On Mon, Aug 23, 2004 at 03:22:24PM +0200, Thierry Godefroy wrote: > > I'm quite upset !... > > I just discovered that my Q60 was fitted with a buggy 68060 ! > Yes, a pre-1996 mask 060 (1G65V mask), while my Q60 was built > as bought in 2001 !!!... This makes me wonder how many among > the Q60s have that same buggy processor fitted... > > I discovered this because Linux v2.4 got a recent fix for the > I14 errata of these buggy processor, and logs the activation > of the fix when the kernel boots.
didn't look at it yet, does Linux actually test whether its an affected CPU, or just disable that optimisation? > This fix consists in setting > the bit 5 in the PCR (Processor Control Register), which > disables one of the optimisations of the 060. But there are no > less than 21 bugs in the maskset of my 060 !!!... No wonder why > I get weird results each time I try to modify SMSQ/E and QLib_run > in order make them work properly in copyback mode (currently, > QLiberated programs hang/crash/loop randomly when copyback is > enabled). I did once go through all the horrible 68060 errata and it doesn't appear SMSQ or QDOS would trigger any of these. > For the ones interested in the details about these bugs, they > will find the 68060 device errata document here: > http://www.freescale.com/files/32bit/doc/no_sub_type/MC68060DE.pdf > > Anyway... > > I'm now in search for a bug-less and full blown 60MHz 68060 > (0E41J mask ONLY)... does that exist? I think it exists only on paper or as RC/LC version :(( If you look at 68040 and 68060 errata lists you would be surprised that those CPUs ever worked, but apparently all but one of those bugs can be "managed" by OS software without significant performance degradation. Richard