Hi,

On Tue, Jun 02, 2020 at 11:49:08AM +0200, Lars Povlsen wrote:

Rob Herring writes:

quoted

On Wed, May 13, 2020 at 03:08:40PM +0200, Lars Povlsen wrote:

quoted

This documents the 'microchip,reset-switch-core' property in the
ocelot-reset driver.

Signed-off-by: Lars Povlsen <redacted>
---
 .../devicetree/bindings/power/reset/ocelot-reset.txt        | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/power/reset/ocelot-reset.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-reset"

+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.

quoted

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

quoted

Rob

Is this series still needed? Did I miss a follow-up?

-- Sebastian