Re: [PATCH v2] clk: keystone: sci-clk: Adding support for non contiguous clocks

[Kumar, Udit]

On 2/6/2024 9:24 PM, Kamlesh Gurudasani wrote:
> "Kumar, Udit" <u-kumar1@xxxxxx> writes:
>
> > > > > > get_freq is a bit expensive as it has to walk the clock tree to find
> > > > > > the clock frequency (at least the first time?). just wondering if
> > > > > > there is lighter alternative here?
> > > > > How about get_clock? Doesn't read the registers at least.
> > > > Said API needs, some flags to be passed,
> > > >
> > > > Can those flag be set to zero, Chandru ?
> > >
> > > get_clock doesn't require any flags to be passed.
> >
> > May be firmware does not need it but  I was referring to
> >
> > https://elixir.bootlin.com/linux/latest/source/drivers/clk/keystone/sci-clk.c#L78
> Just took a look,
>
> I now understand the reason for confusion,
>
> #define TI_SCI_MSG_SET_CLOCK_STATE	0x0100
> #define TI_SCI_MSG_GET_CLOCK_STATE	0x0101
>
> cops->get_clock = ti_sci_cmd_get_clock;  --> refers to
> TI_SCI_MSG_SET_CLOCK_STATE
> That's why we are passing the flag from linux for get_clock
>
> Linux is using terminology of get/put.
>
> As Chandru pointed, we don't have to pass flags, cause he is refering
> to TI_SCI_MSG_GET_CLOCK_STATE
>
> Below functions passes TI_SCI_MSG_GET_CLOCK_STATE to DM, which is what
> we actually want.
> cops->is_auto = ti_sci_cmd_clk_is_auto;
> cops->is_on = ti_sci_cmd_clk_is_on;
> cops->is_off = ti_sci_cmd_clk_is_off;


I think calling ti_sci_cmd_clk_is_auto should be good . other functions 
needs current state and requested state.

Chandru ?

> Which should be safe to call, Chandru can confirm.
>
> Regards,
> Kamlesh
> > > > > Regards,
> > > > > Kamlesh