From mboxrd@z Thu Jan 1 00:00:00 1970 Message-Id: <200007240717.JAA26318@denx.local.net> To: mark@sps.la.asu.edu cc: linuxppc-embedded@lists.linuxppc.org Subject: Re: Porting linux ppc to new platform From: Wolfgang Denk Mime-version: 1.0 Content-type: text/plain; charset=ISO-8859-1 In-reply-to: Your message of "Sun, 23 Jul 2000 20:12:13 PDT." Date: Mon, 24 Jul 2000 09:17:39 +0200 Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: Dear Mark, in message you wrote: > > Recently I have begun working with ppc and have ported vxWorks to our > platform and am now interested in porting linux. I have gotten the RPX > lite board to boot, but then I really did not have to do anywork. Check the Embedded PowerPC HOWTO at http://members.xoom.com/greyhams/linux/PowerPC-Embedded-HOWTO.html > What I'm intrested in is others who have ported linux to embedded platforms > so that I might ask them the amount of work invovled and where is a good > place to begin. This will be on a board with no available firmware or drivers, > although I can perform enough low level configuration to bring up vxWorks. There are several Open Source firmware projects: * PPCBOOT - Embedded PowerPC Linux Boot Project - MPC8xx, MPC82xx Homepage: http://ppcboot.sourceforge.net/ Download: ftp://ftp.denx.de/pub/ppcboot or CVS on Sourceforge * LiMon - Linux Monitor - SBC8260 Homepage: http://www.thinsys.com/limon.html Download: http://www.thinsys.com/limon-1.4.2.tar.gz * PBOOT - PMON/2000 BootROM Monitor - 603e, 604, 604r, 740, 750 Homepage: http://pmon.groupbsd.org/ Download: ftp://pmon.groupbsd.org/pub/PMON/src/ > Is there specific memory layout required, what types of cpnfiguration is Yes. Life will be easier for you when RAM starts at 0 and IMMR is at 0xFFF00000 (assuming you stay on MPC8xx as the use of an RPX lite indicates). > neccessary at the hardware layer (immr, sypcr, icdct, mamr level stuff, etc.). These things are usually done by the firmware. > What do I need to do vs. what is done in the ppc kernel after it is capable > enough to load a C program. Is there a powerpc equivalent to lilo, > or is this even needed. Can I just jump to main.c? Using PPCBOOT, you can "jump" to the entry point "_start" in arch/ppc/kernel/head.S using the "bootm" command - but this includes _some_ initialization (like loading and uncompressing the kernel image) and parameter passing. With more traditional firmware, you will have to modify the code in the arch/ppc/mbxboot diretory to fit to the interfaces provided by your firmware. > I have many more questions, but if these aqre answered by a FAQ I'll hold off until I can investigate more. I guess the HOWTO mentioned above will answer some, but not all. Wolfgang -- Software Engineering: Embedded and Realtime Systems, Embedded Linux Phone: (+49)-8142-4596-87 Fax: (+49)-8142-4596-88 Email: wd@denx.de There's no sense in being precise when you don't even know what you're talking about. -- John von Neumann ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/