IMX6 Kernel Booting through Serial Download mode in Android Pie on a custom platform.

[ramakrishna_n]

Hello NXP Team,

I am working on a custom platform which has IMX6Q as SOC on it. The board is having eMMC(mmc1) and SDCard (mmc0) as storage devices. 

The bootconfig is set to boot out of SDCard and successful to boot with Android Pie that we took from the SABRESD sources of NXP.

Currently we have a requirement to load the u-boot from Serial Download mode and other Android images from the SDCARD which has been flashed with the script "fsl-sdcard-partition.sh"

The below are the steps that we are trying to make the device to boot as required.

• Booting the device with the SDCARD (bootconfig set to SDCARD)
• Stops at the u-boot prompt and issuing the command "=> bmode usb"
• Now the device is in serial download mode and issuing the below command in another prompt to boot u-boot out of serial download mode.
•             sudo uuu u-boot-imx6q.imx (not using u-boot-imx6q-vise-uuu.imx because of no "boota" command in u-boot)
• Stop the console at u-boot prompt, now the DDR is loaded with the u-boot from the serial boot.
• Issuing the below command to pick the android images from SDCARD.
•              "=>boota mmc0"
• Ideally it should boot as per my knowledge, but failing with the below errors
•         MMC: block number 0xdfe07f exceeds max(0x72c000)
         avb_slot_verify.c:667: ERROR: vbmeta: Error loading vbmeta data.

I was wondering if this approach is valid to exercise, and please let me know how can i achieve the desired method to boot.

Below are the serial console logs that captured while exercise the reqirement.

U-Boot 2018.03-00003-gf44fd44-dirty (Sep 10 2020 - 15:59:38 +0530)

CPU: Freescale i.MX6D rev1.3 at 792MHz
CPU: Extended Commercial temperature grade (-20C to 105C) at 45C
Reset cause: POR
Model: Mistral i.MX6 Quad VISE Platform
Board: MX6-VISE
DRAM: 1 GiB
PMIC: PFUZE100! DEV_ID=0x10 REV_ID=0x21
MMC: FSL_SDHC: 0, FSL_SDHC: 1
Loading Environment from MMC... OK
No panel detected: default to Hannstar-XGA
Display: Hannstar-XGA (1024x768)
In: serial
Out: serial
Err: serial
Mistral: 1411 flash target is MMC:0
Net:
Error: ethernet@02188000 address not set.
No ethernet found.
Fastboot: Normal
Normal Boot
Hit any key to stop autoboot: 0
=> printenv
baudrate=115200
board_name=VISE
board_rev=MX6Q
bootcmd=boota mmc0
bootdelay=3
ethprime=eth0
fastboot_dev=mmc0
fdt_high=0xffffffff
fdtcontroladdr=49f11fb0
initrd_high=0xffffffff
loadaddr=0x12000000
soc_type=imx6q
splashpos=m,m
tee=no

Environment size: 262/8188 bytes
=> mmc list
FSL_SDHC: 0 (SD)
FSL_SDHC: 1
=> bmode usb
resetting ...

### Booting from USB serial mode using command "sudo uuu u-boot-imx6q.imx" ###
U-Boot 2018.03-00003-gf44fd44-dirty (Sep 10 2020 - 15:59:38 +0530)

CPU: Freescale i.MX6D rev1.3 at 792MHz
CPU: Extended Commercial temperature grade (-20C to 105C) at 49C
Reset cause: POR
Model: Mistral i.MX6 Quad VISE Platform
Board: MX6-VISE
DRAM: 1 GiB
PMIC: PFUZE100! DEV_ID=0x10 REV_ID=0x21
MMC: FSL_SDHC: 0, FSL_SDHC: 1
Loading Environment from MMC... OK
No panel detected: default to Hannstar-XGA
Display: Hannstar-XGA (1024x768)
In: serial
Out: serial
Err: serial
Mistral: 1411 flash target is MMC:0
Net:
Error: ethernet@02188000 address not set.
No ethernet found.
GPT: last_usable_lba incorrect: DFFFDE > 72c000
GUID Partition Table Header signature is wrong: 0x0 != 0x5452415020494645
part_get_info_efi: *** ERROR: Invalid Backup GPT ***
Cannot find partition 6
do_raw_read failed, ret 1
read_bootctl, bcb_rw_block read failed
read command failed
Fastboot: Normal
Boot from USB for uuu
Hit any key to stop autoboot: 0
=> printenv
baudrate=115200
board_name=VISE
board_rev=MX6Q
bootcmd=fastboot 0
bootdelay=3
ethprime=eth0
fastboot_dev=mmc1
fdt_high=0xffffffff
fdtcontroladdr=49f11fb0
initrd_high=0xffffffff
loadaddr=0x12000000
soc_type=imx6q
splashpos=m,m
tee=no

Environment size: 262/8188 bytes
=> mmc list
FSL_SDHC: 0 (SD)
FSL_SDHC: 1 (eMMC)
=> mmc dev 0
switch to partitions #0, OK
mmc0 is current device
=> boota mmc0
MMC: block number 0xdfe07f exceeds max(0x72c000)
avb_slot_verify.c:667: ERROR: vbmeta: Error loading vbmeta data.

Regards,

Ramakrishna