cave-Ayland
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
26 #include "qemu/osdep.h"
27 #include "hw/qdev-properties.h"
28 #include "migration/vmstate.h"
29 #include "hw/misc/macio/macio.h"
30 #include "hw/misc/macio/gpio.h"
31 #include "hw/irq.h"
32 #include "hw/nmi.h"
33 #include "qemu/log.h"
34 #include "qemu/module.h"
35 #include "trace.h"
36
37 enum MacioGPIORegisterBits {
38 OUT_DATA = 1,
39 IN_DATA = 2,
40 OUT_ENABLE = 4,
41 };
42
macio_set_gpio(MacIOGPIOState * s,uint32_t gpio,bool state)43 void macio_set_gpio(MacIOGPIOState *s, uint32_t gpio, bool state)
44 {
45 uint8_t new_reg;
46
47 trace_macio_set_gpio(gpio, state);
48
49 if (s->gpio_regs[gpio] & OUT_ENABLE) {
50 qemu_log_mask(LOG_GUEST_ERROR,
51 "GPIO: Setting GPIO %d while it's an output\n", gpio);
52 }
53
54 new_reg = s->gpio_regs[gpio] & ~IN_DATA;
55 if (state) {
56 new_reg |= IN_DATA;
57 }
58
59 if (new_reg == s->gpio_regs[gpio]) {
60 return;
61 }
62
63 s->gpio_regs[gpio] = new_reg;
64
65 /*
66 * Note that we probably need to get access to the MPIC config to
67 * decode polarity since qemu always use "raise" regardless.
68 *
69 * For now, we hard wire known GPIOs
70 */
71
72 switch (gpio) {
73 case 1:
74 /* Level low */
75 if (!state) {
76 trace_macio_gpio_irq_assert(gpio);
77 qemu_irq_raise(s->gpio_extirqs[gpio]);
78 } else {
79 trace_macio_gpio_irq_deassert(gpio);
80 qemu_irq_lower(s->gpio_extirqs[gpio]);
81 }
82 break;
83
84 case 9:
85 /* Edge, triggered by NMI below */
86 if (state) {
87 trace_macio_gpio_irq_assert(gpio);
88 qemu_irq_raise(s->gpio_extirqs[gpio]);
89 } else {
90 trace_macio_gpio_irq_deassert(gpio);
91 qemu_irq_lower(s->gpio_extirqs[gpio]);
92 }
93 break;
94
95 default:
96 qemu_log_mask(LOG_UNIMP, "GPIO: setting unimplemented GPIO %d", gpio);
97 }
98 }
99
macio_gpio_write(void * opaque,hwaddr addr,uint64_t value,unsigned size)100 static void macio_gpio_write(void *opaque, hwaddr addr, uint64_t value,
101 unsigned size)
102 {
103 MacIOGPIOState *s = opaque;
104 uint8_t ibit;
105
106 trace_macio_gpio_write(addr, value);
107
108 /* Levels regs are read-only */
109 if (addr < 8) {
110 return;
111 }
112
113 addr -= 8;
114 if (addr < 36) {
115 value &= ~IN_DATA;
116
117 if (value & OUT_ENABLE) {
118 ibit = (value & OUT_DATA) << 1;
119 } else {
120 ibit = s->gpio_regs[addr] & IN_DATA;
121 }
122
123 s->gpio_regs[addr] = value | ibit;
124 }
125 }
126
macio_gpio_read(void * opaque,hwaddr addr,unsigned size)127 static uint64_t macio_gpio_read(void *opaque, hwaddr addr, unsigned size)
128 {
129 MacIOGPIOState *s = opaque;
130 uint64_t val = 0;
131
132 /* Levels regs */
133 if (addr < 8) {
134 val = s->gpio_levels[addr];
135 } else {
136 addr -= 8;
137
138 if (addr < 36) {
139 val = s->gpio_regs[addr];
140 }
141 }
142
143 trace_macio_gpio_read(addr, val);
144 return val;
145 }
146
147 static const MemoryRegionOps macio_gpio_ops = {
148 .read = macio_gpio_read,
149 .write = macio_gpio_write,
150 .endianness = DEVICE_LITTLE_ENDIAN,
151 .impl = {
152 .min_access_size = 1,
153 .max_access_size = 1,
154 },
155 };
156
macio_gpio_init(Object * obj)157 static void macio_gpio_init(Object *obj)
158 {
159 SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
160 MacIOGPIOState *s = MACIO_GPIO(obj);
161 int i;
162
163 for (i = 0; i < 10; i++) {
164 sysbus_init_irq(sbd, &s->gpio_extirqs[i]);
165 }
166
167 memory_region_init_io(&s->gpiomem, OBJECT(s), &macio_gpio_ops, obj,
168 "gpio", 0x30);
169 sysbus_init_mmio(sbd, &s->gpiomem);
170 }
171
172 static const VMStateDescription vmstate_macio_gpio = {
173 .name = "macio_gpio",
174 .version_id = 0,
175 .minimum_version_id = 0,
176 .fields = (const VMStateField[]) {
177 VMSTATE_UINT8_ARRAY(gpio_levels, MacIOGPIOState, 8),
178 VMSTATE_UINT8_ARRAY(gpio_regs, MacIOGPIOState, 36),
179 VMSTATE_END_OF_LIST()
180 }
181 };
182
macio_gpio_reset(DeviceState * dev)183 static void macio_gpio_reset(DeviceState *dev)
184 {
185 MacIOGPIOState *s = MACIO_GPIO(dev);
186
187 /* GPIO 1 is up by default */
188 macio_set_gpio(s, 1, true);
189 }
190
macio_gpio_nmi(NMIState * n,int cpu_index,Error ** errp)191 static void macio_gpio_nmi(NMIState *n, int cpu_index, Error **errp)
192 {
193 macio_set_gpio(MACIO_GPIO(n), 9, true);
194 macio_set_gpio(MACIO_GPIO(n), 9, false);
195 }
196
macio_gpio_class_init(ObjectClass * oc,const void * data)197 static void macio_gpio_class_init(ObjectClass *oc, const void *data)
198 {
199 DeviceClass *dc = DEVICE_CLASS(oc);
200 NMIClass *nc = NMI_CLASS(oc);
201
202 device_class_set_legacy_reset(dc, macio_gpio_reset);
203 dc->vmsd = &vmstate_macio_gpio;
204 nc->nmi_monitor_handler = macio_gpio_nmi;
205 }
206
207 static const TypeInfo macio_gpio_init_info = {
208 .name = TYPE_MACIO_GPIO,
209 .parent = TYPE_SYS_BUS_DEVICE,
210 .instance_size = sizeof(MacIOGPIOState),
211 .instance_init = macio_gpio_init,
212 .class_init = macio_gpio_class_init,
213 .interfaces = (const InterfaceInfo[]) {
214 { TYPE_NMI },
215 { }
216 },
217 };
218
macio_gpio_register_types(void)219 static void macio_gpio_register_types(void)
220 {
221 type_register_static(&macio_gpio_init_info);
222 }
223
224 type_init(macio_gpio_register_types)
225