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>
This commit is contained in:
TsiChung Liew 2008-05-29 12:21:54 -05:00 committed by John Rigby
parent 9b55a25369
commit 81cc32322a

View File

@ -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);