A rather common kind of external watchdog circuit is one that is kept
alive by toggling a gpio. Add a driver for handling such a watchdog.
The corresponding linux driver apparently has support for some
watchdog circuits which can be disabled by tri-stating the gpio, but I
have never actually encountered such a chip in the wild; the whole
point of adding an external watchdog is usually that it is not in any
way under software control. For forward-compatibility, and to make DT
describe the hardware, the current driver only supports devices that
have the always-running property. I went a little back and forth on
whether I should fail ->probe or only ->start, and ended up deciding
->start was the right place.
The compatible string is probably a little odd as it has nothing to do
with linux per se - however, I chose that to make .dts snippets
reusable between device trees used with U-Boot and linux, and this is
the (only) compatible string that linux' corresponding driver and DT
binding accepts. I have asked whether one should/could add "wdt-gpio"
to that binding, but the answer was no:
https://lore.kernel.org/lkml/CAL_JsqKEGaFpiFV_oAtE+S_bnHkg4qry+bhx2EDs=NSbVf_giA@mail.gmail.com/
If someone feels strongly about this, I can certainly remove the
"linux," part from the string - it probably wouldn't the only place where
one can't reuse a DT snippet as-is between linux and U-Boot.
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
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.
2ac8490412