ixp425sio.c

INTEL IXP425的VXWORKS BSP

/* ixp425Sio.c - IXP425 UART tty driver */

/* Copyright 2002 Wind River Systems, Inc. */

#include "copyright_wrs.h"

/*
modification history
--------------------
01d,31jan03,jb3  Fix warning: unused variable .
01c,30jan03,jb3  Fix SPR 85040 Serialdata corruption.
01b,06nov02,jb  Fix compile warning
01a,05jun02,jb  initial version...
*/

/*
DESCRIPTION
This is the driver for the Intel IXP425 internal UART. This device comprises an 
asynchronous receiver/transmitter, a baud rate generator, and some modem control 
capability. 

An IXP425_SIO_CHAN structure is used to describe the serial channel. This data 
structure is defined in ixp425Sio.h.

Only asynchronous serial operation is supported by this driver.
The default serial settings are 8 data bits, 1 stop bit, no parity, 9600
baud, and software flow control.  

USAGE
The BSP's sysHwInit() routine typically calls sysSerialHwInit(),
which creates the IXP425_SIO_CHAN structure and initializes all the values in the
structure (except the SIO_DRV_FUNCS) before calling ixp425SioDevInit().
The BSP's sysHwInit2() routine typically calls sysSerialHwInit2(), which
connects the chips interrupts via intConnect() (either the single
interrupt 'ixp425SioInt' or the two interrupts 'ixp425SioIntWr', 'ixp425SioIntRd').

This driver handles setting of hardware options such as parity(odd, even) and
number of data bits(5, 6, 7, 8). Hardware flow control is provided with the
handshakes RTS/CTS.

INCLUDE FILES: ixp425Sio.h

SEE ALSO:
.I "ixp425 Data Sheet,"
*/

/* includes */

#include "vxWorks.h"
#include "intLib.h"
#include "errnoLib.h"
#include "errno.h"
#include "sioLib.h"
#include "stdio.h"
#include "ixp425Sio.h"

#define IXP425_SIO_MIN_RATE 9600
#define IXP425_SIO_MAX_RATE 921600
#define IXP425_SIO_DEF_OPTS (CLOCAL | CREAD | CS8)

#define REG(reg, pchan) \
 (*(volatile UINT32 *)((UINT32)pchan->regs + (reg * pchan->regDelta)))

#define REGPTR(reg, pchan) \
 ((volatile UINT32 *)((UINT32)pchan->regs + (reg * pchan->regDelta)))

/* for backward compatibility */

#ifndef	SIO_HUP
    #define SIO_OPEN	0x100A	/* open channel, raise DTR, RTS */
    #define SIO_HUP	0x100B	/* hang-up, lower DTR, RTS */
#endif

/* static forward declarations */

LOCAL 	int 	ixp425SioCallbackInstall (SIO_CHAN *, int, STATUS (*)(), void *);
LOCAL 	STATUS 	ixp425SioDummyCallback ();
LOCAL 	void 	ixp425SioInitChannel (IXP425_SIO_CHAN *);
LOCAL   STATUS  ixp425SioBaudSet (IXP425_SIO_CHAN *, UINT);
LOCAL 	STATUS  ixp425SioModeSet (IXP425_SIO_CHAN *, UINT);
LOCAL 	STATUS 	ixp425SioIoctl (IXP425_SIO_CHAN *, int, int);
LOCAL 	void 	ixp425SioTxStartup (IXP425_SIO_CHAN *);
LOCAL 	int 	ixp425SioPollOutput (IXP425_SIO_CHAN *, char);
LOCAL 	int 	ixp425SioPollInput (IXP425_SIO_CHAN *, char *);
LOCAL 	STATUS 	ixp425SioOptsSet (IXP425_SIO_CHAN *, UINT);
LOCAL	void	ixp425SioIntRd (IXP425_SIO_CHAN * pChan);

/* driver functions */

static SIO_DRV_FUNCS ixp425SioDrvFuncs =
    {
    (int (*)())ixp425SioIoctl,
    (int (*)())ixp425SioTxStartup,
    (int (*)())ixp425SioCallbackInstall,
    (int (*)())ixp425SioPollInput,
    (int (*)(SIO_CHAN *,char))ixp425SioPollOutput
    };


/******************************************************************************
*
* ixp425SioDummyCallback - dummy callback routine.
*/
LOCAL STATUS ixp425SioDummyCallback (void)
    {
    return (ERROR);
    }

/******************************************************************************
*
* ixp425SioDevInit - initialise a UART channel
*
* This routine initialises some SIO_CHAN function pointers and then resets
* the chip in a quiescent state.  Before this routine is called, the BSP
* must already have initialised all the device addresses, etc. in the
* IXP425_SIO_CHAN structure.
*
* RETURNS: N/A
*/
void ixp425SioDevInit
    (
    IXP425_SIO_CHAN * pChan	/* pointer to channel */
    )
    {
    int oldlevel = intLock ();

    /* Initialise the driver function pointers in the SIO_CHAN's */
    pChan->pDrvFuncs = &ixp425SioDrvFuncs;

#ifdef IXP425_SIO_DEBUG
    /* Initialise counter statistics */
    pChan->rxCount = 0;
    pChan->txCount = 0;
    pChan->overrunErr = 0;
    pChan->parityErr = 0;
    pChan->framingErr = 0;
    pChan->breakErr = 0;
#endif

    /* Set the non BSP-specific constants */
    pChan->getTxChar    = ixp425SioDummyCallback;
    pChan->putRcvChar   = ixp425SioDummyCallback;
    pChan->options      = IXP425_SIO_DEF_OPTS;
    pChan->mcr		= MCR_OUT2;

    /* 
     * Mode 0 is undefined. However the VxWorks ttyDrv will issue
     * an ioctl for mode set to change to interrupt mode when it 
     * needs to use the UART.
     */ 
    pChan->channelMode  = 0;

    /* Enable the device */
    pChan->ier = IER_UUE;

    /* Set hardware opts and baud rate */
    ixp425SioInitChannel (pChan);

    intUnlock (oldlevel);
    }

/*******************************************************************************
*
* ixp425SioInitChannel - initialise UART
*
* Initialise the number of data bits, parity and set the selected
* baud rate. Set the modem control signals if the option is selected.
*
* RETURNS: N/A
*/
LOCAL void ixp425SioInitChannel
    (
    IXP425_SIO_CHAN * pChan	/* pointer to channel */
    )
    {
    /* set the requested baud rate */
    ixp425SioBaudSet(pChan, pChan->baudRate);

    /* set the options */
    ixp425SioOptsSet(pChan, pChan->options);
    }

/*******************************************************************************
*
* ixp425SioOptsSet - set the serial options
*
* Set the channel operating mode to that specified.  The following sioLib options
* are supported: CLOCAL, CREAD, CSIZE, PARENB, and PARODD.
* The HUPCL option is not supported for now.
*
* Note, this routine disables the transmitter.  The calling routine
* may have to re-enable it.
*
* RETURNS:
* Returns OK to indicate success, otherwise ERROR is returned
*/
LOCAL STATUS ixp425SioOptsSet
    (
    IXP425_SIO_CHAN * pChan,	/* pointer to channel */
    UINT options		/* new hardware options */
    )
    {
    FAST int     oldlevel;	/* current interrupt level mask */

    pChan->lcr = 0; 
    pChan->mcr &= (~MCR_RTS);	/* clear RTS bit */
    
    if (pChan == NULL || options & 0xffffff00)
	return ERROR;

    switch (options & CSIZE)
	{
	case CS5:
	    pChan->lcr = CHAR_LEN_5; break;
	case CS6:
	    pChan->lcr = CHAR_LEN_6; break;
	case CS7:
	    pChan->lcr = CHAR_LEN_7; break;
	case CS8:
	default:
	    pChan->lcr = CHAR_LEN_8; break;
	}

    if (options & STOPB)
	pChan->lcr |= LCR_STB_2;
    else
	pChan->lcr |= LCR_STB_1;
    
    switch (options & (PARENB | PARODD))
	{
	case PARENB|PARODD:
	    pChan->lcr |= LCR_PEN; break;
	case PARENB:
	    pChan->lcr |= (LCR_PEN | LCR_EPS); break;
	default:
	case 0:
	    pChan->lcr |= LCR_PDIS; break;
	}

    REG(IER, pChan) = IER_UUE; /* disable interrupts, enable UART */

    if (!(options & CLOCAL))	/* use hardware flow control (RTS/CTS) */
	{
	pChan->mcr |= MCR_RTS;
    	pChan->ier &= (~IER_TIE); 
	pChan->ier |= IER_MIE;  /* enable modem status interrupt */
	}
    else
        pChan->ier &= (~IER_MIE); /* software flow ctrl */ 

    oldlevel = intLock();

    REG(LCR, pChan) = (unsigned int) pChan->lcr;
    REG(MCR, pChan) = (unsigned int) pChan->mcr;

    /* Enable FIFOs and set trigger level */
    REG(FCR, pChan) = (unsigned int) (FCR_RESETRF | FCR_RESETTF | FCR_TRFIFOE | FCR_ITL_32);/* (FCR_ITL_32); */

    if (options & CREAD)  
	pChan->ier |= (IER_RAVIE | IER_RTOIE);

    if (pChan->channelMode == SIO_MODE_INT)
	{
	pChan->ier |= IER_RLSE;
        REG(IER, pChan) = (unsigned int) pChan->ier;
        }

    intUnlock (oldlevel);

    pChan->options = options;

    return OK;
    }
    
/******************************************************************************
*
* ixp425SioBaudSet - change baud rate for channel
*
* This routine sets the baud rate for the UART. The interrupts are disabled
* during chip access.
*
* RETURNS: OK
*/
LOCAL STATUS  ixp425SioBaudSet
    (
    IXP425_SIO_CHAN * pChan,	/* pointer to channel */
    UINT	   baud		/* requested baud rate */
    )
    {
    FAST int   oldlevel;

    /* disable interrupts during chip access */

    oldlevel = intLock ();

    /* Enable access to the divisor latches by setting DLAB in LCR. */

    REG(LCR, pChan) = (unsigned int) (LCR_DLAB | pChan->lcr);

    /* Set divisor latches. */

    REG(DLL, pChan) = (unsigned int) (pChan->xtal/(16 * baud));
    REG(DLM, pChan) = (unsigned int) ((pChan->xtal/(16 * baud)) >> 8);

    /* Restore line control register */

    REG(LCR, pChan) = (unsigned int) pChan->lcr;

    pChan->baudRate = baud;
 
    intUnlock (oldlevel);

    return (OK);
    }

/*******************************************************************************
*
* ixp425SioModeSet - change channel mode setting
*
* This driver supports both polled and interrupt modes and is capable of
* switching between modes dynamically. 
*
* If interrupt mode is desired this routine enables the channel's receiver 
* interrupt. The transmitter interrupt is enabled in TxStartup(). If the modem 
* control option is TRUE, the Tx interrupt is disabled if the CTS signal is FALSE.
* It is enabled otherwise. 
*
* If polled mode is desired the device interrupts are disabled. 
*
* RETURNS:
* Returns a status of OK if the mode was set else ERROR.
*/

LOCAL STATUS ixp425SioModeSet
    (
    IXP425_SIO_CHAN * pChan,	/* pointer to channel */
    UINT	newMode		/* mode requested */
    )
    {
    FAST int     oldlevel;	/* current interrupt level mask */
    char mask;

    if ((newMode != SIO_MODE_POLL) && (newMode != SIO_MODE_INT))
	return (ERROR);
           
    oldlevel = intLock ();

    if (newMode == SIO_MODE_INT)
	{
	if (pChan->options & CLOCAL)
	    {
	    pChan->ier |= (IER_RAVIE | IER_RTOIE | IER_RLSE);
            REG(IER, pChan) = (unsigned int) pChan->ier;
	    }
	else  
	    {
	    mask = REG(MSR, pChan) & MSR_CTS;

   	    /* if the CTS is asserted enable Tx interrupt */

   	    if (mask & MSR_CTS)
		pChan->ier |= IER_TIE;
	    else
		pChan->ier &= (~IER_TIE); /* disable Tx interrupt */

	    REG(IER, pChan) = (unsigned int) pChan->ier; 
	    }	
	}
    else				/* Polled mode */
        {
        REG(IER, pChan) = (unsigned int) IER_UUE;   
	}

    pChan->channelMode = newMode;

    intUnlock (oldlevel);

    return (OK);
   }

/*******************************************************************************
*
* ixp425SioIoctl - special device control
*
* Includes commands to get/set baud rate, mode(INT,POLL), hardware options(
* parity, number of data bits), and modem control(RTS/CTS).
*
* RETURNS: OK on success, EIO on device error, ENOSYS on unsupported
*          request.
*/

LOCAL STATUS ixp425SioIoctl
    (
    IXP425_SIO_CHAN * 	pChan,		/* pointer to channel */
    int			request,	/* request code */
    int        		arg		/* some argument */
    )
    {
    FAST STATUS  status;

    status = OK;

    switch (request)
	{
	case SIO_BAUD_SET:
	    if (arg < IXP425_SIO_MIN_RATE || arg > IXP425_SIO_MAX_RATE)
		status = EIO;		/* baud rate out of range */
	    else
	        status = ixp425SioBaudSet (pChan, arg);