To use the first on-chip serial port at baud rate 115200, no parity, 8
bits, and no flow control.
- (*) root=/dev/<xxxx>
+ (*) root=<xxxx>
- This specifies the device upon which the root filesystem resides. For
- example:
+ This specifies the device upon which the root filesystem resides. It
+ may be specified by major and minor number, device path, or even
+ partition uuid, if supported. For example:
/dev/nfs NFS root filesystem
/dev/mtdblock3 Fourth RedBoot partition on the System Flash
+ PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF/PARTNROFF=1
+ first partition after the partition with the given UUID
+ 253:0 Device with major 253 and minor 0
+
+ Authoritative information can be found in
+ "Documentation/kernel-parameters.txt".
(*) rw
ro [KNL] Mount root device read-only on boot
root= [KNL] Root filesystem
+ See name_to_dev_t comment in init/do_mounts.c.
rootdelay= [KNL] Delay (in seconds) to pause before attempting to
mount the root filesystem
the first of these. You can find out all valid major numbers by
looking into include/linux/major.h.
+In addition to major and minor numbers, if the device containing your
+root partition uses a partition table format with unique partition
+identifiers, then you may use them. For instance,
+"root=PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF". It is also
+possible to reference another partition on the same device using a
+known partition UUID as the starting point. For example,
+if partition 5 of the device has the UUID of
+00112233-4455-6677-8899-AABBCCDDEEFF then partition 3 may be found as
+follows:
+ PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF/PARTNROFF=-2
+
+Authoritative information can be found in
+"Documentation/kernel-parameters.txt".
+
2.2) ro, rw
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