On 20/06/17 17:20, Florian Fainelli wrote: > On 06/20/2017 02:10 AM, Lorenzo Pieralisi wrote: >> [+Sudeep] >> >> On Mon, Jun 19, 2017 at 10:32:38AM -0700, Florian Fainelli wrote: >>> On 06/19/2017 05:24 AM, Mark Rutland wrote: >>>> On Fri, Jun 16, 2017 at 05:07:40PM -0700, Florian Fainelli wrote: >>>>> Hi all, >>>> >>>> Hi Florian, >>>> >>>>> This patch series makes ARM's fncpy() implementation more generic (dropping the >>>>> Thumb-specifics) and available in an asm-generic header file. >>>>> >>>>> Tested on a Broadcom ARM64 STB platform with code that is written to SRAM. >>>>> >>>>> Changes in v3 (thanks Doug!): >>>>> - correct include guard names in asm-generic/fncpy.h to __ASM_FNCPY_H >>>>> - utilize Kbuild to provide the fncpy.h header on ARM64 >>>>> >>>>> Changes in v2: >>>>> - leave the ARM implementation where it is >>>>> - make the generic truly generic (no) >>>>> >>>>> This is helpful in making SoC-specific power management code become true drivers >>>>> that can be shared between different architectures. >>>>> Could you elaborate on what this is needed for? >>> >>> Several uses cases come to mind: >>> >>> - it could be used as a trampoline code prior to entering S2 for systems >>> that do not support PSCI 1.0 >> >> I think S2 here means PM_SUSPEND_MEM. It is very wrong to manage power >> states through platform specific hooks on PSCI based systems, consider >> upgrading to PSCI 1.0 please (or implement PSCI CPU_SUSPEND power >> states that allow to achieve same power savings as PM_SUSPEND_MEM >> by just entering suspend-to-idle). > > S2 is PM_SUSPEND_STANDBY and S3 is PM_SUSPEND_MEM, at least that how I > read it. I would rather we update to PSCI 1.0 (at least) to properly > support SYSTEM_SUSPEND rather than retrofitting a system-wide suspend > state into CPU_SUSPEND since that seems wrong. > This has been discussed multiple times in the past. No one has come back with strong reason to add that to the PSCI SYSTEM_SUSPEND API. Care to explain the difference between PM_SUSPEND_STANDBY and S3 is PM_SUSPEND_MEM on your platform. And why it can't be achieved with suspend-to-idle ? You can always report any issue with PSCI specification at errata@xxxxxxx as mentioned in the document. -- Regards, Sudeep
