Re: [RFC PATCH 4/5] arm64: dts: ti: Enable multiple MCAN for AM62x in MCU MCAN overlay

From: Nishanth Menon
Date: Fri Apr 14 2023 - 18:12:05 EST


On 22:44-20230414, Krzysztof Kozlowski wrote:
> On 14/04/2023 20:29, Nishanth Menon wrote:
> >>> +
> >>> +&cbass_mcu {
> >>> + mcu_mcan1: can@4e00000 {
> >>> + compatible = "bosch,m_can";
> >>> + reg = <0x00 0x4e00000 0x00 0x8000>,
> >>> + <0x00 0x4e08000 0x00 0x200>;
> >>> + reg-names = "message_ram", "m_can";
> >>> + power-domains = <&k3_pds 188 TI_SCI_PD_EXCLUSIVE>;
> >>> + clocks = <&k3_clks 188 6>, <&k3_clks 188 1>;
> >>> + clock-names = "hclk", "cclk";
> >>> + bosch,mram-cfg = <0x0 128 64 64 64 64 32 32>;
> >>> + pinctrl-names = "default";
> >>> + pinctrl-0 = <&mcu_mcan1_pins_default>;
> >>> + phys = <&transceiver2>;
> >>> + status = "okay";
> >>
> >> okay is by default. Why do you need it?
> >
> > mcan is not functional without pinmux, so it has been disabled by
> > default in SoC. this overlay is supposed to enable it. But this is done
> > entirely wrongly.
>
> Ah, so this is override of existing node? Why not overriding by
> label/phandle?

Yep, that is how it should be done (as every other node is done for
mcan):
a) SoC.dtsi -> introduce mcu_mcan1, disabled since no transciever or
pinmux, set status = "disabled";
b) overlay -> use the label and provide the missing properties, set
status = "okay";

The series definitely needs a respin.

--
Regards,
Nishanth Menon
Key (0xDDB5849D1736249D) / Fingerprint: F8A2 8693 54EB 8232 17A3 1A34 DDB5 849D 1736 249D