From: Matthias Fuchs <matthias.fuchs@esd.eu>
To: u-boot@lists.denx.de
Subject: [U-Boot] mx28: booting u-boot via USB
Date: Tue, 31 Jan 2012 16:19:46 +0100 [thread overview]
Message-ID: <4F280692.2000602@esd.eu> (raw)
In-Reply-To: <20120131142503.GI2056@build.ihdev.net>
On 31.01.2012 15:25, Sergey Lapin wrote:
> On Tue, Jan 31, 2012 at 03:03:55PM +0100, Matthias Fuchs wrote:
>> Hi,
>>
>> I have a problem booting the current u-boot-imx version
>> on a MX28EVK via USB. The i.MX28 CPU supports a special boot mode
>> where the image (sb boot stream) is downloaded via USB device
>> (all DIP switches in position 'off' on the EVK). The
>> CPU's internal bootrom implements a HID device in this mode.
>> Freescale provides a download tool "sb_loader" for this purpose.
>> There is also a GPL'd implementation based on libusb.
> Could you please provide link to GPL tool?
check http://svn.rockbox.org/viewvc.cgi/trunk/utils/imxtools/
The code builds fine against a recent version of libusb. I tested it
against the mx28evk.
>>
>> So back to my problem:
>>
>> I build u-boot from the u-boot-imx repository. This runs fine
>> when booting from SD/MMC or SPI-flash. But the console stays dark
>> when using the USB download mode. USB download works fine with the
>> Freescale provided U-Boot sources together with the imx-bootlets
>> SPL code.
>>
>> Now I digged a little bit deeper to find out the cause:
>>
>> When downloading via USB I saw the SPL running correctly.
>> board_init_ll() (arch/arm/cpu/arm926ejs/mx28/start.S) runs through
>> correctly. Then control is passed back to the bootrom. That's
>> where things end as far as I can see.
>>
>> The 2nd stage of u-boot is not started.
>>
>> The USB boot mechanism is not documented that detailed.
>> Is it possible that the SPL code overwrites the bootroms ivt and
>> in consequence crashes the bootrom's USB code? Any further ideas?
> I'd look at difference in linking scripts and addresses in
> freescale u-boot and new u-boot.
> This might be some memory addressing issues. Had some of this with
> i.MX23. Also, some hardware might be not powered on or is powered
> off by SPL.
That's a good catch. I will check Fabio's idea in just a minute.
Matthias
next prev parent reply other threads:[~2012-01-31 15:19 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-31 14:03 [U-Boot] mx28: booting u-boot via USB Matthias Fuchs
2012-01-31 14:25 ` Sergey Lapin
2012-01-31 15:19 ` Matthias Fuchs [this message]
2012-01-31 14:53 ` Fabio Estevam
2012-01-31 15:34 ` Matthias Fuchs
2012-02-03 11:23 ` Matthias Fuchs
2012-02-03 12:52 ` Matthias Fuchs
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4F280692.2000602@esd.eu \
--to=matthias.fuchs@esd.eu \
--cc=u-boot@lists.denx.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.