Hi Balaji, On 2026-08-11T05:18:35, Balaji Selvanathan <[email protected]> wrote: > doc: usage: reset: document device-tree-driven reset modes > > Document the "reset -<mode>" and "reset -l" forms and explain that named > reset modes are declared in the device tree (a "reboot-mode" subnode of the > psci node) rather than hardcoded per SoC. Describe the 1-to-3 cell > mode-<name> encoding and note that U-Boot's 32-bit PSCI cookie means a > 3-cell mode with a non-zero cookie_hi is rejected rather than truncated. > > Signed-off-by: Balaji Selvanathan <[email protected]> > > doc/usage/cmd/reset.rst | 42 ++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 42 insertions(+)
> diff --git a/doc/usage/cmd/reset.rst b/doc/usage/cmd/reset.rst > @@ -22,6 +24,46 @@ DDR and peripherals, on some boards also resets external > PMIC. > +Each ``mode-<name>`` property carries 1 to 3 cells describing a PSCI > +``SYSTEM_RESET2`` vendor reset: ``<reset_type[, cookie_hi[, cookie_lo]]>``. > +``reset_type`` must have bit 31 set (the vendor-reset bit). With two cells > the > +second is the cookie; with three cells the second is the high half and the > +third the low half of a 64-bit cookie. 'must have bit 31 set' overstates what U-Boot does - psci_system_reset2() in arch/arm/cpu/armv8/fwcall.c ORs PSCI_RESET2_TYPE_VENDOR in unconditionally, and reboot-mode-psci does not check or reject a reset_type with bit 31 clear. Either soften this to something like 'is the SYSTEM_RESET2 reset_type from the PSCI spec, with bit 31 (vendor-reset) set for the current users', or add a check in the PSCI driver so the doc matches the code. > diff --git a/doc/usage/cmd/reset.rst b/doc/usage/cmd/reset.rst > @@ -22,6 +24,46 @@ DDR and peripherals, on some boards also resets external > PMIC. > +-<mode> > + Reset into a named mode registered with the reboot-mode framework, for > + example ``reset -edl`` to enter Qualcomm EDL/download mode. The modes are > + described in the device tree, not hardcoded per SoC (see below); an > + unknown mode prints the list of available modes. Since this patch changes the command's exit behaviour (unknown mode returns CMD_RET_USAGE, 'reset -l' can return CMD_RET_FAILURE), please also update the 'Return value' section - it still claims '$? is always set to 0 (true)', which is no longer true once this series lands. Regards, Simon
