// Copyright 2015-2019 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 <stdbool.h>
#include <stdint.h>
#include <stddef.h>
#include <assert.h>
#include "sdkconfig.h"
#include "esp32s2beta/rom/ets_sys.h"
#include "esp32s2beta/rom/rtc.h"
#include "esp32s2beta/rom/uart.h"
#include "esp32s2beta/rom/gpio.h"
#include "soc/rtc.h"
#include "soc/rtc_cntl_reg.h"
#include "soc/rtc_io_reg.h"
#include "soc/sens_reg.h"
#include "soc/dport_reg.h"
#include "soc/efuse_reg.h"
#include "soc/apb_ctrl_reg.h"
#include "i2c_rtc_clk.h"
#include "soc_log.h"
#include "xtensa/core-macros.h"
#define MHZ (1000000)
/* Frequency of the 8M oscillator is 8.5MHz +/- 5%, at the default DCAP setting */
#define RTC_FAST_CLK_FREQ_8M 8500000
#define RTC_SLOW_CLK_FREQ_150K 150000
#define RTC_SLOW_CLK_FREQ_8MD256 (RTC_FAST_CLK_FREQ_8M / 256)
#define RTC_SLOW_CLK_FREQ_32K 32768
static const char *TAG = "rtc_clk";
/* Various constants related to the analog internals of the chip.
* Defined here because they don't have any use outside of this file.
*/
#define BBPLL_ENDIV5_VAL_320M 0x43
#define BBPLL_BBADC_DSMP_VAL_320M 0x84
#define BBPLL_ENDIV5_VAL_480M 0xc3
#define BBPLL_BBADC_DSMP_VAL_480M 0x74
#define APLL_SDM_STOP_VAL_1 0x09
#define APLL_SDM_STOP_VAL_2_REV0 0x69
#define APLL_SDM_STOP_VAL_2_REV1 0x49
#define APLL_CAL_DELAY_1 0x0f
#define APLL_CAL_DELAY_2 0x3f
#define APLL_CAL_DELAY_3 0x1f
#define XTAL_32K_DAC_VAL 1
#define XTAL_32K_DRES_VAL 3
#define XTAL_32K_DBIAS_VAL 0
#define XTAL_32K_BOOTSTRAP_DAC_VAL 3
#define XTAL_32K_BOOTSTRAP_DRES_VAL 3
#define XTAL_32K_BOOTSTRAP_DBIAS_VAL 0
#define XTAL_32K_BOOTSTRAP_TIME_US 7
/* Delays for various clock sources to be enabled/switched.
* All values are in microseconds.
* TODO: some of these are excessive, and should be reduced.
*/
#define DELAY_PLL_DBIAS_RAISE 3
#define DELAY_PLL_ENABLE_WITH_150K 80
#define DELAY_PLL_ENABLE_WITH_32K 160
#define DELAY_FAST_CLK_SWITCH 3
#define DELAY_SLOW_CLK_SWITCH 300
#define DELAY_8M_ENABLE 50
/* Number of 8M/256 clock cycles to use for XTAL frequency estimation.
* 10 cycles will take approximately 300 microseconds.
*/
#define XTAL_FREQ_EST_CYCLES 10
/* Core voltage needs to be increased in two cases:
* 1. running at 240 MHz
* 2. running with 80MHz Flash frequency
*/
#ifdef CONFIG_ESPTOOLPY_FLASHFREQ_80M
#define DIG_DBIAS_80M_160M RTC_CNTL_DBIAS_1V10
#else
#define DIG_DBIAS_80M_160M RTC_CNTL_DBIAS_1V10
#endif
#define DIG_DBIAS_240M RTC_CNTL_DBIAS_1V10
#define DIG_DBIAS_XTAL RTC_CNTL_DBIAS_1V10
#define DIG_DBIAS_2M RTC_CNTL_DBIAS_1V00
/* PLL currently enabled, if any */
typedef enum {
RTC_PLL_NONE,
RTC_PLL_320M,
RTC_PLL_480M
} rtc_pll_t;
static rtc_pll_t s_cur_pll = RTC_PLL_NONE;
/* Current CPU frequency; saved in a variable for faster freq. switching */
static rtc_cpu_freq_t s_cur_freq = RTC_CPU_FREQ_XTAL;
static void rtc_clk_32k_enable_internal(int dac, int dres, int dbias)
{
REG_SET_FIELD(RTC_CNTL_EXT_XTL_CONF_REG, RTC_CNTL_DAC_XTAL_32K, dac);
REG_SET_FIELD(RTC_CNTL_EXT_XTL_CONF_REG, RTC_CNTL_DRES_XTAL_32K, dres);
//FIXME: RTC_CNTL_DBIAS_XTAL_32K removed, do not know how to config at the moment
//REG_SET_FIELD(RTC_CNTL_EXT_XTL_CONF_REG, RTC_CNTL_DBIAS_XTAL_32K, dbias);
SET_PERI_REG_MASK(RTC_CNTL_EXT_XTL_CONF_REG, RTC_CNTL_XPD_XTAL_32K);
}
void rtc_clk_32k_enable(bool enable)
{
if (enable) {
rtc_clk_32k_enable_internal(XTAL_32K_DAC_VAL, XTAL_32K_DRES_VAL, XTAL_32K_DBIAS_VAL);
} else {
CLEAR_PERI_REG_MASK(RTC_CNTL_EXT_XTL_CONF_REG, RTC_CNTL_XPD_XTAL_32K);
}
}
/* Helping external 32kHz crystal to start up.
* External crystal connected to outputs GPIO32 GPIO33.
* Forms N pulses with a frequency of about 32KHz on the outputs of the crystal.
*/
void rtc_clk_32k_bootstrap(uint32_t cycle)
{
if (cycle) {
const uint32_t pin_32 = 32;
const uint32_t pin_33 = 33;
const uint32_t mask_32 = (1 << (pin_32 - 32));
const uint32_t mask_33 = (1 << (pin_33 - 32));
gpio_pad_select_gpio(pin_32);
gpio_pad_select_gpio(pin_33);
gpio_output_set_high(mask_32, mask_33, mask_32 | mask_33, 0);
const uint32_t delay_us = (1000000 / RTC_SLOW_CLK_FREQ_32K / 2);
while (cycle) {
gpio_output_set_high(mask_32, mask_33, mask_32 | mask_33, 0);
ets_delay_us(delay_us);
gpio_output_set_high(mask_33, mask_32, mask_32 | mask_33, 0);
ets_delay_us(delay_us);
cycle--;
}
gpio_output_set_high(0, 0, 0, mask_32 | mask_33); // disable pins
}
CLEAR_PERI_REG_MASK(RTC_CNTL_EXT_XTL_CONF_REG, RTC_CNTL_XPD_XTAL_32K);
}
bool rtc_clk_32k_enabled(void)
{
return GET_PERI_REG_MASK(RTC_CNTL_EXT_XTL_CONF_REG, RTC_CNTL_XPD_XTAL_32K) != 0;
}
void rtc_clk_8m_enable(bool clk_8m_en, bool d256_en)
{
if (clk_8m_en) {
CLEAR_PERI_REG_MASK(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_ENB_CK8M);
/* no need to wait once enabled by software */
REG_SET_FIELD(RTC_CNTL_TIMER1_REG, RTC_CNTL_CK8M_WAIT, 1);
if (d256_en) {
CLEAR_PERI_REG_MASK(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_ENB_CK8M_DIV);
} else {
SET_PERI_REG_MASK(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_ENB_CK8M_DIV);
}
ets_delay_us(DELAY_8M_ENABLE);
} else {
SET_PERI_REG_MASK(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_ENB_CK8M);
REG_SET_FIELD(RTC_CNTL_TIMER1_REG, RTC_CNTL_CK8M_WAIT, RTC_CNTL_CK8M_WAIT_DEFAULT);
}
}
bool rtc_clk_8m_enabled(void)
{
return GET_PERI_REG_MASK(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_ENB_CK8M) == 0;
}
bool rtc_clk_8md256_enabled(void)
{
return GET_PERI_REG_MASK(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_ENB_CK8M_DIV) == 0;
}
void rtc_clk_apll_enable(bool enable, uint32_t sdm0, uint32_t sdm1, uint32_t sdm2, uint32_t o_div)
{
REG_SET_FIELD(RTC_CNTL_ANA_CONF_REG, RTC_CNTL_PLLA_FORCE_PD, enable ? 0 : 1);
REG_SET_FIELD(RTC_CNTL_ANA_CONF_REG, RTC_CNTL_PLLA_FORCE_PU, enable ? 1 : 0);
if (enable) {
uint8_t sdm_stop_val_2 = APLL_SDM_STOP_VAL_2_REV1;
I2C_WRITEREG_MASK_RTC(I2C_APLL, I2C_APLL_DSDM2, sdm2);
I2C_WRITEREG_MASK_RTC(I2C_APLL, I2C_APLL_DSDM0, sdm0);
I2C_WRITEREG_MASK_RTC(I2C_APLL, I2C_APLL_DSDM1, sdm1);
I2C_WRITEREG_RTC(I2C_APLL, I2C_APLL_SDM_STOP, APLL_SDM_STOP_VAL_1);
I2C_WRITEREG_RTC(I2C_APLL, I2C_APLL_SDM_STOP, sdm_stop_val_2);
I2C_WRITEREG_MASK_RTC(I2C_APLL, I2C_APLL_OR_OUTPUT_DIV, o_div);
/* calibration */
I2C_WRITEREG_RTC(I2C_APLL, I2C_APLL_IR_CAL_DELAY, APLL_CAL_DELAY_1);
I2C_WRITEREG_RTC(I2C_APLL, I2C_APLL_IR_CAL_DELAY, APLL_CAL_DELAY_2);
I2C_WRITEREG_RTC(I2C_APLL, I2C_APLL_IR_CAL_DELAY, APLL_CAL_DELAY_3);
/* wait for calibration end */
while (!(I2C_READREG_MASK_RTC(I2C_APLL, I2C_APLL_OR_CAL_END))) {
/* use ets_delay_us so the RTC bus doesn't get flooded */
ets_delay_us(1);
}
}
}
void rtc_clk_slow_freq_set(rtc_slow_freq_t slow_freq)
{
REG_SET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_ANA_CLK_RTC_SEL, slow_freq);
REG_SET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_DIG_XTAL32K_EN,
(slow_freq == RTC_SLOW_FREQ_32K_XTAL) ? 1 : 0);
ets_delay_us(DELAY_SLOW_CLK_SWITCH);
}
rtc_slow_freq_t rtc_clk_slow_freq_get(void)
{
return REG_GET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_ANA_CLK_RTC_SEL);
}
uint32_t rtc_clk_slow_freq_get_hz(void)
{
switch (rtc_clk_slow_freq_get()) {
case RTC_SLOW_FREQ_RTC: return RTC_SLOW_CLK_FREQ_150K;
case RTC_SLOW_FREQ_32K_XTAL: return RTC_SLOW_CLK_FREQ_32K;
case RTC_SLOW_FREQ_8MD256: return RTC_SLOW_CLK_FREQ_8MD256;
}
return 0;
}
void rtc_clk_fast_freq_set(rtc_fast_freq_t fast_freq)
{
REG_SET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_FAST_CLK_RTC_SEL, fast_freq);
ets_delay_us(DELAY_FAST_CLK_SWITCH);
}
rtc_fast_freq_t rtc_clk_fast_freq_get(void)
{
return REG_GET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_FAST_CLK_RTC_SEL);
}
void rtc_clk_bbpll_set(rtc_xtal_freq_t xtal_freq, rtc_cpu_freq_t cpu_freq)
{
#if !CONFIG_IDF_ENV_FPGA
uint8_t div_ref;
uint8_t div7_0;
uint8_t dr1;
uint8_t dr3;
uint8_t dchgp;
uint8_t dcur;
if (cpu_freq != RTC_CPU_FREQ_240M) {
/* Configure 320M PLL */
switch (xtal_freq) {
case RTC_XTAL_FREQ_40M:
div_ref = 0;
div7_0 = 4;
dr1 = 0;
dr3 = 0;
dchgp = 5;
dcur = 4;
break;
case RTC_XTAL_FREQ_26M:
div_ref = 12;
div7_0 = 156;
dr1 = 3;
dr3 = 3;
dchgp = 4;
dcur = 1;
break;
case RTC_XTAL_FREQ_24M:
div_ref = 11;
div7_0 = 156;
dr1 = 3;
dr3 = 3;
dchgp = 4;
dcur = 1;
break;
default:
div_ref = 0;
div7_0 = 4;
dr1 = 0;
dr3 = 0;
dchgp = 5;
dcur = 4;
break;
}
I2C_WRITEREG_MASK_RTC(I2C_BBPLL, I2C_BBPLL_MODE_HF, 0);
I2C_WRITEREG_MASK_RTC(I2C_BBPLL, I2C_BBPLL_DIV_ADC, 2);
} else {
/* Raise the voltage */
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_DIG_DBIAS_WAK, RTC_CNTL_DBIAS_1V25);
ets_delay_us(DELAY_PLL_DBIAS_RAISE);
/* Configure 480M PLL */
switch (xtal_freq) {
case RTC_XTAL_FREQ_40M:
div_ref = 0;
div7_0 = 8;
dr1 = 0;
dr3 = 0;
dchgp = 5;
dcur = 5;
break;
case RTC_XTAL_FREQ_26M:
div_ref = 12;
div7_0 = 236;
dr1 = 3;
dr3 = 3;
dchgp = 0;
dcur = 2;
break;
case RTC_XTAL_FREQ_24M:
div_ref = 11;
div7_0 = 236;
dr1 = 3;
dr3 = 3;
dchgp = 0;
dcur = 2;
break;
default:
div_ref = 0;
div7_0 = 8;
dr1 = 0;
dr3 = 0;
dchgp = 5;
dcur = 5;
break;
}
I2C_WRITEREG_MASK_RTC(I2C_BBPLL, I2C_BBPLL_MODE_HF, 1);
I2C_WRITEREG_MASK_RTC(I2C_BBPLL, I2C_BBPLL_DIV_ADC, 2);
}
I2C_WRITEREG_MASK_RTC(I2C_BBPLL, I2C_BBPLL_OC_DCUR, dcur);
I2C_WRITEREG_MASK_RTC(I2C_BBPLL, I2C_BBPLL_OC_DR1, dr1);
I2C_WRITEREG_MASK_RTC(I2C_BBPLL, I2C_BBPLL_OC_DR3, dr3);
I2C_WRITEREG_MASK_RTC(I2C_BBPLL, I2C_BBPLL_OC_DCHGP, dchgp);
I2C_WRITEREG_MASK_RTC(I2C_BBPLL, I2C_BBPLL_OC_DIV_7_0, div7_0);
I2C_WRITEREG_MASK_RTC(I2C_BBPLL, I2C_BBPLL_OC_REF_DIV, div_ref);
uint32_t delay_pll_en = (rtc_clk_slow_freq_get() == RTC_SLOW_FREQ_RTC) ?
DELAY_PLL_ENABLE_WITH_150K : DELAY_PLL_ENABLE_WITH_32K;
ets_delay_us(delay_pll_en);
#endif
}
/**
* Switch to XTAL frequency. Does not disable the PLL.
*/
static void rtc_clk_cpu_freq_to_xtal(void)
{
rtc_xtal_freq_t xtal_freq = rtc_clk_xtal_freq_get();
ets_update_cpu_frequency(xtal_freq);
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_DIG_DBIAS_WAK, DIG_DBIAS_XTAL);
REG_SET_FIELD(APB_CTRL_SYSCLK_CONF_REG, APB_CTRL_PRE_DIV_CNT, 0);
REG_SET_FIELD(APB_CTRL_SYSCLK_CONF_REG, APB_CTRL_SOC_CLK_SEL, APB_CTRL_SOC_CLK_SEL_XTL);
DPORT_REG_WRITE(DPORT_CPU_PER_CONF_REG, 0); // clear DPORT_CPUPERIOD_SEL
rtc_clk_apb_freq_update(xtal_freq * MHZ);
s_cur_freq = RTC_CPU_FREQ_XTAL;
}
/**
* Switch to one of PLL-based frequencies. Current frequency can be XTAL or PLL.
* PLL must already be enabled.
* If switching between frequencies derived from different PLLs (320M and 480M),
* fall back to rtc_clk_cpu_freq_set.
* @param cpu_freq new CPU frequency
*/
static void rtc_clk_cpu_freq_to_pll(rtc_cpu_freq_t cpu_freq)
{
int freq = 0;
if (s_cur_pll == RTC_PLL_NONE ||
(cpu_freq == RTC_CPU_FREQ_240M && s_cur_pll == RTC_PLL_320M) ||
(cpu_freq != RTC_CPU_FREQ_240M && s_cur_pll == RTC_PLL_480M)) {
/* need to switch PLLs, fall back to full implementation */
rtc_clk_cpu_freq_set(cpu_freq);
return;
}
if (cpu_freq == RTC_CPU_FREQ_80M) {
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_DIG_DBIAS_WAK, DIG_DBIAS_80M_160M);
DPORT_REG_CLR_BIT(DPORT_CPU_PER_CONF_REG, DPORT_PLL_FREQ_SEL);
DPORT_REG_WRITE(DPORT_CPU_PER_CONF_REG, 0);
freq = 80;
} else if (cpu_freq == RTC_CPU_FREQ_160M) {
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_DIG_DBIAS_WAK, DIG_DBIAS_80M_160M);
DPORT_REG_CLR_BIT(DPORT_CPU_PER_CONF_REG, DPORT_PLL_FREQ_SEL);
DPORT_REG_WRITE(DPORT_CPU_PER_CONF_REG, 1);
freq = 160;
} else if (cpu_freq == RTC_CPU_FREQ_240M) {
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_DIG_DBIAS_WAK, DIG_DBIAS_240M);
DPORT_REG_SET_BIT(DPORT_CPU_PER_CONF_REG, DPORT_PLL_FREQ_SEL);
DPORT_REG_WRITE(DPORT_CPU_PER_CONF_REG, 2);
freq = 240;
}
REG_SET_FIELD(APB_CTRL_SYSCLK_CONF_REG, APB_CTRL_SOC_CLK_SEL, APB_CTRL_SOC_CLK_SEL_PLL);
rtc_clk_apb_freq_update(80 * MHZ);
ets_update_cpu_frequency(freq);
s_cur_freq = cpu_freq;
}
void rtc_clk_cpu_freq_set_fast(rtc_cpu_freq_t cpu_freq)
{
if (cpu_freq == s_cur_freq) {
return;
} else if (cpu_freq == RTC_CPU_FREQ_2M || s_cur_freq == RTC_CPU_FREQ_2M) {
/* fall back to full implementation if switch to/from 2M is needed */
rtc_clk_cpu_freq_set(cpu_freq);
} else if (cpu_freq == RTC_CPU_FREQ_XTAL) {
rtc_clk_cpu_freq_to_xtal();
} else if (cpu_freq > RTC_CPU_FREQ_XTAL) {
rtc_clk_cpu_freq_to_pll(cpu_freq);
rtc_clk_wait_for_slow_cycle();
}
}
void rtc_clk_cpu_freq_set(rtc_cpu_freq_t cpu_freq)
{
rtc_xtal_freq_t xtal_freq = rtc_clk_xtal_freq_get();
/* Switch CPU to XTAL frequency first */
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_DIG_DBIAS_WAK, DIG_DBIAS_XTAL);
REG_SET_FIELD(APB_CTRL_SYSCLK_CONF_REG, APB_CTRL_SOC_CLK_SEL, APB_CTRL_SOC_CLK_SEL_XTL);
REG_SET_FIELD(APB_CTRL_SYSCLK_CONF_REG, APB_CTRL_PRE_DIV_CNT, 0);
ets_update_cpu_frequency(xtal_freq);
/* Frequency switch is synchronized to SLOW_CLK cycle. Wait until the switch
* is complete before disabling the PLL.
*/
rtc_clk_wait_for_slow_cycle();
DPORT_REG_CLR_BIT(DPORT_CPU_PER_CONF_REG, DPORT_PLL_FREQ_SEL);
DPORT_REG_SET_FIELD(DPORT_CPU_PER_CONF_REG, DPORT_CPUPERIOD_SEL, 0);
SET_PERI_REG_MASK(RTC_CNTL_OPTIONS0_REG,
RTC_CNTL_BB_I2C_FORCE_PD | RTC_CNTL_BBPLL_FORCE_PD |
RTC_CNTL_BBPLL_I2C_FORCE_PD);
s_cur_pll = RTC_PLL_NONE;
rtc_clk_apb_freq_update(xtal_freq * MHZ);
/* now switch to the desired frequency */
if (cpu_freq == RTC_CPU_FREQ_XTAL) {
/* already at XTAL, nothing to do */
} else if (cpu_freq == RTC_CPU_FREQ_2M) {
/* set up divider to produce 2MHz from XTAL */
REG_SET_FIELD(APB_CTRL_SYSCLK_CONF_REG, APB_CTRL_PRE_DIV_CNT, (xtal_freq / 2) - 1);
ets_update_cpu_frequency(2);
rtc_clk_apb_freq_update(2 * MHZ);
/* lower the voltage */
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_DIG_DBIAS_WAK, DIG_DBIAS_2M);
} else {
/* use PLL as clock source */
rtc_clk_bbpll_set(xtal_freq, cpu_freq);
if (cpu_freq == RTC_CPU_FREQ_80M) {
DPORT_REG_CLR_BIT(DPORT_CPU_PER_CONF_REG, DPORT_PLL_FREQ_SEL);
DPORT_REG_SET_FIELD(DPORT_CPU_PER_CONF_REG, DPORT_CPUPERIOD_SEL, 0);
ets_update_cpu_frequency(80);
s_cur_pll = RTC_PLL_320M;
} else if (cpu_freq == RTC_CPU_FREQ_160M) {
DPORT_REG_CLR_BIT(DPORT_CPU_PER_CONF_REG, DPORT_PLL_FREQ_SEL);
DPORT_REG_SET_FIELD(DPORT_CPU_PER_CONF_REG, DPORT_CPUPERIOD_SEL, 1);
ets_update_cpu_frequency(160);
s_cur_pll = RTC_PLL_320M;
} else if (cpu_freq == RTC_CPU_FREQ_240M) {
DPORT_REG_SET_BIT(DPORT_CPU_PER_CONF_REG, DPORT_PLL_FREQ_SEL);
DPORT_REG_SET_FIELD(DPORT_CPU_PER_CONF_REG, DPORT_CPUPERIOD_SEL, 2);
ets_update_cpu_frequency(240);
s_cur_pll = RTC_PLL_480M;
}
REG_SET_FIELD(APB_CTRL_SYSCLK_CONF_REG, APB_CTRL_SOC_CLK_SEL, APB_CTRL_SOC_CLK_SEL_PLL);
rtc_clk_wait_for_slow_cycle();
rtc_clk_apb_freq_update(80 * MHZ);
}
s_cur_freq = cpu_freq;
}
rtc_cpu_freq_t rtc_clk_cpu_freq_get(void)
{
uint32_t soc_clk_sel = REG_GET_FIELD(APB_CTRL_SYSCLK_CONF_REG, APB_CTRL_SOC_CLK_SEL);
switch (soc_clk_sel) {
case APB_CTRL_SOC_CLK_SEL_XTL: {
uint32_t pre_div = REG_GET_FIELD(APB_CTRL_SYSCLK_CONF_REG, APB_CTRL_PRE_DIV_CNT);
if (pre_div == 0) {
return RTC_CPU_FREQ_XTAL;
} else if (pre_div == rtc_clk_xtal_freq_get() / 2 - 1) {
return RTC_CPU_FREQ_2M;
} else {
assert(false && "unsupported frequency");
}
break;
}
case APB_CTRL_SOC_CLK_SEL_PLL: {
uint32_t cpuperiod_sel = DPORT_REG_GET_FIELD(DPORT_CPU_PER_CONF_REG, DPORT_CPUPERIOD_SEL);
if (cpuperiod_sel == 0) {
return RTC_CPU_FREQ_80M;
} else if (cpuperiod_sel == 1) {
return RTC_CPU_FREQ_160M;
} else if (cpuperiod_sel == 2) {
return RTC_CPU_FREQ_240M;
} else {
assert(false && "unsupported frequency");
}
break;
}
case APB_CTRL_SOC_CLK_SEL_APLL:
case APB_CTRL_SOC_CLK_SEL_8M:
default:
assert(false && "unsupported frequency");
}
return APB_CTRL_SOC_CLK_SEL_XTL;
}
uint32_t rtc_clk_cpu_freq_value(rtc_cpu_freq_t cpu_freq)
{
switch (cpu_freq) {
case RTC_CPU_FREQ_XTAL:
return ((uint32_t) rtc_clk_xtal_freq_get()) * MHZ;
case RTC_CPU_FREQ_2M:
return 2 * MHZ;
case RTC_CPU_FREQ_80M:
return 80 * MHZ;
case RTC_CPU_FREQ_160M:
return 160 * MHZ;
case RTC_CPU_FREQ_240M:
return 240 * MHZ;
default:
assert(false && "invalid rtc_cpu_freq_t value");
return 0;
}
}
bool rtc_clk_cpu_freq_from_mhz(int mhz, rtc_cpu_freq_t *out_val)
{
if (mhz == 240) {
*out_val = RTC_CPU_FREQ_240M;
} else if (mhz == 160) {
*out_val = RTC_CPU_FREQ_160M;
} else if (mhz == 80) {
*out_val = RTC_CPU_FREQ_80M;
} else if (mhz == (int) rtc_clk_xtal_freq_get()) {
*out_val = RTC_CPU_FREQ_XTAL;
} else if (mhz == 2) {
*out_val = RTC_CPU_FREQ_2M;
} else {
return false;
}
return true;
}
/* Values of RTC_XTAL_FREQ_REG and RTC_APB_FREQ_REG are stored as two copies in
* lower and upper 16-bit halves. These are the routines to work with such a
* representation.
*/
static bool clk_val_is_valid(uint32_t val)
{
return (val & 0xffff) == ((val >> 16) & 0xffff) &&
val != 0 &&
val != UINT32_MAX;
}
static uint32_t reg_val_to_clk_val(uint32_t val)
{
return val & UINT16_MAX;
}
static uint32_t clk_val_to_reg_val(uint32_t val)
{
return (val & UINT16_MAX) | ((val & UINT16_MAX) << 16);
}
rtc_xtal_freq_t rtc_clk_xtal_freq_get(void)
{
/* We may have already written XTAL value into RTC_XTAL_FREQ_REG */
uint32_t xtal_freq_reg = READ_PERI_REG(RTC_XTAL_FREQ_REG);
if (!clk_val_is_valid(xtal_freq_reg)) {
SOC_LOGW(TAG, "invalid RTC_XTAL_FREQ_REG value: 0x%08x", xtal_freq_reg);
return RTC_XTAL_FREQ_40M;
}
return reg_val_to_clk_val(xtal_freq_reg);
}
void rtc_clk_xtal_freq_update(rtc_xtal_freq_t xtal_freq)
{
WRITE_PERI_REG(RTC_XTAL_FREQ_REG, clk_val_to_reg_val(xtal_freq));
}
static rtc_xtal_freq_t rtc_clk_xtal_freq_estimate(void)
{
/* Enable 8M/256 clock if needed */
const bool clk_8m_enabled = rtc_clk_8m_enabled();
const bool clk_8md256_enabled = rtc_clk_8md256_enabled();
if (!clk_8md256_enabled) {
rtc_clk_8m_enable(true, true);
}
uint64_t cal_val = rtc_clk_cal_ratio(RTC_CAL_8MD256, XTAL_FREQ_EST_CYCLES);
/* cal_val contains period of 8M/256 clock in XTAL clock cycles
* (shifted by RTC_CLK_CAL_FRACT bits).
* Xtal frequency will be (cal_val * 8M / 256) / 2^19
*/
uint32_t freq_mhz = (cal_val * RTC_FAST_CLK_FREQ_APPROX / MHZ / 256 ) >> RTC_CLK_CAL_FRACT;
/* Guess the XTAL type. For now, only 40 and 26MHz are supported.
*/
switch (freq_mhz) {
case 21 ... 31:
return RTC_XTAL_FREQ_26M;
case 32 ... 33:
SOC_LOGW(TAG, "Potentially bogus XTAL frequency: %d MHz, guessing 26 MHz", freq_mhz);
return RTC_XTAL_FREQ_26M;
case 34 ... 35:
SOC_LOGW(TAG, "Potentially bogus XTAL frequency: %d MHz, guessing 40 MHz", freq_mhz);
return RTC_XTAL_FREQ_40M;
case 36 ... 45:
return RTC_XTAL_FREQ_40M;
default:
SOC_LOGW(TAG, "Bogus XTAL frequency: %d MHz", freq_mhz);
return RTC_XTAL_FREQ_AUTO;
}
/* Restore 8M and 8md256 clocks to original state */
rtc_clk_8m_enable(clk_8m_enabled, clk_8md256_enabled);
}
void rtc_clk_apb_freq_update(uint32_t apb_freq)
{
WRITE_PERI_REG(RTC_APB_FREQ_REG, clk_val_to_reg_val(apb_freq >> 12));
}
uint32_t rtc_clk_apb_freq_get(void)
{
uint32_t freq_hz = reg_val_to_clk_val(READ_PERI_REG(RTC_APB_FREQ_REG)) << 12;
// round to the nearest MHz
freq_hz += MHZ / 2;
uint32_t remainder = freq_hz % MHZ;
return freq_hz - remainder;
}
void rtc_clk_init(rtc_clk_config_t cfg)
{
rtc_cpu_freq_t cpu_source_before = rtc_clk_cpu_freq_get();
/* If we get a TG WDT system reset while running at 240MHz,
* DPORT_CPUPERIOD_SEL register will be reset to 0 resulting in 120MHz
* APB and CPU frequencies after reset. This will cause issues with XTAL
* frequency estimation, so we switch to XTAL frequency first.
*
* Ideally we would only do this if APB_CTRL_SOC_CLK_SEL == PLL and
* PLL is configured for 480M, but it takes less time to switch to 40M and
* run the following code than querying the PLL does.
*/
if (REG_GET_FIELD(RTC_CNTL_CLK_CONF_REG, APB_CTRL_SOC_CLK_SEL) == APB_CTRL_SOC_CLK_SEL_PLL) {
rtc_clk_cpu_freq_set(RTC_CPU_FREQ_XTAL);
}
CLEAR_PERI_REG_MASK(RTC_CNTL_SLOW_CLK_CONF_REG, RTC_CNTL_ANA_CLK_DIV_VLD);
REG_SET_FIELD(RTC_CNTL_SLOW_CLK_CONF_REG, RTC_CNTL_ANA_CLK_DIV, 0);
SET_PERI_REG_MASK(RTC_CNTL_SLOW_CLK_CONF_REG, RTC_CNTL_ANA_CLK_DIV_VLD);
/* Set tuning parameters for 8M and 150k clocks.
* Note: this doesn't attempt to set the clocks to precise frequencies.
* Instead, we calibrate these clocks against XTAL frequency later, when necessary.
* - SCK_DCAP value controls tuning of 150k clock.
* The higher the value of DCAP is, the lower is the frequency.
* - CK8M_DFREQ value controls tuning of 8M clock.
* CLK_8M_DFREQ constant gives the best temperature characteristics.
*/
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_SCK_DCAP, cfg.slow_clk_dcap);
REG_SET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_CK8M_DFREQ, cfg.clk_8m_dfreq);
/* Configure 8M clock division */
REG_SET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_CK8M_DIV_SEL, cfg.clk_8m_div);
/* Enable the internal bus used to configure PLLs */
SET_PERI_REG_BITS(ANA_CONFIG_REG, ANA_CONFIG_M, ANA_CONFIG_M, ANA_CONFIG_S);
CLEAR_PERI_REG_MASK(ANA_CONFIG_REG, I2C_APLL_M | I2C_BBPLL_M);
rtc_xtal_freq_t xtal_freq = cfg.xtal_freq;
if (xtal_freq == RTC_XTAL_FREQ_AUTO) {
if (clk_val_is_valid(READ_PERI_REG(RTC_XTAL_FREQ_REG))) {
/* XTAL frequency has already been set, use existing value */
xtal_freq = rtc_clk_xtal_freq_get();
} else {
/* Not set yet, estimate XTAL frequency based on RTC_FAST_CLK */
xtal_freq = rtc_clk_xtal_freq_estimate();
if (xtal_freq == RTC_XTAL_FREQ_AUTO) {
SOC_LOGW(TAG, "Can't estimate XTAL frequency, assuming 26MHz");
xtal_freq = RTC_XTAL_FREQ_26M;
}
}
} else if (!clk_val_is_valid(READ_PERI_REG(RTC_XTAL_FREQ_REG))) {
/* Exact frequency was set in sdkconfig, but still warn if autodetected
* frequency is different. If autodetection failed, worst case we get a
* bit of garbage output.
*/
rtc_xtal_freq_t est_xtal_freq = rtc_clk_xtal_freq_estimate();
if (est_xtal_freq != xtal_freq) {
SOC_LOGW(TAG, "Possibly invalid CONFIG_ESP32_XTAL_FREQ setting (%dMHz). Detected %d MHz.",
xtal_freq, est_xtal_freq);
}
}
uart_tx_wait_idle(0);
rtc_clk_xtal_freq_update(xtal_freq);
rtc_clk_apb_freq_update(xtal_freq * MHZ);
/* Set CPU frequency */
rtc_clk_cpu_freq_set(cfg.cpu_freq);
/* Re-calculate the ccount to make time calculation correct. */
uint32_t freq_before = rtc_clk_cpu_freq_value(cpu_source_before) / MHZ;
uint32_t freq_after = rtc_clk_cpu_freq_value(cfg.cpu_freq) / MHZ;
XTHAL_SET_CCOUNT( XTHAL_GET_CCOUNT() * freq_after / freq_before );
/* Slow & fast clocks setup */
if (cfg.slow_freq == RTC_SLOW_FREQ_32K_XTAL) {
rtc_clk_32k_enable(true);
}
if (cfg.fast_freq == RTC_FAST_FREQ_8M) {
bool need_8md256 = cfg.slow_freq == RTC_SLOW_FREQ_8MD256;
rtc_clk_8m_enable(true, need_8md256);
}
rtc_clk_fast_freq_set(cfg.fast_freq);
rtc_clk_slow_freq_set(cfg.slow_freq);
}
/* Name used in libphy.a:phy_chip_v7.o
* TODO: update the library to use rtc_clk_xtal_freq_get
*/
rtc_xtal_freq_t rtc_get_xtal(void) __attribute__((alias("rtc_clk_xtal_freq_get")));