APF6 EMMC
From ArmadeusWiki
APF6 eMMC layout
By default, the 4GB eMMC on APF6 board has 4 physical/hardware partitions:
Boot0 | Boot1 | RPMB | User Data |
Name | U-Boot name | Size | Comment |
---|---|---|---|
boot0 | mmc dev 0 1 | 2MBytes | U-Boot is installed on this partition |
boot1 | mmc dev 0 2 | 2MBytes | Not used |
rpmb | mmc dev 0 3 | 512KBytes | Not used |
User Data | mmc dev 0 0 | remaining space | Kernel, device tree and rootfs |
Boot0 partition layout
Offset (blocks) | Offset (bytes) | Comment |
---|---|---|
0 | 0 | |
0x02 | 1 KB | U-Boot SPL (apf6-u-boot.spl) |
0x8a | 69 KB | U-Boot IMG (apf6-u-boot.img) |
512 KB | ||
1024 KB | U-Boot environment | |
1536 KB | Redundant U-Boot environment |
User Data partition layout
There are two primary partitions on the "User Data" physical partition:
... | Boot | Rootfs |
Name | U-Boot device | Linux device | Offset (blocks) | Size | Comment |
---|---|---|---|---|---|
Boot | mmc 0:1 | /dev/mmcblk2p1 | 2048 (0x800) | 24 MBytes (49152 blocks) | The kernel and the device tree (inside a dtbs/ directory) are on this partition (ext4 formatted) |
Rootfs | mmc 0:2 | /dev/mmcblk2p2 | (0x18800) | Rest of space (<3816448 blocks) | the rootfs is on this partition (ext4 formatted) |
- By default rootfs is only occupying the size of the .ext4 image flashed with U-Boot. If you want to increase the rootfs available free space then, after Linux has booted, use the following command:
# resize2fs /dev/mmcblk2p2
Rootfs will then be extended to all the "Rootfs" eMMC partition space.