doc: Move UEFI under develop/

Much of the content here is useful only for development. Move it under
that section.

Signed-off-by: Simon Glass <[email protected]>
Reviewed-by: Heinrich Schuchardt <[email protected]>

4 files changed, 0 insertions, 928 deletions

diff --git a/doc/uefi/index.rst b/doc/uefi/index.rst
deleted file mode 100644
index b790a91f174..00000000000
--- a/doc/uefi/index.rst
+++ /dev/null
@@ -1,11 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0+
-
-Unified Extensible Firmware (UEFI)
-==================================
-
-.. toctree::
-   :maxdepth: 2
-
-   uefi.rst
-   u-boot_on_efi.rst
-   iscsi.rst
diff --git a/doc/uefi/iscsi.rst b/doc/uefi/iscsi.rst
deleted file mode 100644
index 51d38cde243..00000000000
--- a/doc/uefi/iscsi.rst
+++ /dev/null
@@ -1,184 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0+
-.. Copyright (c) 2018 Heinrich Schuchardt
-
-iSCSI booting with U-Boot and iPXE
-==================================
-
-Motivation
-----------
-
-U-Boot has only a reduced set of supported network protocols. The focus for
-network booting has been on UDP based protocols. A TCP stack and HTTP support
-are expected to be integrated in 2018 together with a wget command.
-
-For booting a diskless computer this leaves us with BOOTP or DHCP to get the
-address of a boot script. TFTP or NFS can be used to load the boot script, the
-operating system kernel and the initial file system (initrd).
-
-These protocols are insecure. The client cannot validate the authenticity
-of the contacted servers. And the server cannot verify the identity of the
-client.
-
-Furthermore the services providing the operating system loader or kernel are
-not the ones that the operating system typically will use. Especially in a SAN
-environment this makes updating the operating system a hassle. After installing
-a new kernel version the boot files have to be copied to the TFTP server
-directory.
-
-The HTTPS protocol provides certificate based validation of servers. Sensitive
-data like passwords can be securely transmitted.
-
-The iSCSI protocol is used for connecting storage attached networks. It
-provides mutual authentication using the CHAP protocol. It typically runs on
-a TCP transport.
-
-Thus a better solution than DHCP/TFTP/NFS boot would be to load a boot script
-via HTTPS and to download any other files needed for booting via iSCSI from the
-same target where the operating system is installed.
-
-An alternative to implementing these protocols in U-Boot is to use an existing
-software that can run on top of U-Boot. iPXE[1] is the "swiss army knife" of
-network booting. It supports both HTTPS and iSCSI. It has a scripting engine for
-fine grained control of the boot process and can provide a command shell.
-
-iPXE can be built as an EFI application (named snp.efi) which can be loaded and
-run by U-Boot.
-
-Boot sequence
--------------
-
-U-Boot loads the EFI application iPXE snp.efi using the bootefi command. This
-application has network access via the simple network protocol offered by
-U-Boot.
-
-iPXE executes its internal script. This script may optionally chain load a
-secondary boot script via HTTPS or open a shell.
-
-For the further boot process iPXE connects to the iSCSI server. This includes
-the mutual authentication using the CHAP protocol. After the authentication iPXE
-has access to the iSCSI targets.
-
-For a selected iSCSI target iPXE sets up a handle with the block IO protocol. It
-uses the ConnectController boot service of U-Boot to request U-Boot to connect a
-file system driver. U-Boot reads from the iSCSI drive via the block IO protocol
-offered by iPXE. It creates the partition handles and installs the simple file
-protocol. Now iPXE can call the simple file protocol to load GRUB[2]. U-Boot
-uses the block IO protocol offered by iPXE to fulfill the request.
-
-Once GRUB is started it uses the same block IO protocol to load Linux. Via
-the EFI stub Linux is called as an EFI application::
-
-                  +--------+         +--------+
-                  |        | Runs    |        |
-                  | U-Boot |========>| iPXE   |
-                  | EFI    |         | snp.efi|
-    +--------+    |        | DHCP    |        |
-    |        |<===|********|<========|        |
-    | DHCP   |    |        | Get IP  |        |
-    | Server |    |        | Address |        |
-    |        |===>|********|========>|        |
-    +--------+    |        | Response|        |
-                  |        |         |        |
-                  |        |         |        |
-    +--------+    |        | HTTPS   |        |
-    |        |<===|********|<========|        |
-    | HTTPS  |    |        | Load    |        |
-    | Server |    |        | Script  |        |
-    |        |===>|********|========>|        |
-    +--------+    |        |         |        |
-                  |        |         |        |
-                  |        |         |        |
-    +--------+    |        | iSCSI   |        |
-    |        |<===|********|<========|        |
-    | iSCSI  |    |        | Auth    |        |
-    | Server |===>|********|========>|        |
-    |        |    |        |         |        |
-    |        |    |        | Loads   |        |
-    |        |<===|********|<========|        |       +--------+
-    |        |    |        | GRUB    |        | Runs  |        |
-    |        |===>|********|========>|        |======>| GRUB   |
-    |        |    |        |         |        |       |        |
-    |        |    |        |         |        |       |        |
-    |        |    |        |         |        | Loads |        |
-    |        |<===|********|<========|********|<======|        |      +--------+
-    |        |    |        |         |        | Linux |        | Runs |        |
-    |        |===>|********|========>|********|======>|        |=====>| Linux  |
-    |        |    |        |         |        |       |        |      |        |
-    +--------+    +--------+         +--------+       +--------+      |        |
-                                                                      |        |
-                                                                      |        |
-                                                                      | ~ ~ ~ ~|
-
-Security
---------
-
-The iSCSI protocol is not encrypted. The traffic could be secured using IPsec
-but neither U-Boot nor iPXE does support this. So we should at least separate
-the iSCSI traffic from all other network traffic. This can be achieved using a
-virtual local area network (VLAN).
-
-Configuration
--------------
-
-iPXE
-~~~~
-
-For running iPXE on arm64 the bin-arm64-efi/snp.efi build target is needed::
-
-    git clone http://git.ipxe.org/ipxe.git
-    cd ipxe/src
-    make bin-arm64-efi/snp.efi -j6 EMBED=myscript.ipxe
-
-The available commands for the boot script are documented at:
-
-http://ipxe.org/cmd
-
-Credentials are managed as environment variables. These are described here:
-
-http://ipxe.org/cfg
-
-iPXE by default will put the CPU to rest when waiting for input. U-Boot does
-not wake it up due to missing interrupt support. To avoid this behavior create
-file src/config/local/nap.h:
-
-.. code-block:: c
-
-    /* nap.h */
-    #undef NAP_EFIX86
-    #undef NAP_EFIARM
-    #define NAP_NULL
-
-The supported commands in iPXE are controlled by an include, too. Putting the
-following into src/config/local/general.h is sufficient for most use cases:
-
-.. code-block:: c
-
-    /* general.h */
-    #define NSLOOKUP_CMD            /* Name resolution command */
-    #define PING_CMD                /* Ping command */
-    #define NTP_CMD                 /* NTP commands */
-    #define VLAN_CMD                /* VLAN commands */
-    #define IMAGE_EFI               /* EFI image support */
-    #define DOWNLOAD_PROTO_HTTPS    /* Secure Hypertext Transfer Protocol */
-    #define DOWNLOAD_PROTO_FTP      /* File Transfer Protocol */
-    #define DOWNLOAD_PROTO_NFS      /* Network File System Protocol */
-    #define DOWNLOAD_PROTO_FILE     /* Local file system access */
-
-Open-iSCSI
-~~~~~~~~~~
-
-When the root file system is on an iSCSI drive you should disable pings and set
-the replacement timer to a high value in the configuration file [3]::
-
-    node.conn[0].timeo.noop_out_interval = 0
-    node.conn[0].timeo.noop_out_timeout = 0
-    node.session.timeo.replacement_timeout = 86400
-
-Links
------
-
-* [1] https://ipxe.org - iPXE open source boot firmware
-* [2] https://www.gnu.org/software/grub/ -
-  GNU GRUB (Grand Unified Bootloader)
-* [3] https://github.com/open-iscsi/open-iscsi/blob/master/README -
-  Open-iSCSI README
diff --git a/doc/uefi/u-boot_on_efi.rst b/doc/uefi/u-boot_on_efi.rst
deleted file mode 100644
index c9a41bc919f..00000000000
--- a/doc/uefi/u-boot_on_efi.rst
+++ /dev/null
@@ -1,235 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0+
-.. Copyright (C) 2015 Google, Inc
-
-U-Boot on EFI
-=============
-This document provides information about U-Boot running on top of EFI, either
-as an application or just as a means of getting U-Boot onto a new platform.
-
-
-Motivation
-----------
-Running U-Boot on EFI is useful in several situations:
-
-- You have EFI running on a board but U-Boot does not natively support it
-  fully yet. You can boot into U-Boot from EFI and use that until U-Boot is
-  fully ported
-
-- You need to use an EFI implementation (e.g. UEFI) because your vendor
-  requires it in order to provide support
-
-- You plan to use coreboot to boot into U-Boot but coreboot support does
-  not currently exist for your platform. In the meantime you can use U-Boot
-  on EFI and then move to U-Boot on coreboot when ready
-
-- You use EFI but want to experiment with a simpler alternative like U-Boot
-
-
-Status
-------
-Only x86 is supported at present. If you are using EFI on another architecture
-you may want to reconsider. However, much of the code is generic so could be
-ported.
-
-U-Boot supports running as an EFI application for 32-bit EFI only. This is
-not very useful since only a serial port is provided. You can look around at
-memory and type 'help' but that is about it.
-
-More usefully, U-Boot supports building itself as a payload for either 32-bit
-or 64-bit EFI. U-Boot is packaged up and loaded in its entirety by EFI. Once
-started, U-Boot changes to 32-bit mode (currently) and takes over the
-machine. You can use devices, boot a kernel, etc.
-
-
-Build Instructions
-------------------
-First choose a board that has EFI support and obtain an EFI implementation
-for that board. It will be either 32-bit or 64-bit. Alternatively, you can
-opt for using QEMU [1] and the OVMF [2], as detailed below.
-
-To build U-Boot as an EFI application (32-bit EFI required), enable CONFIG_EFI
-and CONFIG_EFI_APP. The efi-x86_app config (efi-x86_app_defconfig) is set up
-for this. Just build U-Boot as normal, e.g.::
-
-   make efi-x86_app_defconfig
-   make
-
-To build U-Boot as an EFI payload (32-bit or 64-bit EFI can be used), enable
-CONFIG_EFI, CONFIG_EFI_STUB, and select either CONFIG_EFI_STUB_32BIT or
-CONFIG_EFI_STUB_64BIT. The efi-x86_payload configs (efi-x86_payload32_defconfig
-and efi-x86_payload32_defconfig) are set up for this. Then build U-Boot as
-normal, e.g.::
-
-   make efi-x86_payload32_defconfig (or efi-x86_payload64_defconfig)
-   make
-
-You will end up with one of these files depending on what you build for:
-
-* u-boot-app.efi - U-Boot EFI application
-* u-boot-payload.efi  - U-Boot EFI payload application
-
-
-Trying it out
--------------
-QEMU is an emulator and it can emulate an x86 machine. Please make sure your
-QEMU version is 2.3.0 or above to test this. You can run the payload with
-something like this::
-
-   mkdir /tmp/efi
-   cp /path/to/u-boot*.efi /tmp/efi
-   qemu-system-x86_64 -bios bios.bin -hda fat:/tmp/efi/
-
-Add -nographic if you want to use the terminal for output. Once it starts
-type 'fs0:u-boot-payload.efi' to run the payload or 'fs0:u-boot-app.efi' to
-run the application. 'bios.bin' is the EFI 'BIOS'. Check [2] to obtain a
-prebuilt EFI BIOS for QEMU or you can build one from source as well.
-
-To try it on real hardware, put u-boot-app.efi on a suitable boot medium,
-such as a USB stick. Then you can type something like this to start it::
-
-   fs0:u-boot-payload.efi
-
-(or fs0:u-boot-app.efi for the application)
-
-This will start the payload, copy U-Boot into RAM and start U-Boot. Note
-that EFI does not support booting a 64-bit application from a 32-bit
-EFI (or vice versa). Also it will often fail to print an error message if
-you get this wrong.
-
-
-Inner workings
---------------
-Here follow a few implementation notes for those who want to fiddle with
-this and perhaps contribute patches.
-
-The application and payload approaches sound similar but are in fact
-implemented completely differently.
-
-EFI Application
-~~~~~~~~~~~~~~~
-For the application the whole of U-Boot is built as a shared library. The
-efi_main() function is in lib/efi/efi_app.c. It sets up some basic EFI
-functions with efi_init(), sets up U-Boot global_data, allocates memory for
-U-Boot's malloc(), etc. and enters the normal init sequence (board_init_f()
-and board_init_r()).
-
-Since U-Boot limits its memory access to the allocated regions very little
-special code is needed. The CONFIG_EFI_APP option controls a few things
-that need to change so 'git grep CONFIG_EFI_APP' may be instructive.
-The CONFIG_EFI option controls more general EFI adjustments.
-
-The only available driver is the serial driver. This calls back into EFI
-'boot services' to send and receive characters. Although it is implemented
-as a serial driver the console device is not necessarilly serial. If you
-boot EFI with video output then the 'serial' device will operate on your
-target devices's display instead and the device's USB keyboard will also
-work if connected. If you have both serial and video output, then both
-consoles will be active. Even though U-Boot does the same thing normally,
-These are features of EFI, not U-Boot.
-
-Very little code is involved in implementing the EFI application feature.
-U-Boot is highly portable. Most of the difficulty is in modifying the
-Makefile settings to pass the right build flags. In particular there is very
-little x86-specific code involved - you can find most of it in
-arch/x86/cpu. Porting to ARM (which can also use EFI if you are brave
-enough) should be straightforward.
-
-Use the 'reset' command to get back to EFI.
-
-EFI Payload
-~~~~~~~~~~~
-The payload approach is a different kettle of fish. It works by building
-U-Boot exactly as normal for your target board, then adding the entire
-image (including device tree) into a small EFI stub application responsible
-for booting it. The stub application is built as a normal EFI application
-except that it has a lot of data attached to it.
-
-The stub application is implemented in lib/efi/efi_stub.c. The efi_main()
-function is called by EFI. It is responsible for copying U-Boot from its
-original location into memory, disabling EFI boot services and starting
-U-Boot. U-Boot then starts as normal, relocates, starts all drivers, etc.
-
-The stub application is architecture-dependent. At present it has some
-x86-specific code and a comment at the top of efi_stub.c describes this.
-
-While the stub application does allocate some memory from EFI this is not
-used by U-Boot (the payload). In fact when U-Boot starts it has all of the
-memory available to it and can operate as it pleases (but see the next
-section).
-
-Tables
-~~~~~~
-The payload can pass information to U-Boot in the form of EFI tables. At
-present this feature is used to pass the EFI memory map, an inordinately
-large list of memory regions. You can use the 'efi mem all' command to
-display this list. U-Boot uses the list to work out where to relocate
-itself.
-
-Although U-Boot can use any memory it likes, EFI marks some memory as used
-by 'run-time services', code that hangs around while U-Boot is running and
-is even present when Linux is running. This is common on x86 and provides
-a way for Linux to call back into the firmware to control things like CPU
-fan speed. U-Boot uses only 'conventional' memory, in EFI terminology. It
-will relocate itself to the top of the largest block of memory it can find
-below 4GB.
-
-Interrupts
-~~~~~~~~~~
-U-Boot drivers typically don't use interrupts. Since EFI enables interrupts
-it is possible that an interrupt will fire that U-Boot cannot handle. This
-seems to cause problems. For this reason the U-Boot payload runs with
-interrupts disabled at present.
-
-32/64-bit
-~~~~~~~~~
-While the EFI application can in principle be built as either 32- or 64-bit,
-only 32-bit is currently supported. This means that the application can only
-be used with 32-bit EFI.
-
-The payload stub can be build as either 32- or 64-bits. Only a small amount
-of code is built this way (see the extra- line in lib/efi/Makefile).
-Everything else is built as a normal U-Boot, so is always 32-bit on x86 at
-present.
-
-Future work
------------
-This work could be extended in a number of ways:
-
-- Add ARM support
-
-- Add 64-bit application support
-
-- Figure out how to solve the interrupt problem
-
-- Add more drivers to the application side (e.g. video, block devices, USB,
-  environment access). This would mostly be an academic exercise as a strong
-  use case is not readily apparent, but it might be fun.
-
-- Avoid turning off boot services in the stub. Instead allow U-Boot to make
-  use of boot services in case it wants to. It is unclear what it might want
-  though.
-
-Where is the code?
-------------------
-lib/efi
-	payload stub, application, support code. Mostly arch-neutral
-
-arch/x86/cpu/efi
-	x86 support code for running as an EFI application and payload
-
-board/efi/efi-x86_app/efi.c
-	x86 board code for running as an EFI application
-
-board/efi/efi-x86_payload
-	generic x86 EFI payload board support code
-
-common/cmd_efi.c
-	the 'efi' command
-
---
-Ben Stoltz, Simon Glass
-Google, Inc
-July 2015
-
-* [1] http://www.qemu.org
-* [2] http://www.tianocore.org/ovmf/
diff --git a/doc/uefi/uefi.rst b/doc/uefi/uefi.rst
deleted file mode 100644
index 5a67737c157..00000000000
--- a/doc/uefi/uefi.rst
+++ /dev/null
@@ -1,498 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0+
-.. Copyright (c) 2018 Heinrich Schuchardt
-
-UEFI on U-Boot
-==============
-
-The Unified Extensible Firmware Interface Specification (UEFI) [1] has become
-the default for booting on AArch64 and x86 systems. It provides a stable API for
-the interaction of drivers and applications with the firmware. The API comprises
-access to block storage, network, and console to name a few. The Linux kernel
-and boot loaders like GRUB or the FreeBSD loader can be executed.
-
-Development target
-------------------
-
-The implementation of UEFI in U-Boot strives to reach the requirements described
-in the "Embedded Base Boot Requirements (EBBR) Specification - Release v1.0"
-[2]. The "Server Base Boot Requirements System Software on ARM Platforms" [3]
-describes a superset of the EBBR specification and may be used as further
-reference.
-
-A full blown UEFI implementation would contradict the U-Boot design principle
-"keep it small".
-
-Building U-Boot for UEFI
-------------------------
-
-The UEFI standard supports only little-endian systems. The UEFI support can be
-activated for ARM and x86 by specifying::
-
-    CONFIG_CMD_BOOTEFI=y
-    CONFIG_EFI_LOADER=y
-
-in the .config file.
-
-Support for attaching virtual block devices, e.g. iSCSI drives connected by the
-loaded UEFI application [4], requires::
-
-    CONFIG_BLK=y
-    CONFIG_PARTITIONS=y
-
-Executing a UEFI binary
-~~~~~~~~~~~~~~~~~~~~~~~
-
-The bootefi command is used to start UEFI applications or to install UEFI
-drivers. It takes two parameters::
-
-    bootefi <image address> [fdt address]
-
-* image address - the memory address of the UEFI binary
-* fdt address - the memory address of the flattened device tree
-
-Below you find the output of an example session starting GRUB::
-
-    => load mmc 0:2 ${fdt_addr_r} boot/dtb
-    29830 bytes read in 14 ms (2 MiB/s)
-    => load mmc 0:1 ${kernel_addr_r} efi/debian/grubaa64.efi
-    reading efi/debian/grubaa64.efi
-    120832 bytes read in 7 ms (16.5 MiB/s)
-    => bootefi ${kernel_addr_r} ${fdt_addr_r}
-
-When booting from a memory location it is unknown from which file it was loaded.
-Therefore the bootefi command uses the device path of the block device partition
-or the network adapter and the file name of the most recently loaded PE-COFF
-file when setting up the loaded image protocol.
-
-Launching a UEFI binary from a FIT image
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-A signed FIT image can be used to securely boot a UEFI image via the
-bootm command. This feature is available if U-Boot is configured with::
-
-    CONFIG_BOOTM_EFI=y
-
-A sample configuration is provided as file doc/uImage.FIT/uefi.its.
-
-Below you find the output of an example session starting GRUB::
-
-    => load mmc 0:1 ${kernel_addr_r} image.fit
-    4620426 bytes read in 83 ms (53.1 MiB/s)
-    => bootm ${kernel_addr_r}#config-grub-nofdt
-    ## Loading kernel from FIT Image at 40400000 ...
-       Using 'config-grub-nofdt' configuration
-       Verifying Hash Integrity ... sha256,rsa2048:dev+ OK
-       Trying 'efi-grub' kernel subimage
-         Description:  GRUB EFI Firmware
-         Created:      2019-11-20   8:18:16 UTC
-         Type:         Kernel Image (no loading done)
-         Compression:  uncompressed
-         Data Start:   0x404000d0
-         Data Size:    450560 Bytes = 440 KiB
-         Hash algo:    sha256
-         Hash value:   4dbee00021112df618f58b3f7cf5e1595533d543094064b9ce991e8b054a9eec
-       Verifying Hash Integrity ... sha256+ OK
-       XIP Kernel Image (no loading done)
-    ## Transferring control to EFI (at address 404000d0) ...
-    Welcome to GRUB!
-
-See doc/uImage.FIT/howto.txt for an introduction to FIT images.
-
-Configuring UEFI secure boot
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-The UEFI specification[1] defines a secure way of executing UEFI images
-by verifying a signature (or message digest) of image with certificates.
-This feature on U-Boot is enabled with::
-
-    CONFIG_UEFI_SECURE_BOOT=y
-
-To make the boot sequence safe, you need to establish a chain of trust;
-In UEFI secure boot the chain trust is defined by the following UEFI variables
-
-* PK - Platform Key
-* KEK - Key Exchange Keys
-* db - white list database
-* dbx - black list database
-
-An in depth description of UEFI secure boot is beyond the scope of this
-document. Please, refer to the UEFI specification and available online
-documentation. Here is a simple example that you can follow for your initial
-attempt (Please note that the actual steps will depend on your system and
-environment.):
-
-Install the required tools on your host
-
-* openssl
-* efitools
-* sbsigntool
-
-Create signing keys and the key database on your host:
-
-The platform key
-
-.. code-block:: bash
-
-    openssl req -x509 -sha256 -newkey rsa:2048 -subj /CN=TEST_PK/ \
-            -keyout PK.key -out PK.crt -nodes -days 365
-    cert-to-efi-sig-list -g 11111111-2222-3333-4444-123456789abc \
-            PK.crt PK.esl;
-    sign-efi-sig-list -c PK.crt -k PK.key PK PK.esl PK.auth
-
-The key exchange keys
-
-.. code-block:: bash
-
-    openssl req -x509 -sha256 -newkey rsa:2048 -subj /CN=TEST_KEK/ \
-            -keyout KEK.key -out KEK.crt -nodes -days 365
-    cert-to-efi-sig-list -g 11111111-2222-3333-4444-123456789abc \
-            KEK.crt KEK.esl
-    sign-efi-sig-list -c PK.crt -k PK.key KEK KEK.esl KEK.auth
-
-The whitelist database
-
-.. code-block:: bash
-
-    openssl req -x509 -sha256 -newkey rsa:2048 -subj /CN=TEST_db/ \
-            -keyout db.key -out db.crt -nodes -days 365
-    cert-to-efi-sig-list -g 11111111-2222-3333-4444-123456789abc \
-            db.crt db.esl
-    sign-efi-sig-list -c KEK.crt -k KEK.key db db.esl db.auth
-
-Copy the \*.auth files to media, say mmc, that is accessible from U-Boot.
-
-Sign an image with one of the keys in "db" on your host
-
-.. code-block:: bash
-
-    sbsign --key db.key --cert db.crt helloworld.efi
-
-Now in U-Boot install the keys on your board::
-
-    fatload mmc 0:1 <tmpaddr> PK.auth
-    setenv -e -nv -bs -rt -at -i <tmpaddr>:$filesize PK
-    fatload mmc 0:1 <tmpaddr> KEK.auth
-    setenv -e -nv -bs -rt -at -i <tmpaddr>:$filesize KEK
-    fatload mmc 0:1 <tmpaddr> db.auth
-    setenv -e -nv -bs -rt -at -i <tmpaddr>:$filesize db
-
-Set up boot parameters on your board::
-
-    efidebug boot add 1 HELLO mmc 0:1 /helloworld.efi.signed ""
-
-Now your board can run the signed image via the boot manager (see below).
-You can also try this sequence by running Pytest, test_efi_secboot,
-on the sandbox
-
-.. code-block:: bash
-
-    cd <U-Boot source directory>
-    pytest.py test/py/tests/test_efi_secboot/test_signed.py --bd sandbox
-
-UEFI binaries may be signed by Microsoft using the following certificates:
-
-* KEK: Microsoft Corporation KEK CA 2011
-  http://go.microsoft.com/fwlink/?LinkId=321185.
-* db: Microsoft Windows Production PCA 2011
-  http://go.microsoft.com/fwlink/p/?linkid=321192.
-* db: Microsoft Corporation UEFI CA 2011
-  http://go.microsoft.com/fwlink/p/?linkid=321194.
-
-Using OP-TEE for EFI variables
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-Instead of implementing UEFI variable services inside U-Boot they can
-also be provided in the secure world by a module for OP-TEE[1]. The
-interface between U-Boot and OP-TEE for variable services is enabled by
-CONFIG_EFI_MM_COMM_TEE=y.
-
-Tianocore EDK II's standalone management mode driver for variables can
-be linked to OP-TEE for this purpose. This module uses the Replay
-Protected Memory Block (RPMB) of an eMMC device for persisting
-non-volatile variables. When calling the variable services via the
-OP-TEE API U-Boot's OP-TEE supplicant relays calls to the RPMB driver
-which has to be enabled via CONFIG_SUPPORT_EMMC_RPMB=y.
-
-[1] https://optee.readthedocs.io/ - OP-TEE documentation
-
-Executing the boot manager
-~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-The UEFI specification foresees to define boot entries and boot sequence via
-UEFI variables. Booting according to these variables is possible via::
-
-    bootefi bootmgr [fdt address]
-
-As of U-Boot v2020.10 UEFI variables cannot be set at runtime. The U-Boot
-command 'efidebug' can be used to set the variables.
-
-Executing the built in hello world application
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-A hello world UEFI application can be built with::
-
-    CONFIG_CMD_BOOTEFI_HELLO_COMPILE=y
-
-It can be embedded into the U-Boot binary with::
-
-    CONFIG_CMD_BOOTEFI_HELLO=y
-
-The bootefi command is used to start the embedded hello world application::
-
-    bootefi hello [fdt address]
-
-Below you find the output of an example session::
-
-    => bootefi hello ${fdtcontroladdr}
-    ## Starting EFI application at 01000000 ...
-    WARNING: using memory device/image path, this may confuse some payloads!
-    Hello, world!
-    Running on UEFI 2.7
-    Have SMBIOS table
-    Have device tree
-    Load options: root=/dev/sdb3 init=/sbin/init rootwait ro
-    ## Application terminated, r = 0
-
-The environment variable fdtcontroladdr points to U-Boot's internal device tree
-(if available).
-
-Executing the built-in self-test
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-An UEFI self-test suite can be embedded in U-Boot by building with::
-
-    CONFIG_CMD_BOOTEFI_SELFTEST=y
-
-For testing the UEFI implementation the bootefi command can be used to start the
-self-test::
-
-    bootefi selftest [fdt address]
-
-The environment variable 'efi_selftest' can be used to select a single test. If
-it is not provided all tests are executed except those marked as 'on request'.
-If the environment variable is set to 'list' a list of all tests is shown.
-
-Below you can find the output of an example session::
-
-    => setenv efi_selftest simple network protocol
-    => bootefi selftest
-    Testing EFI API implementation
-    Selected test: 'simple network protocol'
-    Setting up 'simple network protocol'
-    Setting up 'simple network protocol' succeeded
-    Executing 'simple network protocol'
-    DHCP Discover
-    DHCP reply received from 192.168.76.2 (52:55:c0:a8:4c:02)
-      as broadcast message.
-    Executing 'simple network protocol' succeeded
-    Tearing down 'simple network protocol'
-    Tearing down 'simple network protocol' succeeded
-    Boot services terminated
-    Summary: 0 failures
-    Preparing for reset. Press any key.
-
-The UEFI life cycle
--------------------
-
-After the U-Boot platform has been initialized the UEFI API provides two kinds
-of services:
-
-* boot services
-* runtime services
-
-The API can be extended by loading UEFI drivers which come in two variants:
-
-* boot drivers
-* runtime drivers
-
-UEFI drivers are installed with U-Boot's bootefi command. With the same command
-UEFI applications can be executed.
-
-Loaded images of UEFI drivers stay in memory after returning to U-Boot while
-loaded images of applications are removed from memory.
-
-An UEFI application (e.g. an operating system) that wants to take full control
-of the system calls ExitBootServices. After a UEFI application calls
-ExitBootServices
-
-* boot services are not available anymore
-* timer events are stopped
-* the memory used by U-Boot except for runtime services is released
-* the memory used by boot time drivers is released
-
-So this is a point of no return. Afterwards the UEFI application can only return
-to U-Boot by rebooting.
-
-The UEFI object model
----------------------
-
-UEFI offers a flexible and expandable object model. The objects in the UEFI API
-are devices, drivers, and loaded images. These objects are referenced by
-handles.
-
-The interfaces implemented by the objects are referred to as protocols. These
-are identified by GUIDs. They can be installed and uninstalled by calling the
-appropriate boot services.
-
-Handles are created by the InstallProtocolInterface or the
-InstallMultipleProtocolinterfaces service if NULL is passed as handle.
-
-Handles are deleted when the last protocol has been removed with the
-UninstallProtocolInterface or the UninstallMultipleProtocolInterfaces service.
-
-Devices offer the EFI_DEVICE_PATH_PROTOCOL. A device path is the concatenation
-of device nodes. By their device paths all devices of a system are arranged in a
-tree.
-
-Drivers offer the EFI_DRIVER_BINDING_PROTOCOL. This protocol is used to connect
-a driver to devices (which are referenced as controllers in this context).
-
-Loaded images offer the EFI_LOADED_IMAGE_PROTOCOL. This protocol provides meta
-information about the image and a pointer to the unload callback function.
-
-The UEFI events
----------------
-
-In the UEFI terminology an event is a data object referencing a notification
-function which is queued for calling when the event is signaled. The following
-types of events exist:
-
-* periodic and single shot timer events
-* exit boot services events, triggered by calling the ExitBootServices() service
-* virtual address change events
-* memory map change events
-* read to boot events
-* reset system events
-* system table events
-* events that are only triggered programmatically
-
-Events can be created with the CreateEvent service and deleted with CloseEvent
-service.
-
-Events can be assigned to an event group. If any of the events in a group is
-signaled, all other events in the group are also set to the signaled state.
-
-The UEFI driver model
----------------------
-
-A driver is specific for a single protocol installed on a device. To install a
-driver on a device the ConnectController service is called. In this context
-controller refers to the device for which the driver is installed.
-
-The relevant drivers are identified using the EFI_DRIVER_BINDING_PROTOCOL. This
-protocol has has three functions:
-
-* supported - determines if the driver is compatible with the device
-* start - installs the driver by opening the relevant protocol with
-  attribute EFI_OPEN_PROTOCOL_BY_DRIVER
-* stop - uninstalls the driver
-
-The driver may create child controllers (child devices). E.g. a driver for block
-IO devices will create the device handles for the partitions. The child
-controllers  will open the supported protocol with the attribute
-EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER.
-
-A driver can be detached from a device using the DisconnectController service.
-
-U-Boot devices mapped as UEFI devices
--------------------------------------
-
-Some of the U-Boot devices are mapped as UEFI devices
-
-* block IO devices
-* console
-* graphical output
-* network adapter
-
-As of U-Boot 2018.03 the logic for doing this is hard coded.
-
-The development target is to integrate the setup of these UEFI devices with the
-U-Boot driver model [5]. So when a U-Boot device is discovered a handle should
-be created and the device path protocol and the relevant IO protocol should be
-installed. The UEFI driver then would be attached by calling ConnectController.
-When a U-Boot device is removed DisconnectController should be called.
-
-UEFI devices mapped as U-Boot devices
--------------------------------------
-
-UEFI drivers binaries and applications may create new (virtual) devices, install
-a protocol and call the ConnectController service. Now the matching UEFI driver
-is determined by iterating over the implementations of the
-EFI_DRIVER_BINDING_PROTOCOL.
-
-It is the task of the UEFI driver to create a corresponding U-Boot device and to
-proxy calls for this U-Boot device to the controller.
-
-In U-Boot 2018.03 this has only been implemented for block IO devices.
-
-UEFI uclass
-~~~~~~~~~~~
-
-An UEFI uclass driver (lib/efi_driver/efi_uclass.c) has been created that
-takes care of initializing the UEFI drivers and providing the
-EFI_DRIVER_BINDING_PROTOCOL implementation for the UEFI drivers.
-
-A linker created list is used to keep track of the UEFI drivers. To create an
-entry in the list the UEFI driver uses the U_BOOT_DRIVER macro specifying
-UCLASS_EFI as the ID of its uclass, e.g::
-
-    /* Identify as UEFI driver */
-    U_BOOT_DRIVER(efi_block) = {
-        .name  = "EFI block driver",
-        .id    = UCLASS_EFI,
-        .ops   = &driver_ops,
-    };
-
-The available operations are defined via the structure struct efi_driver_ops::
-
-    struct efi_driver_ops {
-        const efi_guid_t *protocol;
-        const efi_guid_t *child_protocol;
-        int (*bind)(efi_handle_t handle, void *interface);
-    };
-
-When the supported() function of the EFI_DRIVER_BINDING_PROTOCOL is called the
-uclass checks if the protocol GUID matches the protocol GUID of the UEFI driver.
-In the start() function the bind() function of the UEFI driver is called after
-checking the GUID.
-The stop() function of the EFI_DRIVER_BINDING_PROTOCOL disconnects the child
-controllers created by the UEFI driver and the UEFI driver. (In U-Boot v2013.03
-this is not yet completely implemented.)
-
-UEFI block IO driver
-~~~~~~~~~~~~~~~~~~~~
-
-The UEFI block IO driver supports devices exposing the EFI_BLOCK_IO_PROTOCOL.
-
-When connected it creates a new U-Boot block IO device with interface type
-IF_TYPE_EFI, adds child controllers mapping the partitions, and installs the
-EFI_SIMPLE_FILE_SYSTEM_PROTOCOL on these. This can be used together with the
-software iPXE to boot from iSCSI network drives [4].
-
-This driver is only available if U-Boot is configured with::
-
-    CONFIG_BLK=y
-    CONFIG_PARTITIONS=y
-
-Miscellaneous
--------------
-
-Load file 2 protocol
-~~~~~~~~~~~~~~~~~~~~
-
-The load file 2 protocol can be used by the Linux kernel to load the initial
-RAM disk. U-Boot can be configured to provide an implementation with::
-
-    EFI_LOAD_FILE2_INITRD=y
-    EFI_INITRD_FILESPEC=interface dev:part path_to_initrd
-
-Links
------
-
-* [1] http://uefi.org/specifications - UEFI specifications
-* [2] https://github.com/ARM-software/ebbr/releases/download/v1.0/ebbr-v1.0.pdf -
-  Embedded Base Boot Requirements (EBBR) Specification - Release v1.0
-* [3] https://developer.arm.com/docs/den0044/latest/server-base-boot-requirements-system-software-on-arm-platforms-version-11 -
-  Server Base Boot Requirements System Software on ARM Platforms - Version 1.1
-* [4] :doc:`iscsi`
-* [5] :doc:`../driver-model/index`