From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from majordomo by infradead.org with local (Exim 3.20 #2) id 14VaGZ-0004oA-00 for mtd-list@infradead.org; Wed, 21 Feb 2001 14:29:15 +0000 Received: from smtp.alcove.fr ([212.155.209.139]) by infradead.org with esmtp (Exim 3.20 #2) id 14VaGN-0004o3-00 for mtd@infradead.org; Wed, 21 Feb 2001 14:29:14 +0000 Received: from champlain.alcove-int ([10.16.110.20]) by smtp.alcove.fr with esmtp (Exim 3.12 #1 (Debian)) id 14VaG6-0001qN-00 for ; Wed, 21 Feb 2001 15:28:46 +0100 Received: from raceme by champlain.alcove-int with local (Exim 3.12 #1 (Debian)) id 14VaFx-00039Y-00 for ; Wed, 21 Feb 2001 15:28:37 +0100 Date: Wed, 21 Feb 2001 15:28:36 +0100 From: Christophe Boyanique To: mtd@infradead.org Subject: M-sys or MTD for production use ? Message-ID: <20010221152836.A12119@fr.alcove.com> Reply-To: Christophe.Boyanique@fr.alcove.com Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit Sender: owner-mtd@infradead.org List-ID: Hi folks, I'm relatively new with embedded system and DiskOnChip so I'll try to avoid asking dumb questions. I'm working on a embedded project using an almost standard pc arch, one DiskOnChip and rtlinux. The driver used are old ones from M-sys (version 2.2) and we are using plilo (0.20) supplied with the drivers and a 2.2.17 rtlinux kernel. The first problem we encountered was the inability to send command line parameters to the kernel (neither by lilo.conf nor lilo commande line). After some hacking thru the kernel and lilo sources we found that lilo use 0x90000 memory address to store parameters, and later during the init, the kernel read the parameters from this area. But at this moment all the data are scrambled and obviously command line arguments are gone. I tried to port the lilo-patch 0.20 to version 0.21 of lilo by hand (the patch is pretty small) and tried my new plilo. With that, I just get the L of LILO and an infinite loop displaying AA. Just for testing, I tried to compile myself plilo 0.20 (from the official lilo 0.20 sources and the patch supplied by M-sys) and I found that it doesn't produce the same binary ! I get to LIL with this one, but no more kernel booting. After that I began to search some fresh meat about the DiskOnChip ;) and found the new M-sys drivers (4.2.1) and the MTD project. >>From now I have to choose one solution that will be used in production and I'd like people to correct my following reflexions if I made some mistakes: M-sys: ------ - new drivers seem to be GPL compliant if used as module event if the closed linked .obj file is not really nice. -> use of a ramdisk is required. - new version needs the updated firmware to work. - the new pLilo 0.21 supplied seems to make some manipulation from preventing command line corruption (it uses a temporary buffer at 0x80000 and paste it at 0x90000 later). BUT I didn't find any statement to be sure that the pLilo/firmaware combination is now entirely safe. - For booting from the DOC, only pLilo is usable. MTD: ---- - I didn't find any statement about the stability of MTD and the use in a production environment. - MTD supply an hardware-specific kernel driver (the DOC firmware is no more needed). - For booting from the DOC, mtd-lilo or mtd-GRUB (developping stage and reliability ?) are usable. Common points: -------------- - the driver patch supplied apply to 2.2 and 2.4 kernel. I have also silly questions: ---------------------------- - What are the differences between pLilo 0.21 and mtd-lilo ? and some requirements: ---------------------- - we have another model using a Compaq flash card seen as an IDE drive by the system (so nothing special here) and we want to use the same distribution (same boot loader: for example we want to type lilo, and it will find itself that this is a DOC or a regular IDE drive, and choose the right loader by himself). - we need to use the kernel command line (by typing on the bootloader command line or by lilo.conf (grub.conf?)). - we need the serial console support in the bootloader. Thanks for having reading all that and I'm looking forward reading you ;) Christophe. -- Christophe Boyanique - Free Software Engineer -------- Alcove : Liberating Software -------- http://www.alcove.com - Tél: +33 149 226 795 To unsubscribe, send "unsubscribe mtd" to majordomo@infradead.org