Variscite DART-6UL - upgrade zeus to scarthgap

tloten
Sun, 09 Feb 2025 21:59:45 +0000
General Discussions

I’m attempting to update a Zeus build to Yocto Scarthgap. The Zeus build was created by following the instructions in the first post in this thread.
A few things required tweaks to support Scarthgap - the u-boot patches needed re-applying, and manually tweaking the conf files.
Now it’s building fine, however the boot process is having trouble.
This is the 2nd attempt I’ve had at this - the first was targeting Kirkstone, however it ran into this exact same boot issue:

Here is the boot log:

U-Boot SPL 2018.03+g9d5b55aeed8+p0 (Oct 18 2024 - 19:06:56 +0000)

Part number: VSM-VS6UL-101
Assembly: AS2104164477
Date of production: 2021 May 04
SOM configuration: eMMC WiFi
Trying to boot from MMC1
MMC Boot Device: mmc0 (SD)


U-Boot 2018.03+g9d5b55aeed8+p0 (Oct 18 2024 - 19:06:56 +0000)

CPU:   Freescale i.MX6ULL rev1.1 900 MHz (running at 396 MHz)
CPU:   Commercial temperature grade (0C to 95C) at 37C
Reset cause: POR
Board: Variscite VAR-SOM-6UL
I2C:   ready
DRAM:  512 MiB
MMC:   FSL_SDHC: 0, FSL_SDHC: 1
Loading Environment from MMC... OK
Display: VAR-WVGA-LCD (800x480)
Video: 800x480x24
** Unrecognized filesystem type **
Error: could not access storage.
In:    serial
Out:   serial
Err:   serial
eMMC:  7.3 GiB
Codec: wm8731
Net:   got MAC0 address from fuse: f8:dc:7a:5b:a4:1e
FEC0 [PRIME], usb_ether
Error: usb_ether address not set.

Normal Boot
Hit any key to stop autoboot:  0
switch to partitions #0, OK
mmc0 is current device
Scanning mmc 0:1...
32167 bytes read in 20 ms (1.5 MiB/s)
Found EFI removable media binary efi/boot/bootarm.efi
Scanning disks on usb...
Disk usb0 not ready
Disk usb1 not ready
Disk usb2 not ready
Disk usb3 not ready
Scanning disks on mmc...
MMC Device 2 not found
MMC Device 3 not found
Found 10 disks
466944 bytes read in 39 ms (11.4 MiB/s)
## Starting EFI application at 82000000 ...


EFI stub: Booting Linux Kernel...
EFI stub: Entering in SVC mode with MMU enabled
EFI stub: ERROR: install_configuration_table() failed
error: start_image() returned 0x80000009.

Dropping to grub prompt for unknown reason. Should never get here.

One thing to note - If I boot into the kernel directly from u-boot, it boots fine & everything seems correct. AFAICT it seems that the problem only arises when uefi/grub are in the loop.
These u-boot commands let me boot into the kernel directly:

setenv bootargs "console=ttymxc0,115200n8 rootwait root=/dev/mmcblk0p2"
load mmc 0:2 ${loadaddr} boot/zImage
load mmc 0:2 ${fdt_addr_r} boot/imx6ull-var-som-emmc-sd-card.dtb
bootz ${loadaddr} - ${fdt_addr_r}

Also, perhaps unsurprisingly, if I overwrite the zImage with one from the Zeus build (kernel 5.4.3-imx6ul+g9447bf00ed07), it boots fine.
And the opposite is true too - if I use an SD card with the Zeus build, and overwrite the zImage with one from Scarthgap, I get the exact same install_configuration_table & start_image errors.
To me, that indicates that the bootloaders are OK, and that the issue is the kernel itself - or at least, the handoff done via u-boot/grub.

Any help or guidance on how to proceed would be greatly appreciated. I’m guessing its a kernel configuration issue, however I think the config is correct. Here are the efi options in the kernel config, if it’s relevant:

root@imx6ul-var-dart-ts:~# zcat /proc/config.gz   | grep -i efi
CONFIG_EFI_STUB=y
CONFIG_EFI=y
CONFIG_EFI_PARTITION=y
# EFI (Extensible Firmware Interface) Support
CONFIG_EFI_ESRT=y
CONFIG_EFI_PARAMS_FROM_FDT=y
CONFIG_EFI_RUNTIME_WRAPPERS=y
CONFIG_EFI_GENERIC_STUB=y
CONFIG_EFI_ARMSTUB_DTB_LOADER=y
# CONFIG_EFI_BOOTLOADER_CONTROL is not set
# CONFIG_EFI_CAPSULE_LOADER is not set
# CONFIG_EFI_TEST is not set
# CONFIG_EFI_DISABLE_PCI_DMA is not set
# CONFIG_EFI_DISABLE_RUNTIME is not set
# CONFIG_EFI_COCO_SECRET is not set
# end of EFI (Extensible Firmware Interface) Support
# Software defined radio USB devices
# CONFIG_FB_EFI is not set
# CONFIG_RTC_DRV_EFI is not set
CONFIG_EFIVAR_FS=m

7 posts - 2 participants