From owner-freebsd-hackers Sun May 17 04:49:03 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id EAA12913 for freebsd-hackers-outgoing; Sun, 17 May 1998 04:49:03 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from elit.elit.chernigov.ua (elit.elit.chernigov.ua [193.125.84.11]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id EAA12812 for ; Sun, 17 May 1998 04:47:02 -0700 (PDT) (envelope-from al@cn.ua) Received: from cn.ua (al@dragon.cinet.cn.ua [193.125.84.115]) by elit.elit.chernigov.ua (8.8.8/8.8.8) with ESMTP id OAA08416; Sun, 17 May 1998 14:45:45 +0300 (EET DST) Message-ID: <355ECDE9.FBD954C6@cn.ua> Date: Sun, 17 May 1998 14:45:45 +0300 From: Alexey Lukin Organization: JSC CINET X-Mailer: Mozilla 4.05 [en] (X11; I; Linux 2.0.33 i586) MIME-Version: 1.0 To: ada@bsd.org, hackers@FreeBSD.ORG Subject: FreeBSD in embeded systems? References: <199805170828.SAA26744@noether.blah.org> Content-Type: text/plain; charset=koi8-r Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Hi! Ada wrote: > > ? I'm going to make FreeBSD booting from PCMCIA Flash card. Goal is > ? FreeBSD-based diskless router with > ? serial console and a lot of various network interfaces. I mean not only IP routers but control devices, networked controllers, etc. > > As has been said on -hackers, there are IDE-like fllash cards. > a friend of mine has built a bsd/os based router using one. > I have bcc'ed this to him to see if he wishes to contribute. Well, it's a good "first step" solution for router but it has 2 main drawbacks for embeded systems in general: 1) kernel gets biger with IDE drivers, and 2) booting time gets unacceptable for embeded systems. Imagine systen with watchdog timer: it should be ready after hardware reset in a very short time, but BIOS and kernel "thinks" appr 60-80 sec on IDE devices. Too long for my applications. Well, yet another little silly thing - fsck on real filesystem. It may wait for maintainer forever :-) So, tiny ISA board with watchdog timer, termometer and flashfile is more acceptable then IDE flash card or even simple flash memory like "Intel Flash 2" in standard PCMCIA controller. Bootblock flash like 28F008 can be used to put boot code in the right place, where BIOS cheks for ROM boot blocks. All I shold do to make FreeBSD work with such card is re-write boot code. I think that RAM disk should be used for root filesystem, and gziped images of it stored in flash memory. It allows to have different versions/configurations and easy boot-time config selection. This solution has drawback too: non-standard hardware, so I should develop all boot code and maintain it by myself. But I'm so lazy :-) Yet another problem with FreeBSD in embeded systems: gziped kernel and binaries are not supported as standard feature. Well, it's not a big deal, but flash chips are expensive yet. And what about real-time applicatios like control systems? AFIK, there's no such project for FreeBSD. Well, Linux has it all, but I like BSD :-) OK, guys, is all this stuff worth of discussion at least? :-) Any comments? Best regards, Alex. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message