1 /*
2 * Copyright (c) 2024, STMicroelectronics - All Rights Reserved
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7 #include <errno.h>
8 #include <stdbool.h>
9
10 #include <common/debug.h>
11 #include <drivers/delay_timer.h>
12 #include <drivers/st/stm32mp_reset.h>
13 #include <lib/mmio.h>
14 #include <lib/utils_def.h>
15
16 #include <platform_def.h>
17
id2reg_offset(unsigned int reset_id)18 static uint32_t id2reg_offset(unsigned int reset_id)
19 {
20 return ((reset_id & GENMASK(31, 5)) >> 5) * sizeof(uint32_t);
21 }
22
id2reg_bit_pos(unsigned int reset_id)23 static uint8_t id2reg_bit_pos(unsigned int reset_id)
24 {
25 return (uint8_t)(reset_id & GENMASK(4, 0));
26 }
27
reset_toggle(uint32_t id,unsigned int to_us,bool reset_status)28 static int reset_toggle(uint32_t id, unsigned int to_us, bool reset_status)
29 {
30 uint32_t offset = id2reg_offset(id);
31 uint32_t bitmsk = BIT(id2reg_bit_pos(id));
32 uint32_t bit_check;
33 uintptr_t rcc_base = stm32mp_rcc_base();
34
35 if (reset_status) {
36 mmio_setbits_32(rcc_base + offset, bitmsk);
37 bit_check = bitmsk;
38 } else {
39 mmio_clrbits_32(rcc_base + offset, bitmsk);
40 bit_check = 0U;
41 }
42
43 if (to_us != 0U) {
44 uint64_t timeout_ref = timeout_init_us(to_us);
45
46 while ((mmio_read_32(rcc_base + offset) & bitmsk) != bit_check) {
47 if (timeout_elapsed(timeout_ref)) {
48 return -ETIMEDOUT;
49 }
50 }
51 }
52
53 return 0;
54 }
55
stm32mp_reset_assert(uint32_t id,unsigned int to_us)56 int stm32mp_reset_assert(uint32_t id, unsigned int to_us)
57 {
58 return reset_toggle(id, to_us, true);
59 }
60
stm32mp_reset_deassert(uint32_t id,unsigned int to_us)61 int stm32mp_reset_deassert(uint32_t id, unsigned int to_us)
62 {
63 return reset_toggle(id, to_us, false);
64 }
65
stm32mp_system_reset(void)66 void __dead2 stm32mp_system_reset(void)
67 {
68 uintptr_t rcc_base = stm32mp_rcc_base();
69
70 mmio_setbits_32(rcc_base + RCC_GRSTCSETR, RCC_GRSTCSETR_SYSRST);
71
72 /* Loop in case system reset is not immediately caught */
73 while (true) {
74 wfi();
75 }
76 }
77