Re: [PATCH 4/7] arm64: dts: rockchip: Add pinctrl and gpio nodes for RK3528

[Yao Zi <ziyao@disroot.org>]

On Sun, Mar 02, 2025 at 12:52:18PM +0100, Heiko Stübner wrote:
> Am Sonntag, 2. März 2025, 12:14:48 MEZ schrieb Jonas Karlman:
> > Hi Yao Zi,
> > 
> > On 2025-02-28 11:46, Yao Zi wrote:
> > > On Fri, Feb 28, 2025 at 06:40:10AM +0000, Jonas Karlman wrote:
> > >> Add pinctrl and gpio nodes for RK3528 and import rk3528-pinctrl.dtsi
> > >> from vendor linux-6.1-stan-rkr5 kernel with the hdmi-pins-idle node
> > >> removed due to missing label reference to pcfg_output_low_pull_down.
> > >>
> > >> Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
> > >> ---
> > >> This was mostly imported from vendor kernel, however the main commit [1]
> > >> list 28 signed-off-by tags, unclear who I should use as author and what
> > >> signed-off-by tags to include.
> > >>
> > >> [1] https://github.com/rockchip-linux/kernel/commit/c17d6325959f0ec1af901e8a17919163454190a2
> > >> ---
> > >>  .../boot/dts/rockchip/rk3528-pinctrl.dtsi     | 1397 +++++++++++++++++
> > >>  arch/arm64/boot/dts/rockchip/rk3528.dtsi      |   82 +
> > >>  2 files changed, 1479 insertions(+)
> > >>  create mode 100644 arch/arm64/boot/dts/rockchip/rk3528-pinctrl.dtsi
> > >>
> > > 
> > >> diff --git a/arch/arm64/boot/dts/rockchip/rk3528.dtsi b/arch/arm64/boot/dts/rockchip/rk3528.dtsi
> > >> index 0fb90f5c291c..d3e2a64ff2d5 100644
> > >> --- a/arch/arm64/boot/dts/rockchip/rk3528.dtsi
> > >> +++ b/arch/arm64/boot/dts/rockchip/rk3528.dtsi
> > >> @@ -4,8 +4,10 @@
> > >>   * Copyright (c) 2024 Yao Zi <ziyao@disroot.org>
> > >>   */
> > >>  
> > >> +#include <dt-bindings/gpio/gpio.h>
> > >>  #include <dt-bindings/interrupt-controller/arm-gic.h>
> > >>  #include <dt-bindings/interrupt-controller/irq.h>
> > >> +#include <dt-bindings/pinctrl/rockchip.h>
> > >>  #include <dt-bindings/clock/rockchip,rk3528-cru.h>
> > >>  #include <dt-bindings/reset/rockchip,rk3528-cru.h>
> > >>  
> > >> @@ -17,6 +19,11 @@ / {
> > >>  	#size-cells = <2>;
> > >>  
> > >>  	aliases {
> > >> +		gpio0 = &gpio0;
> > >> +		gpio1 = &gpio1;
> > >> +		gpio2 = &gpio2;
> > >> +		gpio3 = &gpio3;
> > >> +		gpio4 = &gpio4;
> > >>  		serial0 = &uart0;
> > >>  		serial1 = &uart1;
> > >>  		serial2 = &uart2;
> > >> @@ -166,6 +173,11 @@ cru: clock-controller@ff4a0000 {
> > >>  			#reset-cells = <1>;
> > >>  		};
> > >>  
> > >> +		ioc_grf: syscon@ff540000 {
> > >> +			compatible = "rockchip,rk3528-ioc-grf", "syscon";
> > >> +			reg = <0x0 0xff540000 0x0 0x40000>;
> > >> +		};
> > >> +
> > >>  		uart0: serial@ff9f0000 {
> > >>  			compatible = "rockchip,rk3528-uart", "snps,dw-apb-uart";
> > >>  			reg = <0x0 0xff9f0000 0x0 0x100>;
> > >> @@ -264,5 +276,75 @@ saradc: adc@ffae0000 {
> > >>  			#io-channel-cells = <1>;
> > >>  			status = "disabled";
> > >>  		};
> > >> +
> > >> +		pinctrl: pinctrl {
> > >> +			compatible = "rockchip,rk3528-pinctrl";
> > >> +			rockchip,grf = <&ioc_grf>;
> > >> +			#address-cells = <2>;
> > >> +			#size-cells = <2>;
> > >> +			ranges;
> > > 
> > > I doubt whether the pincontroller should be placed under simple-bus:
> > > without a reg property, it doesn't look like a MMIO device.
> > > 
> > > Actually it is, although all the registers stay in the ioc grf. Maybe
> > > it should be considered as child of the grf.
> > 
> > This follows how pinctrl was added for RK3576 and what is proposed for
> > RK3562 [2]. I have too little knowledge to know if this needs to change
> > or if this should follow similar SoCs.
> > 
> > [2] https://lore.kernel.org/r/20250227111913.2344207-15-kever.yang@rock-chips.com
> 
> The reg address shouldn't matter here I think.
> 
> The "soc"-bus describes the elements contained in the soc (surrounding the
> cpu cores) and the pinctrl controller definitly is part of the soc itself.
> 
> So when looking at the scope, it does belong there and also the
>  gpio-controller elements do have mmio addresses :-)

Thanks for the explanation, it makes sense to me.

> Heiko
> 

Best regards,
Yao Zi