[PATCH v2 5/5] doc:eficonfig: add description for UEFI Secure Boot Configuration

[Masahisa Kojima]

This commits add the description for the UEFI Secure Boot
Configuration through the eficonfig menu.

Signed-off-by: Masahisa Kojima <masahisa.kojima at linaro.org>
---
Newly created in v2

 doc/usage/cmd/eficonfig.rst | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/doc/usage/cmd/eficonfig.rst b/doc/usage/cmd/eficonfig.rst
index 340ebc80db..67c859964f 100644
--- a/doc/usage/cmd/eficonfig.rst
+++ b/doc/usage/cmd/eficonfig.rst
@@ -31,6 +31,9 @@ Change Boot Order
 Delete Boot Option
     Delete the UEFI Boot Option
 
+Secure Boot Configuration
+    Edit UEFI Secure Boot Configuration
+
 Configuration
 -------------
 
@@ -44,6 +47,16 @@ U-Boot console. In this case, bootmenu can be used to invoke "eficonfig"::
     CONFIG_USE_PREBOOT=y
     CONFIG_PREBOOT="setenv bootmenu_0 UEFI Maintenance Menu=eficonfig"
 
+UEFI specification requires that UEFI Secure Boot Configuration (especially
+for PK and KEK) is stored in non-volatile storage which is tamper resident.
+CONFIG_EFI_MM_COMM_TEE is mandatory to provide the secure storage in U-Boot.
+UEFI Secure Boot Configuration menu entry is enabled when the following
+options are enabled::
+
+    CONFIG_EFI_SECURE_BOOT=y
+    CONFIG_EFI_MM_COMM_TEE=y
+
+
 How to boot the system with newly added UEFI Boot Option
 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 
@@ -66,6 +79,15 @@ add "bootefi bootmgr" entry as a default or first bootmenu entry::
 
     CONFIG_PREBOOT="setenv bootmenu_0 UEFI Boot Manager=bootefi bootmgr; setenv bootmenu_1 UEFI Maintenance Menu=eficonfig"
 
+UEFI Secure Boot Configuration
+''''''''''''''''''''''''''''''
+
+User can enroll PK, KEK, db and dbx by selecting file.
+"eficonfig" command only accepts the signed EFI Signature List(s)
+with an authenticated header, typically ".auth" file.
+To clear the PK, KEK, db and dbx, user needs to enroll the null key
+signed by PK or KEK.
+
 See also
 --------
 * :doc:`bootmenu<bootmenu>` provides a simple mechanism for creating menus with different boot items
-- 
2.17.1