Configuring EPI for GPIO mode

I tried configuring EPI for GPIO mode. EPI is supposed to generate interrupt at a rate of 600KHz. Instead, EPI generates interrupt at the rate of 300KHz. Attached is the code. Please let me know the issue.

Thanks & regards

Thangavel.P

*
 * main.c
 */


#define EPI_PORT 0xA0000000
#include "cdt_customdatatypes.h"
#include <stdbool.h>
#include <stdint.h>
#include "inc/hw_ints.h"
#include "driverlib/pin_map.h"
#include "driverlib/rom.h"
#include "driverlib/rom_map.h"
#include "inc/hw_epi.h"
#include "inc/hw_memmap.h"
#include "inc/hw_types.h"
#include "inc/hw_gpio.h"
#include "driverlib/epi.h"
#include "driverlib/gpio.h"
#include "driverlib/sysctl.h"
#include "driverlib/udma.h"
#include "ESM.h"
#pragma DATA_ALIGN(pui8ControlTable, 1024)
uint8_t pui8ControlTable[1024];
U16 V_ESMRPM_U16R = 200/*Value for 10,000 RPM*/;
U32 g_ui32MemXferCount =0;


int main(void)
{
	U32 v_SysClock_u32r ;
	U32 v_USBPLLRate_u32r;
	U32 v_temp_u32r;

	//
	// Set the system clock to run at 120MHz from the PLL.
	//
	v_SysClock_u32r = MAP_SysCtlClockFreqSet((SYSCTL_XTAL_25MHZ |
										   SYSCTL_OSC_MAIN | SYSCTL_USE_PLL |
										   SYSCTL_CFG_VCO_480), 120000000);
	//
	// Enable all the GPIO peripherals.
	//
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOC);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOD);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOG);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOH);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOJ);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOK);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOL);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOM);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPION);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOP);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOQ);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOR);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOS);
	ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOT);

	ROM_GPIOPinTypeGPIOOutput(GPIO_PORTM_BASE, (GPIO_PIN_7 | GPIO_PIN_6 | GPIO_PIN_5 | GPIO_PIN_2 | GPIO_PIN_1 | GPIO_PIN_0));
	ROM_GPIOPinWrite(GPIO_PORTM_BASE, GPIO_PIN_0, 0);
	ROM_GPIOPinWrite(GPIO_PORTM_BASE, GPIO_PIN_2, 1);


	//
	// Enable the EPI module.
	//
	SysCtlPeripheralEnable(SYSCTL_PERIPH_EPI0);
	//
	// Wait for the EPI module to be ready.
	//
	while(!SysCtlPeripheralReady(SYSCTL_PERIPH_EPI0));
	//
	// Configure the GPIO Pins
	//
	GPIOPinConfigure(GPIO_PH0_EPI0S0);    	// PH0 -> Crank
	GPIOPinConfigure(GPIO_PH1_EPI0S1);    	// PH1 -> Cam 1
	GPIOPinConfigure(GPIO_PH2_EPI0S2);		// PH2 -> Cam 2
	GPIOPinConfigure(GPIO_PH3_EPI0S3);     	// PH3 -> Cam 3
	GPIOPinConfigure(GPIO_PC7_EPI0S4);     	// PC7 -> Cam 4
	GPIOPinTypeEPI(GPIO_PORTC_BASE, 0x80);
	GPIOPinTypeEPI(GPIO_PORTH_BASE, 0x0F);
	//
	// Enable the INTDIV
	//
	HWREG(EPI0_BASE+EPI_O_CFG) = 0x110;
	//
	// Set the EPI divider.
	//
	EPIDividerSet(EPI0_BASE, 200);

	// Set EPI Mode
	EPIConfigGPModeSet(EPI0_BASE, EPI_GPMODE_CLKPIN | EPI_GPMODE_ASIZE_NONE | EPI_GPMODE_DSIZE_8, 0, 0);
	//
	// Set the address map.
	//
	EPIAddressMapSet(EPI0_BASE, EPI_ADDR_RAM_SIZE_64KB | EPI_ADDR_RAM_BASE_6);

	//Address map to 0xA000.0000
	EPIAddressMapSet(EPI0_BASE, EPI_ADDR_PER_BASE_A | EPI_ADDR_PER_BASE_NONE);
	//
	// Enable the WFIFO Trigger Level
	//
	EPIFIFOConfig(EPI0_BASE, EPI_FIFO_CONFIG_TX_1_4);

	//EPIDMATxCount(EPI0_BASE, 900);
	//
	// Enable the EPI interrupts
	//
	EPIIntEnable(EPI0_BASE, EPI_INT_TXREQ);

	while(1)
	{

		if((EPIIntStatus(EPI0_BASE, 1) & EPI_INT_TXREQ) == EPI_INT_TXREQ)
		{
			v_USBPLLRate_u32r++;
			if((v_USBPLLRate_u32r&0x01) == 0x01)
			{
				HWREGH(EPI_PORT) = 0xFF;
				ROM_GPIOPinWrite(GPIO_PORTM_BASE, GPIO_PIN_0, 1);
			}

			else
			{
				HWREGH(EPI_PORT) = 0;
				ROM_GPIOPinWrite(GPIO_PORTM_BASE, GPIO_PIN_0, 0);
			}

		}

	}
	return 0;
}