Using laest Uboot to boot a Pandaboard

Thanks to another recent fix to the OMAP4 rom it is now possible to use the lastest version of uboot to boot a Pandaboard ES. I’ve only tested it on a revision B1 Pandaboard ES. Hopefully it will also work on all Pandaboard revisions including the A3 Pandaboard.

You can download the latest version of uboot here.

You’ll need an OMAP4 rom built after 05/09/14 otherwise it will hang on boot.

The zip file also contains a utility to set the clock speed to 1500MHz on a Pandaboard ES. See the ReadMe file for details.
There’s also an updated !CPUTmpMon which shows both the current clock speed in GHz and temperature in degrees C on the Icon Bar.

You can also download the source code used to build this version of uboot here

If you want to build it yourself follow the below instructions.
I used Ubuntu 14.04 as the build environment but any recent Linux distribution should be ok.
A ARM cross compiler will need to be installed. This should be available in the Package repository.

git clone git://git.denx.de/u-boot-arm.git

Apply the following patch. This turns off the CPU caches. RISC OS hangs at HAL initialisation without it. Once it’s saved to a file use ‘git apply filename.patch’ to apply the patch.

diff --git a/include/configs/omap4_panda.h b/include/configs/omap4_panda.h
index 7378acd..cd1efc9 100644
--- a/include/configs/omap4_panda.h
+++ b/include/configs/omap4_panda.h
@@ -13,6 +13,13 @@
 #define __CONFIG_PANDA_H

 /*
+ * Turn off Caches. Stop RISC OS hanging at HAL initialisation
+ */
+
+#define CONFIG_SYS_ICACHE_OFF
+#define CONFIG_SYS_DCACHE_OFF
+
+/*
  * High Level Configuration Options
  */

make omap4_panda_defconfig
make CROSS_COMPILE=arm-none-eabi- clean
make CROSS_COMPILE=arm-none-eabi-

Using the Uboot and MLO files from the .zip file above, my Pandaboard ES won’t boot. I don’t get any video output.

(RISC OS 5.21 06-Sep-2014)

I put u-boot.bin instead of u-boot.img in the zip file. I’ve updated it with the correct file. If you download again and copy MLO and u-boot.img to the SD card it should work this time.

Does a warm reboot stable now?

Thanks Chris, that’s working great for me.
Slightly disappointing to see the CPU go from 10GHz to 1.20GHz though ;-)

Working here now too.
Nice work Chris!

I can’t get it to start !Boot. Only one of the green lights comes on, the right-hand one. !System disc says that it is a valid boot partition and !DiscKnight says “disc is Good”, but I think it is checking only the bootloader partition. I have used the files MLO, PREENV/TXT, U-BOOT/IMG and UENV/TXT from Chris Gransden’s website plus today’s ROM and Harddisc image. I notice that the file icon of U-BOOT/IMG has the word Atari on it, which seems a bit odd. My Pandaboard has the widget and so I didn’t include the file uenv_cmos/txt.

Try these instructions. Seems the uenv_cmos/txt (renamed as per the instructions) is important. HTH.

@Mike
Thanks for that. It has now booted up. I am puzzled about the need for the CMOS file as my Pandaboard has the widget and I didn’t have a CMOS file previously in the boot loader partition. I thought the widget held the CMOS settings.
Another question: Why does the icon for the U-BOOT/IMG file have Atari written on it?

Why does the icon for the U-BOOT/IMG file have Atari written on it?

There is no icon for the file…
The meta data for that file includes a filetype that the system is recognising as an Atari type file.
There is a system pool of sprites that give the visual aspect of files for any particular type.
If you change the filetype of the file to text (&FFF) it would show as a text “icon”

It has now booted up.

Glad you’ve got it sorted!

I am puzzled about the need for the CMOS file as my Pandaboard has the widget and I didn’t have a CMOS file previously in the boot loader partition. I thought the widget held the CMOS settings.

It’s all inscrutable magic to me but the way I read it, the system needs to know which device to boot from before it gets to the widget (no doubt others will tell me if I’ve got that completely wrong!).

See Ralph Barrett’s comment dated 7th Oct on this page.