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 18 static uint32_t id2reg_offset(unsigned int reset_id) 19 { 20 return ((reset_id & GENMASK(31, 5)) >> 5) * sizeof(uint32_t); 21 } 22 23 static uint8_t id2reg_bit_pos(unsigned int reset_id) 24 { 25 return (uint8_t)(reset_id & GENMASK(4, 0)); 26 } 27 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 56 int stm32mp_reset_assert(uint32_t id, unsigned int to_us) 57 { 58 return reset_toggle(id, to_us, true); 59 } 60 61 int stm32mp_reset_deassert(uint32_t id, unsigned int to_us) 62 { 63 return reset_toggle(id, to_us, false); 64 } 65 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