> Iam trying to bring up a custom board > with RM5231A MIPS processor and IT8172 > companion chip. Right now i have an > issue related to running Linux 2.4.25 on > MIPS with cache enabled. > When i run the kernel with CPU Cache > enabled, i get the following error > messages. > A. "Unhandled kernel unaligned access or > invalid instruction in > unaligned.c::emulate_load_store_insn, > line 493:" > B. "Reserved instruction in kernel code > in traps.c::do_ri, line 663:" > C. "Unable to handle kernel paging > request at virtual address 00000000 > > These errors happen when i run fsck, vi > or a simple du command. > When i trun on the "Run uncached" > option these errors disapper. > > I do not know where to start debugging. > Can any one tell me what could be the > problem when the cache is turned on. That CPU and coprocessor are/were supported in 2.4 so in general, the kernel "should" run. If you have access to an off the shelf reference board with that CPU and system processor, start there and see if the kernel runs on that board. If it does not, you may be looking at a kernel issue. If the kernel runs on the reference board, then your issue is most likely a hardware problem with your board. If you don't have access to a reference board, then you'll be trying to figure out if this is a hardware or kernel problem. I'm guessing it's hardware but hopefully not. Hook in kgdb and try to reproduce the problem with the most simple test you can find that causes the crash. Examine the point of failure and try to make sense of it to figure out if it's kernel or hardware related. Of course I assume you've already ran at least basic memory tests on the board and that much passes. If not, then start there. Pete
