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+Embedded device command line partition
+=====================================================================
+
+Read block device partition table from command line.
+The partition used for fixed block device (eMMC) embedded device.
+It is no MBR, save storage space. Bootloader can be easily accessed
+by absolute address of data on the block device.
+Users can easily change the partition.
+
+The format for the command line is just like mtdparts:
+
+blkdevparts=<blkdev-def>[;<blkdev-def>]
+ <blkdev-def> := <blkdev-id>:<partdef>[,<partdef>]
+ <partdef> := <size>[@<offset>](part-name)
+
+<blkdev-id>
+ block device disk name, embedded device used fixed block device,
+ it's disk name also fixed. such as: mmcblk0, mmcblk1, mmcblk0boot0.
+
+<size>
+ partition size, in bytes, such as: 512, 1m, 1G.
+
+<offset>
+ partition start address, in bytes.
+
+(part-name)
+ partition name, kernel send uevent with "PARTNAME". application can create
+ a link to block device partition with the name "PARTNAME".
+ user space application can access partition by partition name.
+
+Example:
+ eMMC disk name is "mmcblk0" and "mmcblk0boot0"
+
+ bootargs:
+ 'blkdevparts=mmcblk0:1G(data0),1G(data1),-;mmcblk0boot0:1m(boot),-(kernel)'
+
+ dmesg:
+ mmcblk0: p1(data0) p2(data1) p3()
+ mmcblk0boot0: p1(boot) p2(kernel)