Re: [PATCH 14/16] arm64: dts: axis: Add initial device tree support

[sungmin park <smn1196@coasia.com>]

2025-07-10 (목), 09:02 +0200, Krzysztof Kozlowski:
> On 10/07/2025 02:20, ksk4725@coasia.com wrote:
> > From: sungminpark <smn1196@coasia.com>
> > 
> > Add initial device tree support for Axis ARTPEC-8 SoC and Grizzly
> > board.
> > This SoC contains four cores of cortex-a53 CPUs and other various
> 
> Subject: Initial device tree of what?

Ok, I will update the patch title in next version.

> 
> > peripheral IPs.
> > 
> > Signed-off-by: Ravi Patel <ravi.patel@samsung.com>
> > Signed-off-by: sungminpark <smn1196@coasia.com>
> > ---
> >  MAINTAINERS                                  |  14 ++
> >  arch/arm64/Kconfig.platforms                 |  13 +
> >  arch/arm64/boot/dts/Makefile                 |   1 +
> >  arch/arm64/boot/dts/axis/Makefile            |   4 +
> >  arch/arm64/boot/dts/axis/artpec8-grizzly.dts |  67 +++++
> >  arch/arm64/boot/dts/axis/artpec8.dtsi        | 252
> > +++++++++++++++++++
> >  6 files changed, 351 insertions(+)
> >  create mode 100644 arch/arm64/boot/dts/axis/Makefile
> >  create mode 100644 arch/arm64/boot/dts/axis/artpec8-grizzly.dts
> >  create mode 100644 arch/arm64/boot/dts/axis/artpec8.dtsi
> > 
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index fa1e04e87d1d..371005f3f41a 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -2320,6 +2320,20 @@ F:       drivers/crypto/axis
> >  F:     drivers/mmc/host/usdhi6rol0.c
> >  F:     drivers/pinctrl/pinctrl-artpec*
> >  
> > +ARM/ARTPEC ARM64 MACHINE SUPPORT
> 
> This is samsung soc, so I need a pattern for that as well as I will
> be
> handling patches.

Can you please explain what you mean to say?

> 
> > +M:     Jesper Nilsson <jesper.nilsson@axis.com>
> > +M:     Ravi Patel <ravi.patel@samsung.com>
> > +M:     SeonGu Kang <ksk4725@coasia.com>
> > +M:     SungMin Park <smn1196@coasia.com>
> 
> Please keep only maintainers who will actually perform reviews of the
> code. I am not even sure if this is worth separate entry outside of
> Samsung. Please list the IP blocks which are not Samsung here.

Is it fine if I merge the list with existing ARTPEC entry?
Samsung and Coasia entry can be removed from list as Axis will be only
maintaining the ARTPEC-8 SoC in future.
Please suggest your opinion here.

> 
> > +L:     linux-arm-kernel@lists.infradead.org (moderated for non-
> > subscribers)
> > +L:     linux-samsung-soc@vger.kernel.org
> > +L:     linux-arm-kernel@axis.com
> > +S:     Maintained
> > +F:     Documentation/devicetree/bindings/clock/axis,artpec*-
> > clock.yaml
> > +F:     arch/arm64/boot/dts/axis/
> > +F:     drivers/clk/samsung/clk-artpec*.c
> > +F:     include/dt-bindings/clock/axis,artpec*-clk.h
> > +
> >  ARM/ASPEED I2C DRIVER
> >  M:     Ryan Chen <ryan_chen@aspeedtech.com>
> >  R:     Benjamin Herrenschmidt <benh@kernel.crashing.org>
> > diff --git a/arch/arm64/Kconfig.platforms
> > b/arch/arm64/Kconfig.platforms
> > index 8b76821f190f..418ee47227c1 100644
> > --- a/arch/arm64/Kconfig.platforms
> > +++ b/arch/arm64/Kconfig.platforms
> > @@ -40,6 +40,19 @@ config ARCH_APPLE
> >           This enables support for Apple's in-house ARM SoC family,
> > such
> >           as the Apple M1.
> >  
> > +config ARCH_ARTPEC
> > +       bool "Axis Communications ARTPEC SoC Family"
> > +       help
> > +          This enables support for the ARMv8 based ARTPEC SoC
> > Family.
> > +
> > +config ARCH_ARTPEC8
> 
> No, drop. One ARCH symbol.
> 
> > +       bool "Axis ARTPEC-8 SoC Platform"
> > +       depends on ARCH_ARTPEC
> > +       depends on ARCH_EXYNOS
> 
> And that's the proof that this is Samsung SoC.

Should I move the axis folder inside exynos just like google did? In
that case we don't need separate ARCH entry anymore.
Or should I follow the tesla FSD style to add axis folder outside
exynos? In that case I will keep ARCH_ARTPEC entry only.
Please suggest your opinion here.

> 
> > +       select ARM_GIC
> > +       help
> > +         This enables support for the Axis ARTPEC-8 SoC.
> > +
> >  menuconfig ARCH_BCM
> >         bool "Broadcom SoC Support"
> >  
> > diff --git a/arch/arm64/boot/dts/Makefile
> > b/arch/arm64/boot/dts/Makefile
> > index 79b73a21ddc2..6b6a3aedc2ed 100644
> > --- a/arch/arm64/boot/dts/Makefile
> > +++ b/arch/arm64/boot/dts/Makefile
> > @@ -9,6 +9,7 @@ subdir-y += amlogic
> >  subdir-y += apm
> >  subdir-y += apple
> >  subdir-y += arm
> > +subdir-y += axis
> >  subdir-y += bitmain
> >  subdir-y += blaize
> >  subdir-y += broadcom
> > diff --git a/arch/arm64/boot/dts/axis/Makefile
> > b/arch/arm64/boot/dts/axis/Makefile
> > new file mode 100644
> > index 000000000000..ccf00de64016
> > --- /dev/null
> > +++ b/arch/arm64/boot/dts/axis/Makefile
> > @@ -0,0 +1,4 @@
> > +# SPDX-License-Identifier: GPL-2.0
> > +
> > +dtb-$(CONFIG_ARCH_ARTPEC) += \
> > +       artpec8-grizzly.dtb
> > diff --git a/arch/arm64/boot/dts/axis/artpec8-grizzly.dts
> > b/arch/arm64/boot/dts/axis/artpec8-grizzly.dts
> > new file mode 100644
> > index 000000000000..7671130a0333
> > --- /dev/null
> > +++ b/arch/arm64/boot/dts/axis/artpec8-grizzly.dts
> > @@ -0,0 +1,67 @@
> > +// SPDX-License-Identifier: (GPL-2.0 OR MIT)
> > +/*
> > + * Axis ARTPEC-8 Grizzly board device tree source
> > + *
> > + * Copyright (c) 2022-2025 Samsung Electronics Co., Ltd.
> > + *             https://www.samsung.com
> > + * Copyright (c) 2022-2025  Axis Communications AB.
> > + *             https://www.axis.com
> > + */
> > +
> > +/dts-v1/;
> > +#include "artpec8.dtsi"
> > +#include <dt-bindings/gpio/gpio.h>
> > +/ {
> > +       model = "ARTPEC-8 grizzly board";
> > +       compatible = "axis,artpec8-grizzly", "axis,artpec8";
> > +
> > +       aliases {
> > +               serial0 = &serial_0;
> > +       };
> > +
> > +       chosen {
> > +               stdout-path = &serial_0;
> > +       };
> > +
> > +       memory@80000000 {
> > +               device_type = "memory";
> > +               reg = <0x0 0x80000000 0x0 0x80000000>;
> > +       };
> > +};
> > +
> > +&osc_clk {
> > +       clock-frequency = <50000000>;
> > +       status = "okay";
> 
> Why?

Ok, I will remove status property.

> 
> > +};
> > +
> > +&serial_0 {
> 
> Follow DTS coding style. s > c
> o > c

Ok, I will reorder the nodes in alphabetical order.

> 
> 
> > +       status = "okay";
> > +};
> > +
> > +&cmu_cmu {
> > +       status = "okay";
> > +};
> > +
> > +&cmu_bus {
> > +       status = "okay";
> > +};
> > +
> > +&cmu_core {
> > +       status = "okay";
> > +};
> > +
> > +&cmu_cpucl {
> > +       status = "okay";
> > +};
> > +
> > +&cmu_fsys {
> > +       status = "okay";
> > +};
> > +
> > +&cmu_imem {
> > +       status = "okay";
> > +};
> > +
> > +&cmu_peri {
> > +       status = "okay";
> > +};
> > diff --git a/arch/arm64/boot/dts/axis/artpec8.dtsi
> > b/arch/arm64/boot/dts/axis/artpec8.dtsi
> > new file mode 100644
> > index 000000000000..296192560adf
> > --- /dev/null
> > +++ b/arch/arm64/boot/dts/axis/artpec8.dtsi
> > @@ -0,0 +1,252 @@
> > +// SPDX-License-Identifier: (GPL-2.0 OR MIT)
> > +/*
> > + * Axis ARTPEC-8 SoC device tree source
> > + *
> > + * Copyright (c) 2022-2025 Samsung Electronics Co., Ltd.
> > + *             https://www.samsung.com
> > + * Copyright (c) 2022-2025  Axis Communications AB.
> > + *             https://www.axis.com
> > + */
> > +
> > +#include <dt-bindings/interrupt-controller/arm-gic.h>
> > +#include <dt-bindings/clock/axis,artpec8-clk.h>
> > +
> > +/ {
> > +       compatible = "axis,artpec8";
> > +       interrupt-parent = <&gic>;
> > +       #address-cells = <2>;
> > +       #size-cells = <2>;
> > +
> > +       cpus {
> > +               #address-cells = <1>;
> > +               #size-cells = <0>;
> > +
> > +               cpu0: cpu@0 {
> > +                       device_type = "cpu";
> > +                       compatible = "arm,cortex-a53";
> > +                       reg = <0x0>;
> > +                       cpu-idle-states = <&cpu_sleep>;
> > +                       enable-method = "psci";
> > +                       clocks = <&cmu_cpucl DOUT_CLK_CPUCL_CPU>;
> > +                       clock-names = "dout_clk_cpucl_cpu";
> > +                       clock-frequency = <1200000000>;
> 
> This feels wrong. Frequency changes, doesn't it?

Ok, I will remove the “clock-frequency” property in the next version.

> 
> > +               };
> > +
> > +               cpu1: cpu@1 {
> > +                       device_type = "cpu";
> > +                       compatible = "arm,cortex-a53";
> > +                       reg = <0x1>;
> > +                       cpu-idle-states = <&cpu_sleep>;
> > +                       enable-method = "psci";
> > +                       clock-frequency = <1200000000>;
> > +               };
> > +
> > +               cpu2: cpu@2 {
> > +                       device_type = "cpu";
> > +                       compatible = "arm,cortex-a53";
> > +                       reg = <0x2>;
> > +                       cpu-idle-states = <&cpu_sleep>;
> > +                       enable-method = "psci";
> > +                       clock-frequency = <1200000000>;
> > +               };
> > +
> > +               cpu3: cpu@3 {
> > +                       device_type = "cpu";
> > +                       compatible = "arm,cortex-a53";
> > +                       reg = <0x3>;
> > +                       cpu-idle-states = <&cpu_sleep>;
> > +                       enable-method = "psci";
> > +                       clock-frequency = <1200000000>;
> > +               };
> > +
> > +               idle-states {
> > +                       entry-method = "psci";
> > +
> > +                       cpu_sleep: cpu-sleep {
> > +                               compatible = "arm,idle-state";
> > +                               arm,psci-suspend-param =
> > <0x0010000>;
> > +                               local-timer-stop;
> > +                               entry-latency-us = <300>;
> > +                               exit-latency-us = <1200>;
> > +                               min-residency-us = <2000>;
> > +                       };
> > +               };
> > +       };
> > +
> > +       timer {
> 
> Also wrongly ordered. See DTS coding style.

Ok, I will reorder the nodes in alphabetical order.

> 
> 
> > +               compatible = "arm,armv8-timer";
> > +               interrupts = <GIC_PPI 13 IRQ_TYPE_LEVEL_LOW>,
> > +                            <GIC_PPI 14 IRQ_TYPE_LEVEL_LOW>,
> > +                            <GIC_PPI 11 IRQ_TYPE_LEVEL_LOW>,
> > +                            <GIC_PPI 10 IRQ_TYPE_LEVEL_LOW>;
> > +       };
> > +
> > +       pmu {
> > +               compatible = "arm,cortex-a53-pmu";
> > +               interrupts = <GIC_SPI 10 IRQ_TYPE_LEVEL_HIGH>,
> > +                            <GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>,
> > +                            <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
> > +                            <GIC_SPI 13 IRQ_TYPE_LEVEL_HIGH>;
> > +               interrupt-affinity = <&cpu0>, <&cpu1>, <&cpu2>,
> > <&cpu3>;
> > +       };
> > +
> > +       psci {
> > +               compatible = "arm,psci-0.2";
> > +               method = "smc";
> > +       };
> > +
> > +       osc_clk: xxti {
> 
> clock-xxti

Ok, I will rename node name to clock-xxti.

> 
> > +               compatible = "fixed-clock";
> > +               clock-output-names = "xxti";
> > +               #clock-cells = <0>;
> > +       };
> > +
> > +       fin_pll: fin_pll {
> 
> DTS coding style.

Ok, I will rename the label to clock_finpll.

> 
> > +               compatible = "fixed-factor-clock";
> > +               clocks = <&osc_clk>;
> > +               #clock-cells = <0>;
> > +               clock-div = <2>;
> > +               clock-mult = <1>;
> > +               clock-output-names = "fin_pll";
> > +       };
> > +
> > +       soc: soc@0 {
> > +               compatible = "simple-bus";
> > +               #address-cells = <1>;
> > +               #size-cells = <1>;
> > +               ranges = <0x0 0x0 0x0 0x17000000>;
> 
> DTS coding style.

Ok, I will move the ranges property next to compatible.

> 
> > +
> > +               mct@10040000 {
> 
> Look at other SoCs first
> 
> > +                       compatible = "samsung,exynos4210-mct";
> 
> You just missed two years of development, right? Look at other SoCs.

Ok, I will add “axis,artpec8-mct” in the compatible string and rename
the node name to "timer".

> 
> 
> > +                       reg = <0x10040000 0x1000>;
> > +                       clocks = <&fin_pll>, <&cmu_imem
> > MOUT_IMEM_ACLK_USER>;
> > +                       clock-names = "fin_pll", "mct";
> > +                       interrupts = <GIC_SPI 455
> > IRQ_TYPE_LEVEL_HIGH>,
> > +                                    <GIC_SPI 456
> > IRQ_TYPE_LEVEL_HIGH>,
> > +                                    <GIC_SPI 457
> > IRQ_TYPE_LEVEL_HIGH>,
> > +                                    <GIC_SPI 458
> > IRQ_TYPE_LEVEL_HIGH>,
> > +                                    <GIC_SPI 459
> > IRQ_TYPE_LEVEL_HIGH>,
> > +                                    <GIC_SPI 460
> > IRQ_TYPE_LEVEL_HIGH>,
> > +                                    <GIC_SPI 461
> > IRQ_TYPE_LEVEL_HIGH>,
> > +                                    <GIC_SPI 462
> > IRQ_TYPE_LEVEL_HIGH>,
> > +                                    <GIC_SPI 463
> > IRQ_TYPE_LEVEL_HIGH>,
> > +                                    <GIC_SPI 464
> > IRQ_TYPE_LEVEL_HIGH>,
> > +                                    <GIC_SPI 465
> > IRQ_TYPE_LEVEL_HIGH>,
> > +                                    <GIC_SPI 466
> > IRQ_TYPE_LEVEL_HIGH>;
> > +               };
> > +
> > +               gic: interrupt-controller@10201000 {
> > +                       compatible = "arm,gic-400";
> > +                       #interrupt-cells = <3>;
> > +                       #address-cells = <0>;
> > +                       interrupt-controller;
> > +                       reg = <0x10201000 0x00001000>,
> > +                             <0x10202000 0x00002000>,
> > +                             <0x10204000 0x00002000>,
> > +                             <0x10206000 0x00002000>;
> 
> DTS coding style.

Ok, I will move the reg property next to compatible.

> 
> > +               };
> > +
> > +               cmu_cmu: clock-controller@12400000 {
> > +                       compatible = "axis,artpec8-cmu-cmu";
> > +                       reg = <0x12400000 0x4000>;
> > +                       #clock-cells = <1>;
> > +                       clocks = <&fin_pll>;
> > +                       clock-names = "fin_pll";
> > +                       status = "disabled";
> 
> Why? No, don't do that, even if clock frequency of xxti is missing.
> Look
> at other SoCs.

Ok, I will remove status property from clock-controller nodes.
The clock frequency of xxti is added in board dts file.

> 
> 
> > +               };
> > +
> > +               cmu_bus: clock-controller@12c10000 {
> > +                       compatible = "axis,artpec8-cmu-bus";
> > +                       reg = <0x12c10000 0x4000>;
> > +                       #clock-cells = <1>;
> > +                       clocks = <&fin_pll>,
> > +                                <&cmu_cmu DOUT_CLKCMU_BUS_BUS>,
> > +                                <&cmu_cmu DOUT_CLKCMU_BUS_DLP>;
> > +                       clock-names = "fin_pll",
> > +                                     "dout_clkcmu_bus_bus",
> > +                                     "dout_clkcmu_bus_dlp";
> > +                       status = "disabled";
> > +               };
> > +
> > +               cmu_core: clock-controller@12410000 {
> > +                       compatible = "axis,artpec8-cmu-core";
> > +                       reg = <0x12410000 0x4000>;
> > +                       #clock-cells = <1>;
> > +                       clocks = <&fin_pll>,
> > +                                <&cmu_cmu DOUT_CLKCMU_CORE_MAIN>,
> > +                                <&cmu_cmu DOUT_CLKCMU_CORE_DLP>;
> > +                       clock-names = "fin_pll",
> > +                                     "dout_clkcmu_core_main",
> > +                                     "dout_clkcmu_core_dlp";
> > +                       status = "disabled";
> > +               };
> > +
> > +               cmu_cpucl: clock-controller@11410000 {
> > +                       compatible = "axis,artpec8-cmu-cpucl";
> > +                       reg = <0x11410000 0x4000>;
> > +                       #clock-cells = <1>;
> > +                       clocks = <&fin_pll>,
> > +                                <&cmu_cmu
> > DOUT_CLKCMU_CPUCL_SWITCH>;
> > +                       clock-names = "fin_pll",
> > +                               "dout_clkcmu_cpucl_switch";
> > +                       status = "disabled";
> > +               };
> > +
> > +               cmu_fsys: clock-controller@16c10000 {
> > +                       compatible = "axis,artpec8-cmu-fsys";
> > +                       reg = <0x16c10000 0x4000>;
> > +                       #clock-cells = <1>;
> > +                       clocks = <&fin_pll>,
> > +                                <&cmu_cmu DOUT_CLKCMU_FSYS_SCAN0>,
> > +                                <&cmu_cmu DOUT_CLKCMU_FSYS_SCAN1>,
> > +                                <&cmu_cmu DOUT_CLKCMU_FSYS_BUS>,
> > +                                <&cmu_cmu DOUT_CLKCMU_FSYS_IP>;
> > +                       clock-names = "fin_pll",
> > +                                     "dout_clkcmu_fsys_scan0",
> > +                                     "dout_clkcmu_fsys_scan1",
> > +                                     "dout_clkcmu_fsys_bus",
> > +                                     "dout_clkcmu_fsys_ip";
> > +                       status = "disabled";
> > +               };
> > +
> > +               cmu_imem: clock-controller@10010000 {
> 
> DTS coding style.

Ok, I will sort the cmu nodes according to their address.

Thanks,
sungminpark

> 
> 
> 
> Best regards,
> Krzysztof