Re: [PATCH v5 2/4] dt-bindings: add bindings for rk3399 clock controller

[Heiko Stuebner <heiko@sntech.de>]

Hi Xing,

Am Montag, 28. März 2016, 01:52:12 schrieb Heiko Stübner:
> Am Samstag, 26. März 2016, 14:37:54 schrieb Xing Zheng:
> > Add devicetree bindings for Rockchip cru which found on
> > Rockchip SoCs.
> > 
> > Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
> > Signed-off-by: Jianqun Xu <jay.xu@rock-chips.com>
> > Acked-by: Rob Herring <robh@kernel.org>
> > ---
> > 
> > Changes in v5: None
> > Changes in v3: None
> > Changes in v2: None
> > 
> >  .../bindings/clock/rockchip,rk3399-cru.txt         |   83
> > 
> > ++++++++++++++++++++ 1 file changed, 83 insertions(+)
> > 
> >  create mode 100644
> > 
> > Documentation/devicetree/bindings/clock/rockchip,rk3399-cru.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/clock/rockchip,rk3399-
> 
> cru.txt
> 
> > b/Documentation/devicetree/bindings/clock/rockchip,rk3399-cru.txt new
> > file mode 100644
> > index 0000000..9427caa
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/clock/rockchip,rk3399-cru.txt
> > @@ -0,0 +1,83 @@
> > +* Rockchip RK3399 Clock and Reset Unit
> > +
> > +The RK3399 clock controller generates and supplies clock to various
> > +controllers within the SoC and also implements a reset controller for
> > SoC +peripherals.
> > +
> > +Required Properties:
> > +
> > +- compatible: PMU for CRU should be "rockchip,rk3399-pmucru"
> > +- compatible: CRU should be "rockchip,rk3399-cru"
> > +- reg: physical base address of the controller and length of memory
> 
> mapped
> 
> > +  region.
> > +- #clock-cells: should be 1.
> > +- #reset-cells: should be 1.
> > +
> > +Optional Properties:
> > +
> > +- rockchip,grf: phandle to the syscon managing the "general register
> 
> files"
> 
> > +  If missing, pll rates are not changeable, due to the missing pll lock
> > status. +
> 
> the rk3399 doesn't need the GRF, so we should drop this block for now

actually, I just saw that the GRF is needed for the static settings during 
init. So the rockchip,grf should stay but also move up to required 
properties?

Same for the grf-comment in the examples-section.


Heiko


> 
> > +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/rk3399-cru.h
> > headers and can be +used in device tree sources. Similar macros exist
> > for
> > the reset sources in +these files.
> > +
> > +External clocks:
> > +
> > +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,
> > + - "ext_i2s" - external I2S clock - optional,
> > + - "ext_gmac" - external GMAC clock - optional
> > + - "ext_hsadc" - external HSADC clock - optional,
> > + - "ext_isp" - external ISP clock - optional,
> > + - "ext_jtag" - external JTAG clock - optional
> > + - "ext_vip" - external VIP clock - optional,
> > + - "usbotg_out" - output clock of the pll in the otg phy
> 
> external clock listing needs adjusting, something like
> 
> - clkin_i2s
> - clkin_gmac
> --> remove ext_hsadc
> - clkin_cif
> --> remove ext_jtag
> --> remove ext_vip
> - clk_usbphy0_480m
> - clk_usbphy0_480m
> 
> maybe?
> 
> > +
> > +Example: General Register Files
> > +
> > +	pmugrf: syscon@ff320000 {
> > +		compatible = "rockchip,rk3399-pmugrf", "syscon";
> > +		reg = <0x0 0xff320000 0x0 0x1000>;
> > +	};
> > +
> > +	grf: syscon@ff770000 {
> > +		compatible = "rockchip,rk3399-grf", "syscon";
> > +		reg = <0x0 0xff770000 0x0 0x10000>;
> > +	};
> > +
> > +Example: Clock controller node:
> > +
> > +	pmucru: pmu-clock-controller@ff750000 {
> > +		compatible = "rockchip,rk3399-pmucru";
> > +		reg = <0x0 0xff750000 0x0 0x1000>;
> > +		rockchip,grf = <&pmugrf>;
> > +		#clock-cells = <1>;
> > +		#reset-cells = <1>;
> > +	};
> > +
> > +	cru: clock-controller@ff760000 {
> > +		compatible = "rockchip,rk3399-cru";
> > +		reg = <0x0 0xff760000 0x0 0x1000>;
> > +		rockchip,grf = <&grf>;
> > +		#clock-cells = <1>;
> > +		#reset-cells = <1>;
> > +	};
> 
> also here drop grf nodes and rockchip,grf properties?
> 
> > +
> > +Example: UART controller node that consumes the clock generated by the
> > clock +  controller:
> > +
> > +	uart0: serial@ff1a0000 {
> > +		compatible = "rockchip,rk3399-uart", "snps,dw-apb-uart";
> > +		reg = <0x0 0xff180000 0x0 0x100>;
> > +		clocks = <&cru SCLK_UART0>, <&cru PCLK_UART0>;
> > +		clock-names = "baudclk", "apb_pclk";
> > +		interrupts = <GIC_SPI 99 IRQ_TYPE_LEVEL_HIGH>;
> > +		reg-shift = <2>;
> > +		reg-io-width = <4>;
> > +	};