Hi Nishanth, On 11/21/22 20:56, Nishanth Menon wrote: > On 20:13-20221116, Georgi Vlaev wrote: >> + /* >> + * Attempt to call prepare_sleep, this will be NAK'd if suspend is not >> + * supported by firmware in use, in which case we will not attempt to >> + * init suspend. >> + */ >> + ret = ti_sci_cmd_prepare_sleep(&info->handle, 0, >> + (u32)(info->ctx_mem_addr & 0xffffffff), >> + (u32)((u64)info->ctx_mem_addr >> 32), 0); >> + > > https://software-dl.ti.com/tisci/esd/latest/2_tisci_msgs/pm/lpm.html#tisci-msg-prepare-sleep > "Prepare the SOC for entering into a low power mode." > > But we are in the init process here. From the documentation, firmware > does'nt seem to guarantee it would do something unexpected (like setup > io daisy chain or something like that which normal LP entry state > would have to do) - How is it safe to use it as a discovery of > capability API? > > Well, you're correct, there's no guarantee. It is safe to call it now on AM62x in both places we actually use it. However, this may change in the future and it's not a good idea to misuse that API. We'll switch the detection part to a more appropriate message, that's better suited for this purpose on all K3 platforms. -- Regards, Georgi
