From ef44d28c4fd94166ec6be054359ae26ba73b0291 Mon Sep 17 00:00:00 2001 From: Liang Li Date: Tue, 5 Mar 2013 22:30:38 +0800 Subject: [PATCH] serial: pch_uart: add console poll support Implement console poll for pch_uart, this could enable KGDBoC when on pch-uart console. Signed-off-by: Liang Li Acked-by: Jason Wessel Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/pch_uart.c | 103 ++++++++++++++++++++++++++-------- 1 file changed, 79 insertions(+), 24 deletions(-) diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c index 7a6c989924b3..21a7e179edf3 100644 --- a/drivers/tty/serial/pch_uart.c +++ b/drivers/tty/serial/pch_uart.c @@ -1493,29 +1493,6 @@ static int pch_uart_verify_port(struct uart_port *port, return 0; } -static struct uart_ops pch_uart_ops = { - .tx_empty = pch_uart_tx_empty, - .set_mctrl = pch_uart_set_mctrl, - .get_mctrl = pch_uart_get_mctrl, - .stop_tx = pch_uart_stop_tx, - .start_tx = pch_uart_start_tx, - .stop_rx = pch_uart_stop_rx, - .enable_ms = pch_uart_enable_ms, - .break_ctl = pch_uart_break_ctl, - .startup = pch_uart_startup, - .shutdown = pch_uart_shutdown, - .set_termios = pch_uart_set_termios, -/* .pm = pch_uart_pm, Not supported yet */ -/* .set_wake = pch_uart_set_wake, Not supported yet */ - .type = pch_uart_type, - .release_port = pch_uart_release_port, - .request_port = pch_uart_request_port, - .config_port = pch_uart_config_port, - .verify_port = pch_uart_verify_port -}; - -#ifdef CONFIG_SERIAL_PCH_UART_CONSOLE - /* * Wait for transmitter & holding register to empty */ @@ -1547,6 +1524,84 @@ static void wait_for_xmitr(struct eg20t_port *up, int bits) } } +#ifdef CONFIG_CONSOLE_POLL +/* + * Console polling routines for communicate via uart while + * in an interrupt or debug context. + */ +static int pch_uart_get_poll_char(struct uart_port *port) +{ + struct eg20t_port *priv = + container_of(port, struct eg20t_port, port); + u8 lsr = ioread8(priv->membase + UART_LSR); + + if (!(lsr & UART_LSR_DR)) + return NO_POLL_CHAR; + + return ioread8(priv->membase + PCH_UART_RBR); +} + + +static void pch_uart_put_poll_char(struct uart_port *port, + unsigned char c) +{ + unsigned int ier; + struct eg20t_port *priv = + container_of(port, struct eg20t_port, port); + + /* + * First save the IER then disable the interrupts + */ + ier = ioread8(priv->membase + UART_IER); + pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_ALL_INT); + + wait_for_xmitr(priv, UART_LSR_THRE); + /* + * Send the character out. + * If a LF, also do CR... + */ + iowrite8(c, priv->membase + PCH_UART_THR); + if (c == 10) { + wait_for_xmitr(priv, UART_LSR_THRE); + iowrite8(13, priv->membase + PCH_UART_THR); + } + + /* + * Finally, wait for transmitter to become empty + * and restore the IER + */ + wait_for_xmitr(priv, BOTH_EMPTY); + iowrite8(ier, priv->membase + UART_IER); +} +#endif /* CONFIG_CONSOLE_POLL */ + +static struct uart_ops pch_uart_ops = { + .tx_empty = pch_uart_tx_empty, + .set_mctrl = pch_uart_set_mctrl, + .get_mctrl = pch_uart_get_mctrl, + .stop_tx = pch_uart_stop_tx, + .start_tx = pch_uart_start_tx, + .stop_rx = pch_uart_stop_rx, + .enable_ms = pch_uart_enable_ms, + .break_ctl = pch_uart_break_ctl, + .startup = pch_uart_startup, + .shutdown = pch_uart_shutdown, + .set_termios = pch_uart_set_termios, +/* .pm = pch_uart_pm, Not supported yet */ +/* .set_wake = pch_uart_set_wake, Not supported yet */ + .type = pch_uart_type, + .release_port = pch_uart_release_port, + .request_port = pch_uart_request_port, + .config_port = pch_uart_config_port, + .verify_port = pch_uart_verify_port, +#ifdef CONFIG_CONSOLE_POLL + .poll_get_char = pch_uart_get_poll_char, + .poll_put_char = pch_uart_put_poll_char, +#endif +}; + +#ifdef CONFIG_SERIAL_PCH_UART_CONSOLE + static void pch_console_putchar(struct uart_port *port, int ch) { struct eg20t_port *priv = @@ -1655,7 +1710,7 @@ static struct console pch_console = { #define PCH_CONSOLE (&pch_console) #else #define PCH_CONSOLE NULL -#endif +#endif /* CONFIG_SERIAL_PCH_UART_CONSOLE */ static struct uart_driver pch_uart_driver = { .owner = THIS_MODULE,