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

[Masahiro Yamada]

Hi Michal,
Sorry for late reply. (I'm back from my vacations.)



> >>
> >> 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.
> 
> ok. Then I expect you are able to see at least u-boot SPL messages.

Yes. I can see them.


> 
> This is what I am getting - u-boot.img has full u-boot.
> 
> U-Boot SPL 2014.01-00816-ge0c1813-dirty (Jan 22 2014 - 17:56:37)
> mmc boot
> reading download.bit
>   design filename = "system.ncd;HW_TIMEOUT=FALSE;UserID=0xFFFFFFFF"
>   part number = "7z020clg484"
>   date = "2013/07/22"
>   time = "17:18:11"
>   bytes in bitstream = 4045564
> zynq_load: Align buffer at 100006c to 1000000(swap 1)
> reading system.dtb
> spl: error reading image system.dtb, err - -1
> reading u-boot.img
> reading u-boot.img
> 
> 
> U-Boot 2014.01 (Mar 19 2014 - 08:12:51)
> 
> Memory: ECC disabled
> DRAM:  1 GiB
> MMC:   zynq_sdhci: 0
> SF: Detected N25Q128A with page size 256 Bytes, erase size 64 KiB, total 16 MiB
> *** Warning - bad CRC, using default environment
> 
> In:    serial
> Out:   serial
> Err:   serial
> Net:   Gem.e000b000
> U-BOOT for zynq-zc702
> 
> Gem.e000b000 Waiting for PHY auto negotiation to complete.... done
> BOOTP broadcast 1
> BOOTP broadcast 2
> 
> Abort
> Hit any key to stop autoboot:  0
> U-Boot-PetaLinux>


Thanks!
Now I understand how to boot u-boot and Linux.


> > Full u-boot image of zynq enables CONFIG_OF_SEPARATE, right?
> > I think u-boot.img does not include device tree.
> 
> In mainline yes but I am not using it. It is nice for playing
> but it is fine just to disable it and you don't need to use dts at all.
> Just disable it in zynq config file.

I am not convinced why unsupported CONFIG_OF_SEPARATE is enabled.

U-boot mainline and u-boot-xlnx diverged with this point.
Which way are you going in your future development?
U-Boot control with device tree?  or without device tree?



> 
> >>>
> >>> 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.
> 
> ok. Then what are you trying to do? Just use latest u-boot?

Yes.
I want to run U-boot and Linux on a Zynq board.
I also want to use new features in the U-Boot mainline such as Kbuild.

That is my motivation to try to run u-boot-2014.04 on a zynq board.



> 
> >>> 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?
> 
> yes, I think it is not supported.
> I haven't had a time but Simon mentioned that they have
> enabled ITS format in SPL and it should be straight forward
> to do so. Then you can just use full ITS instead of DTB, kernel, ramdisk
> in separate images.

This sounds reasonable!
I am looking forward to it.


Best Regards
Masahiro Yamada