diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c index c04618052e53..dae3c16ece09 100644 --- a/drivers/tty/serial/samsung.c +++ b/drivers/tty/serial/samsung.c @@ -83,6 +83,8 @@ static void dbg(const char *fmt, ...) #define S3C24XX_TX_PIO 1 #define S3C24XX_TX_DMA 2 +#define S3C24XX_RX_PIO 1 +#define S3C24XX_RX_DMA 2 /* macros to change one thing to another */ #define tx_enabled(port) ((port)->unused[0]) @@ -373,9 +375,65 @@ void s3c24xx_serial_start_tx(struct uart_port *port) } } +static void s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port *ourport, + struct tty_port *tty, int count) +{ + struct s3c24xx_uart_dma *dma = ourport->dma; + int copied; + + if (!count) + return; + + dma_sync_single_for_cpu(ourport->port.dev, dma->rx_addr, + dma->rx_size, DMA_FROM_DEVICE); + + ourport->port.icount.rx += count; + if (!tty) { + dev_err(ourport->port.dev, "No tty port\n"); + return; + } + copied = tty_insert_flip_string(tty, + ((unsigned char *)(ourport->dma->rx_buf)), count); + if (copied != count) { + WARN_ON(1); + dev_err(ourport->port.dev, "RxData copy to tty layer failed\n"); + } +} + +static int s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port *ourport, + unsigned long ufstat); + +static void uart_rx_drain_fifo(struct s3c24xx_uart_port *ourport) +{ + struct uart_port *port = &ourport->port; + struct tty_port *tty = &port->state->port; + unsigned int ch, ufstat; + unsigned int count; + + ufstat = rd_regl(port, S3C2410_UFSTAT); + count = s3c24xx_serial_rx_fifocnt(ourport, ufstat); + + if (!count) + return; + + while (count-- > 0) { + ch = rd_regb(port, S3C2410_URXH); + + ourport->port.icount.rx++; + tty_insert_flip_char(tty, ch, TTY_NORMAL); + } + + tty_flip_buffer_push(tty); +} + static void s3c24xx_serial_stop_rx(struct uart_port *port) { struct s3c24xx_uart_port *ourport = to_ourport(port); + struct s3c24xx_uart_dma *dma = ourport->dma; + struct tty_port *t = &port->state->port; + struct dma_tx_state state; + enum dma_status dma_status; + unsigned int received; if (rx_enabled(port)) { dbg("s3c24xx_serial_stop_rx: port=%p\n", port); @@ -386,6 +444,17 @@ static void s3c24xx_serial_stop_rx(struct uart_port *port) disable_irq_nosync(ourport->rx_irq); rx_enabled(port) = 0; } + if (dma && dma->rx_chan) { + dmaengine_pause(dma->tx_chan); + dma_status = dmaengine_tx_status(dma->rx_chan, + dma->rx_cookie, &state); + if (dma_status == DMA_IN_PROGRESS || + dma_status == DMA_PAUSED) { + received = dma->rx_bytes_requested - state.residue; + dmaengine_terminate_all(dma->rx_chan); + s3c24xx_uart_copy_rx_to_tty(ourport, t, received); + } + } } static inline struct s3c24xx_uart_info @@ -417,12 +486,157 @@ static int s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port *ourport, return (ufstat & info->rx_fifomask) >> info->rx_fifoshift; } +static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport); +static void s3c24xx_serial_rx_dma_complete(void *args) +{ + struct s3c24xx_uart_port *ourport = args; + struct uart_port *port = &ourport->port; + + struct s3c24xx_uart_dma *dma = ourport->dma; + struct tty_port *t = &port->state->port; + struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port); + + struct dma_tx_state state; + unsigned long flags; + int received; + + dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state); + received = dma->rx_bytes_requested - state.residue; + async_tx_ack(dma->rx_desc); + + spin_lock_irqsave(&port->lock, flags); + + if (received) + s3c24xx_uart_copy_rx_to_tty(ourport, t, received); + + if (tty) { + tty_flip_buffer_push(t); + tty_kref_put(tty); + } + + s3c64xx_start_rx_dma(ourport); + + spin_unlock_irqrestore(&port->lock, flags); +} + +static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport) +{ + struct s3c24xx_uart_dma *dma = ourport->dma; + + dma_sync_single_for_device(ourport->port.dev, dma->rx_addr, + dma->rx_size, DMA_FROM_DEVICE); + + dma->rx_desc = dmaengine_prep_slave_single(dma->rx_chan, + dma->rx_addr, dma->rx_size, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT); + if (!dma->rx_desc) { + dev_err(ourport->port.dev, "Unable to get desc for Rx\n"); + return; + } + + dma->rx_desc->callback = s3c24xx_serial_rx_dma_complete; + dma->rx_desc->callback_param = ourport; + dma->rx_bytes_requested = dma->rx_size; + + dma->rx_cookie = dmaengine_submit(dma->rx_desc); + dma_async_issue_pending(dma->rx_chan); +} /* ? - where has parity gone?? */ #define S3C2410_UERSTAT_PARITY (0x1000) -static irqreturn_t -s3c24xx_serial_rx_chars(int irq, void *dev_id) +static void enable_rx_dma(struct s3c24xx_uart_port *ourport) +{ + struct uart_port *port = &ourport->port; + unsigned int ucon; + + /* set Rx mode to DMA mode */ + ucon = rd_regl(port, S3C2410_UCON); + ucon &= ~(S3C64XX_UCON_RXBURST_MASK | + S3C64XX_UCON_TIMEOUT_MASK | + S3C64XX_UCON_EMPTYINT_EN | + S3C64XX_UCON_DMASUS_EN | + S3C64XX_UCON_TIMEOUT_EN | + S3C64XX_UCON_RXMODE_MASK); + ucon |= S3C64XX_UCON_RXBURST_16 | + 0xf << S3C64XX_UCON_TIMEOUT_SHIFT | + S3C64XX_UCON_EMPTYINT_EN | + S3C64XX_UCON_TIMEOUT_EN | + S3C64XX_UCON_RXMODE_DMA; + wr_regl(port, S3C2410_UCON, ucon); + + ourport->rx_mode = S3C24XX_RX_DMA; +} + +static void enable_rx_pio(struct s3c24xx_uart_port *ourport) +{ + struct uart_port *port = &ourport->port; + unsigned int ucon; + + /* set Rx mode to DMA mode */ + ucon = rd_regl(port, S3C2410_UCON); + ucon &= ~(S3C64XX_UCON_TIMEOUT_MASK | + S3C64XX_UCON_EMPTYINT_EN | + S3C64XX_UCON_DMASUS_EN | + S3C64XX_UCON_TIMEOUT_EN | + S3C64XX_UCON_RXMODE_MASK); + ucon |= 0xf << S3C64XX_UCON_TIMEOUT_SHIFT | + S3C64XX_UCON_TIMEOUT_EN | + S3C64XX_UCON_RXMODE_CPU; + wr_regl(port, S3C2410_UCON, ucon); + + ourport->rx_mode = S3C24XX_RX_PIO; +} + +static irqreturn_t s3c24xx_serial_rx_chars_dma(int irq, void *dev_id) +{ + unsigned int utrstat, ufstat, received; + struct s3c24xx_uart_port *ourport = dev_id; + struct uart_port *port = &ourport->port; + struct s3c24xx_uart_dma *dma = ourport->dma; + struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port); + struct tty_port *t = &port->state->port; + unsigned long flags; + struct dma_tx_state state; + + utrstat = rd_regl(port, S3C2410_UTRSTAT); + ufstat = rd_regl(port, S3C2410_UFSTAT); + + spin_lock_irqsave(&port->lock, flags); + + if (!(utrstat & S3C2410_UTRSTAT_TIMEOUT)) { + s3c64xx_start_rx_dma(ourport); + if (ourport->rx_mode == S3C24XX_RX_PIO) + enable_rx_dma(ourport); + goto finish; + } + + if (ourport->rx_mode == S3C24XX_RX_DMA) { + dmaengine_pause(dma->rx_chan); + dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state); + dmaengine_terminate_all(dma->rx_chan); + received = dma->rx_bytes_requested - state.residue; + s3c24xx_uart_copy_rx_to_tty(ourport, t, received); + + enable_rx_pio(ourport); + } + + uart_rx_drain_fifo(ourport); + + if (tty) { + tty_flip_buffer_push(t); + tty_kref_put(tty); + } + + wr_regl(port, S3C2410_UTRSTAT, S3C2410_UTRSTAT_TIMEOUT); + +finish: + spin_unlock_irqrestore(&port->lock, flags); + + return IRQ_HANDLED; +} + +static irqreturn_t s3c24xx_serial_rx_chars_pio(int irq, void *dev_id) { struct s3c24xx_uart_port *ourport = dev_id; struct uart_port *port = &ourport->port; @@ -513,6 +727,16 @@ out: return IRQ_HANDLED; } + +static irqreturn_t s3c24xx_serial_rx_chars(int irq, void *dev_id) +{ + struct s3c24xx_uart_port *ourport = dev_id; + + if (ourport->dma && ourport->dma->rx_chan) + return s3c24xx_serial_rx_chars_dma(irq, dev_id); + return s3c24xx_serial_rx_chars_pio(irq, dev_id); +} + static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id) { struct s3c24xx_uart_port *ourport = id; @@ -818,6 +1042,8 @@ err: static int s3c64xx_serial_startup(struct uart_port *port) { struct s3c24xx_uart_port *ourport = to_ourport(port); + unsigned long flags; + unsigned int ufcon; int ret; dbg("s3c64xx_serial_startup: port=%p (%08llx,%p)\n", @@ -848,7 +1074,8 @@ static int s3c64xx_serial_startup(struct uart_port *port) spin_lock_irqsave(&port->lock, flags); ufcon = rd_regl(port, S3C2410_UFCON); - ufcon |= S3C2410_UFCON_RESETRX | S3C2410_UFCON_RESETTX; + ufcon |= S3C2410_UFCON_RESETRX | S3C2410_UFCON_RESETTX | + S5PV210_UFCON_RXTRIG8; wr_regl(port, S3C2410_UFCON, ufcon); enable_rx_pio(ourport); diff --git a/drivers/tty/serial/samsung.h b/drivers/tty/serial/samsung.h index e60011c591e8..d275032aa68d 100644 --- a/drivers/tty/serial/samsung.h +++ b/drivers/tty/serial/samsung.h @@ -88,6 +88,7 @@ struct s3c24xx_uart_port { unsigned int tx_in_progress; unsigned int tx_mode; + unsigned int rx_mode; struct s3c24xx_uart_info *info; struct clk *clk;