1 /*
2  * SPDX-FileCopyrightText: 2015-2024 Espressif Systems (Shanghai) CO LTD
3  *
4  * SPDX-License-Identifier: Apache-2.0
5  */
6 
7 #include <stdint.h>
8 #include <stdio.h>
9 #include <stdlib.h>
10 #include <stdbool.h>
11 #include "esp_private/system_internal.h"
12 #include "esp_private/rtc_ctrl.h"
13 #include "esp_private/spi_flash_os.h"
14 #include "esp_log.h"
15 #include "esp_cpu.h"
16 #include "soc/soc.h"
17 #include "soc/rtc_periph.h"
18 #include "esp_attr.h"
19 #include "esp_rom_sys.h"
20 #include "bootloader_flash.h"
21 #include "esp_intr_alloc.h"
22 #include "hal/brownout_hal.h"
23 #include "hal/brownout_ll.h"
24 #include "sdkconfig.h"
25 
26 #if defined(CONFIG_ESP_BROWNOUT_DET_LVL)
27 #define BROWNOUT_DET_LVL CONFIG_ESP_BROWNOUT_DET_LVL
28 #else
29 #define BROWNOUT_DET_LVL 0
30 #endif
31 
32 static __attribute__((unused)) DRAM_ATTR const char TAG[] = "BOD";
33 
34 #if CONFIG_ESP_SYSTEM_BROWNOUT_INTR
rtc_brownout_isr_handler(void * arg)35 IRAM_ATTR static void rtc_brownout_isr_handler(void *arg)
36 {
37     /* Normally RTC ISR clears the interrupt flag after the application-supplied
38      * handler returns. Since restart is called here, the flag needs to be
39      * cleared manually.
40      */
41     brownout_ll_intr_clear();
42 
43     // Stop the other core.
44 #if !CONFIG_ESP_SYSTEM_SINGLE_CORE_MODE
45     const uint32_t core_id = esp_cpu_get_core_id();
46     const uint32_t other_core_id = (core_id == 0) ? 1 : 0;
47     esp_cpu_stall(other_core_id);
48 #endif
49 
50     esp_reset_reason_set_hint(ESP_RST_BROWNOUT);
51 #if CONFIG_SPI_FLASH_BROWNOUT_RESET
52     if (spi_flash_brownout_need_reset()) {
53         bootloader_flash_reset_chip();
54     } else
55 #endif // CONFIG_SPI_FLASH_BROWNOUT_RESET
56     {
57         ESP_DRAM_LOGI(TAG, "Brownout detector was triggered\r\n\r\n");
58     }
59 
60     esp_rom_software_reset_system();
61     while (true) {
62         ;
63     }
64 }
65 #endif // CONFIG_ESP_SYSTEM_BROWNOUT_INTR
66 
esp_brownout_init(void)67 void esp_brownout_init(void)
68 {
69 #if CONFIG_ESP_SYSTEM_BROWNOUT_INTR
70     brownout_hal_config_t cfg = {
71         .threshold = BROWNOUT_DET_LVL,
72         .enabled = true,
73         .reset_enabled = false,
74         .flash_power_down = true,
75         .rf_power_down = true,
76     };
77 
78     brownout_hal_config(&cfg);
79     brownout_ll_intr_clear();
80 #if CONFIG_IDF_TARGET_ESP32C6 || CONFIG_IDF_TARGET_ESP32H2
81     // TODO IDF-6606: LP_RTC_TIMER interrupt source is shared by lp_timer and brownout detector, but lp_timer interrupt
82     // is not used now. An interrupt allocator is needed when lp_timer intr gets supported.
83     esp_intr_alloc(ETS_LP_RTC_TIMER_INTR_SOURCE, ESP_INTR_FLAG_IRAM, &rtc_brownout_isr_handler, NULL, NULL);
84 #else
85     rtc_isr_register(rtc_brownout_isr_handler, NULL, RTC_CNTL_BROWN_OUT_INT_ENA_M, RTC_INTR_FLAG_IRAM);
86 #endif
87     brownout_ll_intr_enable(true);
88 
89 #else // brownout without interrupt
90 
91     brownout_hal_config_t cfg = {
92         .threshold = BROWNOUT_DET_LVL,
93         .enabled = true,
94         .reset_enabled = true,
95         .flash_power_down = true,
96         .rf_power_down = true,
97     };
98 
99     brownout_hal_config(&cfg);
100 #endif
101 }
102 
esp_brownout_disable(void)103 void esp_brownout_disable(void)
104 {
105     brownout_hal_config_t cfg = {
106         .enabled = false,
107     };
108 
109     brownout_hal_config(&cfg);
110 #if CONFIG_ESP_SYSTEM_BROWNOUT_INTR
111     brownout_ll_intr_enable(false);
112     rtc_isr_deregister(rtc_brownout_isr_handler, NULL);
113 #endif // CONFIG_ESP_SYSTEM_BROWNOUT_INTR
114 }
115