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    /*
     * COM1 NS16550 support
     * originally from linux source (arch/ppc/boot/ns16550.c)
     * modified to use CFG_ISA_MEM and new defines
     */
    
    #include <config.h>
    
    #ifdef CFG_NS16550
    
    #include <ns16550.h>
    
    #define LCRVAL LCR_8N1					/* 8 data, 1 stop, no parity */
    #define MCRVAL (MCR_DTR | MCR_RTS)			/* RTS/DTR */
    #define FCRVAL (FCR_FIFO_EN | FCR_RXSR | FCR_TXSR)	/* Clear & enable FIFOs */
    
    void NS16550_init (NS16550_t com_port, int baud_divisor)
    {
    	com_port->ier = 0x00;
    
    	com_port->mdr1 = 0x7;   /* mode select reset TL16C750*/
    
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    	com_port->lcr = LCR_BKSE | LCRVAL;
    	com_port->dll = baud_divisor & 0xff;
    	com_port->dlm = (baud_divisor >> 8) & 0xff;
    	com_port->lcr = LCRVAL;
    	com_port->mcr = MCRVAL;
    	com_port->fcr = FCRVAL;
    
    #if defined(CONFIG_OMAP1510) || defined(CONFIG_OMAP1610)
    	com_port->mdr1 = 0;	/* select uart mode */
    
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    }
    
    void NS16550_reinit (NS16550_t com_port, int baud_divisor)
    {
    	com_port->ier = 0x00;
    	com_port->lcr = LCR_BKSE;
    	com_port->dll = baud_divisor & 0xff;
    	com_port->dlm = (baud_divisor >> 8) & 0xff;
    	com_port->lcr = LCRVAL;
    	com_port->mcr = MCRVAL;
    	com_port->fcr = FCRVAL;
    }
    
    void NS16550_putc (NS16550_t com_port, char c)
    {
    	while ((com_port->lsr & LSR_THRE) == 0);
    	com_port->thr = c;
    }
    
    char NS16550_getc (NS16550_t com_port)
    {
    	while ((com_port->lsr & LSR_DR) == 0);
    	return (com_port->rbr);
    }
    
    int NS16550_tstc (NS16550_t com_port)
    {
    	return ((com_port->lsr & LSR_DR) != 0);
    }
    
    #endif