[U-Boot] How to download image to U-Boot

[Grant Edwards <grant.b.edwards@gmail.com>]

On 2009-11-17, Wolfgang Denk <wd@denx.de> wrote:
> In message <hdurn4$2bt$1@ger.gmane.org> you wrote:

>> I've read through the U-Boot manual and FAQ, but I still
>> haven't figured out how one downloads via the network an image
>> to a board running U-Boot.  Previous projects have used
>> RedBoot, and it provided a couple different mechanisms: 
>
> There are many different ways in U-Boot - over serial line,
> over Ethernet using TFTP or NFS, from a number of different
> storage devices like MMC/SDCard, USB Mass Storage Devices,
> harddisks, ...
>
>> Both of these methods would work through firewalls and WAN
>> connections (even through satellite links), and could easily be
>> automated in an "updater" utility that is then provided to
>> customers to update images in flash.
>
> You don't have much of authentication in such an envrionment

True.

> which makes it unacceptable even for mimimum security
> envrionments.

False.

Almost all of our customers find it acceptible and it has never
proven to be a problem in the 10 years we've been shipping
product.  For the few customers who do use the products on an
usecured network, the update mechanisms can be secured.

> If you need such a szenario, then boot into a
> (minimal) Linux kernel, and run the update in a real OS.

So the answer is U-Boot doesn't support the sort of update
mechanism I'm talking about.  That's fine.  There's no reason
to get rude and insulting about it.

>> I can't seem to find out how one accomplishes the same task
>> using U-Boot.  The only method I can figure out involve setting
>> up a TFTP server (which is not going to be acceptible to
>> customers), and then typing a series of commands while plugging
>
> Why would this not be acceptable?

We can't require that the box is physically accessible or that
the customer have a serial port.

> Alternatively, you can use NFS (but I guess you will argument
> that setting up a NFS server is also not acceptable).

I'm afraid it isn't.

>> into a serial console (also not going to be acceptible to
>> customers).  The requirement is to update the image using just
>
> Ah, also not acceptable.

I'm sorry, what isn't acceptible?

> Of course you can kill any system by just excluding all
> available features as "not acceptable" - without giuving
> reasons for this, of course. Note that this works fine for
> many, many others, so you might want to ask yourself if your
> requirements are "acceptable".

My opinions have nothing to do with it, and they're not my
requirements.  I'm perfectly happy setting up a TFTP server and
using a serial console.  Our customers, however, are neither
willing or able to up special servers in order to update the
firmware in our products.

>> I found mention of netconsole, but I don't see how it's useful
>> since you have to know a-priori the address of the machine
>> from which you want to use it.  It would seem that you have to
>> force
>
> You don't have to.  You can use broadcasts.

That's not going to work through firewalls.

>> the customer to change the IP address of their machine (not
>> acceptible).
>
> Why am I not surprised that this is not acceptable, either?

Because it's not something our customers are willing to do.

I take it that your position is that everying that U-Boot
doesn't support is worthless and stupid as are people who
desire or currently use such features.

Thanks.

-- 
Grant Edwards                   grante             Yow! Am I SHOPLIFTING?
                                  at               
                               visi.com