Commit 209cb815 authored by Raymond Lei's avatar Raymond Lei Committed by Mahesh Mahadevan
Browse files

drivers: serial: lpuart: Enable SG mode of LPUART 



New implemented eDMA loop SG mode can be used to lpuart driver to fix
the conflict of "Done" bit issue which cause uart_async_api test failed
when SG mode is enabled.

Also, this loop SG mode works well even with a high bandrate(test done
on 2000000bps).
Fixes: #78291

Signed-off-by: default avatarRaymond Lei <raymond.lei@nxp.com>
parent 7145295a

drivers/serial/uart_mcux_lpuart.c

+15 −23
Original line number Diff line number Diff line
@@ -585,7 +585,7 @@ static void prepare_rx_dma_block_config(const struct device *dev) 
	head_block_config->dest_address = (uint32_t)rx_dma_params->buf;

	head_block_config->source_address = LPUART_GetDataRegisterAddress(lpuart);

	head_block_config->block_size = rx_dma_params->buf_len;

	head_block_config->dest_scatter_en = false;

	head_block_config->dest_scatter_en = true;

}



static int configure_and_start_rx_dma(
@@ -616,37 +616,20 @@ static int uart_mcux_lpuart_dma_replace_rx_buffer(const struct device *dev) 
	struct mcux_lpuart_data *data = (struct mcux_lpuart_data *)dev->data;

	const struct mcux_lpuart_config *config = dev->config;

	LPUART_Type *lpuart = config->base;

	struct mcux_lpuart_rx_dma_params *rx_dma_params = &data->async.rx_dma_params;



	LOG_DBG("Replacing RX buffer, new length: %d", data->async.next_rx_buffer_len);



	/* There must be a buffer to replace this one with */

	assert(data->async.next_rx_buffer != NULL);

	assert(data->async.next_rx_buffer_len != 0U);

	rx_dma_params->buf = data->async.next_rx_buffer;

	rx_dma_params->buf_len = data->async.next_rx_buffer_len;

	rx_dma_params->offset = 0;

	rx_dma_params->counter = 0;

	data->async.next_rx_buffer = NULL;

	data->async.next_rx_buffer_len = 0U;



	const int success =

		dma_reload(config->rx_dma_config.dma_dev, config->rx_dma_config.dma_channel,

			   LPUART_GetDataRegisterAddress(lpuart), (uint32_t)rx_dma_params->buf,

			   rx_dma_params->buf_len);

			   LPUART_GetDataRegisterAddress(lpuart),

			   (uint32_t)data->async.next_rx_buffer, data->async.next_rx_buffer_len);



	if (success != 0) {

		LOG_ERR("Error %d reloading DMA with next RX buffer", success);

	}

	/* Request next buffer */

	async_evt_rx_buf_request(dev);



	int ret = dma_start(config->rx_dma_config.dma_dev, config->rx_dma_config.dma_channel);



	if (ret < 0) {

		LOG_ERR("Failed to start DMA(Rx) Ch %d(%d)", config->rx_dma_config.dma_channel,

			ret);

	}



	return success;

}
@@ -692,9 +675,16 @@ static void dma_callback(const struct device *dma_dev, void *callback_arg, uint3 
		async_evt_rx_rdy(dev);

		async_evt_rx_buf_release(dev);



		if (data->async.next_rx_buffer != NULL && data->async.next_rx_buffer_len > 0) {

		/* Remember the buf so it can be released after it is done. */

		rx_dma_params->buf = data->async.next_rx_buffer;

		rx_dma_params->buf_len = data->async.next_rx_buffer_len;

		data->async.next_rx_buffer = NULL;

		data->async.next_rx_buffer_len = 0U;



		/* A new buffer was available (and already loaded into the DMA engine) */

		if (rx_dma_params->buf != NULL && rx_dma_params->buf_len > 0) {

			/* Request the next buffer */

			uart_mcux_lpuart_dma_replace_rx_buffer(dev);

			async_evt_rx_buf_request(dev);

		} else {

			/* Buffer full without valid next buffer, disable RX DMA */

			LOG_INF("Disabled RX DMA, no valid next buffer ");
@@ -873,6 +863,7 @@ static int mcux_lpuart_rx_buf_rsp(const struct device *dev, uint8_t *buf, size_t 
	assert(data->async.next_rx_buffer_len == 0);

	data->async.next_rx_buffer = buf;

	data->async.next_rx_buffer_len = len;

	uart_mcux_lpuart_dma_replace_rx_buffer(dev);

	irq_unlock(key);

	return 0;

}
@@ -1347,7 +1338,8 @@ static const struct uart_driver_api mcux_lpuart_driver_api = { 
			.dma_slot = DT_INST_DMAS_CELL_BY_NAME(				       \

				id, rx, source),					       \

			.dma_callback = dma_callback,					       \

			.user_data = (void *)DEVICE_DT_INST_GET(id)			       \

			.user_data = (void *)DEVICE_DT_INST_GET(id),			       \

			.cyclic = 1,							       \

		},									       \

	},

#else

CRA Git | Maintained and supported by SUSTech CRA and CCSE