/* $Id: xtmrctr.c,v 1.9 2002/06/14 21:59:35 linnj 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 Xilinx Inc.*       All rights reserved.*******************************************************************************//*****************************************************************************//**** @file xtmrctr.c** Contains required functions for the XTmrCtr driver.** <pre>* MODIFICATION HISTORY:** Ver   Who  Date     Changes* ----- ---- -------- -----------------------------------------------* 1.00a ecm  08/16/01 First release* 1.00b jhl  02/21/02 Repartitioned the driver for smaller files* </pre>*******************************************************************************//***************************** Include Files *********************************/#include "xbasic_types.h"#include "xstatus.h"#include "xparameters.h"#include "xtmrctr.h"#include "xtmrctr_i.h"/************************** Constant Definitions *****************************//**************************** Type Definitions *******************************//***************** Macros (Inline Functions) Definitions *********************//************************** Function Prototypes ******************************//************************** Variable Definitions *****************************//*****************************************************************************//**** Initializes a specific timer/counter instance/driver. Initialize fields of* the XTmrCtr structure, then reset the timer/counter** @param    InstancePtr is a pointer to the XTmrCtr instance to be worked on.* @param    DeviceId is the unique id of the device controlled by this XTmrCtr*           component.  Passing in a device id associates the generic XTmrCtr*           component to a specific device, as chosen by the caller or*           application developer.** @return**   - XST_SUCCESS if initialization was successful*   - XST_DEVICE_IS_STARTED if the device has already been started*   - XST_DEVICE_NOT_FOUND if the device doesn't exist** @note** None.*******************************************************************************/XStatus XTmrCtr_Initialize(XTmrCtr *InstancePtr, Xuint16 DeviceId){    XTmrCtr_Config *TmrCtrConfigPtr;    int TmrCtrNumber;    Xuint32 StatusReg;    XASSERT_NONVOID(InstancePtr != XNULL);    /*     * Lookup the device configuration in the temporary CROM table. Use this     * configuration info down below when initializing this component.     */    TmrCtrConfigPtr = XTmrCtr_LookupConfig(DeviceId);    if (TmrCtrConfigPtr == (XTmrCtr_Config *)XNULL)    {        return XST_DEVICE_NOT_FOUND;    }    /* Check each of the timer counters of the device, if any are already     * running, then the device should not be initialized. This allows the user     * to stop the device and reinitialize, but prevents a user from     * inadvertently initializing.     */    for (TmrCtrNumber = 0; TmrCtrNumber < XTC_DEVICE_TIMER_COUNT; TmrCtrNumber++)    {        /*         * read the current register contents and check if the timer counter         * is started and running, note that the register read is not using         * the base address in the instance so this is not destructive if         * the timer counter is already started         */        StatusReg = XTimerCtr_mReadReg(TmrCtrConfigPtr->BaseAddress,                                      TmrCtrNumber, XTC_TCSR_OFFSET);        if (StatusReg & XTC_CSR_ENABLE_TMR_MASK)        {            return XST_DEVICE_IS_STARTED;        }    }    /*     * Set some default values, including setting the callback     * handlers to stubs.     */    InstancePtr->BaseAddress = TmrCtrConfigPtr->BaseAddress;    InstancePtr->Handler = XNULL;    InstancePtr->CallBackRef = XNULL;    /*     * Clear the statistics for this driver     */    InstancePtr->Stats.Interrupts = 0;    /* Initialize the registers of each timer/counter in the device */    for (TmrCtrNumber = 0; TmrCtrNumber < XTC_DEVICE_TIMER_COUNT; TmrCtrNumber++)    {        /*         * set the Compare register to 0         */        XTmrCtr_mWriteReg(InstancePtr->BaseAddress, TmrCtrNumber,                           XTC_TLR_OFFSET, 0);        /*         * reset the timer and the interrupt, the reset bit will need to         * be cleared after this         */        XTmrCtr_mWriteReg(InstancePtr->BaseAddress, TmrCtrNumber,                           XTC_TCSR_OFFSET,                           XTC_CSR_INT_OCCURED_MASK | XTC_CSR_LOAD_MASK);        /*         * set the control/status register to complete initialization by         * clearing the reset bit which was just set         */        XTmrCtr_mWriteReg(InstancePtr->BaseAddress, TmrCtrNumber,                           XTC_TCSR_OFFSET, 0);    }    /*     * indicate the instance is ready to use, successfully initialized     */    InstancePtr->IsReady = XCOMPONENT_IS_READY;    return XST_SUCCESS;}/*****************************************************************************//**** Starts the specified timer counter of the device such that it starts running.* The timer counter is reset before it is started and the reset value is* loaded into the timer counter.** If interrupt mode is specified in the options, it is necessary for the caller* to connect the interrupt handler of the timer/counter to the interrupt source,* typically an interrupt controller, and enable the interrupt within the* interrupt controller.** @param    InstancePtr is a pointer to the XTmrCtr instance to be worked on.* @param    TmrCtrNumber is the timer counter of the device to operate on.*           Each device may contain multiple timer counters. The timer number*           is a zero based number with a range of*           0 - (XTC_DEVICE_TIMER_COUNT - 1).** @return** None.** @note** None.*******************************************************************************/void XTmrCtr_Start(XTmrCtr *InstancePtr, Xuint8 TmrCtrNumber){    Xuint32 ControlStatusReg;    XASSERT_VOID(InstancePtr != XNULL);    XASSERT_VOID(TmrCtrNumber < XTC_DEVICE_TIMER_COUNT);    XASSERT_VOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);    /*     * read the current register contents such that only the necessary bits     * of the register are modified in the following operations     */    ControlStatusReg = XTimerCtr_mReadReg(InstancePtr->BaseAddress,                                         TmrCtrNumber, XTC_TCSR_OFFSET);    /*     * reset the timer counter such that it reloads from the compare register     * and the interrupt is cleared simultaneously, the interrupt can only be     * cleared after reset such that the interrupt condition is cleared     */    XTmrCtr_mWriteReg(InstancePtr->BaseAddress, TmrCtrNumber,                       XTC_TCSR_OFFSET,                       XTC_CSR_LOAD_MASK | XTC_CSR_INT_OCCURED_MASK);    /*     * remove the reset condition such that the timer counter starts running     * with the value loaded from the compare register     */    XTmrCtr_mWriteReg(InstancePtr->BaseAddress, TmrCtrNumber,                       XTC_TCSR_OFFSET,                       ControlStatusReg | XTC_CSR_ENABLE_TMR_MASK);}/*****************************************************************************//**** Stops the timer counter by disabling it.** It is the callers' responsibility to disconnect the interrupt handler of the* timer_counter from the interrupt source, typically an interrupt controller,* and disable the interrupt within the interrupt controller.** @param    InstancePtr is a pointer to the XTmrCtr instance to be worked on.* @param    TmrCtrNumber is the timer counter of the device to operate on.*           Each device may contain multiple timer counters. The timer number*           is a zero based number with a range of*           0 - (XTC_DEVICE_TIMER_COUNT - 1).** @return** None.** @note** None.*