[PATCH 09/10] doc: cmd: add documentation for scmi

[AKASHI Takahiro]

This is a help text for scmi command.

Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
---
 doc/usage/cmd/scmi.rst | 98 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 98 insertions(+)
 create mode 100644 doc/usage/cmd/scmi.rst

diff --git a/doc/usage/cmd/scmi.rst b/doc/usage/cmd/scmi.rst
new file mode 100644
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+.. SPDX-License-Identifier: GPL-2.0+:
+
+scmi command
+============
+
+Synopsis
+--------
+
+::
+
+    scmi base info
+    scmi base perm_dev <agent id> <device id> <flags>
+    scmi base perm_proto <agent id> <device id> <command id> <flags>
+    scmi base reset <agent id> <flags>
+
+Description
+-----------
+
+The scmi command is used to access and operate on SCMI server.
+
+scmi base info
+~~~~~~~~~~~~~~
+    Show base information about SCMI server and supported protocols
+
+scmi base perm_dev
+~~~~~~~~~~~~~~~~~~
+    Allow or deny access permission to the device
+
+scmi base perm_proto
+~~~~~~~~~~~~~~~~~~~~
+    Allow or deny access to the protocol on the device
+
+scmi base reset
+~~~~~~~~~~~~~~~
+    Reset the existing configurations
+
+Parameters are used as follows:
+
+<agent id>
+    Agent ID
+
+<device id>
+    Device ID
+
+<command id>
+    Protocol ID, should not be 0x10 (base protocol)
+
+<flags>
+    Flags to control the action. See SCMI specification for
+    defined values.
+
+Example
+-------
+
+Obtain basic information about SCMI server:
+
+::
+
+    => scmi base info
+    SCMI device: scmi
+      protocol version: 0x20000
+      # of agents: 3
+          0: platform
+        > 1: OSPM
+          2: PSCI
+      # of protocols: 4
+          Power domain management
+          Performance domain management
+          Clock management
+          Sensor management
+      vendor: Linaro
+      sub vendor: PMWG
+      impl version: 0x20b0000
+
+Ask for access permission to device#0:
+
+::
+
+    => scmi base perm_dev 1 0 1
+
+Reset configurations with all access permission settings retained:
+
+::
+
+    => scmi base reset 1 0
+
+Configuration
+-------------
+
+The scmi command is only available if CONFIG_CMD_SCMI=y.
+Default n because this command is mainly for debug purpose.
+
+Return value
+------------
+
+The return value ($?) is set to 0 if the operation succeeded,
+1 if the operation failed or -1 if the operation failed due to
+a syntax error.
-- 
2.41.0