Hi Joshua,
On Wed, 23 Aug 2023 at 10:48, Joshua Watt jpewhacker@gmail.com wrote:
Adds initial documentation for the gpt command
Signed-off-by: Joshua Watt JPEWhacker@gmail.com
doc/usage/cmd/gpt.rst | 139 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 139 insertions(+) create mode 100644 doc/usage/cmd/gpt.rst
diff --git a/doc/usage/cmd/gpt.rst b/doc/usage/cmd/gpt.rst new file mode 100644 index 0000000000..ea2cf73a60 --- /dev/null +++ b/doc/usage/cmd/gpt.rst @@ -0,0 +1,139 @@ +.. SPDX-License-Identifier: GPL-2.0+
+gpt command +===========
+Synopsis +--------
+::
- gpt repair <interface> <device no>
- gpt write <interface> <device no> <partition string>
- gpt verify <interface> <device no> <partition string>
- gpt setenv <interface> <device no> <partition name>
- gpt enumerate <interface> <device no>
- gpt guid <interface> <device no> [<varname>]
- gpt read <interface> <device no> [<varname>]
- gpt swap <interface> <dev> <name1> <name2>
- gpt rename <interface> <dev> <part> <name>
+Description +-----------
+The gpt command lets users read, create, modify, or verify the GPT (GUID +Partition Table) partition layout.
+The syntax of the text description of the partition list is similar to
By 'text description' do you mean '<partition string>' ?
+the one used by the 'mbr' command.
OK, but I think you need to show the string as a list of semicolon-separated components (or whatever) and then describe them. As written, this is quite confusing.
+The partition list may start with a set of parameters for the whole disk:
+* uuid_disk (the UUID of the disk)
+Following the disk parameters, partitions are specified separated by a ';'. +Supported partition parameters are:
+* name (required) +* start (required, partition start offset in bytes) +* size (in bytes or '-' to expand it to the whole free area) +* bootable (boolean flag) +* uuid (partition UUID, optional if CONFIG_RANDOM_UUID=y is enabled) +* type (partition type GUID, requires CONFIG_PARTITION_TYPE_GUID=y)
+Here is an example how to create a 6 partitions, some of the predefined sizes:
+::
- => setenv gpt_parts 'uuid_disk=bec9fc2a-86c1-483d-8a0e-0109732277d7;
name=boot,start=4M,size=128M,bootable,type=EBD0A0A2-B9E5-4433-87C0-68B6B72699C7,name=rootfs,size=3072M,type=0FC63DAF-8483-4772-8E79-3D69D8477DE4;name=system-data,size=512M,type=0FC63DAF-8483-4772-8E79-3D69D8477DE4;name=[ext],size=-,type=0FC63DAF-8483-4772-8E79-3D69D8477DE4;name=user,size=-,type=0FC63DAF-8483-4772-8E79-3D69D8477DE4;name=modules,size=100M,type=0FC63DAF-8483-4772-8E79-3D69D8477DE4;name=ramdisk,size=8M,type=0FC63DAF-8483-4772-8E79-3D69D8477DE4- => gpt write mmc 0 $gpt_parts
Please use lower-case hex
+If 'uuid' is not specified, but CONFIG_RANDOM_UUID is enabled, a random UUID +will be generated for the partition
+The 'gpt verify' command returns 0 if the layout matches the one on the storage +device or 1 if not. To check if the layout on the MMC #0 storage device +matches the provided text description one has to issue following command:
+::
- => gpt verify mmc 0 $gpt_parts
+The verify sub-command is especially useful in the system update scripts:
+::
- => if gpt verify mmc 0 $gpt_parts; then
echo GPT layout needs to be updated...fi+The 'gpt write' command returns 0 on success write or 1 on failure.
+The 'gpt setenv' command will set a series of environment variables with +information about a particular partition. The variables are:
+* gpt_partition_addr (the starting offset of the partition, in hexadecimal blocks) +* gpt_partition_size (the size of the partition, in hexadecimal blocks) +* gpt_partition_name (the name of the partition) +* gpt_partition_entry (the partition number in the table, e.g. 1, 2, 3, etc.)
+To get the information about the partition named 'rootfs', issue the following +command:
+::
- => gpt setenv mmc 0 rootfs
- => echo ${gpt_partition_addr}
- 2000
- => echo ${gpt_partition_size}
- 14a000
- => echo ${gpt_partition_name}
- rootfs
- => echo ${gpt_partition_entry}
- 2
+The 'gpt enumerate' command will set the variable 'gpt_partition_list' with the +list of partition names on the device. For example:
+::
- => gpt enumerate
- => echo gpt_partition_list
- boot rootfs system-data [ext] user modules ramdisk
+The 'gpt guid' command will report the GUID of a disk. If 'varname' is +specified, the command will set the variable to the GUID, otherwise it will be +printed out. For example:
+::
- => gpt guid mmc 0
- bec9fc2a-86c1-483d-8a0e-0109732277d7
- => gpt guid mmc gpt_disk_uuid
- => echo ${gpt_disk_uuid}
- bec9fc2a-86c1-483d-8a0e-0109732277d7
+The 'gpt read' command will print out the current state of the GPT partition +table. If 'varname' is specified, the variable will be filled with a partition +string as described above that is suitable for passing to other 'gpt' commands. +If omitted, a human readable description is printed out. +CONFIG_CMD_GPT_RENAME=y is required.
+The 'gpt swap' command changes the names of all partitions that are named +'name1' to be 'name2', and all partitions named 'name2' to be 'name1'. +CONFIG_CMD_GPT_RENAME=y is required.
+The 'gpt rename' command renames all partitions named 'part' to be 'name1'. +CONFIG_CMD_GPT_RENAME=y is required.
+Configuration +-------------
+To use the 'gpt' command you must specify CONFIG_CMD_GPT=y. To enable 'gpt
+read', 'gpt swap' and 'gpt rename', you must specify CONFIG_CMD_GPT_RENAME=y.
2.33.0
Great docs thank you!
- Simon