From: TsiChung Liew <Tsi-Chung.Liew@freescale.com>
Date: Thu, 29 May 2008 17:21:54 +0000 (-0500)
Subject: ColdFire: Fix UART baudrate formula
X-Git-Tag: v1.3.4-rc1~40^2^2~12
X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=81cc32322acb1b3225ee45606ced48e2a14824dc;p=u-boot

ColdFire: Fix UART baudrate formula

The formula "counter = (u32) (gd->bus_clk / gd->baudrate) / 32"
can generate the wrong divisor due to integer division truncation.
Round the calculated divisor value by adding 1/2 the baudrate
before dividing by the baudrate.

Signed-off-by: TsiChung Liew <Tsi-Chung.Liew@freescale.com>
Acked-by: Gerald Van Baren <vanbaren@cideas.com>
---

diff --git a/drivers/serial/mcfuart.c b/drivers/serial/mcfuart.c
index 88f3eb10ab..5eb4f458f8 100644
--- a/drivers/serial/mcfuart.c
+++ b/drivers/serial/mcfuart.c
@@ -63,8 +63,8 @@ int serial_init(void)
 	uart->umr = UART_UMR_SB_STOP_BITS_1;
 
 	/* Setting up BaudRate */
-	counter = (u32) (gd->bus_clk / (gd->baudrate));
-	counter >>= 5;
+	counter = (u32) ((gd->bus_clk / 32) + (gd->baudrate / 2));
+	counter = counter / gd->baudrate;
 
 	/* write to CTUR: divide counter upper byte */
 	uart->ubg1 = (u8) ((counter & 0xff00) >> 8);