[PATCH 00/28] Initial implementation of bootmethod/bootflow

Simon Glass sjg at chromium.org
Thu Aug 19 05:45:33 CEST 2021


Bootmethod and bootflow provide a built-in way for U-Boot to automatically boot
an Operating System without custom scripting and other customisation:

  - bootmethod - a method to scan a device to find bootflows (owned by U-Boot)
  - bootflow - a description of how to boot (owned by the distro)

This series provides an initial implementation of these, enable to scan
for bootflows from MMC and Ethernet. The only bootflow supported is
distro boot, i.e. an extlinux.conf file included on a filesystem or
tftp server. It works similiarly to the existing script-based approach,
but is native to U-Boot.

With this we can boot on a Raspberry Pi 3 with just one command:

   bootflow scan -lb

which means to scan, listing (-l) each bootflow and trying to boot each
one (-b). The final patch shows this.

It is intended that this approach be expanded to support mechanisms other
than distro boot, including EFI-related ones. With a standard way to
identify boot devices, these features become easier. It also should
support U-Boot scripts, for backwards compatibility only.

The first patch of this series moves boot-related code out of common/ and
into a new boot/ directory. This helps to collect these related files
in one place, as common/ is quite large.

Like sysboot, this feature makes use of the existing PXE implementation.
Much of this series consists of cleaning up that code and refactoring it
into something closer to a module that can be called, teasing apart its
reliance on the command-line interpreter to access filesystems and the
like. Also it now uses function arguments and its own context struct
internally rather than environment variables, which is very hard to
follow. No core functional change is included in the included PXE patches.

For documentation, see the 'doc' patch.

There is quite a long list of future work included in the documentation.
One question is the choice of naming. Since this is a bootloader, should
we just call this a 'method' and a 'flow' ? The 'boot' prefix is already
shared by other commands like bootm, booti, etc.

The design is described here:

https://drive.google.com/file/d/1ggW0KJpUOR__vBkj3l61L2dav4ZkNC12/view?usp=sharing

The series is available at u-boot-dm/bmea-working



Simon Glass (28):
  Create a new boot/ directory
  pxe: Move API comments to the header files
  pxe: Use a context pointer
  pxe: Move do_getfile() into the context
  pxe: Add a userdata field to the context
  pxe: Tidy up the is_pxe global
  pxe: Move pxe_utils files
  pxe: Tidy up some comments in pxe_utils
  pxe: Tidy up code style a little in pxe_utils
  pxe: Move common parsing coding into pxe_util
  pxe: Clean up the use of bootfile
  pxe: Drop get_bootfile_path()
  lib: Add tests for simple_itoa()
  lib: Add a function to convert a string to a hex value
  pxe: Return the file size from the getfile() function
  pxe: Refactor sysboot to have one helper
  doc: Move distro boot doc to rST
  pxe: Allow calling the pxe_get logic directly
  bootmethod: Add the uclass and core implementation
  bootmethod: Add an implementation of distro boot
  bootmethod: Add a command
  bootflow: Add a command
  bootmethod: Add tests for bootmethod and bootflow
  bootmethod: doc: Add documentation
  mmc: Allow for children other than the block device
  mmc: Add a bootmethod
  ethernet: Add a bootmethod
  RFC: rpi: Switch over to use bootflow

 Kconfig                                   |   2 +
 MAINTAINERS                               |  16 +
 Makefile                                  |   3 +-
 README                                    |   1 +
 common/Kconfig.boot => boot/Kconfig       |  22 +-
 boot/Makefile                             |  39 ++
 {common => boot}/android_ab.c             |   0
 {common => boot}/boot_fit.c               |   0
 {common => boot}/bootm.c                  |   0
 {common => boot}/bootm_os.c               |   0
 boot/bootmethod.c                         | 485 ++++++++++++++++++++
 {common => boot}/bootretry.c              |   0
 {common => boot}/common_fit.c             |   0
 boot/distro.c                             | 194 ++++++++
 {common => boot}/fdt_region.c             |   0
 {common => boot}/image-android-dt.c       |   0
 {common => boot}/image-android.c          |   0
 {common => boot}/image-cipher.c           |   0
 {common => boot}/image-fdt.c              |   0
 {common => boot}/image-fit-sig.c          |   0
 {common => boot}/image-fit.c              |   0
 {common => boot}/image-sig.c              |   0
 {common => boot}/image.c                  |   0
 {cmd => boot}/pxe_utils.c                 | 512 +++++++++++-----------
 cmd/Kconfig                               |   8 +
 cmd/Makefile                              |   5 +-
 cmd/bootflow.c                            | 399 +++++++++++++++++
 cmd/bootmethod.c                          | 130 ++++++
 cmd/pxe.c                                 | 136 +++---
 cmd/pxe_utils.h                           |  91 ----
 cmd/sysboot.c                             | 114 +++--
 common/Kconfig                            |   2 -
 common/Makefile                           |  22 -
 configs/sandbox_defconfig                 |   3 +-
 doc/android/boot-image.rst                |   2 +-
 doc/develop/bootflow.rst                  | 323 ++++++++++++++
 doc/{README.distro => develop/distro.rst} | 180 ++++----
 doc/develop/index.rst                     |   2 +
 doc/device-tree-bindings/bootmethod.txt   |  14 +
 doc/usage/bootflow.rst                    | 419 ++++++++++++++++++
 doc/usage/bootmethod.rst                  | 138 ++++++
 doc/usage/index.rst                       |   2 +
 drivers/mmc/Makefile                      |   5 +
 drivers/mmc/mmc-uclass.c                  |  23 +-
 drivers/mmc/mmc_bootmethod.c              |  46 ++
 include/bootmethod.h                      | 357 +++++++++++++++
 include/configs/rpi.h                     |  37 +-
 include/distro.h                          |  62 +++
 include/dm/uclass-id.h                    |   1 +
 include/mmc.h                             |  12 +-
 include/pxe_utils.h                       | 253 +++++++++++
 include/test/suites.h                     |   2 +
 include/vsprintf.h                        |  25 +-
 lib/vsprintf.c                            |  20 +-
 net/Kconfig                               |   9 +
 net/Makefile                              |   1 +
 net/eth-uclass.c                          |   8 +
 net/eth_bootmethod.c                      |  76 ++++
 scripts/Makefile.spl                      |   4 +-
 test/Makefile                             |   1 +
 test/boot/Makefile                        |   5 +
 test/boot/bootmethod.c                    | 271 ++++++++++++
 test/cmd_ut.c                             |   4 +
 test/print_ut.c                           |  33 ++
 tools/Makefile                            |  16 +-
 try.sh                                    | 131 ++++++
 66 files changed, 4035 insertions(+), 631 deletions(-)
 rename common/Kconfig.boot => boot/Kconfig (98%)
 create mode 100644 boot/Makefile
 rename {common => boot}/android_ab.c (100%)
 rename {common => boot}/boot_fit.c (100%)
 rename {common => boot}/bootm.c (100%)
 rename {common => boot}/bootm_os.c (100%)
 create mode 100644 boot/bootmethod.c
 rename {common => boot}/bootretry.c (100%)
 rename {common => boot}/common_fit.c (100%)
 create mode 100644 boot/distro.c
 rename {common => boot}/fdt_region.c (100%)
 rename {common => boot}/image-android-dt.c (100%)
 rename {common => boot}/image-android.c (100%)
 rename {common => boot}/image-cipher.c (100%)
 rename {common => boot}/image-fdt.c (100%)
 rename {common => boot}/image-fit-sig.c (100%)
 rename {common => boot}/image-fit.c (100%)
 rename {common => boot}/image-sig.c (100%)
 rename {common => boot}/image.c (100%)
 rename {cmd => boot}/pxe_utils.c (74%)
 create mode 100644 cmd/bootflow.c
 create mode 100644 cmd/bootmethod.c
 delete mode 100644 cmd/pxe_utils.h
 create mode 100644 doc/develop/bootflow.rst
 rename doc/{README.distro => develop/distro.rst} (76%)
 create mode 100644 doc/device-tree-bindings/bootmethod.txt
 create mode 100644 doc/usage/bootflow.rst
 create mode 100644 doc/usage/bootmethod.rst
 create mode 100644 drivers/mmc/mmc_bootmethod.c
 create mode 100644 include/bootmethod.h
 create mode 100644 include/distro.h
 create mode 100644 include/pxe_utils.h
 create mode 100644 net/eth_bootmethod.c
 create mode 100644 test/boot/Makefile
 create mode 100644 test/boot/bootmethod.c
 create mode 100755 try.sh

-- 
2.33.0.rc1.237.g0d66db33f3-goog



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