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- Embedded device command line partition parsing
- =====================================================================
- Support for reading the block device partition table from the command line.
- It is typically used for fixed block (eMMC) embedded devices.
- It has no MBR, so saves 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)
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