On 21/02/17 11:07, Pavel Machek wrote: > Hi! > >> Enable support for "shallow" suspend mode, also known as "Standby" or >> "Power-On Suspend". >> >> As secondary CPU cores are taken offline, "shallow" suspend mode saves >> slightly more power than "s2idle", but less than "deep" suspend mode. >> However, unlike "deep" suspend mode, "shallow" suspend mode can be used >> regardless of the presence of support for PSCI_SYSTEM_SUSPEND, which is >> an optional API in PSCI v1.0. > > If system supports "shallow" suspend, why does not PSCI implement it? > Yes it can, and IIUC it already does on this platform with CPU_SUSPEND. All it now needs is just to use existing "freeze" suspend mode in Linux. > In the past, I was told PSCI will not turn into ACPI-like mess, and > that we'll be able to fix PSCI and will not have to work around its > problems in kernel :-(. Can you be more elaborate on the mess you see on this Renesas platform. For me, it looks like this patch is attempting to *re-implement* the existing "suspend-to-idle" functionality. So IMO, this patch set is creating unnecessary mess giving an illusion that PSCI specification is broken. -- Regards, Sudeep
