From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ruedi.Hofer@ascom.ch Date: Tue, 01 Feb 2000 07:55:45 +0100 (CET) Subject: Re: Re: RomFS To: linuxppc-embedded@lists.linuxppc.org Message-id: <0FP80082UOL8BN@pmdf-it.hasler.ascom.ch> MIME-version: 1.0 Content-type: MULTIPART/MIXED; BOUNDARY="Boundary_(ID_Nj0OCXBFsDA7r1GmbVQDtQ)" Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: --Boundary_(ID_Nj0OCXBFsDA7r1GmbVQDtQ) Content-type: TEXT/PLAIN Content-Transfer-Encoding: 7BIT > Hi Hi! > That sounds good and it works. snip > > But how can I mount this rom/ramdisk from the kernel as its root disk? Well, um, you can't. I guess you have to write a simple read-only block device driver yourself... I think i've seen a posting before by a guy alex@signum.se who has written a flash file system, you might be able to steal some code from him. Search the linuxppc-dev and linuxppc-embedded lists. > What do I have to supply as boot parameter? > > I would like to store the entire application in the flash (kernel + application) If you have enough ram, make an initrd and load with 8xxrom (I don't remember the command, but i've done it.) But be sure to check/fix the ramdisk, it might be broken. I don't know your budget, but small ATA-Flash cards are cheap. And really nice. I've got a almost-working pcmcia driver waiting to be bugchecked and released here... And 8xxrom boots from ATA-Flash too. Cheers / Magnus > \Ruedi > > damm@kieraypc01.p.y.ki.era.ericsson.se on 31.01.2000 16:23:22 > An: Ruedi.Hofer@ascom.ch @ MailGate > Kopie: > Thema: Re: RomFS > > > Hi, > > Hi! > > > My ADS board is happily running with a NFS mounted linux box. > > Great! > > > Now I have to put all the code into the flash memory to get a standalone > > solution. > > > > I'm using the 8xxrom Bootloader. In a file called config.h I can configure > > CONFIG_DISK_ROM. As far as I can see, the bootloader assumes > > then that a complete FAT filesystem is stored from the position > > 0xFE020000 in flash. > > > > My question: > > - Is my assumption right? > > Well, there is a file in the disk directory called rom.c. > It is a simple read-only block driver for 8xxrom. > It does not know anything about filesystems, so you can use any filesystem you want > as long it is supported by 8xxrom. > > In rom.h can you find a define called ROM_DISKSTART which is the start address > of the filesystem. > > > - How can I produce a FAT filesystem in a file, which I can download > > with MPC8BUG into the onboard flash? > > You have to look somewhere on the net. > I usually create a ramdisk and make a filesystem and copy my things to it. > Then I umount it and use dd to copy the data to a file which I burn to > a flash. > > > - Does it have anything in common with the romfs driver which is supported > > by the kernel? (I think not) > > Nope. > But it would sure be great if we could read one romfs image from the 8xxrom. > > Good luck / > > magnus --Boundary_(ID_Nj0OCXBFsDA7r1GmbVQDtQ)-- ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/