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From: Warner Losh <imp@bsdimp.com>
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Cc: gnn@freebsd.org, freebsd-small@freebsd.org
Subject: Re: Flash File Systems or Translation Layers?
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> The driver for 'this' ;-) is that most bootloaders can't read the  
> (root) filesystem.  By putting the
> kernel out in the flash somewhere, its easy for the loader to read  
> the kernel into memory, do a bit
> of setup, then 'jump' to the kernel.  The kernel can load the root  
> filesystem (or the boot loader can read it
> into memory somewhere, if necessary.)

I'm working on porting the i386 boot2 to the arm part that I'm working
on.  I've written a loader from almost scratch for it (started with
the bootloader that came with an eval board).  I'll add support for
booting off of SD cards and SPI flash memory parts that have been
partitioned using UFS.  I'm not sure how much sense it makes to use
UFS for the SPI part that will just have a kernel, a FPGA image and a
RAM disk on it, but it makes good sense for a SD card that will look
like a more traditional system.

Warner