Re: [PATCH v2] qcom: ipq40xx: Add basic board/dts support for IPQ40XX SoC

From: Bjorn Andersson
Date: Fri Aug 21 2015 - 12:22:02 EST


On Fri 21 Aug 03:32 PDT 2015, Varadarajan Narayanan wrote:

> Add initial dts files and SoC support for IPQ40XX
>
> Signed-off-by: Varadarajan Narayanan <varada@xxxxxxxxxxxxxx>
> ---
> Changes in v2:
> - Added devicetree bindings documentation
>
> .../devicetree/bindings/clock/qca,gcnt.txt | 14 ++++
> Documentation/devicetree/bindings/ipq.txt | 16 ++++
> arch/arm/boot/dts/Makefile | 3 +-
> arch/arm/boot/dts/qcom-ipq40xx-r3pc.dts | 33 +++++++++
> arch/arm/boot/dts/qcom-ipq40xx.dtsi | 86 ++++++++++++++++++++++
> arch/arm/configs/ipq_defconfig | 1 +
> arch/arm/mach-qcom/Kconfig | 4 +
> arch/arm/mach-qcom/board.c | 1 +
> 8 files changed, 157 insertions(+), 1 deletion(-)
> create mode 100644 Documentation/devicetree/bindings/clock/qca,gcnt.txt
> create mode 100644 Documentation/devicetree/bindings/ipq.txt
> create mode 100644 arch/arm/boot/dts/qcom-ipq40xx-r3pc.dts
> create mode 100644 arch/arm/boot/dts/qcom-ipq40xx.dtsi
>
> diff --git a/Documentation/devicetree/bindings/clock/qca,gcnt.txt b/Documentation/devicetree/bindings/clock/qca,gcnt.txt
> new file mode 100644
> index 0000000..dd0d71e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/clock/qca,gcnt.txt
> @@ -0,0 +1,14 @@
> +QCA Global Counter

I don't think I've seen the "global counter" blocks before, what is it?
What does it do? Do you have a upcoming driver for it? (Have I just
missed it?)

You add it to the dts below, but don't seem to reference it. What is
its purpose?

Also, you should split this definition into its own patch.

> +------------------------------------------------
> +
> +Required properties :
> +- compatible : "qcom,qca-gcnt"
> +
> +- reg : shall contain base register location and length
> +
> +Example:
> +
> + counter {
> + compatible = "qcom,qca-gcnt";
> + reg = <0x004a1000 0x4>;

Most of the time when there's a device consuming one register it turns
out to be part of some larger hw block and down the road things get
complicated from the fact that we mapped 4 bytes in the middle.

Is this part of a larger block? Can we better implement that as a
simple-mfd or syscon?

> + };
> diff --git a/Documentation/devicetree/bindings/ipq.txt b/Documentation/devicetree/bindings/ipq.txt
> new file mode 100644
> index 0000000..7d56bd0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/ipq.txt

This doesn't really follow the general pattern of this directory. There
are some files like this, but then you should probably name it
qualcomm.txt.

> @@ -0,0 +1,16 @@
> +Qualcomm IPQ device tree bindings
> +---------------------------------
> +
> +System on Chip
> +
> +Device tree must specify which SoC it uses, with one of the
> +following compatible strings
> +
> + "qcom,ipq40xx"
> +
> +Platform
> +
> +Device tree must specify which Platform it uses, with one of the
> +following compatible strings
> +
> + "qcom,ipq40xx-r3pc"

I would expect an "ipq.txt" to contain "qcom,ipq8064-ap148" and
"qcom,ipq8064" as well.

> diff --git a/arch/arm/boot/dts/Makefile b/arch/arm/boot/dts/Makefile
> index 246473a..6b4caee 100644
> --- a/arch/arm/boot/dts/Makefile
> +++ b/arch/arm/boot/dts/Makefile
> @@ -477,7 +477,8 @@ dtb-$(CONFIG_ARCH_QCOM) += \
> qcom-ipq8064-ap148.dtb \
> qcom-msm8660-surf.dtb \
> qcom-msm8960-cdp.dtb \
> - qcom-msm8974-sony-xperia-honami.dtb
> + qcom-msm8974-sony-xperia-honami.dtb \
> + qcom-ipq40xx-r3pc.dtb

Please insert your entry alphabetically.

> dtb-$(CONFIG_ARCH_REALVIEW) += \
> arm-realview-pb1176.dtb
> dtb-$(CONFIG_ARCH_ROCKCHIP) += \
> diff --git a/arch/arm/boot/dts/qcom-ipq40xx-r3pc.dts b/arch/arm/boot/dts/qcom-ipq40xx-r3pc.dts
> new file mode 100644
> index 0000000..7e4e629
> --- /dev/null
> +++ b/arch/arm/boot/dts/qcom-ipq40xx-r3pc.dts
> @@ -0,0 +1,33 @@
> +/* Copyright (c) 2014, The Linux Foundation. All rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include "qcom-ipq40xx.dtsi"
> +
> +/ {
> + model = "Qualcomm Technologies, Inc. IPQ40XX R3PC";
> + compatible = "qcom,ipq40xx-r3pc", "qcom,ipq40xx";
> +
> + memory {
> + device_type = "memory";
> + reg = <0x80000000 0x20000000>; /* 512MB */
> + };
> +
> + chosen {
> + bootargs = "root=/dev/ram rw init=/init console=ttyMSM0,115200n8 initrd=0x82000000,0x000E2246";
> + };
> +
> + soc {
> + serial@78b0000 {
> + status = "ok";
> + };
> + };
> +};

This part looks good.

> diff --git a/arch/arm/boot/dts/qcom-ipq40xx.dtsi b/arch/arm/boot/dts/qcom-ipq40xx.dtsi
> new file mode 100644
> index 0000000..76c55a3
> --- /dev/null
> +++ b/arch/arm/boot/dts/qcom-ipq40xx.dtsi
> @@ -0,0 +1,86 @@
> +/*
> + * Copyright (c) 2014, The Linux Foundation. All rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +/dts-v1/;
> +
> +#include "skeleton.dtsi"
> +
> +/ {
> + model = "Qualcomm Technologies, Inc. IPQ40XX";
> + compatible = "qcom,ipq40xx";
> + interrupt-parent = <&intc>;
> +
> + cpus {
> + #address-cells = <1>;
> + #size-cells = <0>;
> + cpu@0 {
> + device_type = "cpu";
> + compatible = "arm,cortex-a7";
> + reg = <0x0>;
> + };
> +
> + cpu@1 {
> + device_type = "cpu";
> + compatible = "arm,cortex-a7";
> + reg = <0x1>;
> + };
> +
> + cpu@2 {
> + device_type = "cpu";
> + compatible = "arm,cortex-a7";
> + reg = <0x2>;
> + };
> +
> + cpu@3 {
> + device_type = "cpu";
> + compatible = "arm,cortex-a7";
> + reg = <0x3>;
> + };
> + };
> +
> + soc {
> + #address-cells = <1>;
> + #size-cells = <1>;
> + ranges;
> + compatible = "simple-bus";
> +
> + intc: interrupt-controller@b000000 {
> + compatible = "qcom,msm-qgic2";
> + interrupt-controller;
> + #interrupt-cells = <3>;
> + reg = <0x0b000000 0x1000>,
> + <0x0b002000 0x1000>;
> + };
> +
> + counter {
> + compatible = "qcom,qca-gcnt";
> + reg = <0x004a1000 0x4>;
> + };
> +
> + timer {
> + compatible = "arm,armv7-timer";
> + interrupts = <1 2 0xf08>,
> + <1 3 0xf08>,
> + <1 4 0xf08>,
> + <1 1 0xf08>;
> + clock-frequency = <20833333>;
> + };
> +
> + serial@78b0000 {
> + compatible = "qcom,msm-uartdm-v1.4", "qcom,msm-uartdm";
> + reg = <0x78b0000 0x200>;
> + interrupts = <0 108 0>;
> + status = "disabled";
> + };
> + };
> +};

Unless the counter has a critical function I suggest you add that
separately, otherwise this looks good.

> diff --git a/arch/arm/configs/ipq_defconfig b/arch/arm/configs/ipq_defconfig
> index 1cabd8b..054a159 100644
> --- a/arch/arm/configs/ipq_defconfig
> +++ b/arch/arm/configs/ipq_defconfig
> @@ -22,6 +22,7 @@ CONFIG_ARCH_MSM8X60=y
> CONFIG_ARCH_MSM8960=y
> CONFIG_ARCH_MSM8974=y
> CONFIG_ARCH_IPQ8064=y
> +CONFIG_ARCH_IPQ40XX=y
> CONFIG_SMP=y
> CONFIG_PREEMPT=y
> CONFIG_AEABI=y
> diff --git a/arch/arm/mach-qcom/Kconfig b/arch/arm/mach-qcom/Kconfig
> index fab49a2..3add9f9 100644
> --- a/arch/arm/mach-qcom/Kconfig
> +++ b/arch/arm/mach-qcom/Kconfig
> @@ -26,4 +26,8 @@ config ARCH_IPQ8064
> bool "Enable support for IPQ806x"
> select CLKSRC_QCOM
>
> +config ARCH_IPQ40XX
> + bool "Enable support for IPQ40XX"
> + select HAVE_ARM_ARCH_TIMER
> +

Please insert your entry alphabetically.

> endif
> diff --git a/arch/arm/mach-qcom/board.c b/arch/arm/mach-qcom/board.c
> index 6d8bbf7..566487d 100644
> --- a/arch/arm/mach-qcom/board.c
> +++ b/arch/arm/mach-qcom/board.c
> @@ -22,6 +22,7 @@ static const char * const qcom_dt_match[] __initconst = {
> "qcom,ipq8064",
> "qcom,msm8660-surf",
> "qcom,msm8960-cdp",
> + "qcom,ipq40xx-r3pc",

Please add qcom,ipq40xx instead, so that we don't need to list every
single device.

Also, please keep the list alphabetically sorted.

> NULL
> };

Regards,
Bjorn
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/