commit 96baa4c37695b4dac2bde981f59c38e7af19f2eb
author Linus Walleij <linus.walleij@linaro.org> Sun Oct 02 11:52:52 2011 +0000
committer Wolfgang Denk <wd@denx.de> Sat Oct 22 00:42:04 2011 +0200
tree 4c9c24511165b0571d8ac9579a982ba03483fd1e
parent 349e83f071e2bf7bd9fec50377bbdcfb1a143666

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>

drivers/serial/serial_pl01x.c

diff --git a/drivers/serial/serial_pl01x.c b/drivers/serial/serial_pl01x.c
index 7a064ff..ed581ae 100644
--- a/drivers/serial/serial_pl01x.c
+++ b/drivers/serial/serial_pl01x.c
@@ -194,7 +194,17 @@
 
 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();
 }