esp-idf/components/esp32/cpu_freq.c

80 wiersze
2.1 KiB
C

// Copyright 2015-2016 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 <stdint.h>
#include "rom/ets_sys.h"
#include "rom/uart.h"
#include "sdkconfig.h"
typedef enum{
XTAL_40M = 40,
XTAL_26M = 26,
XTAL_24M = 24,
XTAL_AUTO = 0
} xtal_freq_t;
typedef enum{
CPU_80M = 1,
CPU_160M = 2,
CPU_240M = 3,
} cpu_freq_t;
extern void phy_get_romfunc_addr();
// TODO: these functions need to be moved from librtc to ESP-IDF
extern void rtc_init_lite();
extern void rtc_set_cpu_freq(xtal_freq_t xtal_freq, cpu_freq_t cpu_freq);
/*
* 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_set_cpu_freq(void)
{
uint32_t freq_mhz = CONFIG_ESP32_DEFAULT_CPU_FREQ_MHZ;
phy_get_romfunc_addr();
// freq will be changed to 40MHz in rtc_init_lite,
// wait uart tx finish, otherwise some uart output will be lost
uart_tx_wait_idle(0);
rtc_init_lite();
cpu_freq_t freq = CPU_80M;
switch(freq_mhz) {
case 240:
freq = CPU_240M;
break;
case 160:
freq = CPU_160M;
break;
default:
freq_mhz = 80;
/* no break */
case 80:
freq = CPU_80M;
break;
}
// freq will be changed to freq in rtc_set_cpu_freq,
// wait uart tx finish, otherwise some uart output will be lost
uart_tx_wait_idle(0);
rtc_set_cpu_freq(XTAL_AUTO, freq);
ets_update_cpu_frequency(freq_mhz);
}