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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>
TsiChung Liew 17 years ago
parent
commit
81cc32322a
1 changed files with 2 additions and 2 deletions
  1. 2 2
      drivers/serial/mcfuart.c

+ 2 - 2
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);