On 2/20/10, Rob Landley <r...@landley.net> wrote: > On Thursday 18 February 2010 05:21:16 Artyom Tarasenko wrote: > > 2010/2/17 Rob Landley <r...@landley.net>: > > > But it does imply that qemu is capable of decently running _something_ on > > > sparc, so the problems I'm seeing are more likely to be uClibc or > > > toolchain issues. > > > > qemu-sparc can decently run debian-40r8: gcc and all the other stuff > > seem to work. > > > > Most versions of the NetBSD boot. Some require the original OBP > > though. The only known to me version which definetely doesn't boot is > > 3.0.2. > > > > Also since the last dma fix Solaris 2.4-2.5.1 seems to be also fully > > functional. Don't have a suitable compiler to check whether it's > > working under Solaris though. > > > > Debian-40r8 should have all the necessary stuff to build the uClibc > > toolchain, right? > > So I did a network install of that Debian image into a 4 gig disk image, and > made some progress. > > First a quick bug report: qemu-system-sparc tries to set the video window to > 900 pixels vertical, but my laptop's display is only 800 pixels tall, and the > window manager trims it a bit more than that for the toolbar. The kernel > booting up seems to think the graphics window is still its original size > renders text off the bottom of it. But for some reason I can grab the window > and resize it, and when I do this the emulated kernel's frame buffer gets the > update and resizes its console to show the correct number of lines of text > for > the new size! (So my question is, why didn't it get the size right when the > window manager first resized it before I manually resized it again?) > > Anyway: yay emulated sparc debian, I installed it, got a reasonable > environment going, extracted my root filesystem image under there and > chrooted > into it... and everything worked fine. (Well, trying to run a dynamically > linked "hello world" still died with a bus error, but using the static > busybox > I could mount a tmpfs and list its contents, which I never could before.) > > My plan had been to use sparc-debian's copy of gdb to track down why the > binaries were going funky... but in that environment, they were behaving > themselves. Same binaries, built with the same toolchain, same qemu-system- > sparc, same -M and -cpu and so on... > > So I think "A-ha! Booting a different kernel! That's gotta be it!" > > The debian-sparc image is using a 2.6.18 kernel (and I'm using a 2.6.32 > kernel), but it installed the relevant .config in /boot, so I copied that out > with scp, did a "make oldconfig" up to 2.6.32 (holding down the enter key > until > it shut up), stripped out all the modules and disabled module support, put > back in CONFIG_SERIAL_SUNZILOG_CONSOLE=y and friends, procfs, sysfs, and > tmpfs > (strange things to have as modules?), and CONFIG_SQUASHFS (that's my default > root filesystem format). > > I booted the result up with init=/bin/ash, did a "mount -t tmpfs /tmp /tmp", > and then: > > / # ls -l /tmp > Illegal instruction > > It's still misbehaving. Huh. > > This is as close as I can get to the debian kernel config without adding > module > support to my images (which is unnecessary complication for what they do). I > can try an ext2 root filesystem image but I don't see how that would cause > this. > > The part I don't understand is that same busybox binary, built with the same > toolchain, worked just fine under the Debian kernel. I'd blame my toolchain, > but in a slightly different context THE BINARIES WORKED... > > I don't understand what's going wrong here. Did the kernel break on sparc > sometime between 2.6.18 and 2.6.32 and nobody noticed? Is sparc using > software emulated floating point at the kernel level and that's configured > as a > module? (Except I don't think busybox ls uses floating point...)
Sparc32 is not maintained anymore so maybe it broke at some point. There was some discussion a few years ago. > Do any sparc people understand what's going on here? My next step is to grab > a 2.6.18 kernel and try to get _that_ to work with the tweaked debian config > (and an ext2 root filesystem since squashfs wasn't merged back then and had a > format change when it was merged). But I'm mostly flailing around blind > here... I'm also trying different kernels using my .config. But already 2.6.12 hangs in ESP probe.
