serial: pl01x: drain PL01x FIFO before baudrate change

Not draining the FIFO and waiting for the UART to be non-busy
before changing baudrate results in crap characters on the
console, so let's wait for the FIFO to drain and the last
character to be clocked out before we do that.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Linus Walleij 2011-10-02 11:52:52 +00:00 committed by Wolfgang Denk
parent 349e83f071
commit 96baa4c376
1 changed files with 10 additions and 0 deletions

View File

@ -194,7 +194,17 @@ int serial_tstc (void)
void serial_setbrg (void)
{
struct pl01x_regs *regs = pl01x_get_regs(CONSOLE_PORT);
baudrate = gd->baudrate;
/*
* Flush FIFO and wait for non-busy before changing baudrate to avoid
* crap in console
*/
while (!(readl(&regs->fr) & UART_PL01x_FR_TXFE))
WATCHDOG_RESET();
while (readl(&regs->fr) & UART_PL01x_FR_BUSY)
WATCHDOG_RESET();
serial_init();
}