Re: [PATCH RFC RFT 3/3] clk: introduce CLK_ENABLE_HAND_OFF flag

From: Maxime Coquelin
Date: Tue Aug 11 2015 - 07:37:22 EST


Hi Geert,

On 08/11/2015 12:11 PM, Geert Uytterhoeven wrote:
Hi Maxime,

On Tue, Aug 11, 2015 at 12:02 PM, Maxime Coquelin
<maxime.coquelin@xxxxxx> wrote:
How can we pass CLK_ENABLE_HAND_OFF flag to a specific clock on STi
platform?
Add the flag to the relevant clocks in the C code, e.g. in
clk_register_flexgen():

if (!strcmp(name, "clk-icn-cpu"))
init.flags |= CLK_ENABLE_HAND_OFF;
The main problem I see with this proposal

Could we imagine having a kind of "clocks-enable-hand-off" property we could
use in our clock controller DT node?
You can imagine doing "flex_flags |= CLK_ENABLE_HAND_OFF" in
st_of_flexgen_setup(), depending on the presence of such a property.
Exactly, this is what I was thinking about.


However, not disabling clocks is a software policy, not a hardware description,
so IMHO it doesn't belong in DT.

I disagree here because if these clocks get gated the system is dead, so I wouldn't call this a SW Policy.
Moreover, I don't see how this property is different from assigned-clock-parents and assigned-clock-rates properties, which have been accepted.

Thanks,
Maxime
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