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
| . | SPL | IMG | ... | ENV1 | ... | ENV2 | ... |
- Linux device: /dev/mmcblk2boot0
| Offset (blocks) | Offset (bytes) | Size (bytes) | Comment |
|---|---|---|---|
| 0 | 0 | 1 KB (0x400) | Free |
| 0x02 | 1 KB (0x400) | 68 KB | U-Boot SPL (apf6-u-boot.spl) |
| 0x8a | 69 KB (0x11400) | 512 KB | U-Boot IMG (apf6-u-boot.img) |
| Free | |||
| 0x800 (2048) | 1024 KB (0x100000) | 10 KB (0x2800) | U-Boot environment |
| Free | |||
| 0xc00 (3072) | 1536 KB (0x180000) | 10 KB (0x2800) | Redundant U-Boot environment |
| Free |
User Data partition layout
There are two primary partitions on the "User Data" physical partition:
| ... | Boot | Rootfs |
| Name | U-Boot device | Linux device | Offset (bytes) | Offset (blocks) | Size | Comment |
|---|---|---|---|---|---|---|
| MBR | NA | NA | 0 | 0 | 512 bytes (1 block) | Master Boot Record. (Don't touch it :-) ) |
| ... | NA | NA | 512 | 1 | ~1 MBytes (2047 blocks) | Free |
| Boot | mmc 0:1 | /dev/mmcblk2p1 | 1M (0x100000) | 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 | 25M (0x1900000) | 51200 (0xc800) | Rest of space (< 7682048 blocks) | the rootfs is on this partition (ext4 formatted) |
- By default, when flashed from U-Boot, rootfs and boot are only occupying the size of the .ext4 images used during flashing. If you want to increase the rootfs/boot size to all available free space then, after Linux has booted, use the following commands:
# resize2fs /dev/mmcblk2p1 # for Boot # resize2fs /dev/mmcblk2p2 # for Rootfs
Rootfs/Boot will then be extended to all the "Rootfs"/"Boot" eMMC partitions space.
