From: Denis V. Lunev Date: Sun, 21 Oct 2012 04:00:30 +0000 (+0800) Subject: tty: serial: KGDB support for PXA X-Git-Tag: firefly_0821_release~3680^2~1518^2~113 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=e1a9c17969f0aa60cb00f1f777b33a07f4e84883;p=firefly-linux-kernel-4.4.55.git tty: serial: KGDB support for PXA Actually, in order to support KGDB over serial console one must implement two callbacks for character polling. Clone them from 8250 driver with a bit of tuning. Signed-off-by: Denis V. Lunev Signed-off-by: Marko Katic CC: Eric Miao CC: Russell King Acked-by: Haojian Zhuang drivers/tty/serial/pxa.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 55 insertions(+), 0 deletions(-) Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/pxa.c b/drivers/tty/serial/pxa.c index 9033fc6e0e4e..2764828251f5 100644 --- a/drivers/tty/serial/pxa.c +++ b/drivers/tty/serial/pxa.c @@ -705,6 +705,57 @@ serial_pxa_console_write(struct console *co, const char *s, unsigned int count) clk_disable_unprepare(up->clk); } +#ifdef CONFIG_CONSOLE_POLL +/* + * Console polling routines for writing and reading from the uart while + * in an interrupt or debug context. + */ + +static int serial_pxa_get_poll_char(struct uart_port *port) +{ + struct uart_pxa_port *up = (struct uart_pxa_port *)port; + unsigned char lsr = serial_in(up, UART_LSR); + + while (!(lsr & UART_LSR_DR)) + lsr = serial_in(up, UART_LSR); + + return serial_in(up, UART_RX); +} + + +static void serial_pxa_put_poll_char(struct uart_port *port, + unsigned char c) +{ + unsigned int ier; + struct uart_pxa_port *up = (struct uart_pxa_port *)port; + + /* + * First save the IER then disable the interrupts + */ + ier = serial_in(up, UART_IER); + serial_out(up, UART_IER, UART_IER_UUE); + + wait_for_xmitr(up); + /* + * Send the character out. + * If a LF, also do CR... + */ + serial_out(up, UART_TX, c); + if (c == 10) { + wait_for_xmitr(up); + serial_out(up, UART_TX, 13); + } + + /* + * Finally, wait for transmitter to become empty + * and restore the IER + */ + wait_for_xmitr(up); + serial_out(up, UART_IER, ier); +} + +#endif /* CONFIG_CONSOLE_POLL */ + static int __init serial_pxa_console_setup(struct console *co, char *options) { @@ -759,6 +810,10 @@ struct uart_ops serial_pxa_pops = { .request_port = serial_pxa_request_port, .config_port = serial_pxa_config_port, .verify_port = serial_pxa_verify_port, +#ifdef CONFIG_CONSOLE_POLL + .poll_get_char = serial_pxa_get_poll_char, + .poll_put_char = serial_pxa_put_poll_char, +#endif }; static struct uart_driver serial_pxa_reg = {