From eea38d76986f366d07fa781d19e28e7fda5d4ca8 Mon Sep 17 00:00:00 2001 From: xiongyu Date: Fri, 29 May 2020 22:09:36 +0800 Subject: [PATCH] bugfix(uart): fix esp32 fifo_cnt bug When using DPort to read fifo, fifo_cnt is not credible, we need to calculate the real cnt based on the fifo read and write pointer. When using AHB to read FIFO, we can use fifo_cnt to indicate the data length in fifo. --- components/soc/src/esp32/include/hal/uart_ll.h | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/components/soc/src/esp32/include/hal/uart_ll.h b/components/soc/src/esp32/include/hal/uart_ll.h index dc4a05bffe..2be4adbe66 100644 --- a/components/soc/src/esp32/include/hal/uart_ll.h +++ b/components/soc/src/esp32/include/hal/uart_ll.h @@ -238,7 +238,21 @@ static inline void uart_ll_txfifo_rst(uart_dev_t *hw) */ static inline uint32_t uart_ll_get_rxfifo_len(uart_dev_t *hw) { - return hw->status.rxfifo_cnt; + uint32_t fifo_cnt = hw->status.rxfifo_cnt; + typeof(hw->mem_rx_status) rx_status = hw->mem_rx_status; + uint32_t len = 0; + + // When using DPort to read fifo, fifo_cnt is not credible, we need to calculate the real cnt based on the fifo read and write pointer. + // When using AHB to read FIFO, we can use fifo_cnt to indicate the data length in fifo. + if (rx_status.wr_addr > rx_status.rd_addr) { + len = rx_status.wr_addr - rx_status.rd_addr; + } else if (rx_status.wr_addr < rx_status.rd_addr) { + len = (rx_status.wr_addr + 128) - rx_status.rd_addr; + } else { + len = fifo_cnt > 0 ? 128 : 0; + } + + return len; } /**