autoboot of UP Linux image on DE1-SoC fails

Re: autoboot of UP Linux image on DE1-SoC fails

The problem is not due to writing the SD card with dd, that's OK. It rather seems to be a preloader problem, in this version of the UP Linux image. I found the previous Image build as of October 18, 2016, at https://xdevs.com/doc/ALTERA/Terasic_DE1SoC/DE1-SoC-UP-Linux.zip that boots successfully. A comparison of the U-Boot startup sequence output in the PuTTY terminal in this case, with that reported for the newer Image, may suggest something about the possible preloader problem with the latter:

U-Boot 2013.01.01 (Apr 25 2014 - 04:59:35)

CPU : Altera SOCFPGA Platform

BOARD : Altera SOCFPGA Cyclone V Board

I2C: ready

DRAM: 1 GiB

MMC: ALTERA DWMMC: 0

In: serial

Out: serial

Err: serial

Net: mii0

Hit any key to stop autoboot: 0

reading uImage

4315040 bytes read in 385 ms (10.7 MiB/s)

reading socfpga.dtb

19147 bytes read in 7 ms (2.6 MiB/s)

reading soc_system.rbf

2316870 bytes read in 209 ms (10.6 MiB/s)

## starting application at 0x3FF7D4F8 ...

## Application terminated, rc = 0x0

## Booting kernel from Legacy Image at 00007fc0 ...

[...]

The kernel startup runs fine, but the following output is perhaps relevant to the subject problem, since it relates to mounting the SD card:

[ 2.270471] EXT3-fs (mmcblk0p2): error: couldn't mount because of unsupported optional features (240)

[ 2.281243] EXT2-fs (mmcblk0p2): error: couldn't mount because of unsupported optional features (240)

[ 2.308475] EXT4-fs (mmcblk0p2): mounted filesystem with ordered data mode. opts: (null)

I wonder whether the preloader in the newest version fails because of inability to recognize the filesystem type (ext4) mounted in the Linux partition.