>> >>> + /* Switch to z/Architecture mode (64-bit) */ >>> + slr %r0, %r0 # set cpuid to zero >>> + lhi %r1, 2 # mode 2 = esame >>> + sigp %r1, %r0, 0x12 # sigp set arch >>> + bras %r13,0f >>> + .fill 16,4,0x0 >>> +0: lmh %r0,%r15,0(%r13) # clear high-order half of gprs >> >> This is just what the kernel does. The ".fill" part is confusing at >> first, but it is just the data loaded into the high-order halfs (all 0s) >> >> (I was told mixing code and data is bad practice, but for some reason >> people in Linux decided to do it like that (maybe because of some >> relocation thingy? or because of instruction set restrictions?)) > > Honestly I wouldn't even have considered clearing if I haven't seen it > in the kernel. I could define a zero area at the end of the file or do > an lm targeting the cleared bss right before jumping into setup. Or we > could do 16 xc register to register :) Or we'll just stick to what the kernel did here ... at least that way we can be pretty sure we don't make mistakes. Whatever you prefer ;) > >> >> Should we introduce defines for SIGPs? We might have more once we >> support multiple CPUs eiher way. > > We also have sigp stop so why not. > How about making the indent patch a cleanup patch and adding all > commands there? Sure, fine with me! -- Thanks, David / dhildenb
