[U-Boot] [Question] Linux Boot with u-boot 2014.04 on Zynq board

[Masahiro Yamada]

Hi Michal.

Thanks for your reply.

> 
> Before you build u-boot you have to copy ps7_init.c/h from your
> hw design to the u-boot if you want to use SPL.

Oops, I forgot to mention this.
I did that.



> > [1] Build u-boot
> > [2] Convert  spl/u-boot-spl.bin into  boot.bin
> >       with BootGen tool
> 
> yes - or if you look at xilinx git u-boot repo we have one
> simple python script which does this automatically without bootgen.

I found tools/zynq-boot-bin.py
Is this the one you mentioned?


> > [3] Copy "boot.bin" to FAT-fomatted SD card.
> 
> yes.
> 
> I personally use SD boot mode it means boot.bin has just u-boot SPL
> and u-boot.img on SD stores full u-boot.

On u-boot 2014.04 release, I don't know how to use full u-boot either.

Full u-boot image of zynq enables CONFIG_OF_SEPARATE, right?
I think u-boot.img does not include device tree.

Should I combine u-boot.img and device tree by myself? Like this?

cat u-boot.img u-boot.dtb > u-boot.img.tmp
mv u-boot.img.tmp u-boot.img

Or should I disable CONFIG_OF_SEPARATE?




> Keep in your mind that using U-BOOT SPL is not fully supported flow.
> Supported flow is fsbl->u-boot->linux.

OK.
Maybe I should stick to the old flow.

> > 
> > My question is, how to pass an init ramdisk?
> 
> I am using cpio compiled in directly in the kernel.
> 
> > In which file-name  should I copy init ramdisk
> > into SD card?
> 
> Xilinx OSL versions are using initramdisk
> which you can download here.
> http://www.wiki.xilinx.com/Zynq+2014.1+Release

Yes. I am using this.


> > How should I load the init ramdisk  from the  SD card?
> 
> And this is the command which OSL version are using.
> 
> 	"sdboot=if mmcinfo; then " \
> "run uenvboot; " \
> "echo Copying Linux from SD to RAM... && " \
> "fatload mmc 0 0x3000000 ${kernel_image} && " \
> "fatload mmc 0 0x2A00000 ${devicetree_image} && " \
> "fatload mmc 0 0x2000000 ${ramdisk_image} && " \
> "bootm 0x3000000 0x2000000 0x2A00000; " \
> "fi\0" \
> 

Yes. I know this works.
But in my understanding, SPL cannot use this command.

My question is how SPL can load the init ramdisk.

It looks like spl_load_image_fat_os() function loads
"system.dtb" and "uImage".
But I could not find which code loads ramdisk.
Not supported yet?

Best Regards
Masahiro Yamada