After receiving my JTAG emulator, I did some preliminary testing of the GPIO maximum toggle speed (the time it takes to change from a high to a low). When running through the Linux kernel, I was getting a maximum rate of around 8 KHz. or less. With direct access to the GPIO registers, I am able to get a maximum rate of just a little over 1.5 MHz. I am also able to write all the bits at one time instead of one bit at a time. This results in virtually NO delay between each bit. SO... it looks like I will be able to meet my requirements by using "bare metal" programming.
After working in electronics design for almost 41 years, and some of the last few years of that doing embedded microprocessor programming and design, I have again gotten the bug to do some playing around with microprocessors.