[PATCH v2 3/4] serial: 8250-mtk: add uart DMA support
Modify uart register to support DMA function. Signed-off-by: Long Cheng --- drivers/tty/serial/8250/8250_mtk.c | 210 +++- 1 file changed, 209 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c index dd5e1ce..1da73e8 100644 --- a/drivers/tty/serial/8250/8250_mtk.c +++ b/drivers/tty/serial/8250/8250_mtk.c @@ -14,6 +14,10 @@ #include #include #include +#include +#include +#include +#include #include "8250.h" @@ -22,12 +26,172 @@ #define UART_MTK_SAMPLE_POINT 0x0b/* Sample point register */ #define MTK_UART_RATE_FIX 0x0d/* UART Rate Fix Register */ +#define MTK_UART_DMA_EN0x13/* DMA Enable register */ +#define MTK_UART_DMA_EN_TX 0x2 +#define MTK_UART_DMA_EN_RX 0x5 + +#define MTK_UART_TX_SIZE UART_XMIT_SIZE +#define MTK_UART_RX_SIZE 0x8000 +#define MTK_UART_TX_TRIGGER1 +#define MTK_UART_RX_TRIGGERMTK_UART_RX_SIZE + +#ifdef CONFIG_SERIAL_8250_DMA +enum dma_rx_status { + DMA_RX_START = 0, + DMA_RX_RUNNING = 1, + DMA_RX_SHUTDOWN = 2, +}; +#endif + struct mtk8250_data { int line; + unsigned intrx_pos; struct clk *uart_clk; struct clk *bus_clk; + struct uart_8250_dma*dma; +#ifdef CONFIG_SERIAL_8250_DMA + enum dma_rx_status rx_status; +#endif }; +#ifdef CONFIG_SERIAL_8250_DMA +static void mtk8250_rx_dma(struct uart_8250_port *up); + +static void mtk8250_dma_rx_complete(void *param) +{ + struct uart_8250_port *up = param; + struct uart_8250_dma *dma = up->dma; + struct mtk8250_data *data = up->port.private_data; + struct tty_port *tty_port = >port.state->port; + struct dma_tx_state state; + unsigned char *ptr; + int copied; + + dma_sync_single_for_cpu(dma->rxchan->device->dev, dma->rx_addr, + dma->rx_size, DMA_FROM_DEVICE); + + dmaengine_tx_status(dma->rxchan, dma->rx_cookie, ); + + if (data->rx_status == DMA_RX_SHUTDOWN) + return; + + if ((data->rx_pos + state.residue) <= dma->rx_size) { + ptr = (unsigned char *)(data->rx_pos + dma->rx_buf); + copied = tty_insert_flip_string(tty_port, ptr, state.residue); + } else { + ptr = (unsigned char *)(data->rx_pos + dma->rx_buf); + copied = tty_insert_flip_string(tty_port, ptr, + dma->rx_size - data->rx_pos); + ptr = (unsigned char *)(dma->rx_buf); + copied += tty_insert_flip_string(tty_port, ptr, + data->rx_pos + state.residue - dma->rx_size); + } + up->port.icount.rx += copied; + + tty_flip_buffer_push(tty_port); + + mtk8250_rx_dma(up); +} + +static void mtk8250_rx_dma(struct uart_8250_port *up) +{ + struct uart_8250_dma *dma = up->dma; + struct mtk8250_data *data = up->port.private_data; + struct dma_async_tx_descriptor *desc; + struct dma_tx_state state; + + desc = dmaengine_prep_slave_single(dma->rxchan, dma->rx_addr, + dma->rx_size, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc) { + pr_err("failed to prepare rx slave single\n"); + return; + } + + desc->callback = mtk8250_dma_rx_complete; + desc->callback_param = up; + + dma->rx_cookie = dmaengine_submit(desc); + + dmaengine_tx_status(dma->rxchan, dma->rx_cookie, ); + data->rx_pos = state.residue; + + dma_sync_single_for_device(dma->rxchan->device->dev, dma->rx_addr, + dma->rx_size, DMA_FROM_DEVICE); + + dma_async_issue_pending(dma->rxchan); +} + +static void mtk8250_dma_enable(struct uart_8250_port *up) +{ + struct uart_8250_dma *dma = up->dma; + struct mtk8250_data *data = up->port.private_data; + int lcr = serial_in(up, UART_LCR); + + if (data->rx_status != DMA_RX_START) + return; + + dma->rxconf.direction = DMA_DEV_TO_MEM; + dma->rxconf.src_addr_width = dma->rx_size / 1024; + dma->rxconf.src_addr= dma->rx_addr; + + dma->txconf.direction = DMA_MEM_TO_DEV; + dma->txconf.dst_addr_width = MTK_UART_TX_SIZE / 1024; + dma->txconf.dst_addr= dma->tx_addr; + + serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | + UART_FCR_CLEAR_XMIT); + serial_out(up, MTK_UART_DMA_EN, + MTK_UART_DMA_EN_RX | MTK_UART_DMA_EN_TX); + + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + serial_out(up, UART_EFR, UART_EFR_ECB); + serial_out(up, UART_LCR, lcr); + + if
[PATCH v2 3/4] serial: 8250-mtk: add uart DMA support
Modify uart register to support DMA function. Signed-off-by: Long Cheng --- drivers/tty/serial/8250/8250_mtk.c | 210 +++- 1 file changed, 209 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c index dd5e1ce..1da73e8 100644 --- a/drivers/tty/serial/8250/8250_mtk.c +++ b/drivers/tty/serial/8250/8250_mtk.c @@ -14,6 +14,10 @@ #include #include #include +#include +#include +#include +#include #include "8250.h" @@ -22,12 +26,172 @@ #define UART_MTK_SAMPLE_POINT 0x0b/* Sample point register */ #define MTK_UART_RATE_FIX 0x0d/* UART Rate Fix Register */ +#define MTK_UART_DMA_EN0x13/* DMA Enable register */ +#define MTK_UART_DMA_EN_TX 0x2 +#define MTK_UART_DMA_EN_RX 0x5 + +#define MTK_UART_TX_SIZE UART_XMIT_SIZE +#define MTK_UART_RX_SIZE 0x8000 +#define MTK_UART_TX_TRIGGER1 +#define MTK_UART_RX_TRIGGERMTK_UART_RX_SIZE + +#ifdef CONFIG_SERIAL_8250_DMA +enum dma_rx_status { + DMA_RX_START = 0, + DMA_RX_RUNNING = 1, + DMA_RX_SHUTDOWN = 2, +}; +#endif + struct mtk8250_data { int line; + unsigned intrx_pos; struct clk *uart_clk; struct clk *bus_clk; + struct uart_8250_dma*dma; +#ifdef CONFIG_SERIAL_8250_DMA + enum dma_rx_status rx_status; +#endif }; +#ifdef CONFIG_SERIAL_8250_DMA +static void mtk8250_rx_dma(struct uart_8250_port *up); + +static void mtk8250_dma_rx_complete(void *param) +{ + struct uart_8250_port *up = param; + struct uart_8250_dma *dma = up->dma; + struct mtk8250_data *data = up->port.private_data; + struct tty_port *tty_port = >port.state->port; + struct dma_tx_state state; + unsigned char *ptr; + int copied; + + dma_sync_single_for_cpu(dma->rxchan->device->dev, dma->rx_addr, + dma->rx_size, DMA_FROM_DEVICE); + + dmaengine_tx_status(dma->rxchan, dma->rx_cookie, ); + + if (data->rx_status == DMA_RX_SHUTDOWN) + return; + + if ((data->rx_pos + state.residue) <= dma->rx_size) { + ptr = (unsigned char *)(data->rx_pos + dma->rx_buf); + copied = tty_insert_flip_string(tty_port, ptr, state.residue); + } else { + ptr = (unsigned char *)(data->rx_pos + dma->rx_buf); + copied = tty_insert_flip_string(tty_port, ptr, + dma->rx_size - data->rx_pos); + ptr = (unsigned char *)(dma->rx_buf); + copied += tty_insert_flip_string(tty_port, ptr, + data->rx_pos + state.residue - dma->rx_size); + } + up->port.icount.rx += copied; + + tty_flip_buffer_push(tty_port); + + mtk8250_rx_dma(up); +} + +static void mtk8250_rx_dma(struct uart_8250_port *up) +{ + struct uart_8250_dma *dma = up->dma; + struct mtk8250_data *data = up->port.private_data; + struct dma_async_tx_descriptor *desc; + struct dma_tx_state state; + + desc = dmaengine_prep_slave_single(dma->rxchan, dma->rx_addr, + dma->rx_size, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc) { + pr_err("failed to prepare rx slave single\n"); + return; + } + + desc->callback = mtk8250_dma_rx_complete; + desc->callback_param = up; + + dma->rx_cookie = dmaengine_submit(desc); + + dmaengine_tx_status(dma->rxchan, dma->rx_cookie, ); + data->rx_pos = state.residue; + + dma_sync_single_for_device(dma->rxchan->device->dev, dma->rx_addr, + dma->rx_size, DMA_FROM_DEVICE); + + dma_async_issue_pending(dma->rxchan); +} + +static void mtk8250_dma_enable(struct uart_8250_port *up) +{ + struct uart_8250_dma *dma = up->dma; + struct mtk8250_data *data = up->port.private_data; + int lcr = serial_in(up, UART_LCR); + + if (data->rx_status != DMA_RX_START) + return; + + dma->rxconf.direction = DMA_DEV_TO_MEM; + dma->rxconf.src_addr_width = dma->rx_size / 1024; + dma->rxconf.src_addr= dma->rx_addr; + + dma->txconf.direction = DMA_MEM_TO_DEV; + dma->txconf.dst_addr_width = MTK_UART_TX_SIZE / 1024; + dma->txconf.dst_addr= dma->tx_addr; + + serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | + UART_FCR_CLEAR_XMIT); + serial_out(up, MTK_UART_DMA_EN, + MTK_UART_DMA_EN_RX | MTK_UART_DMA_EN_TX); + + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + serial_out(up, UART_EFR, UART_EFR_ECB); + serial_out(up, UART_LCR, lcr); + + if