[PATCH v4 5/5] dt-bindings: clock: ast2600: Add reset config for I3C
Jeremy Kerr
jk at codeconstruct.com.au
Wed Mar 1 17:54:50 AEDT 2023
Hi Joel,
> > So I'm not sure what that comment is supposed to signify as to what
> > qualifies as a "gate" in the context of a reset...
>
> This is poor documentation from the author of the clock driver,
Hah, not that guy again!
> which is me.
oh.
> We only expose the reset lines in the device tree for resets that are
> not associated with a clock line.
>
> This is done because the aspeed docs specify we do a dance when
> enabling an IP:
>
> 1. Place IP in reset
> 2. Enable clock
> 3. Delay
> 4. Release reset
>
> So we do this with the aspeed_g6_gates array. The rule is: any gate
> with a number in the rst column doesn't have that reset line exposed.
> That's what this cryptic comment in the header is warning about.
That makes sense, and means I can drop the explicit reset control from
the DTS, and then we don't need these definitions.
> This was documented to some extent in the original commit message for
> the 2400/2500 driver:
>
> https://git.kernel.org/torvalds/c/15ed8ce5f84e2b
>
> We could hoist that out and put it in the source file(s).
Awesome, thanks for the explanation - I'll add a patch to do so.
Cheers,
Jeremy
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