/* * This function is not exposed as an API at this point, * because FreeRTOS doesn't yet support dynamic changing of * CPU frequency. Also we need to implement hooks for * components which want to be notified of CPU frequency * changes. */ void esp_clk_init(void) { rtc_config_t cfg = RTC_CONFIG_DEFAULT(); rtc_init(cfg); rtc_clk_fast_freq_set(RTC_FAST_FREQ_8M); #ifdef CONFIG_ESP32_RTC_CLOCK_SOURCE_EXTERNAL_CRYSTAL select_rtc_slow_clk(RTC_SLOW_FREQ_32K_XTAL); #else select_rtc_slow_clk(RTC_SLOW_FREQ_RTC); #endif uint32_t freq_mhz = CONFIG_ESP32_DEFAULT_CPU_FREQ_MHZ; rtc_cpu_freq_t freq = RTC_CPU_FREQ_80M; switch(freq_mhz) { case 240: freq = RTC_CPU_FREQ_240M; break; case 160: freq = RTC_CPU_FREQ_160M; break; default: freq_mhz = 80; /* no break */ case 80: freq = RTC_CPU_FREQ_80M; break; } // Wait for UART TX to finish, otherwise some UART output will be lost // when switching APB frequency uart_tx_wait_idle(CONFIG_CONSOLE_UART_NUM); rtc_clk_cpu_freq_set(freq); }
void IRAM_ATTR pm_off(void) { DEBUG ("%s\n", __func__); /* suspend UARTs */ for (int i = 0; i < 3; ++i) { REG_SET_BIT(UART_FLOW_CONF_REG(i), UART_FORCE_XOFF); uart_tx_wait_idle(i); } /* set all power down flags */ uint32_t pd_flags = RTC_SLEEP_PD_DIG | RTC_SLEEP_PD_RTC_PERIPH | RTC_SLEEP_PD_RTC_SLOW_MEM | RTC_SLEEP_PD_RTC_FAST_MEM | RTC_SLEEP_PD_RTC_MEM_FOLLOW_CPU | RTC_SLEEP_PD_VDDSDIO; rtc_sleep_config_t config = RTC_SLEEP_CONFIG_DEFAULT(pd_flags); config.wifi_pd_en = 1; config.rom_mem_pd_en = 1; config.lslp_meminf_pd = 1; /* Save current frequency and switch to XTAL */ rtc_cpu_freq_t cpu_freq = rtc_clk_cpu_freq_get(); rtc_clk_cpu_freq_set(RTC_CPU_FREQ_XTAL); /* set deep sleep duration to forever */ rtc_sleep_set_wakeup_time(rtc_time_get() + ~0x0UL); /* configure deep sleep */ rtc_sleep_init(config); rtc_sleep_start(RTC_TIMER_TRIG_EN, 0); /* Restore CPU frequency */ rtc_clk_cpu_freq_set(cpu_freq); /* resume UARTs */ for (int i = 0; i < 3; ++i) { REG_CLR_BIT(UART_FLOW_CONF_REG(i), UART_FORCE_XOFF); REG_SET_BIT(UART_FLOW_CONF_REG(i), UART_FORCE_XON); REG_CLR_BIT(UART_FLOW_CONF_REG(i), UART_FORCE_XON); } }