This documents the way U-Boot understands partitions specifications. This also updates the fastboot documentation for the changes in the previous commit.
Signed-off-by: Sean Anderson sean.anderson@seco.com Reviewed-by: Simon Glass sjg@chromium.org ---
Changes in v2: - Move partition documentation under doc/usage
doc/android/fastboot.rst | 4 ++++ doc/usage/index.rst | 1 + doc/usage/part.rst | 33 +++++++++++++++++++++++++++++++++ 3 files changed, 38 insertions(+) create mode 100644 doc/usage/part.rst
diff --git a/doc/android/fastboot.rst b/doc/android/fastboot.rst index 2877c3cbaa..7b6eff82b4 100644 --- a/doc/android/fastboot.rst +++ b/doc/android/fastboot.rst @@ -151,6 +151,10 @@ The device index starts from ``a`` and refers to the interface (e.g. USB controller, SD/MMC controller) or disk index. The partition index starts from ``1`` and describes the partition number on the particular device.
+Alternatively, partition types may be specified using :ref:`U-Boot's partition +syntax <partitions>`. This allows specifying partitions like ``0.1``, +``0#boot``, or ``:3``. The interface is always ``mmc``. + Writing Partition Table -----------------------
diff --git a/doc/usage/index.rst b/doc/usage/index.rst index fbb2c0481c..a22ace03e8 100644 --- a/doc/usage/index.rst +++ b/doc/usage/index.rst @@ -4,6 +4,7 @@ Use U-Boot .. toctree::
netconsole + part
Shell commands -------------- diff --git a/doc/usage/part.rst b/doc/usage/part.rst new file mode 100644 index 0000000000..e58b529147 --- /dev/null +++ b/doc/usage/part.rst @@ -0,0 +1,33 @@ +.. SPDX-License-Identifier: GPL-2.0+ +.. _partitions: + +Partitions +========== + +Many U-Boot commands allow specifying partitions like:: + + some_command <interface> devnum.hwpartnum:partnum + +or like:: + + some_command <interface> <devnum.hwpartnum#partname + +Where + + * ``interface`` is the device interface, like ``mmc`` or ``scsi``. For a full + list of supported interfaces, consult the ``if_typename_str`` array in + ``drivers/block/blk-uclass.c`` + * ``devnum`` is the device number. This defaults to 0. + * ``hwpartnum`` is the hardware partition number. This defaults to 0 (the user + partition on eMMC devices). + * ``partname`` is the partition name on GPT devices. Partitions do not have + names on MBR devices. + * ``partnum`` is the partition number, starting from 1. The partition number 0 + is special, and specifies that the whole device is to be used as one + "partition." + +If neither ``partname`` nor ``partnum`` is specified and there is a partition +table, then partition 1 is used. If there is no partition table, then the whole +device is used as one "partition." If none of ``devnum``, ``hwpartnum``, +``partnum``, or ``partname`` is specified, then ``devnum`` defaults to the value +of the ``bootdevice`` environmental variable.