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m68knommu: fix ColdFire 5272 serial baud rates in mcf.c
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I noticed (the hard way) that the mcf.c driver doesn't support the fractional precision register on the MCF5272.  This makes the console dicey at 115200 baud and a system clock of 66.0 MHz.  On the other hand, if your hardware is running at 66.666 MHz, it probably isn't a problem.

Patch submitted by John Adamson <jadamson@allen-organ.com>

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
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John Adamson authored and Greg Ungerer committed Jan 27, 2009
1 parent c7bcd0d commit 26a4bc6
Showing 1 changed file with 11 additions and 0 deletions.
11 changes: 11 additions & 0 deletions drivers/serial/mcf.c
Original file line number Diff line number Diff line change
Expand Up @@ -212,10 +212,18 @@ static void mcf_set_termios(struct uart_port *port, struct ktermios *termios,
{
unsigned long flags;
unsigned int baud, baudclk;
#if defined(CONFIG_M5272)
unsigned int baudfr;
#endif
unsigned char mr1, mr2;

baud = uart_get_baud_rate(port, termios, old, 0, 230400);
#if defined(CONFIG_M5272)
baudclk = (MCF_BUSCLK / baud) / 32;
baudfr = (((MCF_BUSCLK / baud) + 1) / 2) % 16;
#else
baudclk = ((MCF_BUSCLK / baud) + 16) / 32;
#endif

mr1 = MCFUART_MR1_RXIRQRDY | MCFUART_MR1_RXERRCHAR;
mr2 = 0;
Expand Down Expand Up @@ -262,6 +270,9 @@ static void mcf_set_termios(struct uart_port *port, struct ktermios *termios,
writeb(mr2, port->membase + MCFUART_UMR);
writeb((baudclk & 0xff00) >> 8, port->membase + MCFUART_UBG1);
writeb((baudclk & 0xff), port->membase + MCFUART_UBG2);
#if defined(CONFIG_M5272)
writeb((baudfr & 0x0f), port->membase + MCFUART_UFPD);
#endif
writeb(MCFUART_UCSR_RXCLKTIMER | MCFUART_UCSR_TXCLKTIMER,
port->membase + MCFUART_UCSR);
writeb(MCFUART_UCR_RXENABLE | MCFUART_UCR_TXENABLE,
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