diff options
| author | Michal Simek <michal.simek@xilinx.com> | 2014-05-06 06:46:15 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-05-28 12:24:31 -0700 |
| commit | d3352154041e28cf8c1c260cca41d8e83d5377d8 (patch) | |
| tree | d7ff0426499201491c308564ee592877e9b064e8 | |
| parent | ac62391496cf1ace051c4daebb00f7435320f11f (diff) | |
tty: serial: uartlite: Specify time for sending chars
Xilinx MDM (Microblaze Debug Module) also contains
uart interface via JTAG which is compatible with
uartlite driver. This interface is really slow
that's why timeout is setup to 1s.
Make this time delay not to be cpu speed dependent.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/serial/uartlite.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/drivers/tty/serial/uartlite.c b/drivers/tty/serial/uartlite.c index 5f90ef24d47..dce27f34937 100644 --- a/drivers/tty/serial/uartlite.c +++ b/drivers/tty/serial/uartlite.c @@ -418,14 +418,23 @@ static struct uart_ops ulite_ops = { #ifdef CONFIG_SERIAL_UARTLITE_CONSOLE static void ulite_console_wait_tx(struct uart_port *port) { - int i; u8 val; - - /* Spin waiting for TX fifo to have space available */ - for (i = 0; i < 100000; i++) { + unsigned long timeout; + + /* + * Spin waiting for TX fifo to have space available. + * When using the Microblaze Debug Module this can take up to 1s + */ + timeout = jiffies + msecs_to_jiffies(1000); + while (1) { val = uart_in32(ULITE_STATUS, port); if ((val & ULITE_STATUS_TXFULL) == 0) break; + if (time_after(jiffies, timeout)) { + dev_warn(port->dev, + "timeout waiting for TX buffer empty\n"); + break; + } cpu_relax(); } } |