OVMS3-idf/components/esp32/reset_reason.c
2018-08-20 16:49:20 +08:00

117 lines
3.8 KiB
C

// Copyright 2018 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "esp_system.h"
#include "esp_system_internal.h"
#include "rom/rtc.h"
#include "soc/rtc_cntl_reg.h"
static esp_reset_reason_t s_reset_reason;
static esp_reset_reason_t get_reset_reason(RESET_REASON rtc_reset_reason, esp_reset_reason_t reset_reason_hint)
{
switch (rtc_reset_reason) {
case POWERON_RESET:
return ESP_RST_POWERON;
/* For ESP32, ESP_RST_EXT is never returned */
case SW_CPU_RESET:
case SW_RESET:
case EXT_CPU_RESET: /* unused */
if (reset_reason_hint == ESP_RST_PANIC ||
reset_reason_hint == ESP_RST_BROWNOUT ||
reset_reason_hint == ESP_RST_TASK_WDT ||
reset_reason_hint == ESP_RST_INT_WDT) {
return reset_reason_hint;
}
return ESP_RST_SW;
case DEEPSLEEP_RESET:
return ESP_RST_DEEPSLEEP;
case TG0WDT_SYS_RESET:
return ESP_RST_TASK_WDT;
case TG1WDT_SYS_RESET:
return ESP_RST_INT_WDT;
case OWDT_RESET:
case RTCWDT_SYS_RESET:
case RTCWDT_RTC_RESET:
case RTCWDT_CPU_RESET: /* unused */
case TGWDT_CPU_RESET: /* unused */
return ESP_RST_WDT;
case RTCWDT_BROWN_OUT_RESET: /* unused */
return ESP_RST_BROWNOUT;
case SDIO_RESET:
return ESP_RST_SDIO;
case INTRUSION_RESET: /* unused */
default:
return ESP_RST_UNKNOWN;
}
}
static void __attribute__((constructor)) esp_reset_reason_init(void)
{
s_reset_reason = get_reset_reason(rtc_get_reset_reason(PRO_CPU_NUM),
esp_reset_reason_get_hint());
esp_reset_reason_set_hint(ESP_RST_UNKNOWN);
}
esp_reset_reason_t esp_reset_reason(void)
{
return s_reset_reason;
}
/* Reset reason hint is stored in RTC_RESET_CAUSE_REG, a.k.a. RTC_CNTL_STORE6_REG,
* a.k.a. RTC_ENTRY_ADDR_REG. It is safe to use this register both for the
* deep sleep wake stub entry address and for reset reason hint, since wake stub
* is only used for deep sleep reset, and in this case the reason provided by
* rtc_get_reset_reason is unambiguous.
*
* Same layout is used as for RTC_APB_FREQ_REG (a.k.a. RTC_CNTL_STORE5_REG):
* the value is replicated in low and high half-words. In addition to that,
* MSB is set to 1, which doesn't happen when RTC_CNTL_STORE6_REG contains
* deep sleep wake stub address.
*/
#define RST_REASON_BIT 0x80000000
#define RST_REASON_MASK 0x7FFF
#define RST_REASON_SHIFT 16
/* in IRAM, can be called from panic handler */
void IRAM_ATTR esp_reset_reason_set_hint(esp_reset_reason_t hint)
{
assert((hint & (~RST_REASON_MASK)) == 0);
uint32_t val = hint | (hint << RST_REASON_SHIFT) | RST_REASON_BIT;
REG_WRITE(RTC_RESET_CAUSE_REG, val);
}
/* in IRAM, can be called from panic handler */
esp_reset_reason_t IRAM_ATTR esp_reset_reason_get_hint(void)
{
uint32_t reset_reason_hint = REG_READ(RTC_RESET_CAUSE_REG);
uint32_t high = (reset_reason_hint >> RST_REASON_SHIFT) & RST_REASON_MASK;
uint32_t low = reset_reason_hint & RST_REASON_MASK;
if ((reset_reason_hint & RST_REASON_BIT) == 0 || high != low) {
return ESP_RST_UNKNOWN;
}
return (esp_reset_reason_t) low;
}