Debug Message Output Issue in RTL Simulation

I am running an RTL simulation with an ARM R5 processor and trying to print debug messages from the main.c firmware.

However, the printf statement does not produce any output in the RTL simulation.

Typically, register settings in the R5 firmware are done as follows:

void main(void)
{
int i;

REGRW(0x800000, 0x0004) = 0x12;
printf("DATA Written 0x12");
}

What are the available methods to output debug messages from firmware in an RTL simulation? 

How do I print the debug message on RTL simulation?