Re: [PATCH v4 3/3] arm64: dts: reset: add microchip sparx5 switch reset driver

Hi Rob,

On Fri, 2021-02-05 at 16:35 -0600, Rob Herring wrote:

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On Wed, Jan 20, 2021 at 09:19:21AM +0100, Steen Hegelund wrote:

quoted

This provides reset driver support for the Microchip Sparx5 PCB134
and
PCB135 reference boards.

This isn't a compatible change. You need an explanation why that's
okay
if that's intended.

I am not entirely sure that I get your point.

The change (adding the reset driver) is new, and it is optional (but
strongly recommended) for the  clients to use it, so will this be a
incompatible change?

I can certainly add a an explanation.  Would that be needed here in the
bindings, or where do you suggest?

quoted

Signed-off-by: Steen Hegelund <steen.hegelund@microchip.com>
---
 arch/arm64/boot/dts/microchip/sparx5.dtsi | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/boot/dts/microchip/sparx5.dtsi

b/arch/arm64/boot/dts/microchip/sparx5.dtsi
index 380281f312d8..4edbb9fcdce0 100644

--- a/arch/arm64/boot/dts/microchip/sparx5.dtsi
+++ b/arch/arm64/boot/dts/microchip/sparx5.dtsi

@@ -132,9 +132,17 @@ mux: mux-controller {

                      };
              };

-             reset@611010008 {
-                     compatible = "microchip,sparx5-chip-reset";
-                     reg = <0x6 0x11010008 0x4>;
+             gcb_ctrl: syscon@611010000 {
+                     compatible = "microchip,sparx5-gcb-syscon",
"syscon";
+                     reg = <0x6 0x11010000 0x10000>;
+             };
+
+             reset: reset-controller@0 {
+                     compatible = "microchip,sparx5-switch-reset";
+                     reg = <0x6 0x0 0x0>;

Your register length is 0?

quoted

+                     #reset-cells = <1>;
+                     cpu-syscon = <&cpu_ctrl>;

Can't you accomplish the same thing adding these to
"microchip,sparx5-chip-reset"? Or possibly as a child node.

Define nodes based on h/w blocks, not as containers of things you
happen
to want for some driver.

quoted

+                     gcb-syscon = <&gcb_ctrl>;
              };

              uart0: serial@600100000 {
--
2.29.2

Thanks for your comments

BR
Steen


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