1 /*
2 * STM32L4x5 EXTI (Extended interrupts and events controller)
3 *
4 * Copyright (c) 2023 Arnaud Minier <arnaud.minier@telecom-paris.fr>
5 * Copyright (c) 2023 Samuel Tardieu <samuel.tardieu@telecom-paris.fr>
6 * Copyright (c) 2023 Inès Varhol <ines.varhol@telecom-paris.fr>
7 *
8 * SPDX-License-Identifier: GPL-2.0-or-later
9 *
10 * This work is licensed under the terms of the GNU GPL, version 2 or later.
11 * See the COPYING file in the top-level directory.
12 *
13 * This work is based on the stm32f4xx_exti by Alistair Francis.
14 * Original code is licensed under the MIT License:
15 *
16 * Copyright (c) 2014 Alistair Francis <alistair@alistair23.me>
17 */
18
19 /*
20 * The reference used is the STMicroElectronics RM0351 Reference manual
21 * for STM32L4x5 and STM32L4x6 advanced Arm ® -based 32-bit MCUs.
22 * https://www.st.com/en/microcontrollers-microprocessors/stm32l4x5/documentation.html
23 */
24
25 #include "qemu/osdep.h"
26 #include "qemu/log.h"
27 #include "trace.h"
28 #include "hw/irq.h"
29 #include "migration/vmstate.h"
30 #include "hw/misc/stm32l4x5_exti.h"
31
32 #define EXTI_IMR1 0x00
33 #define EXTI_EMR1 0x04
34 #define EXTI_RTSR1 0x08
35 #define EXTI_FTSR1 0x0C
36 #define EXTI_SWIER1 0x10
37 #define EXTI_PR1 0x14
38 #define EXTI_IMR2 0x20
39 #define EXTI_EMR2 0x24
40 #define EXTI_RTSR2 0x28
41 #define EXTI_FTSR2 0x2C
42 #define EXTI_SWIER2 0x30
43 #define EXTI_PR2 0x34
44
45 #define EXTI_MAX_IRQ_PER_BANK 32
46 #define EXTI_IRQS_BANK0 32
47 #define EXTI_IRQS_BANK1 8
48
49 static const unsigned irqs_per_bank[EXTI_NUM_REGISTER] = {
50 EXTI_IRQS_BANK0,
51 EXTI_IRQS_BANK1,
52 };
53
54 static const uint32_t exti_romask[EXTI_NUM_REGISTER] = {
55 0xff820000, /* 0b11111111_10000010_00000000_00000000 */
56 0x00000087, /* 0b00000000_00000000_00000000_10000111 */
57 };
58
regbank_index_by_irq(unsigned irq)59 static unsigned regbank_index_by_irq(unsigned irq)
60 {
61 return irq >= EXTI_MAX_IRQ_PER_BANK ? 1 : 0;
62 }
63
regbank_index_by_addr(hwaddr addr)64 static unsigned regbank_index_by_addr(hwaddr addr)
65 {
66 return addr >= EXTI_IMR2 ? 1 : 0;
67 }
68
valid_mask(unsigned bank)69 static unsigned valid_mask(unsigned bank)
70 {
71 return MAKE_64BIT_MASK(0, irqs_per_bank[bank]);
72 }
73
configurable_mask(unsigned bank)74 static unsigned configurable_mask(unsigned bank)
75 {
76 return valid_mask(bank) & ~exti_romask[bank];
77 }
78
stm32l4x5_exti_reset_hold(Object * obj,ResetType type)79 static void stm32l4x5_exti_reset_hold(Object *obj, ResetType type)
80 {
81 Stm32l4x5ExtiState *s = STM32L4X5_EXTI(obj);
82
83 for (unsigned bank = 0; bank < EXTI_NUM_REGISTER; bank++) {
84 s->imr[bank] = exti_romask[bank];
85 s->emr[bank] = 0x00000000;
86 s->rtsr[bank] = 0x00000000;
87 s->ftsr[bank] = 0x00000000;
88 s->swier[bank] = 0x00000000;
89 s->pr[bank] = 0x00000000;
90 s->irq_levels[bank] = 0x00000000;
91 }
92 }
93
stm32l4x5_exti_set_irq(void * opaque,int irq,int level)94 static void stm32l4x5_exti_set_irq(void *opaque, int irq, int level)
95 {
96 Stm32l4x5ExtiState *s = opaque;
97 const unsigned bank = regbank_index_by_irq(irq);
98 const int oirq = irq;
99
100 trace_stm32l4x5_exti_set_irq(irq, level);
101
102 /* Shift the value to enable access in x2 registers. */
103 irq %= EXTI_MAX_IRQ_PER_BANK;
104
105 if (level == extract32(s->irq_levels[bank], irq, 1)) {
106 /* No change in IRQ line state: do nothing */
107 return;
108 }
109 s->irq_levels[bank] = deposit32(s->irq_levels[bank], irq, 1, level);
110
111 /* If the interrupt is masked, pr won't be raised */
112 if (!extract32(s->imr[bank], irq, 1)) {
113 return;
114 }
115
116 /* In case of a direct line interrupt */
117 if (extract32(exti_romask[bank], irq, 1)) {
118 qemu_set_irq(s->irq[oirq], level);
119 return;
120 }
121
122 /* In case of a configurable interrupt */
123 if ((level && extract32(s->rtsr[bank], irq, 1)) ||
124 (!level && extract32(s->ftsr[bank], irq, 1))) {
125
126 s->pr[bank] |= 1 << irq;
127 qemu_irq_pulse(s->irq[oirq]);
128 }
129 }
130
stm32l4x5_exti_read(void * opaque,hwaddr addr,unsigned int size)131 static uint64_t stm32l4x5_exti_read(void *opaque, hwaddr addr,
132 unsigned int size)
133 {
134 Stm32l4x5ExtiState *s = opaque;
135 uint32_t r = 0;
136 const unsigned bank = regbank_index_by_addr(addr);
137
138 switch (addr) {
139 case EXTI_IMR1:
140 case EXTI_IMR2:
141 r = s->imr[bank];
142 break;
143 case EXTI_EMR1:
144 case EXTI_EMR2:
145 r = s->emr[bank];
146 break;
147 case EXTI_RTSR1:
148 case EXTI_RTSR2:
149 r = s->rtsr[bank];
150 break;
151 case EXTI_FTSR1:
152 case EXTI_FTSR2:
153 r = s->ftsr[bank];
154 break;
155 case EXTI_SWIER1:
156 case EXTI_SWIER2:
157 r = s->swier[bank];
158 break;
159 case EXTI_PR1:
160 case EXTI_PR2:
161 r = s->pr[bank];
162 break;
163
164 default:
165 qemu_log_mask(LOG_GUEST_ERROR,
166 "STM32L4X5_exti_read: Bad offset 0x%" HWADDR_PRIx "\n",
167 addr);
168 break;
169 }
170
171 trace_stm32l4x5_exti_read(addr, r);
172
173 return r;
174 }
175
stm32l4x5_exti_write(void * opaque,hwaddr addr,uint64_t val64,unsigned int size)176 static void stm32l4x5_exti_write(void *opaque, hwaddr addr,
177 uint64_t val64, unsigned int size)
178 {
179 Stm32l4x5ExtiState *s = opaque;
180 const unsigned bank = regbank_index_by_addr(addr);
181
182 trace_stm32l4x5_exti_write(addr, val64);
183
184 switch (addr) {
185 case EXTI_IMR1:
186 case EXTI_IMR2:
187 s->imr[bank] = val64 & valid_mask(bank);
188 return;
189 case EXTI_EMR1:
190 case EXTI_EMR2:
191 s->emr[bank] = val64 & valid_mask(bank);
192 return;
193 case EXTI_RTSR1:
194 case EXTI_RTSR2:
195 s->rtsr[bank] = val64 & configurable_mask(bank);
196 return;
197 case EXTI_FTSR1:
198 case EXTI_FTSR2:
199 s->ftsr[bank] = val64 & configurable_mask(bank);
200 return;
201 case EXTI_SWIER1:
202 case EXTI_SWIER2: {
203 const uint32_t set = val64 & configurable_mask(bank);
204 const uint32_t pend = set & ~s->swier[bank] & s->imr[bank] &
205 ~s->pr[bank];
206 s->swier[bank] = set;
207 s->pr[bank] |= pend;
208 for (unsigned i = 0; i < irqs_per_bank[bank]; i++) {
209 if (extract32(pend, i, 1)) {
210 qemu_irq_pulse(s->irq[i + 32 * bank]);
211 }
212 }
213 return;
214 }
215 case EXTI_PR1:
216 case EXTI_PR2: {
217 const uint32_t cleared = s->pr[bank] & val64 & configurable_mask(bank);
218 /* This bit is cleared by writing a 1 to it */
219 s->pr[bank] &= ~cleared;
220 /* Software triggered interrupts are cleared as well */
221 s->swier[bank] &= ~cleared;
222 return;
223 }
224 default:
225 qemu_log_mask(LOG_GUEST_ERROR,
226 "STM32L4X5_exti_write: Bad offset 0x%" HWADDR_PRIx "\n",
227 addr);
228 }
229 }
230
231 static const MemoryRegionOps stm32l4x5_exti_ops = {
232 .read = stm32l4x5_exti_read,
233 .write = stm32l4x5_exti_write,
234 .endianness = DEVICE_NATIVE_ENDIAN,
235 .impl.min_access_size = 4,
236 .impl.max_access_size = 4,
237 .impl.unaligned = false,
238 .valid.min_access_size = 4,
239 .valid.max_access_size = 4,
240 .valid.unaligned = false,
241 };
242
stm32l4x5_exti_init(Object * obj)243 static void stm32l4x5_exti_init(Object *obj)
244 {
245 Stm32l4x5ExtiState *s = STM32L4X5_EXTI(obj);
246
247 for (size_t i = 0; i < EXTI_NUM_LINES; i++) {
248 sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq[i]);
249 }
250
251 memory_region_init_io(&s->mmio, obj, &stm32l4x5_exti_ops, s,
252 TYPE_STM32L4X5_EXTI, 0x400);
253 sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
254
255 qdev_init_gpio_in(DEVICE(obj), stm32l4x5_exti_set_irq, EXTI_NUM_LINES);
256 }
257
258 static const VMStateDescription vmstate_stm32l4x5_exti = {
259 .name = TYPE_STM32L4X5_EXTI,
260 .version_id = 2,
261 .minimum_version_id = 2,
262 .fields = (VMStateField[]) {
263 VMSTATE_UINT32_ARRAY(imr, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
264 VMSTATE_UINT32_ARRAY(emr, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
265 VMSTATE_UINT32_ARRAY(rtsr, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
266 VMSTATE_UINT32_ARRAY(ftsr, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
267 VMSTATE_UINT32_ARRAY(swier, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
268 VMSTATE_UINT32_ARRAY(pr, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
269 VMSTATE_UINT32_ARRAY(irq_levels, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
270 VMSTATE_END_OF_LIST()
271 }
272 };
273
stm32l4x5_exti_class_init(ObjectClass * klass,void * data)274 static void stm32l4x5_exti_class_init(ObjectClass *klass, void *data)
275 {
276 DeviceClass *dc = DEVICE_CLASS(klass);
277 ResettableClass *rc = RESETTABLE_CLASS(klass);
278
279 dc->vmsd = &vmstate_stm32l4x5_exti;
280 rc->phases.hold = stm32l4x5_exti_reset_hold;
281 }
282
283 static const TypeInfo stm32l4x5_exti_types[] = {
284 {
285 .name = TYPE_STM32L4X5_EXTI,
286 .parent = TYPE_SYS_BUS_DEVICE,
287 .instance_size = sizeof(Stm32l4x5ExtiState),
288 .instance_init = stm32l4x5_exti_init,
289 .class_init = stm32l4x5_exti_class_init,
290 }
291 };
292
293 DEFINE_TYPES(stm32l4x5_exti_types)
294