static int cc32xx_uart_rx_bytes(uint32_t base, struct cs_rbuf *rxb) {
int num_recd = 0;
while (rxb->avail > 0 && MAP_UARTCharsAvail(base)) {
uint32_t chf = HWREG(base + UART_O_DR);
/* Note: There are error flags here, we may be interested in those. */
cs_rbuf_append_one(rxb, (uint8_t) chf);
num_recd++;
}
return num_recd;
}
IRAM int esp_uart_dispatch_rx_top(int uart_no) {
struct esp_uart_state *us = s_us[uart_no];
if (us == NULL || !us->rx_enabled) return 1;
uint32_t rxn = 0;
cs_rbuf_t *rxb = &us->rx_buf;
/* RX */
if (rxb->avail > 0 && rx_fifo_len(uart_no) > 0) {
int linger_counter = 0;
/* 32 here is a constant measured (using system_get_time) to provide
* linger time of rx_linger_micros. It basically means that one iteration
* of the loop takes 3.2 us.
*
* Note: lingering may starve TX FIFO if the flow is bidirectional.
* TODO(rojer): keep transmitting from tx_buf while lingering.
*/
int max_linger = us->cfg->rx_linger_micros / 10 * 32;
#ifdef MEASURE_LINGER_TIME
uint32_t st = system_get_time();
#endif
while (rxb->avail > 0 && linger_counter <= max_linger) {
int rx_len = rx_fifo_len(uart_no);
if (rx_len > 0) {
while (rx_len-- > 0 && rxb->avail > 0) {
cs_rbuf_append_one(rxb, rx_byte(uart_no));
rxn++;
}
if (linger_counter > 0) {
us->stats.rx_linger_conts++;
linger_counter = 0;
}
} else {
linger_counter++;
}
}
#ifdef MEASURE_LINGER_TIME
fprintf(stderr, "Time spent reading: %u us\n", system_get_time() - st);
#endif
us->stats.rx_bytes += rxn;
}
int rfl = rx_fifo_len(uart_no);
if (rfl < us->cfg->rx_fifo_full_thresh) {
CLEAR_PERI_REG_MASK(UART_INT_CLR(uart_no), UART_RX_INTS);
}
return rfl == 0;
}