Disclaimer: As nothing really interesting has been happening lately, be forewarned that this entry will be somewhat dry and generally boring, even if for some reason you _are_ interested in the state of Linux/SH-2 support.
Lots of SH-2 hacking lately, quite exhausting, though still quite fun. The VBR semantics are completely different in relation to the SH-3/4, so this buys entry.S a much needed overhaul. Unfortunately this also required some changes in semantics, at least on the SH-2 side for the general-purpose exception handling code -- though this is all quite hacky already, especially given the number of different registers and register names, etc.
Another minor nuisance, gcc sanely labels things like saving off ssr as an SH-3 and up instruction, but binutils subsequently defaults to accepting virtually anything as valid. binutils CVS now seems to properly support a processor family flag that clearly defines this, so that should be dealt with relatively well once I get finished hacking that.. this will be an interesting contrast to gcc flags by ABI level, so hopefully that will all work out cleanly. Between that and the latest -fno-zero-initialized-in-bss mess with 3.3, I definitely hope we won't need more stupid gcc/binutils version specific checks for the kernel build, as these are already starting to add up..
Additionally, the fixed references to arch/foo/kernel/vmlinux.lds.S in the top-level kernel Makefile are truly annoying. This now forces anyone who wants to use multiple ld scripts to either make a wrapper script with ifdef abuse, or do gross symlinking hacks at build time. This is certainly a disappointing step back in comparison to the 2.4 behavior..
Back to the SH-2 issue, it should be a lot easier to identify what still needs to be done (other then things like the system call interface, which still needs cleanup for things like TRA referencing, INTEVT/EXPEVT stuff I just finished) once the aforementioned binutils issues are out of the way. It's quite bothersome to identify problem spots when the assembler will knowingly accept accesses to things like different register banks and ssr/spc, etc. even when these don't actually exist on the SH-2.. though I'm sure there will be quite a few. At least now with the exception vector, early SCI console, XIP, etc. out of the way, we should be set to actually start debugging on live silicon.. Now the only other trick is getting the page_alloc2 stuff updated and merged, and getting the overly pesky inode and dentry cache hast tables reduced in size -- there's not a whole lot of room when you've only got 512KiB of RAM to work with..
Also got some 7760 IPR patches sitting in my home directory, this is pretty much the last remaining portion of the 7760 backend that needs to go in (I did the exception vector / sh-sci / etc. stuff previously). So this is definitely good news, even though it reminds me that I still need to get the 7040/7044/7045/etc. stuff figured out and written..
Lastly, also got some uClibc hacking done. Some relatively uneventful sh64 syscall updates to satisfy current busybox, etc. Just finished off the pthreads work, so now we should be good to go for static pthreads.. that still leaves the ldso work, but that can wait for another day (particularly as it's rather mind numbing). After that, we should be able to start doing sh64 builds under buildroot, should be fun.