xref: /openbmc/qemu/hw/misc/stm32l4x5_syscfg.c (revision b278b60d)
1 /*
2  * STM32L4x5 SYSCFG (System Configuration Controller)
3  *
4  * Copyright (c) 2023 Arnaud Minier <arnaud.minier@telecom-paris.fr>
5  * Copyright (c) 2023 Inès Varhol <ines.varhol@telecom-paris.fr>
6  *
7  * SPDX-License-Identifier: GPL-2.0-or-later
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
10  * See the COPYING file in the top-level directory.
11  *
12  * This work is based on the stm32f4xx_syscfg by Alistair Francis.
13  * Original code is licensed under the MIT License:
14  *
15  * Copyright (c) 2014 Alistair Francis <alistair@alistair23.me>
16  */
17 
18 /*
19  * The reference used is the STMicroElectronics RM0351 Reference manual
20  * for STM32L4x5 and STM32L4x6 advanced Arm ® -based 32-bit MCUs.
21  * https://www.st.com/en/microcontrollers-microprocessors/stm32l4x5/documentation.html
22  */
23 
24 #include "qemu/osdep.h"
25 #include "qemu/log.h"
26 #include "trace.h"
27 #include "hw/irq.h"
28 #include "migration/vmstate.h"
29 #include "hw/clock.h"
30 #include "hw/qdev-clock.h"
31 #include "qapi/error.h"
32 #include "hw/misc/stm32l4x5_syscfg.h"
33 #include "hw/gpio/stm32l4x5_gpio.h"
34 
35 #define SYSCFG_MEMRMP 0x00
36 #define SYSCFG_CFGR1 0x04
37 #define SYSCFG_EXTICR1 0x08
38 #define SYSCFG_EXTICR2 0x0C
39 #define SYSCFG_EXTICR3 0x10
40 #define SYSCFG_EXTICR4 0x14
41 #define SYSCFG_SCSR 0x18
42 #define SYSCFG_CFGR2 0x1C
43 #define SYSCFG_SWPR 0x20
44 #define SYSCFG_SKR 0x24
45 #define SYSCFG_SWPR2 0x28
46 
47 /* 00000000_00000000_00000001_00000111 */
48 #define ACTIVABLE_BITS_MEMRP 0x00000107
49 
50 /* 11111100_11111111_00000001_00000000 */
51 #define ACTIVABLE_BITS_CFGR1 0xFCFF0100
52 /* 00000000_00000000_00000000_00000001 */
53 #define FIREWALL_DISABLE_CFGR1 0x00000001
54 
55 /* 00000000_00000000_11111111_11111111 */
56 #define ACTIVABLE_BITS_EXTICR 0x0000FFFF
57 
58 /* 00000000_00000000_00000000_00000011 */
59 /* #define ACTIVABLE_BITS_SCSR 0x00000003 */
60 
61 /* 00000000_00000000_00000000_00001111 */
62 #define ECC_LOCK_CFGR2 0x0000000F
63 /* 00000000_00000000_00000001_00000000 */
64 #define SRAM2_PARITY_ERROR_FLAG_CFGR2 0x00000100
65 
66 /* 00000000_00000000_00000000_11111111 */
67 #define ACTIVABLE_BITS_SKR 0x000000FF
68 
69 #define NUM_LINES_PER_EXTICR_REG 4
70 
71 static void stm32l4x5_syscfg_hold_reset(Object *obj, ResetType type)
72 {
73     Stm32l4x5SyscfgState *s = STM32L4X5_SYSCFG(obj);
74 
75     s->memrmp = 0x00000000;
76     s->cfgr1 = 0x7C000001;
77     s->exticr[0] = 0x00000000;
78     s->exticr[1] = 0x00000000;
79     s->exticr[2] = 0x00000000;
80     s->exticr[3] = 0x00000000;
81     s->scsr = 0x00000000;
82     s->cfgr2 = 0x00000000;
83     s->swpr = 0x00000000;
84     s->skr = 0x00000000;
85     s->swpr2 = 0x00000000;
86 }
87 
88 static void stm32l4x5_syscfg_set_irq(void *opaque, int irq, int level)
89 {
90     Stm32l4x5SyscfgState *s = opaque;
91     const uint8_t gpio = irq / GPIO_NUM_PINS;
92     const int line = irq % GPIO_NUM_PINS;
93 
94     const int exticr_reg = line / NUM_LINES_PER_EXTICR_REG;
95     const int startbit = (line % NUM_LINES_PER_EXTICR_REG) * 4;
96 
97     g_assert(gpio < NUM_GPIOS);
98     trace_stm32l4x5_syscfg_set_irq(gpio, line, level);
99 
100     if (extract32(s->exticr[exticr_reg], startbit, 4) == gpio) {
101         trace_stm32l4x5_syscfg_forward_exti(line);
102         qemu_set_irq(s->gpio_out[line], level);
103     }
104 }
105 
106 static uint64_t stm32l4x5_syscfg_read(void *opaque, hwaddr addr,
107                                       unsigned int size)
108 {
109     Stm32l4x5SyscfgState *s = opaque;
110 
111     trace_stm32l4x5_syscfg_read(addr);
112 
113     switch (addr) {
114     case SYSCFG_MEMRMP:
115         return s->memrmp;
116     case SYSCFG_CFGR1:
117         return s->cfgr1;
118     case SYSCFG_EXTICR1...SYSCFG_EXTICR4:
119         return s->exticr[(addr - SYSCFG_EXTICR1) / 4];
120     case SYSCFG_SCSR:
121         return s->scsr;
122     case SYSCFG_CFGR2:
123         return s->cfgr2;
124     case SYSCFG_SWPR:
125         return s->swpr;
126     case SYSCFG_SKR:
127         return s->skr;
128     case SYSCFG_SWPR2:
129         return s->swpr2;
130     default:
131         qemu_log_mask(LOG_GUEST_ERROR,
132                       "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, addr);
133         return 0;
134     }
135 }
136 static void stm32l4x5_syscfg_write(void *opaque, hwaddr addr,
137                                    uint64_t value, unsigned int size)
138 {
139     Stm32l4x5SyscfgState *s = opaque;
140 
141     trace_stm32l4x5_syscfg_write(addr, value);
142 
143     switch (addr) {
144     case SYSCFG_MEMRMP:
145         qemu_log_mask(LOG_UNIMP,
146                       "%s: Changing the memory mapping isn't supported\n",
147                       __func__);
148         s->memrmp = value & ACTIVABLE_BITS_MEMRP;
149         return;
150     case SYSCFG_CFGR1:
151         qemu_log_mask(LOG_UNIMP,
152                       "%s: Functions in CFGRx aren't supported\n",
153                       __func__);
154         /* bit 0 (firewall dis.) is cleared by software, set only by reset. */
155         s->cfgr1 = (s->cfgr1 & value & FIREWALL_DISABLE_CFGR1) |
156                    (value & ACTIVABLE_BITS_CFGR1);
157         return;
158     case SYSCFG_EXTICR1...SYSCFG_EXTICR4:
159         s->exticr[(addr - SYSCFG_EXTICR1) / 4] =
160                 (value & ACTIVABLE_BITS_EXTICR);
161         return;
162     case SYSCFG_SCSR:
163         qemu_log_mask(LOG_UNIMP,
164                       "%s: Erasing SRAM2 isn't supported\n",
165                       __func__);
166         /*
167          * only non reserved bits are :
168          * bit 0 (write-protected by a passkey), bit 1 (meant to be read)
169          * so it serves no purpose yet to add :
170          * s->scsr = value & 0x3;
171          */
172         return;
173     case SYSCFG_CFGR2:
174         qemu_log_mask(LOG_UNIMP,
175                       "%s: Functions in CFGRx aren't supported\n",
176                       __func__);
177         /* bit 8 (SRAM2 PEF) is cleared by software by writing a '1'.*/
178         /* bits[3:0] (ECC Lock) are set by software, cleared only by reset.*/
179         s->cfgr2 = (s->cfgr2 | (value & ECC_LOCK_CFGR2)) &
180                    ~(value & SRAM2_PARITY_ERROR_FLAG_CFGR2);
181         return;
182     case SYSCFG_SWPR:
183         qemu_log_mask(LOG_UNIMP,
184                       "%s: Write protecting SRAM2 isn't supported\n",
185                       __func__);
186         /* These bits are set by software and cleared only by reset.*/
187         s->swpr |= value;
188         return;
189     case SYSCFG_SKR:
190         qemu_log_mask(LOG_UNIMP,
191                       "%s: Erasing SRAM2 isn't supported\n",
192                       __func__);
193         s->skr = value & ACTIVABLE_BITS_SKR;
194         return;
195     case SYSCFG_SWPR2:
196         qemu_log_mask(LOG_UNIMP,
197                       "%s: Write protecting SRAM2 isn't supported\n",
198                       __func__);
199         /* These bits are set by software and cleared only by reset.*/
200         s->swpr2 |= value;
201         return;
202     default:
203         qemu_log_mask(LOG_GUEST_ERROR,
204                       "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, addr);
205     }
206 }
207 
208 static const MemoryRegionOps stm32l4x5_syscfg_ops = {
209     .read = stm32l4x5_syscfg_read,
210     .write = stm32l4x5_syscfg_write,
211     .endianness = DEVICE_NATIVE_ENDIAN,
212     .impl.min_access_size = 4,
213     .impl.max_access_size = 4,
214     .impl.unaligned = false,
215     .valid.min_access_size = 4,
216     .valid.max_access_size = 4,
217     .valid.unaligned = false,
218 };
219 
220 static void stm32l4x5_syscfg_init(Object *obj)
221 {
222     Stm32l4x5SyscfgState *s = STM32L4X5_SYSCFG(obj);
223 
224     memory_region_init_io(&s->mmio, obj, &stm32l4x5_syscfg_ops, s,
225                           TYPE_STM32L4X5_SYSCFG, 0x400);
226     sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
227 
228     qdev_init_gpio_in(DEVICE(obj), stm32l4x5_syscfg_set_irq,
229                       GPIO_NUM_PINS * NUM_GPIOS);
230     qdev_init_gpio_out(DEVICE(obj), s->gpio_out, GPIO_NUM_PINS);
231     s->clk = qdev_init_clock_in(DEVICE(s), "clk", NULL, s, 0);
232 }
233 
234 static void stm32l4x5_syscfg_realize(DeviceState *dev, Error **errp)
235 {
236     Stm32l4x5SyscfgState *s = STM32L4X5_SYSCFG(dev);
237     if (!clock_has_source(s->clk)) {
238         error_setg(errp, "SYSCFG: clk input must be connected");
239         return;
240     }
241 }
242 
243 static const VMStateDescription vmstate_stm32l4x5_syscfg = {
244     .name = TYPE_STM32L4X5_SYSCFG,
245     .version_id = 2,
246     .minimum_version_id = 2,
247     .fields = (VMStateField[]) {
248         VMSTATE_UINT32(memrmp, Stm32l4x5SyscfgState),
249         VMSTATE_UINT32(cfgr1, Stm32l4x5SyscfgState),
250         VMSTATE_UINT32_ARRAY(exticr, Stm32l4x5SyscfgState,
251                              SYSCFG_NUM_EXTICR),
252         VMSTATE_UINT32(scsr, Stm32l4x5SyscfgState),
253         VMSTATE_UINT32(cfgr2, Stm32l4x5SyscfgState),
254         VMSTATE_UINT32(swpr, Stm32l4x5SyscfgState),
255         VMSTATE_UINT32(skr, Stm32l4x5SyscfgState),
256         VMSTATE_UINT32(swpr2, Stm32l4x5SyscfgState),
257         VMSTATE_CLOCK(clk, Stm32l4x5SyscfgState),
258         VMSTATE_END_OF_LIST()
259     }
260 };
261 
262 static void stm32l4x5_syscfg_class_init(ObjectClass *klass, void *data)
263 {
264     DeviceClass *dc = DEVICE_CLASS(klass);
265     ResettableClass *rc = RESETTABLE_CLASS(klass);
266 
267     dc->vmsd = &vmstate_stm32l4x5_syscfg;
268     dc->realize = stm32l4x5_syscfg_realize;
269     rc->phases.hold = stm32l4x5_syscfg_hold_reset;
270 }
271 
272 static const TypeInfo stm32l4x5_syscfg_info[] = {
273     {
274         .name          = TYPE_STM32L4X5_SYSCFG,
275         .parent        = TYPE_SYS_BUS_DEVICE,
276         .instance_size = sizeof(Stm32l4x5SyscfgState),
277         .instance_init = stm32l4x5_syscfg_init,
278         .class_init    = stm32l4x5_syscfg_class_init,
279     }
280 };
281 
282 DEFINE_TYPES(stm32l4x5_syscfg_info)
283