Sebastian Reichel writes: > Hi, > > On Tue, Jun 02, 2020 at 11:49:08AM +0200, Lars Povlsen wrote: > > Rob Herring writes: > > > On Wed, May 13, 2020 at 03:08:40PM +0200, Lars Povlsen wrote: > > >> This documents the 'microchip,reset-switch-core' property in the > > >> ocelot-reset driver. > > >> > > >> Signed-off-by: Lars Povlsen <lars.povlsen@xxxxxxxxxxxxx> > > >> --- > > >> .../devicetree/bindings/power/reset/ocelot-reset.txt | 6 ++++++ > > >> 1 file changed, 6 insertions(+) > > >> > > >> diff --git a/Documentation/devicetree/bindings/power/reset/ocelot-rese= > t.txt b/Documentation/devicetree/bindings/power/reset/ocelot-reset.txt > > >> index 4d530d8154848..20fff03753ad2 100644 > > >> --- a/Documentation/devicetree/bindings/power/reset/ocelot-reset.txt > > >> +++ b/Documentation/devicetree/bindings/power/reset/ocelot-reset.txt > > >> @@ -9,9 +9,15 @@ microchip Sparx5 armv8 SoC's. > > >> Required Properties: > > >> - compatible: "mscc,ocelot-chip-reset" or "microchip,sparx5-chip-res= > et" > > >> > > >> +Optional properties: > > >> +- microchip,reset-switch-core : Perform a switch core reset at the > > >> + time of driver load. This is may be used to initialize the switch > > >> + core to a known state (before other drivers are loaded). > > > > > > How do you know when other drivers are loaded? This could be a module > > > perhaps. Doesn't seem like something that belongs in DT. > > > > > > > The reset driver is loaded at postcore_initcall() time, which ensures it > > is loaded before other drivers using the switch core. I noticed other > > drivers do the same to do low-level system reset and initialization at > > early boot time. > > > > > Can this behavior be implied with "microchip,sparx5-chip-reset"? > > > > Since we need to cater for both modus operandi, I would need two driver > > compatible strings per platform, which scales worse than a single > > property. > > > > The "microchip,reset-switch-core" is a device configuration property > > which tells the system (driver) how the hw should be handled. Since you > > do not *always* want to reset the switch core (f.ex. when implementing > > systems with warm reboot), I think it makes perfect sense - but I may be > > biased off course :-) > > > > Thank you for (all) of your comments, by the way! > > > > ---Lars > > > Rob > > Is this series still needed? Did I miss a follow-up? Hi Sebastian! Yes, the series is still needed, but the conversation died after my last message. If the DT-controlled reset property is too controversial, I am willing to drop that part. (Rob just reviewed the bindings). MCHP reference designs have GPIO resets, so we *could* get by without, but new designs may this feature. > -- Sebastian ---Lars -- Lars Povlsen, Microchip
