How many people have actually done this on an EST board? I don't doubt that the chip can do it, but I have my doubts about the EST PLL (clock) filter circuits being correct to begin with, let alone conforming to the errata.
On Mon, 11 Dec 2000, Gessner, Matt wrote: > I had no problem at all getting this to work at 66MHz. > DO NOT RUN THE CPM FASTER THAN 133MHZ (at least on the chips I had, > it NEVER worked). > Yes. I'd gladly settle for 200/133/66. > In fact, I clocked my 166/133/66 chip at 300MHz :-) > That baby RUNS! Heh. > > > -----Original Message----- > > From: Brian Ford [mailto:ford at vss.fsi.com] > > Sent: Friday, December 08, 2000 1:47 PM > > > > Is there any magic in getting the EST8260 board to work with > > a 66 Mhz bus clock? I haven't had good luck with a Linux or vxWorks > > image. > > > > My board has a 200/166/66 rev A.1 chip. > > > > I boot using a vxWorks bootrom. I have made a few corrections to the > > bootrom so the decrementer frequency is set correctly from the user > > dip switches in addition to setting the core, cpm, and bus speeds. > > > > The scenerio is as follows: > > > > 1.) Burn configuration word to change MODCK_H from 0x0001 to 0x0101 > > 2.) Swap oscillators 33.0 -> 66.0 Mhz > > 3.) Set MODCK[1-3] switches to 0x111 (200/133/66) > > 4.) Mirror 3.) on user switches for vxWorks bootrom to read > > 5.) Hack head_8260.S to put immr in place for Linux > > 6.) Set linux board info in embed_config.c to 200/133/66/66 > > (core,cpm,bus,brg) making sure there is real space allocated for it > > instead or whatever was in r3 when vxWorks booted us. > > 6.) Reboot. > > > > vxWorks bootrom runs fine and downloads Linux or vxWorks. > > > > Linux pannics just before giving me a shell prompt somewhere > > in tty init. > > > > vxWorks appears to come up fine, but the muxDevBind fails for the Fast > > Ethernet and thus no network communications. Even though the bootrom > > just downloaded us successfully over the same interface. > > > > Has anyone had any luck with the 66 Mhz bus clock? > > -- Brian Ford Software Engineer Vital Visual Simulation Systems FlightSafety International Phone: 314-551-8460 Fax: 314-551-8444 ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
