xps2.c

基于FPGA的防火墙系统设计.rar

/* $Id: xps2.c,v 1.1 2006/02/16 23:45:09 moleres Exp $ */
/*****************************************************************************
*
*       XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS"
*       AS A COURTESY TO YOU, SOLELY FOR USE IN DEVELOPING PROGRAMS AND
*       SOLUTIONS FOR XILINX DEVICES.  BY PROVIDING THIS DESIGN, CODE,
*       OR INFORMATION AS ONE POSSIBLE IMPLEMENTATION OF THIS FEATURE,
*       APPLICATION OR STANDARD, XILINX IS MAKING NO REPRESENTATION
*       THAT THIS IMPLEMENTATION IS FREE FROM ANY CLAIMS OF INFRINGEMENT,
*       AND YOU ARE RESPONSIBLE FOR OBTAINING ANY RIGHTS YOU MAY REQUIRE
*       FOR YOUR IMPLEMENTATION.  XILINX EXPRESSLY DISCLAIMS ANY
*       WARRANTY WHATSOEVER WITH RESPECT TO THE ADEQUACY OF THE
*       IMPLEMENTATION, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OR
*       REPRESENTATIONS THAT THIS IMPLEMENTATION IS FREE FROM CLAIMS OF
*       INFRINGEMENT, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
*       FOR A PARTICULAR PURPOSE.
*
*       (c) Copyright 2002-2005 Xilinx Inc.
*       All rights reserved.
*
*****************************************************************************/
/****************************************************************************/
/**
*
* @file xps2.c
*
* This file contains the required functions for the PS/2 driver.
* Refer to the header file xps2.h for more detailed information.
*
* <pre>
* MODIFICATION HISTORY:
*
* Ver   Who  Date     Changes
* ----- ---- -------- -----------------------------------------------
* 1.00a ch   06/18/02 First release
* 1.00a rmm  05/14/03 Fixed diab compiler warnings relating to asserts.
* 1.01a jvb  12/13/05 I changed Initialize() into CfgInitialize(), and made
*                     CfgInitialize() take a pointer to a config structure
*                     instead of a device id. I moved Initialize() into
*                     xgpio_sinit.c, and had Initialize() call CfgInitialize()
*                     after it retrieved the config structure using the device
*                     id. I removed include of xparameters.h along with any
*                     dependencies on xparameters.h and the _g.c config table.
*
* </pre>
*
*****************************************************************************/

/***************************** Include Files ********************************/

#include "xstatus.h"
#include "xps2.h"
#include "xps2_i.h"
#include "xps2_l.h"
#include "xio.h"

/************************** Constant Definitions ****************************/

/**************************** Type Definitions ******************************/

/***************** Macros (Inline Functions) Definitions ********************/

/************************** Variable Definitions ****************************/

/************************** Function Prototypes *****************************/

static void XPs2_StubHandler(void *CallBackRef, Xuint32 Event,
                             unsigned int ByteCount);

/****************************************************************************/
/**
*
* Initializes a specific PS/2 instance such that it is ready to be used.
* The default operating mode of the driver is polled mode.
*
* @param InstancePtr is a pointer to the XPs2 instance to be worked on.
* @param Config is a reference to a structure containing information about
*        a specific PS2 device. This function initializes an InstancePtr object
*        for a specific device specified by the contents of Config. This
*        function can initialize multiple instance objects with the use of
*        multiple calls giving different Config information on each call.
* @param EffectiveAddr is the device base address in the virtual memory address
*        space. The caller is responsible for keeping the address mapping
*        from EffectiveAddr to the device physical base address unchanged
*        once this function is invoked. Unexpected errors may occur if the
*        address mapping changes after this function is called. If address
*        translation is not used, use Config->BaseAddress for this parameters,
*        passing the physical address instead.
*
* @return
*
* - XST_SUCCESS if initialization was successful
*
* @note
*
* The Config pointer argument is not used by this function, but is provided
* to keep the function signature consistent with other drivers.
*
*****************************************************************************/
XStatus XPs2_CfgInitialize(XPs2 *InstancePtr, XPs2_Config *Config,
                           Xuint32 EffectiveAddr)
{
    /*
     * Assert validates the input arguments
     */
    XASSERT_NONVOID(InstancePtr != XNULL);

    /*
     * Setup the data that is from the configuration information
     */
    InstancePtr->BaseAddress = EffectiveAddr;

    /*
     * Initialize the instance data to some default values and setup a default
     * handler
     */
    InstancePtr->Handler = XPs2_StubHandler;

    InstancePtr->SendBuffer.NextBytePtr = XNULL;
    InstancePtr->SendBuffer.RemainingBytes = 0;
    InstancePtr->SendBuffer.RequestedBytes = 0;

    InstancePtr->ReceiveBuffer.NextBytePtr = XNULL;
    InstancePtr->ReceiveBuffer.RemainingBytes = 0;
    InstancePtr->ReceiveBuffer.RequestedBytes = 0;

    /*
     * Reset the PS/2 Hardware
     */
    XPs2_mReset(InstancePtr->BaseAddress);

    /*
     * Disable all PS/2 interrupts
     */
    XPs2_mDisableIntr(InstancePtr->BaseAddress, XPS2_INT_ALL);

    /*
     * Indicate the instance is now ready to use, initialized without error
     */
    InstancePtr->IsReady = XCOMPONENT_IS_READY;

    return XST_SUCCESS;
}

/****************************************************************************/
/**
*
* This functions sends the specified buffer of data to the PS/2 port in either
* polled or interrupt driven modes. This function is non-blocking such that it
* will return before the data has been sent thorugh PS/2. If the port is busy
* sending data, it will return and indicate zero bytes were sent.
*
* In a polled mode, this function will only send 1 byte which is as much data
* as the transmitter can buffer. The application may need to call it
* repeatedly to send a buffer.
*
* In interrupt mode, this function will start sending the specified buffer and
* then the interrupt handler of the driver will continue sending data until the
* buffer has been sent. A callback function, as specified by the application,
* will be called to indicate the completion of sending the buffer.
*
* @param    InstancePtr is a pointer to the XPs2 instance to be worked on.
* @param    BufferPtr is pointer to a buffer of data to be sent.
* @param    NumBytes contains the number of bytes to be sent. A value of zero
*           will stop a previous send operation that is in progress in interrupt
*           mode. Any data that was already put into the transmit FIFO will be
*           sent.
*
* @return
*
* The number of bytes actually sent.
*
* @note
*
* The number of bytes is not asserted so that this function may be called with
* a value of zero to stop an operation that is already in progress.
* <br><br>
* This function modifies shared data such that there may be a need for mutual
* exclusion in a multithreaded environment
*
*****************************************************************************/
unsigned int XPs2_Send(XPs2 *InstancePtr, Xuint8 *BufferPtr,
                       unsigned int NumBytes)
{
    unsigned int BytesSent;

    /*
     * Assert validates the input arguments
     */
    XASSERT_NONVOID(InstancePtr != XNULL);
    XASSERT_NONVOID(BufferPtr != XNULL);
    XASSERT_NONVOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

    /*
     * Enter a critical region by disabling the PS/2 transmit interrupts to
     * allow this call to stop a previous operation that may be interrupt
     * driven, only stop the transmit interrupt since this critical region is
     * not really exited in the normal manner
     */
    XPs2_mDisableIntr(InstancePtr->BaseAddress, XPS2_INT_TX_ALL);

    /*
     * Setup the specified buffer to be sent by setting the instance
     * variables so it can be sent with polled or interrupt mode
     */
    InstancePtr->SendBuffer.RequestedBytes = NumBytes;
    InstancePtr->SendBuffer.RemainingBytes = NumBytes;
    InstancePtr->SendBuffer.NextBytePtr = BufferPtr;

    /*
     * Send the buffer and return the number of bytes sent
     */
    BytesSent = XPs2_SendBuffer(InstancePtr);

    /*
     * The critical region is not exited in this function because of the way
     * the transmit interrupts work. The other function called enables the
     * transmit interrupt such that this function can't restore a value to the
     * interrupt enable register and does not need to exit the critical region
     */
    return BytesSent;
}


/****************************************************************************/
/**
*
* This function will attempt to receive a specified number of bytes of data
* from PS/2 and store it into the specified buffer. This function is