On Wed, Sep 30, 2026 at 11:15:48PM +0800, Jisheng Zhang wrote: > On Tue, Sep 29, 2026 at 08:44:13PM +0100, Conor Dooley wrote: > > On Tue, Sep 29, 2026 at 02:14:05PM +0800, Jisheng Zhang wrote: > > > Add device tree bindings for the resets on Synaptics SL261X SoCs. > > > > > > Signed-off-by: Jisheng Zhang > > > --- > > > .../bindings/reset/syna,sl261x-reset.yaml | 40 ++++++++++ > > > include/dt-bindings/reset/syna,sl261x-reset.h | 80 +++++++++++++++++++ > > > 2 files changed, 120 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/reset/syna,sl261x-reset.yaml > > > create mode 100644 include/dt-bindings/reset/syna,sl261x-reset.h > > > > > > diff --git a/Documentation/devicetree/bindings/reset/syna,sl261x-reset.yaml b/Documentation/devicetree/bindings/reset/syna,sl261x-reset.yaml > > > new file mode 100644 > > > index 000000000000..8cfec17df800 > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/reset/syna,sl261x-reset.yaml > > > @@ -0,0 +1,40 @@ > > > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > > > +# Copyright (C) 2026 Synaptics Incorporated > > > +%YAML 1.2 > > > +--- > > > +$id: http://devicetree.org/schemas/reset/syna,sl261x-reset.yaml# > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > + > > > +title: Synaptics SL261X reset controller > > > + > > > +maintainers: > > > + - Jisheng Zhang > > > + > > > +description: The reset controller node must be a sub-node of the chip > > > + controller node on SL261X SoCs. > > > + > > > +properties: > > > + compatible: > > > + enum: > > > + - syna,sl261x-soc-reset > > > + - syna,sl261x-system-reset > > > + > > > + "#reset-cells": > > > + const: 1 > > > + > > > +required: > > > + - compatible > > > + - "#reset-cells" > > > + > > > +additionalProperties: false > > > + > > > +examples: > > > + - | > > > + chip: chip-control@f7e10000 { > > > + reg = <0xf7e10000 0x1000>; > > > + > > > + chip_rst: reset { > > > + compatible = "syna,sl261x-soc-reset"; > > > + #reset-cells = <1>; > > > + }; > > > > Why can't this just be part of the parent node? > > Good question! IMHO, the reasons are: > > 1. the so called Gbls(Gbl means global) such as mcuGbl and > chip control Gbl contain not only reset, pinctrl and clk/plls > but also some other registers for different purposes, e.g in the > chip control gbl, there are some registers to control eth phy sel(RMII > or RGMII), and TXC 90 degree selection etc. These registers will > be used by the Ethernet driver; > > While there's no pinctrl regs in avioGbl and vppGbl. In the vppgbl, > there are some registers for DPHYTX etc. > > As can been, in different Gbls, there maybe different purposes registers, no > obvious patterns. > > So the question here is why not split the gbl into different register > spaces, and abstract each space for each function group? No, you misunderstood. I'm not asking for the register space to be split, I am asking why you cannot do | syscon@f7e1000 { | compatible = "syna,sl2610-soc-syscon", "syscon"; | reg = <0xf7e10000 0x1000>; | #clock-cells = <1>; | #reset-cells = <1>; | }; With this kind of thing, you can either use the auxiliary bus or MFD_CELL_NAME() to create the other devices. The latter is good if you've got a region with clocks that also has resets thrown in, the former is probably better if you have a syscon with a genuine assortment of different functions that you're going to be looking up via phandle. > Two blocking > points make this impossible and ugly: different reg space may not be > aligned at 4KB boundary, e.g reset: 0x350 ~ 0x37c; eth phy sel:0xa18; > some registers which belong to similar functionality, e.g clks, may not be > adjacent. This sort of thing, with non-adjacent clocks is still possible, you have a regmap just like before. > So the best way is to abstract these GBLs via. "syscon", "simple-mfd", and > put necessary subnodes such as reset, pinctrl and clks under the GBL > node. If the registers in GBL is misc control, pass the syscon phandle > to the main driver, e.g I planed to pass the syscon phandle to GMAC > driver to control the RMII/RGMII selection. And you can get the regmap from other drivers by doing phandle or compatible based lookups just like before. > > 2.follow current bg2 and bg2q style > e.g arch/arm/boot/dts/synaptics/berlin2q.dtsi > > IMHO, why bg2 and bg2q dtsi files are implemented as current > style is due to the above point 1. Unfortunately, this is the berlin2q devicetree showing its age, we've been pushing people away from nodes that exist just to probe a driver and don't provide any additional value. Something like | chip-control@f7e10000 { | reg = <0xf7e10000 0x1000>; | | chip_rst: reset { | compatible = "syna,sl261x-soc-reset"; | #reset-cells = <1>; | }; | | chip_clk: clock { | compatible = "syna,sl261x-soc-clock"; | #clock-cells = <1>; | }; is exactly the pattern we are trying to avoid. Cheers, Conor. > > Kindly let me know if there's a better solution. > > > From a quick check of the dts, the node with this subnode didn't also > > have a system-reset node too, so there's no conflict or anything of that > > nature. > > > > > + }; > > > diff --git a/include/dt-bindings/reset/syna,sl261x-reset.h b/include/dt-bindings/reset/syna,sl261x-reset.h > > > new file mode 100644 > > > index 000000000000..7034f58aae5b > > > --- /dev/null > > > +++ b/include/dt-bindings/reset/syna,sl261x-reset.h > > > @@ -0,0 +1,80 @@ > > > +/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */ > > > +/* > > > + * Copyright (C) 2026 Synaptics Incorporated > > > + * > > > + * Author: Jisheng Zhang > > > + */ > > > + > > > +#ifndef _DT_BINDINGS_SL261X_RESET_H > > > +#define _DT_BINDINGS_SL261X_RESET_H > > > + > > > +/* ACPU subsystem */ > > > +#define RST_SOC_SDIO0 0 > > > +#define RST_SOC_USB0 1 > > > +#define RST_SOC_EMMC 2 > > > +#define RST_SOC_GETH0 3 > > > +#define RST_SOC_SDIO1 4 > > > +#define RST_SOC_USB1 5 > > > +#define RST_SOC_GETH1 6 > > > +#define RST_SOC_USB0PHY 7 > > > +#define RST_SOC_USB0CORE 8 > > > +#define RST_SOC_USB0MAHB 9 > > > +#define RST_SOC_USB1PHY 10 > > > +#define RST_SOC_USB1CORE 11 > > > +#define RST_SOC_USB1MAHB 12 > > > +#define RST_SOC_UART0 13 > > > +#define RST_SOC_UART1 14 > > > +#define RST_SOC_UART2 15 > > > +#define RST_SOC_UART3 16 > > > +#define RST_SOC_I2C0 17 > > > +#define RST_SOC_I2C1 18 > > > +#define RST_SOC_SPI0 19 > > > +#define RST_SOC_SPI1 20 > > > +#define RST_SOC_SPI2 21 > > > +#define RST_SOC_SPI3 22 > > > +#define RST_SOC_APBTIMERS 23 > > > +#define RST_SOC_APBSYSCNT 24 > > > +#define RST_SOC_APBWDT 25 > > > +#define RST_SOC_APBGPIO 26 > > > +#define RST_SOC_APBDMA 27 > > > +#define RST_SOC_GPUCORE 28 > > > +#define RST_SOC_NPUCORE 29 > > > +#define RST_SOC_AVIOAIOG 30 > > > +#define RST_SOC_AVIOVPPG 31 > > > +#define RST_SOC_AVIOVIPG 32 > > > + > > > +/* system subsystem */ > > > +#define RST_SM_ADCCORE 0 > > > +#define RST_SM_ADCPRST 1 > > > +#define RST_SM_CAN0PRST 2 > > > +#define RST_SM_CAN0SRST 3 > > > +#define RST_SM_CAN1PRST 4 > > > +#define RST_SM_CAN1SRST 5 > > > +#define RST_SM_GPIOPRST 6 > > > +#define RST_SM_GPIOSRST 7 > > > +#define RST_SM_I2CM0PRST 8 > > > +#define RST_SM_I2CM0SRST 9 > > > +#define RST_SM_I2CM1PRST 10 > > > +#define RST_SM_I2CM1SRST 11 > > > +#define RST_SM_I3CPRST 12 > > > +#define RST_SM_I3CSRST 13 > > > +#define RST_SM_PDMPRST 14 > > > +#define RST_SM_PDMSRST 15 > > > +#define RST_SM_PVTHSRST 16 > > > +#define RST_SM_PVTPRST 17 > > > +#define RST_SM_PWMPERIRST 18 > > > +#define RST_SM_PWMPRST 19 > > > +#define RST_SM_SPIMPRST 20 > > > +#define RST_SM_SPIMSRST 21 > > > +#define RST_SM_SPISPRST 22 > > > +#define RST_SM_SPISSRST 23 > > > +#define RST_SM_UART0PRST 24 > > > +#define RST_SM_UART0SRST 25 > > > +#define RST_SM_UART1PRST 26 > > > +#define RST_SM_UART1SRST 27 > > > +#define RST_SM_UART2PRST 28 > > > +#define RST_SM_UART2SRST 29 > > > +#define RST_SM_UART3PRST 30 > > > +#define RST_SM_UART3SRST 31 > > > + > > > +#endif /* _DT_BINDINGS_SL261X_RESET_H */ > > > -- > > > 2.53.0 > > > > >