esp32s2: suspend UART output using XOFF before entering light sleep

Same logic as for the ESP32, except two changes:

* need to set UART_SW_FLOW_CON_EN bit for UART_FORCE_XOFF to take
  effect
* need to check if the peripheral is not clockgated and out of reset
This commit is contained in:
Ivan Grokhotkov 2020-04-28 19:40:12 +02:00
parent 1f8c5b2b64
commit 31cd3f1294

View file

@ -34,6 +34,7 @@
#include "soc/soc_memory_layout.h"
#include "soc/uart_caps.h"
#include "hal/wdt_hal.h"
#include "hal/clk_gate_ll.h"
#include "driver/rtc_io.h"
#include "driver/uart.h"
#include "freertos/FreeRTOS.h"
@ -144,21 +145,34 @@ void esp_deep_sleep(uint64_t time_in_us)
static void IRAM_ATTR flush_uarts(void)
{
for (int i = 0; i < SOC_UART_NUM; ++i) {
uart_tx_wait_idle(i);
if (periph_ll_periph_enabled(PERIPH_UART0_MODULE + i)) {
uart_tx_wait_idle(i);
}
}
}
static void IRAM_ATTR suspend_uarts(void)
{
for (int i = 0; i < SOC_UART_NUM; ++i) {
uart_tx_wait_idle(i);
/* Note: Set `UART_FORCE_XOFF` can't stop new Tx request. */
if (periph_ll_periph_enabled(PERIPH_UART0_MODULE + i)) {
REG_CLR_BIT(UART_FLOW_CONF_REG(i), UART_FORCE_XON);
REG_SET_BIT(UART_FLOW_CONF_REG(i), UART_SW_FLOW_CON_EN | UART_FORCE_XOFF);
while (REG_GET_FIELD(UART_FSM_STATUS_REG(i), UART_ST_UTX_OUT) != 0) {
;
}
}
}
}
static void IRAM_ATTR resume_uarts(void)
{
/* Note: Set `UART_FORCE_XOFF` can't stop new Tx request. */
for (int i = 0; i < SOC_UART_NUM; ++i) {
if (periph_ll_periph_enabled(PERIPH_UART0_MODULE + 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_SW_FLOW_CON_EN | UART_FORCE_XON);
}
}
}
static uint32_t IRAM_ATTR esp_sleep_start(uint32_t pd_flags)