[PATCH v2] ARM: realview: basic device tree implementation
Rob Herring
robh at kernel.org
Thu May 22 06:17:27 PDT 2014
On Thu, May 8, 2014 at 5:08 PM, Linus Walleij <linus.walleij at linaro.org> wrote:
> This implements basic device tree boot support for the RealView
> platforms, with a basic device tree for ARM PB1176 as an example.
>
> The implementation is done with a new DT-specific board file
> using only pre-existing bindings for the basic IRQ, timer and
> serial port drivers. A new compatible type is added to the GIC
> for the ARM1176.
>
> This implementation uses the MFD syscon handle from day one to
> access the system controller registers, and register the devices
> using the SoC bus.
>
> Cc: Arnd Bergmann <arnd at arndb.de>
> Cc: Rob Herring <robh at kernel.org>
> Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
> ---
> ChangeLog v1->v2:
> - Adjust timer clock names to be the same as the example in the
> device tree binding.
> - Remove all memory fixup code - this should be handled by the
> device tree specification of memory areas or by special MM hacks
> for the RealView PBX.
> - Fix the documentation around syscon to specify that it can be in
> any node, need not be the root node.
> - Switch device tree license to the BSD license, taken from
> arch/powerpc/boot/dts/p1024rdb_32b.dts
> - Add a hunk for the new compatible string to
> Documentation/devicetree/bindings/arm/gic.txt
> - Move the clocks out of the SoC node, certainly the xtal is not
> sitting on the SoC...
> - Sort the selects in Kconfig alphabetically
> - Use IS_ENABLED() for the l2x0 code snippet
> - Instead of checking the board variant in the reset routine to
> figure out how to tweak the reset controller, have a compatible
> string for each syscon variant, map it to an enum that provides a
> unique type ID and that way figure out how to handle it in a maybe
> more elegant way.
> - Open issue: what do to with the l2x0 stuff?
> ---
> Documentation/devicetree/bindings/arm/arm-boards | 57 ++++++
> Documentation/devicetree/bindings/arm/gic.txt | 1 +
> arch/arm/boot/dts/Makefile | 1 +
> arch/arm/boot/dts/arm-realview-pb1176.dts | 177 ++++++++++++++++++
> arch/arm/mach-realview/Kconfig | 10 +
> arch/arm/mach-realview/Makefile | 1 +
> arch/arm/mach-realview/realview-dt.c | 225 +++++++++++++++++++++++
> arch/arm/mm/Kconfig | 2 +-
> drivers/irqchip/irq-gic.c | 1 +
> 9 files changed, 474 insertions(+), 1 deletion(-)
> create mode 100644 arch/arm/boot/dts/arm-realview-pb1176.dts
> create mode 100644 arch/arm/mach-realview/realview-dt.c
>
> diff --git a/Documentation/devicetree/bindings/arm/arm-boards b/Documentation/devicetree/bindings/arm/arm-boards
> index 3509707f9320..86b36f399d1c 100644
> --- a/Documentation/devicetree/bindings/arm/arm-boards
> +++ b/Documentation/devicetree/bindings/arm/arm-boards
> @@ -86,3 +86,60 @@ Interrupt controllers:
> compatible = "arm,versatile-sic";
> interrupt-controller;
> #interrupt-cells = <1>;
> +
> +
> +ARM RealView Boards
> +-------------------
> +The RealView boards cover tailored evaluation boards that are used to explore
> +the ARM11 and Cortex A-8 and Cortex A-9 processors.
> +
> +Required properties (in root node):
> + /* RealView Emulation Baseboard */
> + compatible = "arm,realview-eb";
> + /* RealView Platform Baseboard for ARM1176JZF-S */
> + compatible = "arm,realview-pb1176";
> + /* RealView Platform Baseboard for ARM11 MPCore */
> + compatible = "arm,realview-pb11mp";
> + /* RealView Platform Baseboard for Cortex A-8 */
> + compatible = "arm,realview-pba8";
> + /* RealView Platform Baseboard Explore for Cortex A-9 */
> + compatible = "arm,realview-pbx";
> +
> +Required nodes:
> +
> +- syscon: some node of the RealView platforms must have a
> + system controller node pointing to the control registers,
> + with the compatible string set to one of these tuples:
> + "arm,realview-eb-syscon", "syscon"
> + "arm,realview-pb1176-syscon", "syscon"
> + "arm,realview-pb11mp-syscon", "syscon"
> + "arm,realview-pba8-syscon", "syscon"
> + "arm,realview-pbx-syscon", "syscon"
> +
> + Required properties for the system controller:
> + - regs: the location and size of the system controller registers,
> + one range of 0x1000 bytes.
> +
> +Example:
> +
> +/dts-v1/;
> +#include <dt-bindings/interrupt-controller/irq.h>
> +#include "skeleton.dtsi"
> +
> +/ {
> + model = "ARM RealView PB1176 with device tree";
> + compatible = "arm,realview-pb1176";
> +
> + soc {
> + #address-cells = <1>;
> + #size-cells = <1>;
> + compatible = "simple-bus";
> + ranges;
> +
> + syscon: syscon at 10000000 {
> + compatible = "arm,realview-syscon", "syscon";
> + reg = <0x10000000 0x1000>;
> + };
> +
> + };
> +};
> diff --git a/Documentation/devicetree/bindings/arm/gic.txt b/Documentation/devicetree/bindings/arm/gic.txt
> index 5573c08d3180..539420194efd 100644
> --- a/Documentation/devicetree/bindings/arm/gic.txt
> +++ b/Documentation/devicetree/bindings/arm/gic.txt
> @@ -16,6 +16,7 @@ Main node required properties:
> "arm,cortex-a9-gic"
> "arm,cortex-a7-gic"
> "arm,arm11mp-gic"
> + "arm,arm1176jzf-gic"
> - interrupt-controller : Identifies the node as an interrupt controller
> - #interrupt-cells : Specifies the number of cells needed to encode an
> interrupt source. The type shall be a <u32> and the value shall be 3.
> diff --git a/arch/arm/boot/dts/Makefile b/arch/arm/boot/dts/Makefile
> index 377b7c364033..1419a70026da 100644
> --- a/arch/arm/boot/dts/Makefile
> +++ b/arch/arm/boot/dts/Makefile
> @@ -294,6 +294,7 @@ dtb-$(CONFIG_ARCH_PRIMA2) += prima2-evb.dtb
> dtb-$(CONFIG_ARCH_QCOM) += qcom-msm8660-surf.dtb \
> qcom-msm8960-cdp.dtb \
> qcom-apq8074-dragonboard.dtb
> +dtb-$(CONFIG_ARCH_REALVIEW) += arm-realview-pb1176.dtb
> dtb-$(CONFIG_ARCH_S3C24XX) += s3c2416-smdk2416.dtb
> dtb-$(CONFIG_ARCH_S3C64XX) += s3c6410-mini6410.dtb \
> s3c6410-smdk6410.dtb
> diff --git a/arch/arm/boot/dts/arm-realview-pb1176.dts b/arch/arm/boot/dts/arm-realview-pb1176.dts
> new file mode 100644
> index 000000000000..0eea0f4a7b39
> --- /dev/null
> +++ b/arch/arm/boot/dts/arm-realview-pb1176.dts
> @@ -0,0 +1,177 @@
> +/*
> + * Copyright 2014 Linaro Ltd
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a copy
> + * of this software and associated documentation files (the "Software"), to deal
> + * in the Software without restriction, including without limitation the rights
> + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
> + * copies of the Software, and to permit persons to whom the Software is
> + * furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
> + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
> + * THE SOFTWARE.
> + */
> +
> +/dts-v1/;
> +#include <dt-bindings/interrupt-controller/irq.h>
> +#include "skeleton.dtsi"
> +
> +/ {
> + model = "ARM RealView PB1176 with device tree";
Isn't "with device tree" redundant?
> + compatible = "arm,realview-pb1176";
> +
> + chosen { };
> +
> + aliases {
> + serial0 = &pb1176_serial0;
> + serial1 = &pb1176_serial1;
> + serial2 = &pb1176_serial2;
> + serial3 = &pb1176_serial3;
> + };
> +
> + memory {
> + /* 128 MiB memory @ 0x0 */
> + reg = <0x00000000 0x08000000>;
> + };
> +
> + xtal24mhz: xtal24mhz at 24M {
> + #clock-cells = <0>;
> + compatible = "fixed-clock";
> + clock-frequency = <24000000>;
> + };
> +
> + timclk: timclk at 1M {
> + #clock-cells = <0>;
> + compatible = "fixed-factor-clock";
> + clock-div = <24>;
> + clock-mult = <1>;
> + clocks = <&xtal24mhz>;
> + };
> +
> + uartclk: uartclk at 24M {
> + #clock-cells = <0>;
> + compatible = "fixed-factor-clock";
> + clock-div = <1>;
> + clock-mult = <1>;
> + clocks = <&xtal24mhz>;
> + };
> +
> + /* FIXME: this actually hangs off the PLL clocks */
> + pclk: pclk at 0 {
> + #clock-cells = <0>;
> + compatible = "fixed-clock";
> + clock-frequency = <0>;
> + };
> +
> + soc {
> + #address-cells = <1>;
> + #size-cells = <1>;
> + compatible = "simple-bus";
> + ranges;
> +
> + syscon: syscon at 10000000 {
> + compatible = "arm,realview-pb1176-syscon", "syscon";
> + reg = <0x10000000 0x1000>;
> + };
> +
> + /* Primary DevChip GIC synthesized with the CPU */
> + intc_dc1176: interrupt-controller at 10120000 {
> + compatible = "arm,arm1176jzf-gic";
> + #interrupt-cells = <3>;
> + #address-cells = <1>;
> + interrupt-controller;
> + reg = <0x10121000 0x1000>,
> + <0x10120000 0x100>;
> + };
> +
> + /* This GIC on the board is cascaded off the DevChip GIC */
> + intc_pb1176: interrupt-controller at 10040000 {
> + compatible = "arm,arm1176jzf-gic";
> + #interrupt-cells = <3>;
> + #address-cells = <1>;
> + interrupt-controller;
> + reg = <0x10041000 0x1000>,
> + <0x10040000 0x100>;
> + interrupt-parent = <&intc_dc1176>;
> + interrupts = <0 31 IRQ_TYPE_LEVEL_HIGH>;
> + };
> +
> + L2: l2-cache {
> + compatible = "arm,l220-cache";
> + reg = <0x10110000 0x1000>;
> + interrupt-parent = <&intc_dc1176>;
> + interrupts = <0 13 IRQ_TYPE_LEVEL_HIGH>;
> + cache-unified;
> + cache-level = <2>;
> + };
> +
> + pmu {
> + compatible = "arm,arm1176-pmu";
> + interrupt-parent = <&intc_dc1176>;
> + interrupts = <0 7 IRQ_TYPE_LEVEL_HIGH>;
> + };
> +
> + timer01: timer at 10104000 {
> + compatible = "arm,sp804", "arm,primecell";
> + reg = <0x10104000 0x1000>;
> + interrupt-parent = <&intc_dc1176>;
> + interrupts = <0 8 IRQ_TYPE_LEVEL_HIGH>, <0 9 IRQ_TYPE_LEVEL_HIGH>;
> + clocks = <&timclk>, <&timclk>, <&pclk>;
> + clock-names = "timer1", "timer2", "apb_pclk";
> + };
> +
> + timer23: timer at 10105000 {
> + compatible = "arm,sp804", "arm,primecell";
> + reg = <0x10105000 0x1000>;
> + interrupt-parent = <&intc_dc1176>;
> + interrupts = <0 10 IRQ_TYPE_LEVEL_HIGH>;
> + arm,sp804-has-irq = <1>;
> + clocks = <&timclk>, <&timclk>, <&pclk>;
> + clock-names = "timer1", "timer2", "apb_pclk";
> + };
> +
> + pb1176_serial0: uart at 1010c000 {
> + compatible = "arm,pl011", "arm,primecell";
> + reg = <0x1010c000 0x1000>;
> + interrupt-parent = <&intc_dc1176>;
> + interrupts = <0 18 IRQ_TYPE_LEVEL_HIGH>;
> + clocks = <&uartclk>, <&pclk>;
> + clock-names = "uartclk", "apb_pclk";
> + };
> +
> + pb1176_serial1: uart at 1010d000 {
> + compatible = "arm,pl011", "arm,primecell";
> + reg = <0x1010d000 0x1000>;
> + interrupt-parent = <&intc_dc1176>;
> + interrupts = <0 19 IRQ_TYPE_LEVEL_HIGH>;
> + clocks = <&uartclk>, <&pclk>;
> + clock-names = "uartclk", "apb_pclk";
> + };
> +
> + pb1176_serial2: uart at 1010e000 {
> + compatible = "arm,pl011", "arm,primecell";
> + reg = <0x1010e000 0x1000>;
> + interrupt-parent = <&intc_dc1176>;
> + interrupts = <0 20 IRQ_TYPE_LEVEL_HIGH>;
> + clocks = <&uartclk>, <&pclk>;
> + clock-names = "uartclk", "apb_pclk";
> + };
> +
> + pb1176_serial3: uart at 1010f000 {
> + compatible = "arm,pl011", "arm,primecell";
> + reg = <0x1010f000 0x1000>;
> + interrupt-parent = <&intc_dc1176>;
> + interrupts = <0 21 IRQ_TYPE_LEVEL_HIGH>;
> + clocks = <&uartclk>, <&pclk>;
> + clock-names = "uartclk", "apb_pclk";
> + };
> + };
> +};
> diff --git a/arch/arm/mach-realview/Kconfig b/arch/arm/mach-realview/Kconfig
> index 9db2029aa632..65a07f5b5225 100644
> --- a/arch/arm/mach-realview/Kconfig
> +++ b/arch/arm/mach-realview/Kconfig
> @@ -1,6 +1,16 @@
> menu "RealView platform type"
> depends on ARCH_REALVIEW
>
> +config REALVIEW_DT
> + bool "Support RealView(R) Device Tree based boot"
> + select ARM_GIC
> + select MFD_SYSCON
> + select SOC_BUS
> + select USE_OF
> + help
> + Include support for booting the ARM(R) RealView(R) evaluation
> + boards using a device tree machine description.
> +
> config MACH_REALVIEW_EB
> bool "Support RealView(R) Emulation Baseboard"
> select ARM_GIC
> diff --git a/arch/arm/mach-realview/Makefile b/arch/arm/mach-realview/Makefile
> index 541fa4c109ef..e07fdf7ae8a7 100644
> --- a/arch/arm/mach-realview/Makefile
> +++ b/arch/arm/mach-realview/Makefile
> @@ -3,6 +3,7 @@
> #
>
> obj-y := core.o
> +obj-$(CONFIG_REALVIEW_DT) += realview-dt.o
> obj-$(CONFIG_MACH_REALVIEW_EB) += realview_eb.o
> obj-$(CONFIG_MACH_REALVIEW_PB11MP) += realview_pb11mp.o
> obj-$(CONFIG_MACH_REALVIEW_PB1176) += realview_pb1176.o
> diff --git a/arch/arm/mach-realview/realview-dt.c b/arch/arm/mach-realview/realview-dt.c
> new file mode 100644
> index 000000000000..4ba7c5303d09
> --- /dev/null
> +++ b/arch/arm/mach-realview/realview-dt.c
> @@ -0,0 +1,225 @@
> +/*
> + * Copyright (C) 2014 Linaro Ltd.
> + *
> + * Author: Linus Walleij <linus.walleij at linaro.org>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2, as
> + * published by the Free Software Foundation.
> + *
> + */
> +#include <linux/init.h>
> +#include <linux/io.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/irqchip.h>
> +#include <linux/irqchip/arm-gic.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/regmap.h>
> +#include <linux/sys_soc.h>
> +#include <linux/slab.h>
> +#include <asm/mach/map.h>
> +#include <asm/mach/arch.h>
> +#include <asm/hardware/cache-l2x0.h>
> +#include <mach/hardware.h>
> +#include <mach/platform.h>
> +#include <mach/board-eb.h>
> +#include <mach/board-pb1176.h>
> +#include <mach/board-pb11mp.h>
> +#include <mach/board-pbx.h>
> +#include "core.h"
> +
> +/* Pointer to the system controller */
> +struct regmap *syscon_regmap;
> +u8 syscon_type;
> +
> +static struct map_desc realview_dt_io_desc[] __initdata = {
> + {
> + /* FIXME: static map needed for LED driver */
Don't you have patches to fix this? I need them for Versatile
conversion as well.
> + .virtual = IO_ADDRESS(REALVIEW_SYS_BASE),
> + .pfn = __phys_to_pfn(REALVIEW_SYS_BASE),
> + .length = SZ_4K,
> + .type = MT_DEVICE,
> + },
> +};
> +
> +static void __init realview_dt_map_io(void)
> +{
> + iotable_init(realview_dt_io_desc, ARRAY_SIZE(realview_dt_io_desc));
> +}
> +
> +/*
> + * We detect the different syscon types from the compatible strings.
> + */
> +enum realview_syscon {
> + REALVIEW_SYSCON_EB,
> + REALVIEW_SYSCON_PB1176,
> + REALVIEW_SYSCON_PB11MP,
> + REALVIEW_SYSCON_PBA8,
> + REALVIEW_SYSCON_PBX,
> +};
> +
> +static const struct of_device_id realview_syscon_match[] = {
> + {
> + .compatible = "arm,realview-eb-syscon",
> + .data = (void *)REALVIEW_SYSCON_EB,
> + },
> + {
> + .compatible = "arm,realview-pb1176-syscon",
> + .data = (void *)REALVIEW_SYSCON_PB1176,
> + },
> + {
> + .compatible = "arm,realview-pb11mp-syscon",
> + .data = (void *)REALVIEW_SYSCON_PB11MP,
> + },
> + {
> + .compatible = "arm,realview-pba8-syscon",
> + .data = (void *)REALVIEW_SYSCON_PBA8,
> + },
> + {
> + .compatible = "arm,realview-pbx-syscon",
> + .data = (void *)REALVIEW_SYSCON_PBX,
> + },
> +};
> +
> +static void __init realview_dt_init_machine(void)
> +{
> + struct device_node *root;
> + struct device_node *syscon;
> + const struct of_device_id *syscon_id;
> + struct soc_device *soc_dev;
> + struct soc_device_attribute *soc_dev_attr;
> + struct device *parent;
> + u32 coreid;
> + int ret;
> +
> +#if IS_ENABLED(CONFIG_CACHE_L2X0)
> + if (of_machine_is_compatible("arm,realview-eb"))
> + /*
> + * 1MB (128KB/way), 8-way associativity,
These should go into DT properties. Cache attributes are already
defined in ePAPR.
> + * evmon/parity/share enabled
These can probably be unconditionally enabled except for parity which
could be a DT property.
> + * Bits: .... ...0 0111 1001 0000 .... .... ....
> + */
> + l2x0_of_init(0x00790000, 0xfe000fff);
> + else if (of_machine_is_compatible("arm,realview-pb1176"))
> + /*
> + * 128Kb (16Kb/way) 8-way associativity.
> + * evmon/parity/share enabled.
> + */
> + l2x0_of_init(0x00730000, 0xfe000fff);
> + else if (of_machine_is_compatible("arm,realview-pb11mp"))
> + /*
> + * 1MB (128KB/way), 8-way associativity,
> + * evmon/parity/share enabled
> + * Bits: .... ...0 0111 1001 0000 .... .... ....
> + */
> + l2x0_of_init(0x00730000, 0xfe000fff);
> + else if (of_machine_is_compatible("arm,realview-pbx"))
> + /*
> + * 16KB way size, 8-way associativity, parity disabled
> + * Bits: .. 0 0 0 0 1 00 1 0 1 001 0 000 0 .... .... ....
> + */
> + l2x0_of_init(0x02520000, 0xc0000fff);
> +#endif
> +
> + /* Here we create an SoC device for the root node */
> + root = of_find_node_by_path("/");
> + if (!root)
> + return;
> + syscon = of_find_matching_node_and_match(root, realview_syscon_match,
> + &syscon_id);
> + if (!syscon)
> + return;
> + syscon_type = (enum realview_syscon)syscon_id->data;
> +
> + soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
> + if (!soc_dev_attr)
> + return;
> + ret = of_property_read_string(root, "compatible",
> + &soc_dev_attr->soc_id);
> + if (ret)
> + return;
> + ret = of_property_read_string(root, "model", &soc_dev_attr->machine);
> + if (ret)
> + return;
> + soc_dev_attr->family = "RealView";
> + soc_dev = soc_device_register(soc_dev_attr);
> + if (IS_ERR(soc_dev)) {
> + kfree(soc_dev_attr);
> + return;
> + }
> + parent = soc_device_to_device(soc_dev);
We really need to standardize this soc device stuff so that platforms
always have a parent soc device or not.
> + ret = of_platform_populate(root, of_default_bus_match_table,
> + NULL, parent);
> + if (ret) {
> + pr_crit("could not populate device tree\n");
> + return;
> + }
> +
> + syscon_regmap = syscon_node_to_regmap(syscon);
> + if (IS_ERR(syscon_regmap)) {
> + pr_crit("could not locate syscon regmap\n");
> + return;
> + }
> + ret = regmap_read(syscon_regmap, REALVIEW_SYS_ID_OFFSET, &coreid);
> + if (ret)
> + return;
> + pr_info("RealView Syscon type %02x, Core ID: 0x%08x\n",
> + syscon_type, coreid);
> + /* FIXME: add attributes for SoC to sysfs */
> +}
> +
> +static void realview_dt_restart(enum reboot_mode mode, const char *cmd)
> +{
> + if (IS_ERR(syscon_regmap))
> + return;
> +
> + /* Unlock the reset register */
> + regmap_write(syscon_regmap, REALVIEW_SYS_LOCK_OFFSET,
> + REALVIEW_SYS_LOCK_VAL);
> + /* Then hit reset on the different machines */
> + switch (syscon_type) {
> + case REALVIEW_SYSCON_EB:
> + regmap_write(syscon_regmap,
> + REALVIEW_SYS_RESETCTL_OFFSET, 0x0008);
> + break;
> + case REALVIEW_SYSCON_PB1176:
> + regmap_write(syscon_regmap,
> + REALVIEW_SYS_RESETCTL_OFFSET, 0x0100);
> + break;
> + case REALVIEW_SYSCON_PB11MP:
> + case REALVIEW_SYSCON_PBA8:
> + regmap_write(syscon_regmap, REALVIEW_SYS_RESETCTL_OFFSET,
> + 0x0000);
> + regmap_write(syscon_regmap, REALVIEW_SYS_RESETCTL_OFFSET,
> + 0x0004);
> + break;
> + case REALVIEW_SYSCON_PBX:
> + regmap_write(syscon_regmap, REALVIEW_SYS_RESETCTL_OFFSET,
> + 0x00f0);
> + regmap_write(syscon_regmap, REALVIEW_SYS_RESETCTL_OFFSET,
> + 0x00f4);
> + break;
> + }
> + dsb();
Barriers need comments as to why they are needed.
Rob
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