Yocto EMMC Burning TI

Warning: This page is designed to be used with a 'release' URL parameter.

This page is using the default release am62-yocto-dunfell-5.10.168_08.06.00.42-v1.0.
To view this page for a specific Variscite SoM and software release, please follow these steps:

1. Visit variwiki.com
2. Select your SoM
3. Select the software release

Installing Yocto to the SOM's internal storage

Introduction

The VAR-SOM-AM62 can boot from an SD card or from internal storage.

The Variscite VAR-SOM-AM62 comes with eMMC, which holds U-Boot, the kernel image and the ext4 root file system.

eMMC structure

The eMMC has the following structure:

Offset Address	Offset (MiB)	Size	Partition	Description
0x0	0	1 MiB	Reserved	Reserved
0x100000	1 MiB	128 MiB	Boot	Boot partition containing U-Boot images
0x8600000	134 MiB	1 MiB	U-Boot Env	Reserved for U-Boot environment.
0x8700000	135 MiB	Rest of eMMC	rootfs	An ext4 partition containing the root file system (including Linux image and the device tree blobs under /boot

For example, an 16 GiB eMMC has the following layout:

root@am62x-var-som:~# fdisk -l /dev/mmcblk0
Disk /dev/mmcblk0: 14.69 GiB, 15758000128 bytes, 30777344 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xe3dbe120

Device         Boot  Start      End  Sectors  Size Id Type
/dev/mmcblk0p1 *      2048   264191   262144  128M  c W95 FAT32 (LBA)
/dev/mmcblk0p2      276480 30777343 30500864 14.6G 83 Linux

Installing the Yocto binaries

If you followed the Create a Recovery SD card steps, the Yocto binaries and the flashing scripts will be included in your SD card.

The flashing scripts are easy-to-use example scripts for flashing images into NAND flash / eMMC.

There is also a section below describing how to flash the images manually.