On 4/2/22 13:41, Krzysztof Kozlowski wrote: > On 01/04/2022 09:55, Heiko Stübner wrote: >> Hi Stephen, >> >> Am Freitag, 1. April 2022, 00:51:32 CEST schrieb Stephen Boyd: >>> Quoting Johan Jonker (2022-03-29 04:13:22) >>>> diff --git a/Documentation/devicetree/bindings/clock/rockchip,rk3188-cru.yaml b/Documentation/devicetree/bindings/clock/rockchip,rk3188-cru.yaml >>>> new file mode 100644 >>>> index 000000000..ddd7e46af >>>> --- /dev/null >>>> +++ b/Documentation/devicetree/bindings/clock/rockchip,rk3188-cru.yaml >>>> @@ -0,0 +1,78 @@ >>>> +# SPDX-License-Identifier: GPL-2.0 >>>> +%YAML 1.2 >>>> +--- >>>> +$id: http://devicetree.org/schemas/clock/rockchip,rk3188-cru.yaml# >>>> +$schema: http://devicetree.org/meta-schemas/core.yaml# >>>> + >>>> +title: Rockchip RK3188/RK3066 Clock and Reset Unit (CRU) >>>> + >>>> +maintainers: >>>> + - Elaine Zhang <zhangqing@xxxxxxxxxxxxxx> >>>> + - Heiko Stuebner <heiko@xxxxxxxxx> >>>> + >>>> +description: | >>>> + The RK3188/RK3066 clock controller generates and supplies clocks to various >>>> + controllers within the SoC and also implements a reset controller for SoC >>>> + peripherals. >>>> + Each clock is assigned an identifier and client nodes can use this identifier >>>> + to specify the clock which they consume. All available clocks are defined as >>>> + preprocessor macros in the dt-bindings/clock/rk3188-cru.h and >>>> + dt-bindings/clock/rk3066-cru.h headers and can be used in device tree sources. >>>> + Similar macros exist for the reset sources in these files. >>>> + There are several clocks that are generated outside the SoC. It is expected >>>> + that they are defined using standard clock bindings with following >>>> + clock-output-names: >>>> + - "xin24m" - crystal input - required >>>> + - "xin32k" - RTC clock - optional >>>> + - "xin27m" - 27mhz crystal input on RK3066 - optional >>>> + - "ext_hsadc" - external HSADC clock - optional >>>> + - "ext_cif0" - external camera clock - optional >>>> + - "ext_rmii" - external RMII clock - optional >>>> + - "ext_jtag" - external JTAG clock - optional >>> >>> I'd expect all these clks here to be inputs to this node. >> >> The optional clocks are all part of a circular dependency. >> >> So for example xin32k normally is generated by the pmic and fed >> back into the system, so to get xin32k, we need the pmic to probe, >> which needs i2c, which in turn already needs the clock controller. > > Are you sure that xin32k (RTC) clock should be input to the clock > controller? I would expect it is the input to the SoC RTC block, so > there is no circular dependency. clk-rk3188.c: PNAME(mux_pll_p) = { "xin24m", "xin32k" }; > > > Best regards, > Krzysztof
