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Merge branch 'feature/rtc_cpu_freq_config' into 'master'

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soc/rtc: Refactoring, support CPU frequencies lower than XTAL

See merge request idf/esp-idf!2856
This commit is contained in:
Ivan Grokhotkov
2018-08-22 11:32:08 +08:00
parent 4eb28b9ace e3d76d13b4
commit 90f5456dba
21 changed files with 889 additions and 509 deletions
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2
components/soc/component.mk
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@@ -4,3 +4,5 @@ SOC_NAME := esp32
COMPONENT_SRCDIRS := $(SOC_NAME) src/
COMPONENT_ADD_INCLUDEDIRS := $(SOC_NAME)/include include
-include $(COMPONENT_PATH)/$(SOC_NAME)/component.mk

1
components/soc/esp32/component.mk Normal file
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@@ -0,0 +1 @@
esp32/rtc_clk.o: CFLAGS += -fno-jump-tables -fno-tree-switch-conversion

130
components/soc/esp32/include/soc/rtc.h
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@@ -75,6 +75,26 @@ typedef enum {
RTC_CPU_FREQ_2M = 4, //!< 2 MHz
} rtc_cpu_freq_t;
/**
* @brief CPU clock source
*/
typedef enum {
RTC_CPU_FREQ_SRC_XTAL, //!< XTAL
RTC_CPU_FREQ_SRC_PLL, //!< PLL (480M or 320M)
RTC_CPU_FREQ_SRC_8M, //!< Internal 8M RTC oscillator
RTC_CPU_FREQ_SRC_APLL //!< APLL
} rtc_cpu_freq_src_t;
/**
* @brief CPU clock configuration structure
*/
typedef struct {
rtc_cpu_freq_src_t source; //!< The clock from which CPU clock is derived
uint32_t source_freq_mhz; //!< Source clock frequency
uint32_t div; //!< Divider, freq_mhz = source_freq_mhz / div
uint32_t freq_mhz; //!< CPU clock frequency
} rtc_cpu_freq_config_t;
/**
* @brief RTC SLOW_CLK frequency values
*/
@@ -108,13 +128,13 @@ typedef enum {
* Initialization parameters for rtc_clk_init
*/
typedef struct {
rtc_xtal_freq_t xtal_freq : 8; //!< Main XTAL frequency
rtc_cpu_freq_t cpu_freq : 3; //!< CPU frequency to set
rtc_fast_freq_t fast_freq : 1; //!< RTC_FAST_CLK frequency to set
rtc_slow_freq_t slow_freq : 2; //!< RTC_SLOW_CLK frequency to set
uint32_t clk_8m_div : 3; //!< RTC 8M clock divider (division is by clk_8m_div+1, i.e. 0 means 8MHz frequency)
uint32_t slow_clk_dcap : 8; //!< RTC 150k clock adjustment parameter (higher value leads to lower frequency)
uint32_t clk_8m_dfreq : 8; //!< RTC 8m clock adjustment parameter (higher value leads to higher frequency)
rtc_xtal_freq_t xtal_freq : 8; //!< Main XTAL frequency
rtc_cpu_freq_t cpu_freq_mhz : 10; //!< CPU frequency to set, in MHz
rtc_fast_freq_t fast_freq : 1; //!< RTC_FAST_CLK frequency to set
rtc_slow_freq_t slow_freq : 2; //!< RTC_SLOW_CLK frequency to set
uint32_t clk_8m_div : 3; //!< RTC 8M clock divider (division is by clk_8m_div+1, i.e. 0 means 8MHz frequency)
uint32_t slow_clk_dcap : 8; //!< RTC 150k clock adjustment parameter (higher value leads to lower frequency)
uint32_t clk_8m_dfreq : 8; //!< RTC 8m clock adjustment parameter (higher value leads to higher frequency)
} rtc_clk_config_t;
/**
@@ -122,7 +142,7 @@ typedef struct {
*/
#define RTC_CLK_CONFIG_DEFAULT() { \
.xtal_freq = RTC_XTAL_FREQ_AUTO, \
.cpu_freq = RTC_CPU_FREQ_80M, \
.cpu_freq_mhz = 80, \
.fast_freq = RTC_FAST_FREQ_8M, \
.slow_freq = RTC_SLOW_FREQ_RTC, \
.clk_8m_div = 0, \
@@ -281,6 +301,9 @@ rtc_fast_freq_t rtc_clk_fast_freq_get();
/**
* @brief Switch CPU frequency
*
* @note This function is deprecated and will be removed.
* See rtc_clk_cpu_freq_config_set instead.
*
* If a PLL-derived frequency is requested (80, 160, 240 MHz), this function
* will enable the PLL. Otherwise, PLL will be disabled.
* Note: this function is not optimized for switching speed. It may take several
@@ -288,11 +311,14 @@ rtc_fast_freq_t rtc_clk_fast_freq_get();
*
* @param cpu_freq new CPU frequency
*/
void rtc_clk_cpu_freq_set(rtc_cpu_freq_t cpu_freq);
void rtc_clk_cpu_freq_set(rtc_cpu_freq_t cpu_freq) __attribute__((deprecated));
/**
* @brief Switch CPU frequency
*
* @note This function is deprecated and will be removed.
* See rtc_clk_cpu_freq_set_config_fast instead.
*
* This is a faster version of rtc_clk_cpu_freq_set, which can handle some of
* the frequency switch paths (XTAL -> PLL, PLL -> XTAL).
* When switching from PLL to XTAL, PLL is not disabled (unlike rtc_clk_cpu_freq_set).
@@ -307,11 +333,14 @@ void rtc_clk_cpu_freq_set(rtc_cpu_freq_t cpu_freq);
*
* @param cpu_freq new CPU frequency
*/
void rtc_clk_cpu_freq_set_fast(rtc_cpu_freq_t cpu_freq);
void rtc_clk_cpu_freq_set_fast(rtc_cpu_freq_t cpu_freq) __attribute__((deprecated));
/**
* @brief Get the currently selected CPU frequency
*
* @note This function is deprecated and will be removed.
* See rtc_clk_cpu_freq_get_config instead.
*
* Although CPU can be clocked by APLL and RTC 8M sources, such support is not
* exposed through this library. As such, this function will not return
* meaningful values when these clock sources are configured (e.g. using direct
@@ -320,22 +349,97 @@ void rtc_clk_cpu_freq_set_fast(rtc_cpu_freq_t cpu_freq);
*
* @return CPU frequency (one of rtc_cpu_freq_t values)
*/
rtc_cpu_freq_t rtc_clk_cpu_freq_get();
rtc_cpu_freq_t rtc_clk_cpu_freq_get() __attribute__((deprecated));
/**
* @brief Get corresponding frequency value for rtc_cpu_freq_t enum value
*
* @note This function is deprecated and will be removed.
* See rtc_clk_cpu_freq_get/set_config instead.
*
* @param cpu_freq CPU frequency, on of rtc_cpu_freq_t values
* @return CPU frequency, in HZ
*/
uint32_t rtc_clk_cpu_freq_value(rtc_cpu_freq_t cpu_freq);
uint32_t rtc_clk_cpu_freq_value(rtc_cpu_freq_t cpu_freq) __attribute__((deprecated));
/**
* @brief Get rtc_cpu_freq_t enum value for given CPU frequency
*
* @note This function is deprecated and will be removed.
* See rtc_clk_cpu_freq_mhz_to_config instead.
*
* @param cpu_freq_mhz CPU frequency, one of 80, 160, 240, 2, and XTAL frequency
* @param[out] out_val output, rtc_cpu_freq_t value corresponding to the frequency
* @return true if the given frequency value matches one of enum values
*/
bool rtc_clk_cpu_freq_from_mhz(int cpu_freq_mhz, rtc_cpu_freq_t* out_val);
bool rtc_clk_cpu_freq_from_mhz(int cpu_freq_mhz, rtc_cpu_freq_t* out_val) __attribute__((deprecated));
/**
* @brief Get CPU frequency config corresponding to a rtc_cpu_freq_t value
* @param cpu_freq CPU frequency enumeration value
* @param[out] out_config Output, CPU frequency configuration structure
*/
void rtc_clk_cpu_freq_to_config(rtc_cpu_freq_t cpu_freq, rtc_cpu_freq_config_t* out_config);
/**
* @brief Get CPU frequency config for a given frequency
* @param freq_mhz Frequency in MHz
* @param[out] out_config Output, CPU frequency configuration structure
* @return true if frequency can be obtained, false otherwise
*/
bool rtc_clk_cpu_freq_mhz_to_config(uint32_t freq_mhz, rtc_cpu_freq_config_t* out_config);
/**
* @brief Switch CPU frequency
*
* This function sets CPU frequency according to the given configuration
* structure. It enables PLLs, if necessary.
*
* @note This function in not intended to be called by applications in FreeRTOS
* environment. This is because it does not adjust various timers based on the
* new CPU frequency.
*
* @param config CPU frequency configuration structure
*/
void rtc_clk_cpu_freq_set_config(const rtc_cpu_freq_config_t* config);
/**
* @brief Switch CPU frequency (optimized for speed)
*
* This function is a faster equivalent of rtc_clk_cpu_freq_set_config.
* It works faster because it does not disable PLLs when switching from PLL to
* XTAL and does not enabled them when switching back. If PLL is not already
* enabled when this function is called to switch from XTAL to PLL frequency,
* or the PLL which is enabled is the wrong one, this function will fall back
* to calling rtc_clk_cpu_freq_set_config.
*
* Unlike rtc_clk_cpu_freq_set_config, this function relies on static data,
* so it is less safe to use it e.g. from a panic handler (when memory might
* be corrupted).
*
* @note This function in not intended to be called by applications in FreeRTOS
* environment. This is because it does not adjust various timers based on the
* new CPU frequency.
*
* @param config CPU frequency configuration structure
*/
void rtc_clk_cpu_freq_set_config_fast(const rtc_cpu_freq_config_t* config);
/**
* @brief Get the currently used CPU frequency configuration
* @param[out] out_config Output, CPU frequency configuration structure
*/
void rtc_clk_cpu_freq_get_config(rtc_cpu_freq_config_t* out_config);
/**
* @brief Switch CPU clock source to XTAL
*
* Short form for filling in rtc_cpu_freq_config_t structure and calling
* rtc_clk_cpu_freq_set_config when a switch to XTAL is needed.
* Assumes that XTAL frequency has been determined — don't call in startup code.
*/
void rtc_clk_cpu_freq_set_xtal();
/**
* @brief Store new APB frequency value into RTC_APB_FREQ_REG

582
components/soc/esp32/rtc_clk.c
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@@ -16,6 +16,7 @@
#include <stdint.h>
#include <stddef.h>
#include <assert.h>
#include <stdlib.h>
#include "rom/ets_sys.h"
#include "rom/rtc.h"
#include "rom/uart.h"
@@ -31,9 +32,7 @@
#include "soc_log.h"
#include "sdkconfig.h"
#include "xtensa/core-macros.h"
#define MHZ (1000000)
#include "rtc_clk_common.h"
/* Frequency of the 8M oscillator is 8.5MHz +/- 5%, at the default DCAP setting */
#define RTC_FAST_CLK_FREQ_8M 8500000
@@ -41,12 +40,6 @@
#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
@@ -80,11 +73,6 @@ static const char* TAG = "rtc_clk";
#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
@@ -98,17 +86,17 @@ static const char* TAG = "rtc_clk";
#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;
#define RTC_PLL_FREQ_320M 320
#define RTC_PLL_FREQ_480M 480
/* 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_cpu_freq_to_8m();
static void rtc_clk_bbpll_disable();
static void rtc_clk_bbpll_enable();
static void rtc_clk_cpu_freq_to_pll_mhz(int cpu_freq_mhz);
static bool rtc_clk_cpu_freq_from_mhz_internal(int mhz, rtc_cpu_freq_t* out_val);
// Current PLL frequency, in MHZ (320 or 480). Zero if PLL is not enabled.
static int s_cur_pll_freq;
static void rtc_clk_32k_enable_internal(int dac, int dres, int dbias)
{
@@ -275,7 +263,7 @@ rtc_fast_freq_t rtc_clk_fast_freq_get()
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)
void rtc_clk_bbpll_configure(rtc_xtal_freq_t xtal_freq, int pll_freq)
{
uint8_t div_ref;
uint8_t div7_0;
@@ -284,7 +272,7 @@ void rtc_clk_bbpll_set(rtc_xtal_freq_t xtal_freq, rtc_cpu_freq_t cpu_freq)
uint8_t dcur;
uint8_t bw;
if (cpu_freq != RTC_CPU_FREQ_240M) {
if (pll_freq == RTC_PLL_FREQ_320M) {
/* Raise the voltage, if needed */
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_DIG_DBIAS_WAK, DIG_DBIAS_80M_160M);
/* Configure 320M PLL */
@@ -376,96 +364,47 @@ void rtc_clk_bbpll_set(rtc_xtal_freq_t xtal_freq, rtc_cpu_freq_t cpu_freq)
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);
s_cur_pll_freq = pll_freq;
}
/**
* Switch to XTAL frequency. Does not disable the PLL.
*/
static void rtc_clk_cpu_freq_to_xtal()
void rtc_clk_cpu_freq_to_xtal(int freq, int div)
{
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(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_SOC_CLK_SEL, RTC_CNTL_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_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_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_WRITE(DPORT_CPU_PER_CONF_REG, 2);
freq = 240;
}
REG_SET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_SOC_CLK_SEL, RTC_CNTL_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();
/* set divider from XTAL to APB clock */
REG_SET_FIELD(APB_CTRL_SYSCLK_CONF_REG, APB_CTRL_PRE_DIV_CNT, div - 1);
/* adjust ref_tick */
REG_WRITE(APB_CTRL_XTAL_TICK_CONF_REG, freq * MHZ / REF_CLK_FREQ - 1);
/* switch clock source */
REG_SET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_SOC_CLK_SEL, RTC_CNTL_SOC_CLK_SEL_XTL);
DPORT_REG_WRITE(DPORT_CPU_PER_CONF_REG, 0); /* clear DPORT_CPUPERIOD_SEL */
rtc_clk_apb_freq_update(freq * MHZ);
/* lower the voltage */
if (freq <= 2) {
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_DIG_DBIAS_WAK, DIG_DBIAS_2M);
} else {
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_DIG_DBIAS_WAK, DIG_DBIAS_XTAL);
}
}
void rtc_clk_cpu_freq_set(rtc_cpu_freq_t cpu_freq)
static void rtc_clk_cpu_freq_to_8m()
{
rtc_xtal_freq_t xtal_freq = rtc_clk_xtal_freq_get();
/* Switch CPU to XTAL frequency first */
ets_update_cpu_frequency(8);
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_DIG_DBIAS_WAK, DIG_DBIAS_XTAL);
REG_SET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_SOC_CLK_SEL, RTC_CNTL_SOC_CLK_SEL_XTL);
REG_SET_FIELD(APB_CTRL_SYSCLK_CONF_REG, APB_CTRL_PRE_DIV_CNT, 0);
ets_update_cpu_frequency(xtal_freq);
REG_SET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_SOC_CLK_SEL, RTC_CNTL_SOC_CLK_SEL_8M);
DPORT_REG_WRITE(DPORT_CPU_PER_CONF_REG, 0); // clear DPORT_CPUPERIOD_SEL
rtc_clk_apb_freq_update(RTC_FAST_CLK_FREQ_8M);
}
/* 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_SET_FIELD(DPORT_CPU_PER_CONF_REG, DPORT_CPUPERIOD_SEL, 0);
static void rtc_clk_bbpll_disable()
{
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);
s_cur_pll_freq = 0;
/* is APLL under force power down? */
uint32_t apll_fpd = REG_GET_FIELD(RTC_CNTL_ANA_CONF_REG, RTC_CNTL_PLLA_FORCE_PD);
@@ -473,76 +412,73 @@ void rtc_clk_cpu_freq_set(rtc_cpu_freq_t cpu_freq)
/* then also power down the internal I2C bus */
SET_PERI_REG_MASK(RTC_CNTL_OPTIONS0_REG, RTC_CNTL_BIAS_I2C_FORCE_PD);
}
/* 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);
}
static void rtc_clk_bbpll_enable()
{
CLEAR_PERI_REG_MASK(RTC_CNTL_OPTIONS0_REG,
RTC_CNTL_BIAS_I2C_FORCE_PD | RTC_CNTL_BB_I2C_FORCE_PD |
RTC_CNTL_BBPLL_FORCE_PD | RTC_CNTL_BBPLL_I2C_FORCE_PD);
}
/**
* Switch to one of PLL-based frequencies. Current frequency can be XTAL or PLL.
* PLL must already be enabled.
* @param cpu_freq new CPU frequency
*/
static void rtc_clk_cpu_freq_to_pll_mhz(int cpu_freq_mhz)
{
int dbias = DIG_DBIAS_80M_160M;
int per_conf = 0;
if (cpu_freq_mhz == 80) {
/* nothing to do */
} else if (cpu_freq_mhz == 160) {
per_conf = 1;
} else if (cpu_freq_mhz == 240) {
dbias = DIG_DBIAS_240M;
per_conf = 2;
} else {
/* use PLL as clock source */
CLEAR_PERI_REG_MASK(RTC_CNTL_OPTIONS0_REG,
RTC_CNTL_BIAS_I2C_FORCE_PD | RTC_CNTL_BB_I2C_FORCE_PD |
RTC_CNTL_BBPLL_FORCE_PD | RTC_CNTL_BBPLL_I2C_FORCE_PD);
rtc_clk_bbpll_set(xtal_freq, cpu_freq);
if (cpu_freq == RTC_CPU_FREQ_80M) {
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_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_FIELD(DPORT_CPU_PER_CONF_REG, DPORT_CPUPERIOD_SEL, 2);
ets_update_cpu_frequency(240);
s_cur_pll = RTC_PLL_480M;
}
REG_SET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_SOC_CLK_SEL, RTC_CNTL_SOC_CLK_SEL_PLL);
rtc_clk_wait_for_slow_cycle();
rtc_clk_apb_freq_update(80 * MHZ);
assert(false && "invalid frequency");
}
s_cur_freq = cpu_freq;
DPORT_REG_WRITE(DPORT_CPU_PER_CONF_REG, per_conf);
REG_SET_FIELD(RTC_CNTL_REG, RTC_CNTL_DIG_DBIAS_WAK, dbias);
REG_SET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_SOC_CLK_SEL, RTC_CNTL_SOC_CLK_SEL_PLL);
rtc_clk_apb_freq_update(80 * MHZ);
ets_update_cpu_frequency(cpu_freq_mhz);
rtc_clk_wait_for_slow_cycle();
}
void rtc_clk_cpu_freq_set(rtc_cpu_freq_t cpu_freq)
{
rtc_cpu_freq_config_t config;
rtc_clk_cpu_freq_to_config(cpu_freq, &config);
rtc_clk_cpu_freq_set_config(&config);
}
void rtc_clk_cpu_freq_set_fast(rtc_cpu_freq_t cpu_freq)
{
rtc_cpu_freq_config_t config;
rtc_clk_cpu_freq_to_config(cpu_freq, &config);
rtc_clk_cpu_freq_set_config_fast(&config);
}
void rtc_clk_cpu_freq_set_xtal()
{
int freq_mhz = (int) rtc_clk_xtal_freq_get();
rtc_clk_cpu_freq_to_xtal(freq_mhz, 1);
rtc_clk_wait_for_slow_cycle();
rtc_clk_bbpll_disable();
}
rtc_cpu_freq_t rtc_clk_cpu_freq_get()
{
uint32_t soc_clk_sel = REG_GET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_SOC_CLK_SEL);
switch (soc_clk_sel) {
case RTC_CNTL_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 RTC_CNTL_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 RTC_CNTL_SOC_CLK_SEL_APLL:
case RTC_CNTL_SOC_CLK_SEL_8M:
default:
assert(false && "unsupported frequency");
}
return RTC_CNTL_SOC_CLK_SEL_XTL;
rtc_cpu_freq_config_t config;
rtc_clk_cpu_freq_get_config(&config);
rtc_cpu_freq_t freq;
rtc_clk_cpu_freq_from_mhz_internal(config.freq_mhz, &freq);
return freq;
}
uint32_t rtc_clk_cpu_freq_value(rtc_cpu_freq_t cpu_freq)
@@ -564,7 +500,7 @@ uint32_t rtc_clk_cpu_freq_value(rtc_cpu_freq_t cpu_freq)
}
}
bool rtc_clk_cpu_freq_from_mhz(int mhz, rtc_cpu_freq_t* out_val)
static bool rtc_clk_cpu_freq_from_mhz_internal(int mhz, rtc_cpu_freq_t* out_val)
{
if (mhz == 240) {
*out_val = RTC_CPU_FREQ_240M;
@@ -582,22 +518,197 @@ bool rtc_clk_cpu_freq_from_mhz(int mhz, rtc_cpu_freq_t* out_val)
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;
bool rtc_clk_cpu_freq_from_mhz(int mhz, rtc_cpu_freq_t* out_val)
{
return rtc_clk_cpu_freq_from_mhz_internal(mhz, out_val);
}
static uint32_t reg_val_to_clk_val(uint32_t val) {
return val & UINT16_MAX;
void rtc_clk_cpu_freq_to_config(rtc_cpu_freq_t cpu_freq, rtc_cpu_freq_config_t* out_config)
{
uint32_t source_freq_mhz;
rtc_cpu_freq_src_t source;
uint32_t freq_mhz;
uint32_t divider;
switch (cpu_freq) {
case RTC_CPU_FREQ_XTAL:
case RTC_CPU_FREQ_2M:
source_freq_mhz = rtc_clk_xtal_freq_get();
source = RTC_CPU_FREQ_SRC_XTAL;
if (cpu_freq == RTC_CPU_FREQ_2M) {
freq_mhz = 2;
divider = out_config->source_freq_mhz / 2;
} else {
freq_mhz = source_freq_mhz;
divider = 1;
}
break;
case RTC_CPU_FREQ_80M:
source = RTC_CPU_FREQ_SRC_PLL;
source_freq_mhz = RTC_PLL_FREQ_320M;
divider = 4;
freq_mhz = 80;
break;
case RTC_CPU_FREQ_160M:
source = RTC_CPU_FREQ_SRC_PLL;
source_freq_mhz = RTC_PLL_FREQ_320M;
divider = 2;
freq_mhz = 160;
break;
case RTC_CPU_FREQ_240M:
source = RTC_CPU_FREQ_SRC_PLL;
source_freq_mhz = RTC_PLL_FREQ_480M;
divider = 2;
freq_mhz = 240;
break;
default:
assert(false && "invalid rtc_cpu_freq_t value");
abort();
}
*out_config = (rtc_cpu_freq_config_t) {
.source = source,
.source_freq_mhz = source_freq_mhz,
.div = divider,
.freq_mhz = freq_mhz
};
}
static uint32_t clk_val_to_reg_val(uint32_t val) {
return (val & UINT16_MAX) | ((val & UINT16_MAX) << 16);
bool rtc_clk_cpu_freq_mhz_to_config(uint32_t freq_mhz, rtc_cpu_freq_config_t* out_config)
{
uint32_t source_freq_mhz;
rtc_cpu_freq_src_t source;
uint32_t divider;
uint32_t real_freq_mhz;
uint32_t xtal_freq = (uint32_t) rtc_clk_xtal_freq_get();
if (freq_mhz <= xtal_freq) {
divider = xtal_freq / freq_mhz;
real_freq_mhz = (xtal_freq + divider / 2) / divider; /* round */
if (real_freq_mhz != freq_mhz) {
// no suitable divider
return false;
}
source_freq_mhz = xtal_freq;
source = RTC_CPU_FREQ_SRC_XTAL;
} else if (freq_mhz == 80) {
real_freq_mhz = freq_mhz;
source = RTC_CPU_FREQ_SRC_PLL;
source_freq_mhz = RTC_PLL_FREQ_320M;
divider = 4;
} else if (freq_mhz == 160) {
real_freq_mhz = freq_mhz;
source = RTC_CPU_FREQ_SRC_PLL;
source_freq_mhz = RTC_PLL_FREQ_320M;
divider = 2;
} else if (freq_mhz == 240) {
real_freq_mhz = freq_mhz;
source = RTC_CPU_FREQ_SRC_PLL;
source_freq_mhz = RTC_PLL_FREQ_480M;
divider = 2;
} else {
// unsupported frequency
return false;
}
*out_config = (rtc_cpu_freq_config_t) {
.source = source,
.div = divider,
.source_freq_mhz = source_freq_mhz,
.freq_mhz = real_freq_mhz
};
return true;
}
void rtc_clk_cpu_freq_set_config(const rtc_cpu_freq_config_t* config)
{
rtc_xtal_freq_t xtal_freq = rtc_clk_xtal_freq_get();
uint32_t soc_clk_sel = REG_GET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_SOC_CLK_SEL);
if (soc_clk_sel != RTC_CNTL_SOC_CLK_SEL_XTL) {
rtc_clk_cpu_freq_to_xtal(xtal_freq, 1);
rtc_clk_wait_for_slow_cycle();
}
if (soc_clk_sel == RTC_CNTL_SOC_CLK_SEL_PLL) {
rtc_clk_bbpll_disable();
}
if (config->source == RTC_CPU_FREQ_SRC_XTAL) {
if (config->div > 1) {
rtc_clk_cpu_freq_to_xtal(config->freq_mhz, config->div);
}
} else if (config->source == RTC_CPU_FREQ_SRC_PLL) {
rtc_clk_bbpll_enable();
rtc_clk_wait_for_slow_cycle();
rtc_clk_bbpll_configure(rtc_clk_xtal_freq_get(), config->source_freq_mhz);
rtc_clk_cpu_freq_to_pll_mhz(config->freq_mhz);
} else if (config->source == RTC_CPU_FREQ_SRC_8M) {
rtc_clk_cpu_freq_to_8m();
}
}
void rtc_clk_cpu_freq_get_config(rtc_cpu_freq_config_t* out_config)
{
rtc_cpu_freq_src_t source;
uint32_t source_freq_mhz;
uint32_t div;
uint32_t freq_mhz;
uint32_t soc_clk_sel = REG_GET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_SOC_CLK_SEL);
switch (soc_clk_sel) {
case RTC_CNTL_SOC_CLK_SEL_XTL: {
source = RTC_CPU_FREQ_SRC_XTAL;
div = REG_GET_FIELD(APB_CTRL_SYSCLK_CONF_REG, APB_CTRL_PRE_DIV_CNT) + 1;
source_freq_mhz = (uint32_t) rtc_clk_xtal_freq_get();
freq_mhz = source_freq_mhz / div;
}
break;
case RTC_CNTL_SOC_CLK_SEL_PLL: {
source = RTC_CPU_FREQ_SRC_PLL;
uint32_t cpuperiod_sel = DPORT_REG_GET_FIELD(DPORT_CPU_PER_CONF_REG, DPORT_CPUPERIOD_SEL);
if (cpuperiod_sel == 0) {
source_freq_mhz = RTC_PLL_FREQ_320M;
div = 4;
freq_mhz = 80;
} else if (cpuperiod_sel == 1) {
source_freq_mhz = RTC_PLL_FREQ_320M;
div = 2;
freq_mhz = 160;
} else if (cpuperiod_sel == 2) {
source_freq_mhz = RTC_PLL_FREQ_480M;
div = 2;
freq_mhz = 240;
} else {
assert(false && "unsupported frequency configuration");
}
break;
}
case RTC_CNTL_SOC_CLK_SEL_8M:
source = RTC_CPU_FREQ_SRC_8M;
source_freq_mhz = 8;
div = 1;
freq_mhz = source_freq_mhz;
break;
case RTC_CNTL_SOC_CLK_SEL_APLL:
default:
assert(false && "unsupported frequency configuration");
}
*out_config = (rtc_cpu_freq_config_t) {
.source = source,
.source_freq_mhz = source_freq_mhz,
.div = div,
.freq_mhz = freq_mhz
};
}
void rtc_clk_cpu_freq_set_config_fast(const rtc_cpu_freq_config_t* config)
{
if (config->source == RTC_CPU_FREQ_SRC_XTAL) {
rtc_clk_cpu_freq_to_xtal(config->freq_mhz, config->div);
} else if (config->source == RTC_CPU_FREQ_SRC_PLL &&
s_cur_pll_freq == config->source_freq_mhz) {
rtc_clk_cpu_freq_to_pll_mhz(config->freq_mhz);
} else {
/* fallback */
rtc_clk_cpu_freq_set_config(config);
}
}
rtc_xtal_freq_t rtc_clk_xtal_freq_get()
@@ -605,7 +716,6 @@ rtc_xtal_freq_t rtc_clk_xtal_freq_get()
/* 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_AUTO;
}
return reg_val_to_clk_val(xtal_freq_reg);
@@ -616,42 +726,6 @@ 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()
{
/* 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));
@@ -666,90 +740,6 @@ uint32_t rtc_clk_apb_freq_get()
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 RTC_CNTL_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, RTC_CNTL_SOC_CLK_SEL) == RTC_CNTL_SOC_CLK_SEL_PLL) {
rtc_clk_cpu_freq_set(RTC_CPU_FREQ_XTAL);
}
/* 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);
/* Estimate XTAL frequency */
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
*/

38
components/soc/esp32/rtc_clk_common.h Normal file
View File

@@ -0,0 +1,38 @@
// Copyright 2015-2018 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.
#pragma once
#define MHZ (1000000)
void rtc_clk_cpu_freq_to_xtal(int freq, int div);
/* 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 inline bool clk_val_is_valid(uint32_t val) {
return (val & 0xffff) == ((val >> 16) & 0xffff) &&
val != 0 &&
val != UINT32_MAX;
}
static inline uint32_t reg_val_to_clk_val(uint32_t val) {
return val & UINT16_MAX;
}
static inline uint32_t clk_val_to_reg_val(uint32_t val) {
return (val & UINT16_MAX) | ((val & UINT16_MAX) << 16);
}

176
components/soc/esp32/rtc_clk_init.c Normal file
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@@ -0,0 +1,176 @@
// Copyright 2015-2018 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 <stdbool.h>
#include <stdint.h>
#include <stddef.h>
#include <assert.h>
#include <stdlib.h>
#include "rom/ets_sys.h"
#include "rom/rtc.h"
#include "rom/uart.h"
#include "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 "sdkconfig.h"
#include "xtensa/core-macros.h"
#include "rtc_clk_common.h"
/* 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
static rtc_xtal_freq_t rtc_clk_xtal_freq_estimate();
static const char* TAG = "rtc_clk_init";
void rtc_clk_init(rtc_clk_config_t cfg)
{
rtc_cpu_freq_config_t old_config, new_config;
/* 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 RTC_CNTL_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, RTC_CNTL_SOC_CLK_SEL) == RTC_CNTL_SOC_CLK_SEL_PLL) {
/* We don't know actual XTAL frequency yet, assume 40MHz.
* REF_TICK divider will be corrected below, once XTAL frequency is
* determined.
*/
rtc_clk_cpu_freq_to_xtal(40, 1);
}
/* 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);
/* Estimate XTAL frequency */
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_get_config(&old_config);
uint32_t freq_before = old_config.freq_mhz;
bool res = rtc_clk_cpu_freq_mhz_to_config(cfg.cpu_freq_mhz, &new_config);
assert(res && "invalid CPU frequency value");
/* Configure REF_TICK */
REG_WRITE(APB_CTRL_XTAL_TICK_CONF_REG, xtal_freq - 1);
REG_WRITE(APB_CTRL_PLL_TICK_CONF_REG, APB_CLK_FREQ / MHZ - 1); /* Under PLL, APB frequency is always 80MHz */
/* Re-calculate the ccount to make time calculation correct. */
XTHAL_SET_CCOUNT( XTHAL_GET_CCOUNT() * cfg.cpu_freq_mhz / 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);
}
static rtc_xtal_freq_t rtc_clk_xtal_freq_estimate()
{
/* 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);
}

17
components/soc/esp32/test/test_rtc_clk.c
View File

@@ -95,7 +95,7 @@ TEST_CASE("Output 8M XTAL clock to GPIO25", "[rtc_clk][ignore]")
pull_out_clk(RTC_IO_DEBUG_SEL0_8M);
}
static void test_clock_switching(void (*switch_func)(rtc_cpu_freq_t))
static void test_clock_switching(void (*switch_func)(const rtc_cpu_freq_config_t* config))
{
uart_tx_wait_idle(CONFIG_CONSOLE_UART_NUM);
@@ -103,11 +103,16 @@ static void test_clock_switching(void (*switch_func)(rtc_cpu_freq_t))
ref_clock_init();
uint64_t t_start = ref_clock_get();
rtc_cpu_freq_t cur_freq = rtc_clk_cpu_freq_get();
rtc_cpu_freq_config_t cur_config;
rtc_clk_cpu_freq_get_config(&cur_config);
rtc_cpu_freq_config_t xtal_config;
rtc_clk_cpu_freq_mhz_to_config((uint32_t) rtc_clk_xtal_freq_get(), &xtal_config);
int count = 0;
while (ref_clock_get() - t_start < test_duration_sec * 1000000) {
switch_func(RTC_CPU_FREQ_XTAL);
switch_func(cur_freq);
switch_func(&xtal_config);
switch_func(&cur_config);
++count;
}
uint64_t t_end = ref_clock_get();
@@ -126,12 +131,12 @@ TEST_CASE("Calculate 8M clock frequency", "[rtc_clk]")
TEST_CASE("Test switching between PLL and XTAL", "[rtc_clk]")
{
test_clock_switching(rtc_clk_cpu_freq_set);
test_clock_switching(rtc_clk_cpu_freq_set_config);
}
TEST_CASE("Test fast switching between PLL and XTAL", "[rtc_clk]")
{
test_clock_switching(rtc_clk_cpu_freq_set_fast);
test_clock_switching(rtc_clk_cpu_freq_set_config_fast);
}
#define COUNT_TEST 3