I was trying to debug a simple LED blinking program using Keil for Tiva C series controller. It worked fine using Logic analyzer. When I tried to inspect data register of PortF (Peripherals ->System Viewer -> GPIO -> GPIOF) it was not updating the content. All the other registers associated with the PortF are getting updated. I am using Keil 4.74 and TM4C123GH6PM microcontroller.
Sorry for the late reply. The "Periodic Window Update" is checked in the "View" menu. Still it is not updating. I was doing a course on edX (www.edx.org/.../embedded-systems-shape-world-utaustinx-ut-6-03x) and I noticed that when I include a custom dll called LaunchPadDLL(which was written by the author of the course) in the debug options then it was updating the data register properly. So I believe there are some options in uVision4 to update all the registers(especially the data registers) in the System Viewer.