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uboot-1.1.4-kirkwood/board/bmw/ns16550.c

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2024-01-07 23:57:24 +01:00
/*
* COM1 NS16550 support
* originally from linux source (arch/ppc/boot/ns16550.c)
* modified to use CFG_ISA_MEM and new defines
*/
#include <config.h>
#include "ns16550.h"
typedef struct NS16550 *NS16550_t;
const NS16550_t COM_PORTS[] =
{ (NS16550_t) ((CFG_EUMB_ADDR) + 0x4500),
(NS16550_t) ((CFG_EUMB_ADDR) + 0x4600) };
volatile struct NS16550 *NS16550_init (int chan, int baud_divisor)
{
volatile struct NS16550 *com_port;
com_port = (struct NS16550 *) COM_PORTS[chan];
com_port->ier = 0x00;
com_port->lcr = LCR_BKSE; /* Access baud rate */
com_port->dll = baud_divisor & 0xff; /* 9600 baud */
com_port->dlm = (baud_divisor >> 8) & 0xff;
com_port->lcr = LCR_8N1; /* 8 data, 1 stop, no parity */
com_port->mcr = MCR_RTS; /* RTS/DTR */
com_port->fcr = FCR_FIFO_EN | FCR_RXSR | FCR_TXSR; /* Clear & enable FIFOs */
return (com_port);
}
void NS16550_reinit (volatile struct NS16550 *com_port, int baud_divisor)
{
com_port->ier = 0x00;
com_port->lcr = LCR_BKSE; /* Access baud rate */
com_port->dll = baud_divisor & 0xff; /* 9600 baud */
com_port->dlm = (baud_divisor >> 8) & 0xff;
com_port->lcr = LCR_8N1; /* 8 data, 1 stop, no parity */
com_port->mcr = MCR_RTS; /* RTS/DTR */
com_port->fcr = FCR_FIFO_EN | FCR_RXSR | FCR_TXSR; /* Clear & enable FIFOs */
}
void NS16550_putc (volatile struct NS16550 *com_port, unsigned char c)
{
while ((com_port->lsr & LSR_THRE) == 0);
com_port->thr = c;
}
unsigned char NS16550_getc (volatile struct NS16550 *com_port)
{
while ((com_port->lsr & LSR_DR) == 0);
return (com_port->rbr);
}
int NS16550_tstc (volatile struct NS16550 *com_port)
{
return ((com_port->lsr & LSR_DR) != 0);
}