[U-Boot] U-Boot for the Socfpga Arria10 board

[Simon Goldschmidt]

Am 18.11.2019 um 19:08 schrieb Wolfgang Grandegger:
> Hello,
> 
> I'm trying to understand what is necessary to get mainline U-Boot
> booting from the eMMC of an Arria10 board, which is significantly
> different to the Cyclone 5.

Unfortunately, my playground here is limited to Cyclone 5, but from the 
U-Boot side and from what I know, booting an Arria 10 should be very 
similar to Cyclone5 (given that Stratix 10 and Agilex have a very much 
different boot flow).

Do you have vendor U-Boot running? If not, I suggest to first get that 
running. The step to mainline U-Boot should then hopefully not be too hard.

> 
> I'm playing with U-Boot v2019.10! I find some related documentation at
> [1]. Section "Arria 10 SoC - Boot from SD Card " seems to apply to the
> mainline U-Boot as well, at a first glance. Is there some similar doc
> for mainline U-Boot? What are the differences in mainline? Is it working
> or is something missing?
> 
> So I need at least three partitions on the eMMC:
> 
> 1. VFAT partition with u-boot.img and fit_spl_fpga.itb
> 2. A2 partition with 4x u-boot-spl.sfp (or u-boot-with-spl.sfp)
> 3. Linux partition
> 
> Where do I specify the physical number of the partition 1.?

In the config (or via menuconfig), set 
CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_USE_PARTITION to y and 
CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION contains the partition number

> 
> Is it still possible to load the secondary bootloader (u-boot.img) from
> offset 0x800 of the A2 partition? It seems that "SPL_FS_FAT" breaks it.

Yes, and no. Enable the above and enable 
CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR as well then 
CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR controls the offset in this 
partition. However, this uses 
CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION, which is not necessarily the 
same as the boot-ROM-detected A2 partition.

Hope that helps.

Regards,
Simon