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Re: TS7200_INSTALL kernel problem solved - kernel too big!

In message: <494192D2.3050505%embeddedARM.com@localhost>
            Jesse Off <joff%embeddedARM.com@localhost> writes:
: Ken Hornstein wrote:
: >> u-boot has those features now, but not redboot.
: >>     
: >
: > Yeah, I think that unless Embedded ARM wants to switch to u-boot, that 
: > help us.  Ah, well.
: >
: > --Ken
: >
: >   
: We're not a big fan of either u-Boot or RedBoot out here.  Seems like 
: overkill to write one OS to for the sole purpose of starting up 
: another.  I personally prefer to minimize how many drivers I write or 
: debug for the same hardware.  :-)


: In our new products, we have written a 442 byte bootloader that loads 
: kernels from x86 MBR style partitions of either NAND flash or SD card 
: and can boot a small Linux kernel + ramdisk in about the same amount of 
: time it takes the RedBoot or u-boot bloatware to start up.  Once up, we 
: have written a Linux program + kernel module that can start up other 
: OS's, RTOS's, and OS-less applications.  In effect, we use Linux as our 
: bootloader so that you could load kernels via NFS over USB wifi dongle 
: and configure pre-bootup behavior in shell script, etc...

442!  Wow!  I was all proud of a 9k boot loader I wrote for the
AT91RM9200 that I was working that loaded kernels off a ufs partition,
including a SD/MMC card isolation and reading stack and keyboard
interrupt/kernel name entry...  I stopped at 9k since that easily fit
in the 12k+4k stack that you have in the initial program load on that
SoC.  I was bummed to see that newer at91 parts had only 4k of RAM for
the initial load, which was going to be a big stretch....  but I

: Here's some info on it: 
: http://www.embeddedarm.com/software/arm-linux-bootloader.php
: I ported the bootload utility to NetBSD too-- it doesn't even need a 
: kernel module. I do what I need to do there via /dev/mem and /dev/kmem.
: This application + kernel module should also work on the default TS-7200 
: Linux installation.  You can place the NetBSD kernel on the Linux JFFS2 
: filesystem and then run our "bootload" command to soft-boot into another 
: OS.  On the platforms we've standardized on this scheme we can go from 
: power-on to Linux to another OS in about 3 seconds or so.  The TS-7200 
: Linux boots up a little slower, but its still not too bad.

Well, at least I got this same speed: power on to mounting a FreeBSD
root was between 2s and 3s...

Very cool that you can do similar in so much less...


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