[U-Boot-Users] USB Host support

[Wolfgang Denk]

In message <11273166.post at talk.nabble.com> you wrote:
> 
> Let me elaborate a bit: We're thinking of having a kind of a "Disk on key"
> device as our primary non volatile storage. The Linux software image will be
> on this device, so we'll need to boot from it as well. As this is an MPC85xx
> based board, having no embedded USB controller, we'll also need an external
> PCI to USB 2.0 host controller. Writing may be needed as in our current boot
> process the boot application writes some temporary files on the HD (and it's
> also needed at development stage, when there is no image on the disk).

It is not needed. Boot Linux over Ethernet, and use the running Linux
system to write the files.

> I basically would like to know how painful it is to have all this ticking
> with the current u-boot support.

It *is* painful, as you would have to add write support both  to  the
USB  drivers  (including re-testing on a lot of boards) *plus* to the
file system drivers (including re-testing on a lot of boards).

It's simply not worth the effort. U-Boot is a boot loader, and if you
need the services of a typical OS (like  full  file  system  support)
then  you  should  just boot an OS - that's what U-Bootis really good
in.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Sometimes a feeling is all we humans have to go on.
	-- Kirk, "A Taste of Armageddon", stardate 3193.9