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+.. SPDX-License-Identifier: GPL-2.0+
+.. Steven Stallion
+.. June 2013
+
+Plan 9
+======
+
+Plan 9 from Bell Labs kernel images require additional setup to pass
+configuration information to the kernel.  An environment variable named
+confaddr must be defined with the same value as CONFADDR (see mem.h).
+Use of this facility is optional, but should be preferable to manual
+configuration.
+
+When booting an image, arguments supplied to the bootm command will be
+copied to CONFADDR.  If no arguments are specified, the contents of the
+bootargs environment variable will be copied.
+
+If no command line arguments or bootargs are defined, CONFADDR is left
+uninitialized to permit manual configuration.  For example, PC-style
+configuration could be simulated by issuing a fatload in bootcmd::
+
+  # setenv bootcmd fatload mmc 0 $confaddr plan9.ini; ...; bootm