On 10/12/2005 02:51 PM Heikki Lindholm wrote: > Wolfgang Grandegger kirjoitti: >> On 10/11/2005 05:11 PM Fillod Stephane wrote: >> >>>Heikki Lindholm wrote: >>>[..] >>> >>>>Probably, but there are less than awesome 4xx boards around and I'd >>>>guess they might even be more likely targets than G4 based machines, >>> >>>for >>> >>>>example. Some tuning might be needed. >>> >>>How many people are using Xenomai (or Fusion) on 4xx ? >>>What are their typical sched latency ? >> >> >> Attached is the result of some latency measurements on the Ocotea eval >> board. The AMCC 440 GX is already a fast 4xx processor. Unfortunately, >> the linuxppc-2.6.10rc3 does not run on our Ebony board. Nevertheless, >> it's difficult to provide a resonable default value. Why not simply >> using 0 and it's then up to the user to provide an appropriate value >> at configuration time? > > 0? No machine is that fast. For the 32-bit ppc it might be harder to > provide a reasonable default, because of the broader scale of hardware, > but I'd guess that < 100MHz targets prefer to use a dedicated RTOS > instead of Xenomai. For the 64-bit targets, I didn't find slower than
There are a lot of 32 bit CPUs < 100 MHz running Linux and sometimes they even need a realtime extension. > 400 MHz machines and they were iSeries, which, I suppose, also aren't > prime target for Xenomai. Regardless of what default value is used, > there could be some examples provided by the config help to direct user > to the right direction. I fully agree. > What's the problem with Ebonys? I remember running at least 2.6.9 on > Ebonys (440GP) and Walnuts (405). We have linux-2.4.14-rc3 running on all AMCC eval boards (see http://www.denx.de). But the kernel supported by RTAI/Fusion, linuxppc-2.6.10rc3, does not boot on Ebony. The main problem is the missing support for U-Boot but there might be others. And it's simply not worth the effort to port it, I think. Wolfgang.
