ttyinit.c

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/* ttyinit.c - ttyinit */

#include <xinu.h>

struct ttycblk ttytab[Ntty];

/*------------------------------------------------------------------------
 *  ttyinit  -  Initialize buffers and modes for a tty line
 *------------------------------------------------------------------------
 */
devcall ttyinit(
    struct dentry *devptr /* Entry in device switch table   */
)
{
    struct ttycblk *typtr;   /* Pointer to ttytab entry */
    struct uart_csreg *uptr; /* Address of UART's CSRs  */

    typtr = &ttytab[devptr->dvminor];

    /* Initialize values in the tty control block */

    typtr->tyihead = typtr->tyitail =      /* Set up input queue    */
        &typtr->tyibuff[0];                /*    as empty       */
    typtr->tyisem = semcreate(0);          /* Input semaphore   */
    typtr->tyohead = typtr->tyotail =      /* Set up output queue   */
        &typtr->tyobuff[0];                /*    as empty       */
    typtr->tyosem = semcreate(TY_OBUFLEN); /* Output semaphore  */
    typtr->tyehead = typtr->tyetail =      /* Set up echo queue */
        &typtr->tyebuff[0];                /*    as empty       */
    typtr->tyimode = TY_IMCOOKED;          /* Start in cooked mode  */
    typtr->tyiecho = TRUE;                 /* Echo console input    */
    typtr->tyieback = TRUE;                /* Honor erasing bksp    */
    typtr->tyevis = TRUE;                  /* Visual control chars  */
    typtr->tyecrlf = TRUE;                 /* Echo CRLF for NEWLINE*/
    typtr->tyicrlf = TRUE;                 /* Map CR to NEWLINE */
    typtr->tyierase = TRUE;                /* Do erasing backspace  */
    typtr->tyierasec = TY_BACKSP;          /* Primary erase char    */
    typtr->tyierasec2 = TY_BACKSP2;        /* Alternate erase char  */
    typtr->tyeof = TRUE;                   /* Honor eof on input    */
    typtr->tyeofch = TY_EOFCH;             /* End-of-file character*/
    typtr->tyikill = TRUE;                 /* Allow line kill   */
    typtr->tyikillc = TY_KILLCH;           /* Set line kill to ^U   */
    typtr->tyicursor = 0;                  /* Start of input line   */
    typtr->tyoflow = TRUE;                 /* Handle flow control   */
    typtr->tyoheld = FALSE;                /* Output not held   */
    typtr->tyostop = TY_STOPCH;            /* Stop char is ^S   */
    typtr->tyostart = TY_STRTCH;           /* Start char is ^Q  */
    typtr->tyocrlf = TRUE;                 /* Send CRLF for NEWLINE*/
    typtr->tyifullc = TY_FULLCH;           /* Send ^G when buffer   */
                                           /*   is full     */

    /* Initialize the UART */

    uptr = (struct uart_csreg *)devptr->dvcsr;

    /* Set baud rate */
    uptr->lcr = UART_LCR_DLAB;
    uptr->dlm = UART_DLM;
    uptr->dll = UART_DLL;

    uptr->lcr = UART_LCR_8N1; /* 8 bit char, No Parity, 1 Stop*/
    uptr->fcr = 0x00;         /* Disable FIFO for now       */

    /* Register the interrupt dispatcher for the tty device */

    set_evec(devptr->dvirq, (uint32)devptr->dvintr);

    /* Enable interrupts on the device: reset the transmit and  */
    /*   receive FIFOS, and set the interrupt trigger level     */

    uptr->fcr = UART_FCR_EFIFO | UART_FCR_RRESET |
                UART_FCR_TRESET | UART_FCR_TRIG2;

    /* UART must be in 16x mode (TI AM335X specific) */

    uptr->mdr1 = UART_MDR1_16X;

    /* Start the device */

    ttykickout(uptr);
    return OK;
}