If The Demmuer Is Loaded But You Still Get Physical Addresses For Some Of Your Address Space - HP MC68040 User Manual

Chapter 9: Solving Problems

If the deMMUer is loaded but you still get physical addresses for some of your address space

If the deMMUer is loaded but you still get
physical addresses for some of your address
space
Some physical accesses are normal, especially accesses to the MMU tables.
Check to see which physical memory spaces are being reverse translated by the
deMMUer. Enter the load demmuer verbose command to see a list of the physical
address spaces that will be deMMUed.
Check the setup of the MMU mapping tables. Make sure unused address spaces are
marked with invalid descriptors in the mapping tables.
Check the emulation memory map. Make sure you have allocated only the memory
spaces needed to accommodate code you are developing in your map. Make sure
you have mapped the smallest spaces that you can for the code you are developing.
Check that the MMU had the setup you wanted to analyze when you loaded the
deMMUer. If it was managing memory for some other MMU setup, break to the
monitor and issue the load demmuer command again.
Check to see if there was a context change in the MMU during execution of your
program. If there was, the content of the root pointer may have changed for
execution of the new context. The deMMUer tables were set up to reverse translate
the MMU tables under the root pointer values that existed when you entered the
load demuer command. If those root pointer values change (pointing to other
translation tables), there is no way to automatically update the deMMUer. It will
continue to provide reverse translations for the setup that existed at the time you
issued the load demmuer command. Issue the load demmuer command again.
Read "Using the deMMUer" in Chapter 10, "Using Memory Management", to
understand how the deMMUer selects the physical addresses it will translate.
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