This patch adds a new "extension" command, which aims at detecting
extension boards connected to the hardware platform, and apply the
Device Tree overlays that describe the hardware present on those
extension boards.
In order to enable this mechanism, board-specific code must implement
the extension_board_scan() function that fills in a linked list of
"struct extension", each describing one extension board. In addition,
the board-specific code must select the SUPPORT_EXTENSION_SCAN Kconfig
boolean.
Based on this:
- "extension scan" makes the generic code call the board-specific
extension_board_scan() function to retrieve the list of detected
extension boards.
- "extension list" allows to list the detected extension boards.
- "extension apply <number>|all" allows to apply the Device Tree
overlay(s) corresponding to one, or all, extension boards
The latter requires two environment variables to exist and set one variable
to run:
- extension_overlay_addr: the RAM address where to load the Device
Tree overlays
- extension_overlay_cmd: the U-Boot command to load one overlay.
Indeed, the location and mechanism to load DT overlays is very setup
specific.
- extension_overlay_name: set by the command: the name of the DT which
will be load during the execution.
When calling the command described in the extension_overlay_cmd
variable, the variable extension_overlay_name will be defined. So a
typical extension_overlay_cmd will look like this:
extension_overlay_cmd=load mmc 0:1 $extension_overlay_addr /boot/$extension_overlay_name
Here is an example on how to use it:
=> run loadfdt
=> fdt addr $fdtaddr
=> setenv extension_overlay_addr 0x1000
=> setenv extension_overlay_cmd 'load mmc 0:1 ${extension_overlay_addr} /boot/${extension_overlay_name}'
=> extension scan
Found 1 extension board(s).
=> extension apply 0
519 bytes read in 3 ms (168.9 KiB/s)
Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Reviewed-by: Maxime Ripard <maxime@cerno.tech>
This patch series adds support for ZFS listing and load to u-boot.
To Enable zfs ls and load commands, modify the board specific config file with
#define CONFIG_CMD_ZFS
Steps to test:
1. After applying the patch, zfs specific commands can be seen
in the boot loader prompt using
UBOOT #help
zfsload- load binary file from a ZFS file system
zfsls - list files in a directory (default /)
2. To list the files in zfs pool, device or partition, execute
zfsls <interface> <dev[:part]> [POOL/@/dir/file]
For example:
UBOOT #zfsls mmc 0:5 /rpool/@/usr/bin/
3. To read and load a file from an ZFS formatted partition to RAM, execute
zfsload <interface> <dev[:part]> [addr] [filename] [bytes]
For example:
UBOOT #zfsload mmc 2:2 0x30007fc0 /rpool/@/boot/uImage
References :
-- ZFS GRUB sources from Solaris GRUB-0.97
-- GRUB Bazaar repository
Jorgen Lundman <lundman at lundman.net> 2012.