diff options
| -rw-r--r-- | drivers/tty/serial/xilinx_uartps.c | 219 |
1 files changed, 114 insertions, 105 deletions
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c index 98f7b590ec55..511999755f5c 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -198,58 +198,43 @@ struct cdns_platform_data { #define to_cdns_uart(_nb) container_of(_nb, struct cdns_uart, \ clk_rate_change_nb); -static void cdns_uart_handle_rx(struct uart_port *port, unsigned int isrstatus) +/** + * cdns_uart_handle_rx - Handle the received bytes along with Rx errors. + * @dev_id: Id of the UART port + * @isrstatus: The interrupt status register value as read + * Return: None + */ +static void cdns_uart_handle_rx(void *dev_id, unsigned int isrstatus) { + struct uart_port *port = (struct uart_port *)dev_id; struct cdns_uart *cdns_uart = port->private_data; - bool is_rxbs_support; + unsigned int data; unsigned int rxbs_status = 0; unsigned int status_mask; + unsigned int framerrprocessed = 0; + char status = TTY_NORMAL; + bool is_rxbs_support; is_rxbs_support = cdns_uart->quirks & CDNS_UART_RXBS_SUPPORT; - /* - * There is no hardware break detection, so we interpret framing - * error with all-zeros data as a break sequence. Most of the time, - * there's another non-zero byte at the end of the sequence. - */ - if (!is_rxbs_support && (isrstatus & CDNS_UART_IXR_FRAMING)) { - while (!(readl(port->membase + CDNS_UART_SR) & - CDNS_UART_SR_RXEMPTY)) { - if (!readl(port->membase + CDNS_UART_FIFO)) { - port->read_status_mask |= CDNS_UART_IXR_BRK; - isrstatus &= ~CDNS_UART_IXR_FRAMING; - } - } - writel(CDNS_UART_IXR_FRAMING, port->membase + CDNS_UART_ISR); - } - - /* drop byte with parity error if IGNPAR specified */ - if (isrstatus & port->ignore_status_mask & CDNS_UART_IXR_PARITY) - isrstatus &= ~(CDNS_UART_IXR_RXTRIG | CDNS_UART_IXR_TOUT); - - isrstatus &= port->read_status_mask; - isrstatus &= ~port->ignore_status_mask; - status_mask = port->read_status_mask; - status_mask &= ~port->ignore_status_mask; - - if (!(isrstatus & (CDNS_UART_IXR_TOUT | CDNS_UART_IXR_RXTRIG))) - return; - - while (!(readl(port->membase + CDNS_UART_SR) & CDNS_UART_SR_RXEMPTY)) { - u32 data; - char status = TTY_NORMAL; - + while ((readl(port->membase + CDNS_UART_SR) & + CDNS_UART_SR_RXEMPTY) != CDNS_UART_SR_RXEMPTY) { if (is_rxbs_support) rxbs_status = readl(port->membase + CDNS_UART_RXBS); - data = readl(port->membase + CDNS_UART_FIFO); - - /* Non-NULL byte after BREAK is garbage (99%) */ - if (data && (port->read_status_mask & CDNS_UART_IXR_BRK)) { - port->read_status_mask &= ~CDNS_UART_IXR_BRK; - port->icount.brk++; - if (uart_handle_break(port)) + port->icount.rx++; + /* + * There is no hardware break detection in Zynq, so we interpret + * framing error with all-zeros data as a break sequence. + * Most of the time, there's another non-zero byte at the + * end of the sequence. + */ + if (!is_rxbs_support && (isrstatus & CDNS_UART_IXR_FRAMING)) { + if (!data) { + port->read_status_mask |= CDNS_UART_IXR_BRK; + framerrprocessed = 1; continue; + } } if (is_rxbs_support && (rxbs_status & CDNS_UART_RXBS_BRK)) { port->icount.brk++; @@ -258,74 +243,101 @@ static void cdns_uart_handle_rx(struct uart_port *port, unsigned int isrstatus) continue; } - if (uart_handle_sysrq_char(port, data)) - continue; + isrstatus &= port->read_status_mask; + isrstatus &= ~port->ignore_status_mask; + status_mask = port->read_status_mask; + status_mask &= ~port->ignore_status_mask; + + if ((isrstatus & CDNS_UART_IXR_TOUT) || + (isrstatus & CDNS_UART_IXR_RXTRIG)) { + if (data && + (port->read_status_mask & CDNS_UART_IXR_BRK)) { + port->read_status_mask &= ~CDNS_UART_IXR_BRK; + port->icount.brk++; + if (uart_handle_break(port)) + continue; + } - port->icount.rx++; + if (uart_handle_sysrq_char(port, data)) + continue; - if (is_rxbs_support) { - if ((rxbs_status & CDNS_UART_RXBS_PARITY) - && (status_mask & CDNS_UART_IXR_PARITY)) { - port->icount.parity++; - status = TTY_PARITY; + if (is_rxbs_support) { + if ((rxbs_status & CDNS_UART_RXBS_PARITY) + && (status_mask & CDNS_UART_IXR_PARITY)) { + port->icount.parity++; + status = TTY_PARITY; + } + if ((rxbs_status & CDNS_UART_RXBS_FRAMING) + && (status_mask & CDNS_UART_IXR_PARITY)) { + port->icount.frame++; + status = TTY_FRAME; + } + } else { + if (isrstatus & CDNS_UART_IXR_PARITY) { + port->icount.parity++; + status = TTY_PARITY; + } + if ((isrstatus & CDNS_UART_IXR_FRAMING) && + !framerrprocessed) { + port->icount.frame++; + status = TTY_FRAME; + } } - if ((rxbs_status & CDNS_UART_RXBS_FRAMING) - && (status_mask & CDNS_UART_IXR_PARITY)) { - port->icount.frame++; - status = TTY_FRAME; - } - } else { - if (isrstatus & CDNS_UART_IXR_PARITY) { - port->icount.parity++; - status = TTY_PARITY; - } - if (isrstatus & CDNS_UART_IXR_FRAMING) { - port->icount.frame++; - status = TTY_FRAME; + if (isrstatus & CDNS_UART_IXR_OVERRUN) { + port->icount.overrun++; + tty_insert_flip_char(&port->state->port, 0, + TTY_OVERRUN); } + tty_insert_flip_char(&port->state->port, data, status); } - if (isrstatus & CDNS_UART_IXR_OVERRUN) - port->icount.overrun++; - - uart_insert_char(port, isrstatus, CDNS_UART_IXR_OVERRUN, - data, status); } + spin_unlock(&port->lock); tty_flip_buffer_push(&port->state->port); + spin_lock(&port->lock); } -static void cdns_uart_handle_tx(struct uart_port *port) +/** + * cdns_uart_handle_tx - Handle the bytes to be Txed. + * @dev_id: Id of the UART port + * Return: None + */ +static void cdns_uart_handle_tx(void *dev_id) { + struct uart_port *port = (struct uart_port *)dev_id; unsigned int numbytes; if (uart_circ_empty(&port->state->xmit)) { writel(CDNS_UART_IXR_TXEMPTY, port->membase + CDNS_UART_IDR); - return; - } - - numbytes = port->fifosize; - while (numbytes && !uart_circ_empty(&port->state->xmit) && - !(readl(port->membase + CDNS_UART_SR) & CDNS_UART_SR_TXFULL)) { - /* - * Get the data from the UART circular buffer - * and write it to the cdns_uart's TX_FIFO - * register. - */ - writel(port->state->xmit.buf[port->state->xmit.tail], - port->membase + CDNS_UART_FIFO); - port->icount.tx++; - - /* - * Adjust the tail of the UART buffer and wrap - * the buffer if it reaches limit. - */ - port->state->xmit.tail = - (port->state->xmit.tail + 1) & (UART_XMIT_SIZE - 1); + } else { + numbytes = port->fifosize; + while (numbytes && !uart_circ_empty(&port->state->xmit) && + !(readl(port->membase + CDNS_UART_SR) & CDNS_UART_SR_TXFULL)) { + /* + * Get the data from the UART circular buffer + * and write it to the cdns_uart's TX_FIFO + * register. + */ + writel( + port->state->xmit.buf[port->state->xmit. + tail], port->membase + CDNS_UART_FIFO); + + port->icount.tx++; + + /* + * Adjust the tail of the UART buffer and wrap + * the buffer if it reaches limit. + */ + port->state->xmit.tail = + (port->state->xmit.tail + 1) & + (UART_XMIT_SIZE - 1); + + numbytes--; + } - numbytes--; + if (uart_circ_chars_pending( + &port->state->xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); } - - if (uart_circ_chars_pending(&port->state->xmit) < WAKEUP_CHARS) - uart_write_wakeup(port); } /** @@ -338,27 +350,24 @@ static void cdns_uart_handle_tx(struct uart_port *port) static irqreturn_t cdns_uart_isr(int irq, void *dev_id) { struct uart_port *port = (struct uart_port *)dev_id; - unsigned long flags; unsigned int isrstatus; - spin_lock_irqsave(&port->lock, flags); + spin_lock(&port->lock); /* Read the interrupt status register to determine which - * interrupt(s) is/are active. + * interrupt(s) is/are active and clear them. */ isrstatus = readl(port->membase + CDNS_UART_ISR); - - if (isrstatus & CDNS_UART_RX_IRQS) - cdns_uart_handle_rx(port, isrstatus); - - if ((isrstatus & CDNS_UART_IXR_TXEMPTY) == CDNS_UART_IXR_TXEMPTY) - cdns_uart_handle_tx(port); - writel(isrstatus, port->membase + CDNS_UART_ISR); - /* be sure to release the lock and tty before leaving */ - spin_unlock_irqrestore(&port->lock, flags); + if (isrstatus & CDNS_UART_IXR_TXEMPTY) { + cdns_uart_handle_tx(dev_id); + isrstatus &= ~CDNS_UART_IXR_TXEMPTY; + } + if (isrstatus & CDNS_UART_IXR_MASK) + cdns_uart_handle_rx(dev_id, isrstatus); + spin_unlock(&port->lock); return IRQ_HANDLED; } |