xref: /openbmc/qemu/hw/misc/stm32l4x5_syscfg.c (revision 72fa42cf)
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/misc/stm32l4x5_syscfg.h"
30 #include "hw/gpio/stm32l4x5_gpio.h"
31 
32 #define SYSCFG_MEMRMP 0x00
33 #define SYSCFG_CFGR1 0x04
34 #define SYSCFG_EXTICR1 0x08
35 #define SYSCFG_EXTICR2 0x0C
36 #define SYSCFG_EXTICR3 0x10
37 #define SYSCFG_EXTICR4 0x14
38 #define SYSCFG_SCSR 0x18
39 #define SYSCFG_CFGR2 0x1C
40 #define SYSCFG_SWPR 0x20
41 #define SYSCFG_SKR 0x24
42 #define SYSCFG_SWPR2 0x28
43 
44 /* 00000000_00000000_00000001_00000111 */
45 #define ACTIVABLE_BITS_MEMRP 0x00000107
46 
47 /* 11111100_11111111_00000001_00000000 */
48 #define ACTIVABLE_BITS_CFGR1 0xFCFF0100
49 /* 00000000_00000000_00000000_00000001 */
50 #define FIREWALL_DISABLE_CFGR1 0x00000001
51 
52 /* 00000000_00000000_11111111_11111111 */
53 #define ACTIVABLE_BITS_EXTICR 0x0000FFFF
54 
55 /* 00000000_00000000_00000000_00000011 */
56 /* #define ACTIVABLE_BITS_SCSR 0x00000003 */
57 
58 /* 00000000_00000000_00000000_00001111 */
59 #define ECC_LOCK_CFGR2 0x0000000F
60 /* 00000000_00000000_00000001_00000000 */
61 #define SRAM2_PARITY_ERROR_FLAG_CFGR2 0x00000100
62 
63 /* 00000000_00000000_00000000_11111111 */
64 #define ACTIVABLE_BITS_SKR 0x000000FF
65 
66 #define NUM_LINES_PER_EXTICR_REG 4
67 
68 static void stm32l4x5_syscfg_hold_reset(Object *obj, ResetType type)
69 {
70     Stm32l4x5SyscfgState *s = STM32L4X5_SYSCFG(obj);
71 
72     s->memrmp = 0x00000000;
73     s->cfgr1 = 0x7C000001;
74     s->exticr[0] = 0x00000000;
75     s->exticr[1] = 0x00000000;
76     s->exticr[2] = 0x00000000;
77     s->exticr[3] = 0x00000000;
78     s->scsr = 0x00000000;
79     s->cfgr2 = 0x00000000;
80     s->swpr = 0x00000000;
81     s->skr = 0x00000000;
82     s->swpr2 = 0x00000000;
83 }
84 
85 static void stm32l4x5_syscfg_set_irq(void *opaque, int irq, int level)
86 {
87     Stm32l4x5SyscfgState *s = opaque;
88     const uint8_t gpio = irq / GPIO_NUM_PINS;
89     const int line = irq % GPIO_NUM_PINS;
90 
91     const int exticr_reg = line / NUM_LINES_PER_EXTICR_REG;
92     const int startbit = (line % NUM_LINES_PER_EXTICR_REG) * 4;
93 
94     g_assert(gpio < NUM_GPIOS);
95     trace_stm32l4x5_syscfg_set_irq(gpio, line, level);
96 
97     if (extract32(s->exticr[exticr_reg], startbit, 4) == gpio) {
98         trace_stm32l4x5_syscfg_forward_exti(line);
99         qemu_set_irq(s->gpio_out[line], level);
100     }
101 }
102 
103 static uint64_t stm32l4x5_syscfg_read(void *opaque, hwaddr addr,
104                                       unsigned int size)
105 {
106     Stm32l4x5SyscfgState *s = opaque;
107 
108     trace_stm32l4x5_syscfg_read(addr);
109 
110     switch (addr) {
111     case SYSCFG_MEMRMP:
112         return s->memrmp;
113     case SYSCFG_CFGR1:
114         return s->cfgr1;
115     case SYSCFG_EXTICR1...SYSCFG_EXTICR4:
116         return s->exticr[(addr - SYSCFG_EXTICR1) / 4];
117     case SYSCFG_SCSR:
118         return s->scsr;
119     case SYSCFG_CFGR2:
120         return s->cfgr2;
121     case SYSCFG_SWPR:
122         return s->swpr;
123     case SYSCFG_SKR:
124         return s->skr;
125     case SYSCFG_SWPR2:
126         return s->swpr2;
127     default:
128         qemu_log_mask(LOG_GUEST_ERROR,
129                       "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, addr);
130         return 0;
131     }
132 }
133 static void stm32l4x5_syscfg_write(void *opaque, hwaddr addr,
134                                    uint64_t value, unsigned int size)
135 {
136     Stm32l4x5SyscfgState *s = opaque;
137 
138     trace_stm32l4x5_syscfg_write(addr, value);
139 
140     switch (addr) {
141     case SYSCFG_MEMRMP:
142         qemu_log_mask(LOG_UNIMP,
143                       "%s: Changing the memory mapping isn't supported\n",
144                       __func__);
145         s->memrmp = value & ACTIVABLE_BITS_MEMRP;
146         return;
147     case SYSCFG_CFGR1:
148         qemu_log_mask(LOG_UNIMP,
149                       "%s: Functions in CFGRx aren't supported\n",
150                       __func__);
151         /* bit 0 (firewall dis.) is cleared by software, set only by reset. */
152         s->cfgr1 = (s->cfgr1 & value & FIREWALL_DISABLE_CFGR1) |
153                    (value & ACTIVABLE_BITS_CFGR1);
154         return;
155     case SYSCFG_EXTICR1...SYSCFG_EXTICR4:
156         s->exticr[(addr - SYSCFG_EXTICR1) / 4] =
157                 (value & ACTIVABLE_BITS_EXTICR);
158         return;
159     case SYSCFG_SCSR:
160         qemu_log_mask(LOG_UNIMP,
161                       "%s: Erasing SRAM2 isn't supported\n",
162                       __func__);
163         /*
164          * only non reserved bits are :
165          * bit 0 (write-protected by a passkey), bit 1 (meant to be read)
166          * so it serves no purpose yet to add :
167          * s->scsr = value & 0x3;
168          */
169         return;
170     case SYSCFG_CFGR2:
171         qemu_log_mask(LOG_UNIMP,
172                       "%s: Functions in CFGRx aren't supported\n",
173                       __func__);
174         /* bit 8 (SRAM2 PEF) is cleared by software by writing a '1'.*/
175         /* bits[3:0] (ECC Lock) are set by software, cleared only by reset.*/
176         s->cfgr2 = (s->cfgr2 | (value & ECC_LOCK_CFGR2)) &
177                    ~(value & SRAM2_PARITY_ERROR_FLAG_CFGR2);
178         return;
179     case SYSCFG_SWPR:
180         qemu_log_mask(LOG_UNIMP,
181                       "%s: Write protecting SRAM2 isn't supported\n",
182                       __func__);
183         /* These bits are set by software and cleared only by reset.*/
184         s->swpr |= value;
185         return;
186     case SYSCFG_SKR:
187         qemu_log_mask(LOG_UNIMP,
188                       "%s: Erasing SRAM2 isn't supported\n",
189                       __func__);
190         s->skr = value & ACTIVABLE_BITS_SKR;
191         return;
192     case SYSCFG_SWPR2:
193         qemu_log_mask(LOG_UNIMP,
194                       "%s: Write protecting SRAM2 isn't supported\n",
195                       __func__);
196         /* These bits are set by software and cleared only by reset.*/
197         s->swpr2 |= value;
198         return;
199     default:
200         qemu_log_mask(LOG_GUEST_ERROR,
201                       "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, addr);
202     }
203 }
204 
205 static const MemoryRegionOps stm32l4x5_syscfg_ops = {
206     .read = stm32l4x5_syscfg_read,
207     .write = stm32l4x5_syscfg_write,
208     .endianness = DEVICE_NATIVE_ENDIAN,
209     .impl.min_access_size = 4,
210     .impl.max_access_size = 4,
211     .impl.unaligned = false,
212     .valid.min_access_size = 4,
213     .valid.max_access_size = 4,
214     .valid.unaligned = false,
215 };
216 
217 static void stm32l4x5_syscfg_init(Object *obj)
218 {
219     Stm32l4x5SyscfgState *s = STM32L4X5_SYSCFG(obj);
220 
221     memory_region_init_io(&s->mmio, obj, &stm32l4x5_syscfg_ops, s,
222                           TYPE_STM32L4X5_SYSCFG, 0x400);
223     sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
224 
225     qdev_init_gpio_in(DEVICE(obj), stm32l4x5_syscfg_set_irq,
226                       GPIO_NUM_PINS * NUM_GPIOS);
227     qdev_init_gpio_out(DEVICE(obj), s->gpio_out, GPIO_NUM_PINS);
228 }
229 
230 static const VMStateDescription vmstate_stm32l4x5_syscfg = {
231     .name = TYPE_STM32L4X5_SYSCFG,
232     .version_id = 1,
233     .minimum_version_id = 1,
234     .fields = (VMStateField[]) {
235         VMSTATE_UINT32(memrmp, Stm32l4x5SyscfgState),
236         VMSTATE_UINT32(cfgr1, Stm32l4x5SyscfgState),
237         VMSTATE_UINT32_ARRAY(exticr, Stm32l4x5SyscfgState,
238                              SYSCFG_NUM_EXTICR),
239         VMSTATE_UINT32(scsr, Stm32l4x5SyscfgState),
240         VMSTATE_UINT32(cfgr2, Stm32l4x5SyscfgState),
241         VMSTATE_UINT32(swpr, Stm32l4x5SyscfgState),
242         VMSTATE_UINT32(skr, Stm32l4x5SyscfgState),
243         VMSTATE_UINT32(swpr2, Stm32l4x5SyscfgState),
244         VMSTATE_END_OF_LIST()
245     }
246 };
247 
248 static void stm32l4x5_syscfg_class_init(ObjectClass *klass, void *data)
249 {
250     DeviceClass *dc = DEVICE_CLASS(klass);
251     ResettableClass *rc = RESETTABLE_CLASS(klass);
252 
253     dc->vmsd = &vmstate_stm32l4x5_syscfg;
254     rc->phases.hold = stm32l4x5_syscfg_hold_reset;
255 }
256 
257 static const TypeInfo stm32l4x5_syscfg_info[] = {
258     {
259         .name          = TYPE_STM32L4X5_SYSCFG,
260         .parent        = TYPE_SYS_BUS_DEVICE,
261         .instance_size = sizeof(Stm32l4x5SyscfgState),
262         .instance_init = stm32l4x5_syscfg_init,
263         .class_init    = stm32l4x5_syscfg_class_init,
264     }
265 };
266 
267 DEFINE_TYPES(stm32l4x5_syscfg_info)
268