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diff --git a/sys/contrib/dev/fla/README b/sys/contrib/dev/fla/README new file mode 100644 index 0000000..78433de --- /dev/null +++ b/sys/contrib/dev/fla/README @@ -0,0 +1,198 @@ + README and FAQ for the fla driver. + ================================== + + +[0] COPYRIGHT & LICENSE + + Please read the COPYRIGHT file carefully. If you cannot + agree to be bound by the terms of this license, please + contact M-systems and make arrangements with them. + +[1] What does this driver do ? + + This driver supports up to eight M-systems DiskOnChip + devices. + + The driver has been tested with the following devices: + + DiskOnChip2000 (8, 12, 24, 32, 40, 72, 144 MB) + DiskOnChipMillenium (8 MB) + DiskOnChipMillenium TSOP (8 MB) + + You can find full details, specs etc on M-systems homepage: + http://www.m-sys.com + +[2] Which firmware version ? + + The driver has only been tested with version 1.21. + +[3] How many devices ? + + The driver supports up to 8 devices but have been tested only + with 5 due to hardware limitations in my test setup. + +[4] Which FreeBSD versions ? + + The driver is tested for 4.0-CURRENT and 3.3-RELEASE. + + Porting to earlier versions of FreeBSD should be a simple + matter of modifying the fla.c file. [patches are welcome] + +[5] Can I install FreeBSD with sysinstall ? + + Yes, it has been tested in FreeBSD-4.0-CURRENT and it works. + You will need to build a kernel with the fla driver since + the default "GENERIC" kernel doesn't contain the fla driver. + +[6] How to boot from a fla device ? + + FreeBSD 4.0 and forward find their root device by reading + the /etc/fstab, so the DiskOnChip devices will work just + like any other device. + + Earlier FreeBSD kernels recognizes the root device using + various hacks. These hacks doesn't recognize the fla device + so some "real" hacks are needed to boot from your fla + device. + + In pre 4.0 versions specifying the boot device in the kernel + config file this way is the easiest way to do it: + + config kernel root on major 28 minor 65538 + +[7] How to disklabel a fla device ? + + Look at the script in prep.fla.sh, it will do the job for you. + +[8] Who to contact ? + + doc2k@phk.freebsd.dk will offer limited best-effort help + to the extent time permits. Further support for special + projects or configurations available at reasonable hourly + rates. + +[9] Getting detailed + + The DiskOnChip product gets out in some odd corners of the + PC-architecture, and chances are that things don't do what + you expect. Here are some hints and random observations + I've made during my work with these devices. + +[9a] Choosing an address for the DOC + + Each DOC needs a 8K memory window starting on an 8K boundary. + The lowest possible address is C000:0, the highest is DE00:0 + + If your hardware puts the DOC another place, you will need + to modify the doc2k_probe() call in fla.c. + + It is important that you set the BIOS to not do "fancy things" + with this window, in particular no kind of cache or shadowing + can be enabled. + + Be aware that some hardware will decode a 32k memory window + for the DOC device. + + If everything is OK, the DOC will print a message during + the BIOS startup. + + For large devices it can take some time to check the flash + data structures, but if it takes more than 3 minutes + something is wrong. + + If you boot a MSDOS floppy and run FDISK you should be able + to see the DOC device. + + If it doesnt work: + + If you machine never gets to the point where it will boot, + but just hangs it could be because you have a BIOS which + need the "slightly special" DOC firmware. Obviously you + will need to put the DOC in another machine to load this + firmware. You can download the firmware and utilities + from M-systems website http://www.m-sys.com + + If the machine boots, but the device isn't visible it can + be because some other device uses the same memory window, + or because the BIOS prevents it from being used. If you + boot MSDOS and enter DEBUG, you should be able to find a + BIOS extension signature at the address using the 'd' + command, for instance 'd d800:0'. + + A special case is when the DOC prints the BIOS message + but disappears afterwards, this can happen because another + card (NCR SCSI controllers for instance) steal the memory + window later in the boot process. In such a case the + above check with DEBUG will not show the BIOS signature. + +[9b] So just who is drive 'C' here anyway ? + + Using the DUPDATE program you can choose to have the DOC + add itself at the front or the back of the device list. + + This is, unfortunately not the only thing affecting the + drive order, the above mentioned NCR SCSI controllers also + have some builtin AI, and the result can be very confusing + because the DOC will come before even the floppy as a result. + + There is no simple solution for this case, only variuos + work-arounds. But chances are good that most users will + not use both a DOC and a SCSI in the same system, except + maybe for initial programming. + +[9c] MBR/fdisk + + The boot firmware in the DOC and/or the FreeBSD bootblocks + mandate that the first MBR slice/(partition in FDISK lingo) + start exactly at "sector #1, head #1, cylinder #0." You + will have problems booting from the fla if you don't get this + right. The prep.fla.sh script will do this for you. + + DO NOT WRITE JUNK IN THE MBR! The DOC firmware relies on + various fields and can get utterly confused if they don't + make sense. + +[9d] Getting the FreeBSD kernel to use the fla as root + + Please see above under item 6. + +[9e] I turned the machine off while it was running and now my + DOC hangs during boot/panics the machine/does weird things. + + If a write operation to the DOC gets interrupted by reset + or power-failure, it can happen that the flash data structures + are left in a state the sofware cannot cope with. + + Your best chance is to DUPDATE, DFORMAT the device again. + + If it hangs during boot, you can use this particular dirty + trick ENTIRELY AT YOUR OWN RISK! DO NOT COMPLAIN IF THIS + DOESN'T WORK FOR YOU OR IF YOU DESTROY YOUR COMPUTER OR + DOC DEVICE DOING IT! + + Jumper the DOC for an address which will not work, but which + will not interfere with the system either, C000:0 seems to + work pretty universally for this. + + Boot MSDOS and rejumper the DOC for its real (working) address. + + Run DUPDATE and use the /win:xxxx argument to point it at the + DOC device. + +[9f] Apart from that... + + ...the DOC is just like any other disk, but it is silent, + has better MTBF and doesn't take up a lot of space. + + +[10] History + + The fla driver was written by Poul-Henning Kamp <phk@FreeBSD.org> + under contract for M-systems, and using their "OSAK" + development kit. + +Good Luck, + +Poul-Henning + +$FreeBSD$ |
