Hi, On Thu, Apr 11, 2019 at 05:49:36PM +0100, Sudeep Holla wrote: > On Thu, Apr 11, 2019 at 11:42:28AM +0000, Koskinen, Aaro (Nokia - FI/Espoo) > wrote: > > From: Sudeep Holla [[email protected]]: > > > static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd) > > > { > > > + if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) && > > > > I would omit the REBOOT_SOFT here. > > I included REBOOT_SOFT for 2 reasons: > 1. drivers/firmware/efi/reboot.c - efi_reboot treats WARM and SOFT reboots > same > 2. If the vendors specific reboots are added and handled in EFI, I assume it > will be categorised under REBOOT_SOFT. > > If that's wrong I can drop REBOOT_SOFT.
Not a big issue, but it's just unclear what SOFT means. WARM at least maps nicely to the PSCI spec. > > > + psci_system_reset2_supported) > > > + /* > > > + * reset_type[31] = 0 (architectural) > > > + * reset_type[30:0] = 0 (SYSTEM_WARM_RESET) > > > + * cookie = 0 (ignored by the implementation) > > > + */ > > > + invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, > > > 0); > > > + > > > invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0); > > > > Use else here, so that we fall back to system halt if SYSTEM_RESET2 fails. > > Will that not change current behaviour ? IOW, is that expected behaviour ? > I am not sure if halt can be prefer over cold reboot in absence of warm/soft > reboot when the system is request to reboot. From PSCI perspective, since > SYSTEM_RESET is mandatory I prefer that unless Linux has any restriction > on this behaviour. Hmm, so does it mean that even if firmware tells that SYSTEM_RESET2 is implemented it does not imply that SYSTEM_WARM_RESET is available? I.e. the firmware could choose to implement only some vendor-specific resets but not architectural ones. In that case, could we fall back to cold reset only if NOT_SUPPORTED is returned? My point is that if the warm reset fails unexpectedly, we should halt the system like we do if the cold reset fails. A.
