doc: PXE: mention extlinux.conf and sysboot

These use the same format as PXE boot.

Signed-off-by: Fiona Klute <fiona.klute@gmx.de>
Cc: Tom Rini <trini@konsulko.com>

diff --git a/doc/usage/pxe.rst b/doc/usage/pxe.rst
index d23cd453227d356d7ff2712a18a1154663f58261..c2dc11f218d207164588cf9086a868969528e10d 100644 (file)
--- a/doc/usage/pxe.rst
+++ b/doc/usage/pxe.rst
@@ -1,19 +1,22 @@
 .. SPDX-License-Identifier: GPL-2.0+
    Copyright 2010-2011 Calxeda, Inc.
 
-PXE Boot
-========
+PXE Boot and extlinux.conf
+==========================
 
 The ``pxe`` commands provide a near subset of the functionality
 provided by the PXELINUX boot loader. This allows U-Boot based systems
 to be controlled remotely using the same PXE based techniques that
 many non U-Boot based servers use.
 
+The ``sysboot`` command and Extlinux boot method use the same file
+format as PXE boot for ``extlinux.conf``.
+
 Commands
 --------
 
 ``pxe get``
-        **syntax:** ``pxe get``
+        **Syntax:** ``pxe get``
 
        follows PXELINUX's rules for retrieving configuration files
        from a tftp server, and supports a subset of PXELINUX's config
@@ -30,7 +33,7 @@ Commands
        http://syslinux.zytor.com/wiki/index.php/Doc/pxelinux
 
 ``pxe boot``
-        **syntax:** ``pxe boot [pxefile_addr_r]``
+        **Syntax:** ``pxe boot [pxefile_addr_r]``
 
        Interprets a pxe file stored in memory.
 
@@ -40,6 +43,18 @@ Commands
        There are some environment variables that may need to be set,
        depending on conditions, see the Environment section below.
 
+``sysboot``
+        **Syntax:** ``sysboot [-p] <interface> <dev[:part]> <ext2|fat|any> [addr] [filename]``
+
+       Load and boot an ``extlinux.conf`` file from a local
+       filesystem. Paths in the ``extlinux.conf`` file (kernel,
+       initrd, FDT and overlays) will be interpreted within that
+       filesystem.
+
+       Example:
+
+       ``sysboot mmc 0.0:2 any ${pxefile_addr_r} /boot/extlinux.conf``
+
 Environment
 -----------