Re: [PATCH 3/3] arm64: dts: ti: k3-j7200-mcu-wakeup: Split fss node up

Andrew Davis
2023-04-24T18:56:06Z

On 4/24/23 12:36 PM, Nishanth Menon wrote:
> fss node claims to be entirely a syscon node, but it is really two
> parts of it - one a syscon that controls the hbmc mux and a simple bus
> where ospi, hbmc peripherals are located. So model it accordingly by
> splitting the node up and using ti,j721e-system-controller to describe
> the syscon
>
> Signed-off-by: Nishanth Menon <nm@ti.com>
> ---
> .../boot/dts/ti/k3-j7200-mcu-wakeup.dtsi | 21 +++++++++++++------
> 1 file changed, 15 insertions(+), 6 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/ti/k3-j7200-mcu-wakeup.dtsi b/arch/arm64/boot/dts/ti/k3-j7200-mcu-wakeup.dtsi
> index b58a31371bf3..7653cb191be1 100644
> --- a/arch/arm64/boot/dts/ti/k3-j7200-mcu-wakeup.dtsi
> +++ b/arch/arm64/boot/dts/ti/k3-j7200-mcu-wakeup.dtsi
> @@ -338,18 +338,27 @@ mcu_spi2: spi@40320000 {
> status = "disabled";
> };
>
> - fss: syscon@47000000 {
> - compatible = "syscon", "simple-mfd";
> + hbmc_syscon: syscon@47000000 {
> + compatible = "ti,j721e-system-controller", "syscon", "simple-mfd";
> reg = <0x00 0x47000000 0x00 0x100>;
> - #address-cells = <2>;
> - #size-cells = <2>;
> - ranges;
> + #address-cells = <1>;
> + #size-cells = <1>;
> + ranges = <0x00 0x00 0x47000000 0x100>;
>
> - hbmc_mux: hbmc-mux {
> + hbmc_mux: mux-controller@4 {
> compatible = "mmio-mux";
> + reg = <0x4 0x2>;
> #mux-control-cells = <1>;
> mux-reg-masks = <0x4 0x2>; /* HBMC select */
> };
> + };
> +
> + fss: bus@47030000 {
> + compatible = "simple-bus";
> + reg = <0x0 0x47030000 0x0 0x100>;
> + #address-cells = <2>;
> + #size-cells = <2>;
> + ranges;
>
> hbmc: hyperbus@47034000 {
> compatible = "ti,am654-hbmc";

I hope all the things you had to do here show you what I mean in my
comments on [0] :)

I've posted a first step patch that allows "reg-mux" node to work with
regular reg properties[1]. Which means this patch could have been just this:

--- a/arch/arm64/boot/dts/ti/k3-j7200-mcu-wakeup.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-j7200-mcu-wakeup.dtsi
@@ -305,15 +305,16 @@ wkup_i2c0: i2c@42120000 {
status = "disabled";
};

- fss: syscon@47000000 {
- compatible = "syscon", "simple-mfd";
+ fss: bus@47000000 {
+ compatible = "simple-bus";
reg = <0x00 0x47000000 0x00 0x100>;
#address-cells = <2>;
#size-cells = <2>;
ranges;

hbmc_mux: hbmc-mux {
- compatible = "mmio-mux";
+ compatible = "reg-mux";
+ reg = <0x00 0x47000004 0x00 0x2>;
#mux-control-cells = <1>;
mux-reg-masks = <0x4 0x2>; /* HBMC select */
};

Andrew

[0] https://lore.kernel.org/all/76da0b98-3274-b047-db11-ecabc117ae11@ti.com/
[1] https://lore.kernel.org/all/20230424184810.29453-1-afd@ti.com/