To workaround a hardware erratum on the H3 SoC, we use an MMIO register
based assembly routine to dump the SID registers, if needed. This is
hard-coded to read the first four 32-bit words of the SID fuses.
For the sid-dump command we need to access any arbitrary regions of the
fuses, so extend the routine to take a start and an end address to dump.
This changes the assembly source in the thunks/ directory:
- We load the start address into r1, instead of zeroing it. The start
address is put right after the SIO MMIO base address, at the end of
the code.
- When storing the read value into the result buffer, we automatically
increase the pointer register (r3), instead of adding the offset
address, since this is now no longer zero based.
- To check for the end, we read the end pointer (stored at the end of
the code, right after the offset), and compare against that instead of
the hardcoded value of 16.
This assembly file was put through the thunks Makefile, and the resulting
content was copied from thunks/sid_read_root.h into fel_lib.c.
For now we are still putting the constant values of 0 and 16 in, but
this time from the C code.
Signed-off-by: Andre Przywara <osp@andrep.de>
