On Tue, 2006-09-26 at 18:28 +0200, Wolfgang Grandegger wrote: > Philippe Gerum wrote: > > On Tue, 2006-09-26 at 16:56 +0200, gilles.chanteperdrix wrote: > >> ---------- Debut du message initial ----------- > >> > >> De : [EMAIL PROTECTED] > >> A : [EMAIL PROTECTED] > >> Copies : xenomai-core@gna.org > >> Date : Tue, 26 Sep 2006 16:21:18 +0200 > >> Objet : Re: [Xenomai-core] Problem with periodic timer on > >> PPC40x solved > >> > >>>> On Mon, 2006-09-25 at 22:29 +0200, Niklaus Giger wrote: > >>>>>> Am Montag, 25. September 2006 17:57 schrieb Philippe > >> Gerum: > >>>>>>> On Sun, 2006-09-24 at 23:07 +0200, Wolfgang > >> Grandegger wrote: > >>>>>>>> Niklaus Giger wrote: > >>>> <..> > >>>>>> Is the output of lines like "Xenomai: Switching > >> display-3238 to secondary > >>>>>> mode after exception #1025 from user-space at > >> 0x100033c4 (pid 3240)" > >>>>>> harmless or the result of a activated > >> CONFIG_XENO_OPT_DEBUG<..> option? > >>> A known hw issue seems to exist with the 405GP (revD), which > >> causes the > >>> ESR to be incorrectly set upon FPU emulation trap, which > >> would in turn > >>> cause the spurious exception to be relayed to the nucleus by > >> Adeos. The > >>> patch below is _not_ the final fix, but rather a way to > >> check if this > >>> message is indeed related to the FPU emulation on your > >> board. Does it > >>> silence the exception without breaking the box? > >> The FPU fault may be the result of the latency display thread > >> using the > >> FPU: on systems with emulated FPU, this looks normal. > >> > > > > This said, we should not switch the task to secondary mode, but rather > > emulate the FPU ops in primary mode. To this end, we need to make sure > > that do_mathemu() is not going to choke over this context (e.g. > > preemption count check issues over CONFIG_PREEMPT when running > > unmodified uaccess routines). We additionally need to fix the program > > check exception handler to give the math emulation code a chance to > > handle the fault before we complain loudly at the nucleus. > > OK, but in general, soft-float emulation should be used on systems > without FPU and this is even more important for real-time.
Makes sense. So maybe we should make this a more explicit and formal warning, to catch missing soft float emulation, actually. > This is a > tool chain issue. Niklaus, what tool chain are you using? > > Wolfgang. > > > -- Philippe. _______________________________________________ Xenomai-core mailing list Xenomai-core@gna.org https://mail.gna.org/listinfo/xenomai-core
