pc/dat.h		1991/0612		Created.
		1991/0614
		1991/0702
		1991/0703
		1991/0706
		1991/0711
		1991/0716
		1991/0717
		1991/0718
		1991/0720
		1991/0801
		1991/0809
		1991/0905
		1991/0906
		1991/0916
		1991/1004
		1991/1107
		1991/1112
		1991/1210
		1991/1211
		1992/0208
		1992/0209
		1992/0228
		1992/0622
		1992/0625
		1992/06271
		1992/0725
		1992/0806
		1992/0807
		1992/0902		Replace machtype with mousetype and pmutype.
		1992/0903		Fiddle with PMU* and Mouse* configurations. Add Reset*.
		1992/0904		Remove PMU*, Mouse*, Reset* configuration info.
		1992/0918		Add machtype.
		1992/0923		Add PCArch. Comment edit. Remove machtype.
		1992/1105		In conf: remove ipif, ip, frag, ldepth, maxx, maxy.
		1993/0206		Remove conf.arp.
		1993/0915		Import from Plan 9 to Brazil.
		1993/1013		Add Notsave, cpuflag.
		1993/1201		Add Mach.otlbfault.
		1993/1204		Add Mach.runq.
		1993/1214		Remove Mach.runq; add hiq and loq. Remove Mach.otlbfault.
		1994/0311		In Mach: add cbin, cbout, cbend, calls.
		1994/0322		Remove Lock.pc; add Lock.sr. Add conf.ialloc.
		1994/0331		In Mach: define cbin, cbout, cbend, calls as Callbk* instead of void*.
		1994/0503		Add conf.pipeqsize.
		1994/0508		In Mach: remove cbin, cbout, cbend, calls.
		1994/0520		Remove flipD.
		1994/0607		Add Mach.filaddr.
		1994/0612		Remove AOUT_MAGIC; add EXEC_MAGIC.
		1994/0621		Remove EXEC_MAGIC; add AOUT_MAGIC.
		1994/0728		Remove Mach.hiq and Mach.loq.
		1994/0813		Add crasharea.
		1994/0814		Remove crasharea.
		1994/0823		Add ISAConf.freq.
		1994/0908		Add Target.
		1995/0223		Comment ISAConf and Target.
		1995/0225		Add PCMmap.
		1995/0517		Add PCIcfg.
		1995/0803		Add ISAConf.dma.
		1995/0920		Add parsed plan9.ini options to ISAConf.
		1995/1009		Add Lock.pc.
		1995/1030		Add Lock.pid.
		1996/0210		Add Target.rendez.
		1996/0511		Add Lock.pri.
		1996/0523		Remove Lock.pri
		1997/0327		PC architecture cleanup + initial SMP support.
		1997/1101		Change pdb to ulong*.
		1998/0115		Add Mach.spuriousintr, Mach.lastintr.
		1998/0401		Add copy of MTRR registers to Mach.
		1998/0604		Debugging: save Proc* in Lock instead of pid.
		1998/0605		Alphabetize Proc typedef.
		1998/0606		Remove pri from Lock, add fairness to Proc.
		1998/0710		Add fastclock function pointer to Arch.
		1998/0716		Add clockstart to Mach.
		1998/0717		In Mach: remove clockstart, add fastclock.
		1998/0725		Move fastclock; add flushmmu.
		1998/0825		Bug fix: print format. (Change lastintr to int to match print statements in pc/trap.c.)
		1998/0910		New structure Vctl; remove Irq, Irqctl, and SCSI Target.
		1998/0916		Add nswppo to conf.
		1999/0131		Add cpuhz to Mach.
		1999/0701		Add intrts to Mach.
		1999/0810		Add glare to Lock.
		1999/0811		Remove glare from Lock.
		2000/0623		Add Cycintr.
		2000/1018		Use NGDT for gdt array in Mach.
		2000/1106		Add inclockintr to Mach.
		2000/1118		Add typedef PCMslot.
		2001/0121		Increase ISAOPTLEN.
		2001/0527		Add nuart to conf. Change ISAConf.type and ISAconf.opt to allocated buffers.
		2001/0731		Add #define MAXSYSARG.
		2001/0819		Comment edit.
		2001/0905		Add intrvecno and intrdisable to Arch. Add port_t (sic) and DevConf.
		2002/0109		Whitespace edit.
		2002/0221		Bug fix?: use vlong for cpuhz.
		2002/0315		Add edfwaiting to Lock. Suspect formatting edit.
		2002/0330		Remove edfwaiting from Lock.
		2002/0404		Move Cycintr typedef] up.
		2002/0405		Rename Cycintr to Timer. In Mach, add havetsc and rename fastclock to lasttsc.
		2002/0410		Remove Timer. Add Mach.apictimerlock. Remove Mach.lasttsc. Add Arch.timerset.
		2002/0412		Comment edit. Formatting edit. Add havepge to Mach.
		2002/0415		In Mach: change cpuhz to uvlong, add tscticks, tscoff.
		2002/0420		Add ilockdepth to mach.
		2002/0703		Formatting edit.
		2002/0820		Change Mach.intrts to uvlong.
		2002/0821		Add inidle and avginidle to Mach.
		2002/0822		Remove intrts, inidle, avginidle from Mach. Replace with Perf perf.
		2002/0824		Formatting, comment edit. Add FPillegal.
		2003/0301		Change ISAConf.irq to int.