TM4C1294KCPDT Hibernate 模块使能时间太久问题

问题描述：系统上电打开了看门狗定时器1（看门狗定时时间为0.1S）代码中有使能TM4C1294KCPDT的Hibernate模块，在一批次产品中，有部分产品会出现CPU反复重启。后面经过分析发现出问题CPU的HibernateEnableExpClk中使能时钟不成功，导致一直等待从而看门狗超时，所以必须加长看门狗的时间到接近2S，有问题的才可以启动；但是正常批次的产品看门狗时间定在0.1S可以正常启动，请问这是什么原因导致的呢？相关代码如下

//*****************************************************************************
//
//! Enables the Hibernation module for operation.
//!
//! \param ui32HibClk is the rate of the clock supplied to the Hibernation
//! module.
//!
//! This function enables the Hibernation module for operation.  This function
//! should be called before any of the Hibernation module features are used.
//!
//! The peripheral clock is the same as the processor clock.  This value is
//! returned by SysCtlClockGet(), or it can be explicitly hard-coded if it is
//! constant and known (to save the code/execution overhead of a call to
//! SysCtlClockGet()).
//!
//! \return None.
//
//*****************************************************************************
void
HibernateEnableExpClk(uint32_t ui32HibClk)
{
	
		int i;
    //
    // Turn on the clock enable bit.
    //
    HWREG(HIB_CTL) |= HIB_CTL_CLK32EN;
		while(!(HWREG(HIB_CTL) & HIB_CTL_CLK32EN))
    {
			i++;
			if(i>=10000)
			{
				Consol_Printf("Clock Set Failed..\n");
			}		
		}
    //
    // Wait for write complete following register load (above).
    //
    _HibernateWriteComplete();
}

//*****************************************************************************
//
//! \internal
//!
//! Polls until the write complete (WRC) bit in the hibernate control register
//! is set.
//!
//! \param None.
//!
//! The Hibernation module provides an indication when any write is completed.
//! This mechanism is used to pace writes to the module.  This function merely
//! polls this bit and returns as soon as it is set.  At this point, it is safe
//! to perform another write to the module.
//!
//! \return None.
//
//*****************************************************************************
#include "bsp_consol.h"
static void
_HibernateWriteComplete(void)
{
	static int i = 0;
    //
    // Spin until the write complete bit is set.
    //
    while(!(HWREG(HIB_CTL) & HIB_CTL_WRC))
    {	
    }
}