1Update eMMC with Android firmware

Partition the eMMC for holding Android images by running:
```
=> setenv mmcdev 0
=> run partition_mmc_android
```

Check the partition table created on the eMMC by running an mmc part command:

=> mmc part 
Partition Map for MMC device 0  --   Partition Type: EFI 
Part  	Start LBA		End LBA		Name
      	Attributes
      	Type UUID
      	Partition UUID
1	0x00001000		0x00020fff	"android"	
 	attrs:  0x0000000000000000
      	type:   ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
	uuid:   43f1961b-ce4c-4e6c-8f22-2230c5d532bd
2    	0x00021000        	0x00040fff      "android2"
     	attrs:  0x0000000000000000
      	type:   ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
      	uuid:   f241b915-4241-47fd-b4de-ab5af832a0f6
3    	0x00041000        	0x00140fff      "system"
      	attrs:  0x0000000000000000
      	type:   ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
      	uuid:   1c606ef5-f1ac-43b9-9bb5-d5c578580b6b
4    	0x00141000        	0x00240fff      "system2"
      	attrs:  0x0000000000000000
 	type:   ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
	uuid:   c7d8648b-76f7-4e2b-b829-e95a83cc7b32
5   	0x00241000        	0x00250fff      "cache"
      	attrs:  0x0000000000000000
      	type:   ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
 	uuid:   ebae5694-6e56-497c-83c6-c4455e12d727
6    	0x00251000        	0x0075efff      "data"
      	attrs:  0x0000000000000000
      	type:   ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
      	uuid:   3845c9fc-e581-49f3-999f-86c9bab515ef

As shown above, five partitions are created in anticipation of holding a redundant system:

android: To hold kernel, device tree and Android init ramdisk images.
android2: To hold a copy (or alternative) kernel, device tree and Android init ramdisk images.
system: To hold Android's root file system.
system2: To hold a copy (or alternative) Android's root file system.
cache: To hold Android cache.
data: To hold user data.

Write the file boot.img to eMMC partition android from TFTP or a FAT formatted microSD card:
- From TFTP (assuming the file is on the TFTP server's exposed folder):
```
=> update android tftp boot.img
```
- From a FAT formatted microSD card (where you previously copied the file):
```
=> update android mmc 1 fat boot.img
```
- Write the file system.img to eMMC partition system either:
- From TFTP (assuming the file is on the TFTP server's exposed folder):
```
=> update system tftp system.img
```
- From a FAT formatted microSD card (where you previously copied the file):
```
=> update system mmc 1 fat system.img
```

The new firmware is now ready on the eMMC. Default video output is HDMI.

Change the default boot command in U-Boot, set the system to perform a factory reset and to boot from eMMC:

=> setenv bootcmd dboot android mmc
=> bootargs_once="androidboot.cache=format androidboot.data=format"
=> saveenv

Note If the cache and data partitions are already formatted and you want to preserve their contents, you can skip the bootargs_once command.

Boot the device by executing this command:

=> boot