newlib: use RTC_STORE registers to keep boot time instead of RTC_SLOW_MEM

This allows RTC_SLOW_MEM to be powered down in deep sleep if no other variables are placed into RTC_SLOW_MEM.
This commit is contained in:
Ivan Grokhotkov 2017-01-11 17:28:09 +08:00
parent 9aa0e29079
commit b24ac487cb
3 changed files with 41 additions and 19 deletions

View file

@ -381,6 +381,8 @@ choice ESP32_TIME_SYSCALL
longer to run.
- If no timers are used, gettimeofday and time functions
return -1 and set errno to ENOSYS.
- When RTC is used for timekeeping, two RTC_STORE registers are
used to keep time in deep sleep mode.
config ESP32_TIME_SYSCALL_USE_RTC
bool "RTC"

View file

@ -53,16 +53,18 @@ extern "C" {
* Rtc store registers usage
* RTC_CNTL_STORE0_REG
* RTC_CNTL_STORE1_REG
* RTC_CNTL_STORE2_REG
* RTC_CNTL_STORE3_REG
* RTC_CNTL_STORE4_REG Reserved
* RTC_CNTL_STORE5_REG External Xtal Frequency
* RTC_CNTL_STORE2_REG Boot time, low word
* RTC_CNTL_STORE3_REG Boot time, high word
* RTC_CNTL_STORE4_REG External XTAL frequency
* RTC_CNTL_STORE5_REG APB bus frequency
* RTC_CNTL_STORE6_REG FAST_RTC_MEMORY_ENTRY
* RTC_CNTL_STORE7_REG FAST_RTC_MEMORY_CRC
*************************************************************************************
*/
#define RTC_ENTRY_ADDR_REG RTC_CNTL_STORE6_REG
#define RTC_MEMORY_CRC_REG RTC_CNTL_STORE7_REG
#define RTC_BOOT_TIME_LOW_REG RTC_CNTL_STORE2_REG
#define RTC_BOOT_TIME_HIGH_REG RTC_CNTL_STORE3_REG
#define RTC_ENTRY_ADDR_REG RTC_CNTL_STORE6_REG
#define RTC_MEMORY_CRC_REG RTC_CNTL_STORE7_REG
typedef enum {

View file

@ -21,6 +21,7 @@
#include <sys/time.h>
#include <sys/times.h>
#include <sys/lock.h>
#include <rom/rtc.h>
#include "esp_attr.h"
#include "esp_intr_alloc.h"
#include "soc/soc.h"
@ -58,9 +59,9 @@ static uint64_t get_rtc_time_us()
// s_boot_time: time from Epoch to the first boot time
#ifdef WITH_RTC
static RTC_DATA_ATTR struct timeval s_boot_time;
// when RTC is used to persist time, two RTC_STORE registers are used to store boot time
#elif defined(WITH_FRC1)
static struct timeval s_boot_time;
static uint64_t s_boot_time;
#endif
#if defined(WITH_RTC) || defined(WITH_FRC1)
@ -88,6 +89,31 @@ static void IRAM_ATTR frc_timer_isr()
#endif // WITH_FRC1
static void set_boot_time(uint64_t time_us)
{
_lock_acquire(&s_boot_time_lock);
#ifdef WITH_RTC
REG_WRITE(RTC_BOOT_TIME_LOW_REG, (uint32_t) (time_us & 0xffffffff));
REG_WRITE(RTC_BOOT_TIME_HIGH_REG, (uint32_t) (time_us >> 32));
#else
s_boot_time = time_us;
#endif
_lock_release(&s_boot_time_lock);
}
static uint64_t get_boot_time()
{
uint64_t result;
_lock_acquire(&s_boot_time_lock);
#ifdef WITH_RTC
result = ((uint64_t) REG_READ(RTC_BOOT_TIME_LOW_REG)) + (((uint64_t) REG_READ(RTC_BOOT_TIME_HIGH_REG)) << 32);
#else
result = s_boot_time;
#endif
_lock_release(&s_boot_time_lock);
return result;
}
void esp_setup_time_syscalls()
{
#if defined( WITH_FRC1 )
@ -148,13 +174,10 @@ int IRAM_ATTR _gettimeofday_r(struct _reent *r, struct timeval *tv, void *tz)
{
(void) tz;
#if defined( WITH_FRC1 ) || defined( WITH_RTC )
uint64_t microseconds = get_time_since_boot();
if (tv) {
_lock_acquire(&s_boot_time_lock);
microseconds += s_boot_time.tv_usec;
tv->tv_sec = s_boot_time.tv_sec + microseconds / 1000000;
uint64_t microseconds = get_boot_time() + get_time_since_boot();
tv->tv_sec = microseconds / 1000000;
tv->tv_usec = microseconds % 1000000;
_lock_release(&s_boot_time_lock);
}
return 0;
#else
@ -168,14 +191,9 @@ int settimeofday(const struct timeval *tv, const struct timezone *tz)
(void) tz;
#if defined( WITH_FRC1 ) || defined( WITH_RTC )
if (tv) {
_lock_acquire(&s_boot_time_lock);
uint64_t now = ((uint64_t) tv->tv_sec) * 1000000LL + tv->tv_usec;
uint64_t since_boot = get_time_since_boot();
uint64_t boot_time = now - since_boot;
s_boot_time.tv_sec = boot_time / 1000000;
s_boot_time.tv_usec = boot_time % 1000000;
_lock_release(&s_boot_time_lock);
set_boot_time(now - since_boot);
}
return 0;
#else