xtmrctr.c

XINLINX公司开发板的嵌入式源代码

*		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_Stop(XTmrCtr * InstancePtr, u8 TmrCtrNumber)
{
	u32 ControlStatusReg;

	XASSERT_VOID(InstancePtr != NULL);
	XASSERT_VOID(TmrCtrNumber < XTC_DEVICE_TIMER_COUNT);
	XASSERT_VOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/*
	 * Read the current register contents
	 */
	ControlStatusReg = XTimerCtr_mReadReg(InstancePtr->BaseAddress,
					      TmrCtrNumber, XTC_TCSR_OFFSET);
	/*
	 * Disable the timer counter such that it's not running
	 */
	ControlStatusReg &= ~(XTC_CSR_ENABLE_TMR_MASK);

	/*
	 * Write out the updated value to the actual register.
	 */
	XTmrCtr_mWriteReg(InstancePtr->BaseAddress, TmrCtrNumber,
			  XTC_TCSR_OFFSET, ControlStatusReg);
}

/*****************************************************************************/
/**
*
* Get the current value of the specified timer counter.  The timer counter
* may be either incrementing or decrementing based upon the current mode of
* operation.
*
* @param	InstancePtr is a pointer to the XTmrCtr instance.
* @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	The current value for the timer counter.
*
* @note		None.
*
******************************************************************************/
u32 XTmrCtr_GetValue(XTmrCtr * InstancePtr, u8 TmrCtrNumber)
{

	XASSERT_NONVOID(InstancePtr != NULL);
	XASSERT_NONVOID(TmrCtrNumber < XTC_DEVICE_TIMER_COUNT);
	XASSERT_NONVOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	return XTimerCtr_mReadReg(InstancePtr->BaseAddress,
				  TmrCtrNumber, XTC_TCR_OFFSET);
}

/*****************************************************************************/
/**
*
* Set the reset value for the specified timer counter. This is the value
* that is loaded into the timer counter when it is reset. This value is also
* loaded when the timer counter is started.
*
* @param	InstancePtr is a pointer to the XTmrCtr instance.
* @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).
* @param	ResetValue contains the value to be used to reset the timer
*		counter.
*
* @return	None.
*
* @note		None.
*
******************************************************************************/
void XTmrCtr_SetResetValue(XTmrCtr * InstancePtr, u8 TmrCtrNumber,
			   u32 ResetValue)
{

	XASSERT_VOID(InstancePtr != NULL);
	XASSERT_VOID(TmrCtrNumber < XTC_DEVICE_TIMER_COUNT);
	XASSERT_VOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	XTmrCtr_mWriteReg(InstancePtr->BaseAddress, TmrCtrNumber,
			  XTC_TLR_OFFSET, ResetValue);
}

/*****************************************************************************/
/**
*
* Returns the timer counter value that was captured the last time the external
* capture input was asserted.
*
* @param	InstancePtr is a pointer to the XTmrCtr instance.
* @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	The current capture value for the indicated timer counter.
*
* @note		None.
*
*******************************************************************************/
u32 XTmrCtr_GetCaptureValue(XTmrCtr * InstancePtr, u8 TmrCtrNumber)
{

	XASSERT_NONVOID(InstancePtr != NULL);
	XASSERT_NONVOID(TmrCtrNumber < XTC_DEVICE_TIMER_COUNT);
	XASSERT_NONVOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	return XTimerCtr_mReadReg(InstancePtr->BaseAddress,
				  TmrCtrNumber, XTC_TLR_OFFSET);
}

/*****************************************************************************/
/**
*
* Resets the specified timer counter of the device. A reset causes the timer
* counter to set it's value to the reset value.
*
* @param	InstancePtr is a pointer to the XTmrCtr instance.
* @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_Reset(XTmrCtr * InstancePtr, u8 TmrCtrNumber)
{
	u32 CounterControlReg;

	XASSERT_VOID(InstancePtr != NULL);
	XASSERT_VOID(TmrCtrNumber < XTC_DEVICE_TIMER_COUNT);
	XASSERT_VOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/*
	 * Read current contents of the register so it won't be destroyed
	 */
	CounterControlReg = XTimerCtr_mReadReg(InstancePtr->BaseAddress,
					       TmrCtrNumber, XTC_TCSR_OFFSET);
	/*
	 * Reset the timer by toggling the reset bit in the register
	 */
	XTmrCtr_mWriteReg(InstancePtr->BaseAddress, TmrCtrNumber,
			  XTC_TCSR_OFFSET,
			  CounterControlReg | XTC_CSR_LOAD_MASK);

	XTmrCtr_mWriteReg(InstancePtr->BaseAddress, TmrCtrNumber,
			  XTC_TCSR_OFFSET, CounterControlReg);
}

/*****************************************************************************/
/**
*
* Checks if the specified timer counter of the device has expired. In capture
* mode, expired is defined as a capture occurred. In compare mode, expired is
* defined as the timer counter rolled over/under for up/down counting.
*
* When interrupts are enabled, the expiration causes an interrupt. This function
* is typically used to poll a timer counter to determine when it has expired.
*
* @param	InstancePtr is a pointer to the XTmrCtr instance.
* @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	TRUE if the timer has expired, and FALSE otherwise.
*
* @note		None.
*
******************************************************************************/
int XTmrCtr_IsExpired(XTmrCtr * InstancePtr, u8 TmrCtrNumber)
{
	u32 CounterControlReg;

	XASSERT_NONVOID(InstancePtr != NULL);
	XASSERT_NONVOID(TmrCtrNumber < XTC_DEVICE_TIMER_COUNT);
	XASSERT_NONVOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/*
	 * Check if timer is expired
	 */
	CounterControlReg = XTimerCtr_mReadReg(InstancePtr->BaseAddress,
					       TmrCtrNumber, XTC_TCSR_OFFSET);

	return ((CounterControlReg & XTC_CSR_INT_OCCURED_MASK) ==
		XTC_CSR_INT_OCCURED_MASK);
}

/*****************************************************************************
*
* Looks up the device configuration based on the unique device ID. The table
* TmrCtrConfigTable contains the configuration info for each device in the
* system.
*
* @param	DeviceId is the unique device ID to search for in the config
*		table.
*
* @return	A pointer to the configuration that matches the given device ID,
* 		or NULL if no match is found.
*
* @note		None.
*
******************************************************************************/
XTmrCtr_Config *XTmrCtr_LookupConfig(u16 DeviceId)
{
	XTmrCtr_Config *CfgPtr = NULL;
	int i;

	for (i = 0; i < XPAR_XTMRCTR_NUM_INSTANCES; i++) {
		if (XTmrCtr_ConfigTable[i].DeviceId == DeviceId) {
			CfgPtr = &XTmrCtr_ConfigTable[i];
			break;
		}
	}

	return CfgPtr;
}