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| author | Ahmad Fatoum <a.fatoum@pengutronix.de> | 2020-09-28 16:45:07 +0200 |
|---|---|---|
| committer | Sascha Hauer <s.hauer@pengutronix.de> | 2020-09-29 10:25:02 +0200 |
| commit | b42bf25c5bd4baffac1a4f3b40ec0ba10cc13504 (patch) | |
| tree | 95bdbfff4e833b180677eb86184ce492e1272289 /Documentation/user/reboot-mode.rst | |
| parent | fc8511d20ab32a31e9502c54a28a3f7f55223f39 (diff) | |
| download | barebox-b42bf25c5bd4baffac1a4f3b40ec0ba10cc13504.tar.gz barebox-b42bf25c5bd4baffac1a4f3b40ec0ba10cc13504.tar.xz | |
power: reset: reboot-mode: port syscon-reboot-mode support
Reboot modes are one-shot information that should be valid for only a
single reset. Syscons that survive a warm reset are one way to implement
this. This is used by many BootROMs to allow falling into a recovery
mode on the next boot. This ports the Linux syscon-reboot-mode support.
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'Documentation/user/reboot-mode.rst')
| -rw-r--r-- | Documentation/user/reboot-mode.rst | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/Documentation/user/reboot-mode.rst b/Documentation/user/reboot-mode.rst index 1908da3ed2..9321d928f4 100644 --- a/Documentation/user/reboot-mode.rst +++ b/Documentation/user/reboot-mode.rst @@ -45,6 +45,17 @@ Reboot mode providers have priorities. The provider with the highest priority has its parameters aliased as ``$global.system.reboot_mode.prev`` and ``$global.system.reboot_mode.next``. +Reset +~~~~~ + +Reboot modes can be stored on a syscon wrapping general purpose registers +that survives warm resets. If the system instead did reset via an external +power management IC, the registers may lose their value. + +If such reboot mode storage is used, users must take care to use the correct +reset provider. In barebox, multiple reset providers may co-exist. They +``reset`` command allows listing and choosing a specific reboot mode. + Disambiguation ~~~~~~~~~~~~~~ |