static device mappings.
This SoC relied heavily on the fact that all devices were static-mapped
at a fixed address, and it (rather bogusly) used bus_space read and write
calls passing hard-coded virtual addresses instead of proper bus handles,
relying on the fact that the virtual addresses of the mappings were known
at compile time, and relying on the implementation details of arm
bus_space never changing. All such usage was replaced with calls to
bus_space_map() to obtain a proper bus handle for the read/write calls.
This required adjusting some of the #define values that map out hardware
registers, and some of them were renamed in the process to make it clear
which were defining absolute physical addresses and which were defining
offsets. (The ones that just define offsets don't appear to be referenced
and probably serve no value other than perhaps documentation.)
shifts into the sign bit. Instead use (1U << 31) which gets the
expected result.
This fix is not ideal as it assumes a 32 bit int, but does fix the issue
for most cases.
A similar change was made in OpenBSD.
Discussed with: -arch, rdivacky
Reviewed by: cperciva