[U-Boot] arm: mvebu: ClearFog: booting u-boot from ssd?

[Stefan Roese]

Hi Florian,

On 16.02.2018 11:23, Florian Klink wrote:
> Hey,
> 
> I tried getting ClearFog to load u-boot from a M.2 SSD (via SATA)
> 
> So I built u-boot-spl.kwb
> 
>> make clearfog_defconfig
>> make -j4 ARCH=arm CROSS_COMPILE=arm-none-eabi-
> 
> dd'ed it on the SSD:
>>  dd if=u-boot-spl.kwb of=/dev/sdX bs=512 seek=1
> 
> changed SW1 dip to 11100, and got this:
> 
>> BootROM - 1.73
>> Booting from AHCI
>> Probing HBA- 0 port 0  SATA device found
>> BootROM: Bad header at offset 00000001
>> BootROM: Bad header at offset 00000022
>> BootROM: Bad header at offset 00001000
>> BootROM: Bad header at offset 00002000
>> BootROM: Bad header at offset 00003000
>> BootROM: Bad header at offset 00004000
>> BootROM: Bad header at offset 00005000
>> BootROM: Bad header at offset 00006000
>> BootROM: Bad header at offset 00007000
>>
>> Trying Uart
> 
> According to the clearfog wiki and uboot-armada38x src tree, there are 
> separate
> images for sd and sata, with the makefile there calling
>> $(obj)tools/marvell/doimage -T mmc -D 0x0 -E 0x0 -G 
>> $(obj)tools/marvell/bin_hdr/bin_hdr.bin u-boot.bin u-boot.mmc
> vs
>> $(obj)tools/marvell/doimage -T sata -D 0x0 -E 0x0 -G 
>> $(obj)tools/marvell/bin_hdr/bin_hdr.bin u-boot.bin u-boot.sata

Please note that this "should" not be needed when using mainline
U-Boot on A38x. All necessary tools for image generation are
included here.

> According to uboot-armada38x's tools/marvell/doimage_mv/doimage.c, this 
> seems to
> result in different
> 
>   hdr->blockID = IBR_HDR_SATA_ID; //0x78
>   hdr->blockID = IBR_HDR_MMC_ID; //0xAE
> 
> and maybe another hdr->sourceAddr baked into the image header [1]
> 
> Mainline u-boot also knows about IBR_HDR_SATA_ID (tools/kwbimage.h),
> and has a mapping in tools/kwbimage.c (boot_modes[]), which seems to decide
> depending on the 'BOOT_FROM' setting in 
> board/solidrun/clearfog/kwbimage.cfg
> This is currently hardcoded to 'sdio' (which will be translated to 0xAE ==
> IBR_HDR_MMC_ID).
> 
> Am I missing something completely obvious, or does this mean there need 
> to be
> different image headers depending on boot medium type BootROM tries to load
> u-boot from (so it might be desirable to make this configurable)?

You are correct. The image header differs depending on the boot media.
You need to change the BOOT_FROM line in the .cfg file accordingly, if
you want to boot from SATA.

> Are there already any efforts being taken on that? Most likely we'd also 
> need to
> enable SATA drivers, so u-boot is able to read the kernel, which might 
> be on
> that disk.

Correct. If the SATA driver is not enabled yet, then this has to be
done for this board. A38x has an AHCI compatible SATA controller, so 
this is the controller / driver to use. I suggest to look at the Marvell
dev-board "db-88f6820-gp" for this.

Thanks,
Stefan