Rock/partitions

English

This page describe the partition layout of nand flash on radxa rock.

The partition is decided by the mtd parts in cmd line bootloader passed to the kernel, which is like this:

CMDLINE:console=ttyFIQ0 androidboot.console=ttyFIQ0 root=LABEL=linuxroot rw rootfstype=ext4 init=/sbin/init initrd=0x62000000,0x00800000 mtdparts=rk29xxnand:0x00002000@0x00002000(misc),0x00004000@0x00004000(kernel),0x00008000@0x00008000(boot),0x00010000@0x00010000(recovery),0x00020000@0x00020000(backup),0x00040000@0x00040000(cache),0x00200000@0x00080000(userdata),0x00002000@0x00280000(kpanic),0x00100000@0x00282000(system),0x00300000@0x00382000(linuxroot),-@0x00682000(user)

The partition must be 4M aligned due to the page size of rock/nand flash.

The layout of the dual boot image is as below:

Address	Size	Name	Description
0x000000400000-0x000000800000	4M	misc	Android misc partition
0x000000800000-0x000001800000	16M	kernel	Obsolete Linux kernel partition, not used, keep it for compatibility*
0x000001000000-0x000002000000	16M	boot	Android boot.img(kernel+ramdisk)
0x000002000000-0x000004000000	32M	recovery	Android recovery/ Linux kernel + ramdisk
0x000004000000-0x000008000000	64M	backup	Backup partition, not used on radxa rock, keep it for compatibility
0x000008000000-0x000010000000	128M	cache	Android /cache partition
0x000010000000-0x000050000000	1024M	userdata	Android /data partition
0x000050000000-0x000050400000	4M	kpanic	For kernel panic dump
0x000050400000-0x000070400000	512M	system	Android /system partition
0x000070400000-0x0000d0400000	1536M	linuxroot	For the Linux rootfs
0x0000d0400000-	-	user	Android internal flash as sdcard for storage

In previous android, the ramdisk(mounted as /) is in a separate partition, so we need two partitions, one for the kernel and the other for ramdisk, but the newer android pack together the kernel and the ramdisk into one single boot.img, so only one partition is needed