ARC AXS10x boards support custom IP-block which allows to control reset signals of selected peripherals. For example DW GMAC, etc... This block is controlled via memory-mapped register (AKA CREG) which represents up-to 32 reset lines. As of today only the following lines are used: - DW GMAC - line 5 Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx> --- .../bindings/reset/snps,axs10x-reset.txt | 34 +++++++ MAINTAINERS | 6 ++ drivers/reset/Kconfig | 6 ++ drivers/reset/Makefile | 1 + drivers/reset/reset-axs10x.c | 109 +++++++++++++++++++++ 5 files changed, 156 insertions(+) create mode 100644 Documentation/devicetree/bindings/reset/snps,axs10x-reset.txt create mode 100644 drivers/reset/reset-axs10x.c diff --git a/Documentation/devicetree/bindings/reset/snps,axs10x-reset.txt b/Documentation/devicetree/bindings/reset/snps,axs10x-reset.txt new file mode 100644 index 0000000..32eed7a --- /dev/null +++ b/Documentation/devicetree/bindings/reset/snps,axs10x-reset.txt @@ -0,0 +1,34 @@ +Binding for the AXS10x reset controller + +This binding describes the ARC AXS10x boards custom IP-block which allows +to control reset signals of selected peripherals. For example DW GMAC, etc... +This block is controlled via memory-mapped register (AKA CREG) which +represents up-to 32 reset lines. + +As of today only the following lines are used: + - DW GMAC - line 5 + +This binding uses the common reset binding[1]. + +[1] Documentation/devicetree/bindings/reset/reset.txt + +Required properties: +- compatible: should be "snps,axs10x-reset". +- reg: should always contain pair address - length: for creg reset + bits register. +- #reset-cells: from common reset binding; Should always be set to 1. + +Example: + reset: reset@11220 { + compatible = "snps,axs10x-reset"; + #reset-cells = <1>; + reg = <0x11220 0x4>; + }; + +Specifying reset lines connected to IP modules: + ethernet@.... { + .... + resets = <&reset 5>; + .... + }; + diff --git a/MAINTAINERS b/MAINTAINERS index 93dfb9d..f14e804 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12711,6 +12711,12 @@ F: arch/arc/plat-axs10x F: arch/arc/boot/dts/ax* F: Documentation/devicetree/bindings/arc/axs10* +SYNOPSYS AXS10x RESET CONTROLLER DRIVER +M: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx> +S: Supported +F: drivers/reset/reset-axs10x.c +F: Documentation/devicetree/bindings/reset/snps,axs10x-reset.txt + SYNOPSYS DESIGNWARE DMAC DRIVER M: Viresh Kumar <vireshk@xxxxxxxxxx> M: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index 52d5251..65d13f4 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -28,6 +28,12 @@ config RESET_ATH79 This enables the ATH79 reset controller driver that supports the AR71xx SoC reset controller. +config RESET_AXS10X + bool "AXS10x Reset Driver" if COMPILE_TEST + default ARC_PLAT_AXS10X + help + This enables the reset controller driver for AXS10x. + config RESET_BERLIN bool "Berlin Reset Driver" if COMPILE_TEST default ARCH_BERLIN diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index b62783f..45000a5 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -4,6 +4,7 @@ obj-$(CONFIG_ARCH_STI) += sti/ obj-$(CONFIG_ARCH_TEGRA) += tegra/ obj-$(CONFIG_RESET_A10SR) += reset-a10sr.o obj-$(CONFIG_RESET_ATH79) += reset-ath79.o +obj-$(CONFIG_RESET_AXS10X) += reset-axs10x.o obj-$(CONFIG_RESET_BERLIN) += reset-berlin.o obj-$(CONFIG_RESET_HSDK_V1) += reset-hsdk-v1.o obj-$(CONFIG_RESET_IMX7) += reset-imx7.o diff --git a/drivers/reset/reset-axs10x.c b/drivers/reset/reset-axs10x.c new file mode 100644 index 0000000..17a4cb4 --- /dev/null +++ b/drivers/reset/reset-axs10x.c @@ -0,0 +1,109 @@ +/* + * Copyright (C) 2017 Synopsys. + * + * Synopsys AXS10x reset driver. + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reset-controller.h> +#include <linux/slab.h> +#include <linux/types.h> + +#define to_axs10x_rst(p) container_of((p), struct axs10x_rst, rcdev) + +#define AXS10X_MAX_RESETS 32 + +struct axs10x_rst { + void __iomem *regs_rst; + spinlock_t lock; + struct reset_controller_dev rcdev; +}; + +static int axs10x_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct axs10x_rst *rst = to_axs10x_rst(rcdev); + unsigned long flags; + u32 reg; + + spin_lock_irqsave(&rst->lock, flags); + reg = readl(rst->regs_rst); + reg |= BIT(id); + writel(reg, rst->regs_rst); + spin_unlock_irqrestore(&rst->lock, flags); + + return 0; +} + +static int axs10x_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct axs10x_rst *rst = to_axs10x_rst(rcdev); + unsigned long flags; + u32 reg; + + spin_lock_irqsave(&rst->lock, flags); + reg = readl(rst->regs_rst); + reg &= ~BIT(id); + writel(reg, rst->regs_rst); + spin_unlock_irqrestore(&rst->lock, flags); + + return 0; +} + +static const struct reset_control_ops axs10x_reset_ops = { + .assert = axs10x_reset_assert, + .deassert = axs10x_reset_deassert, +}; + +static int axs10x_reset_probe(struct platform_device *pdev) +{ + struct axs10x_rst *rst; + struct resource *mem; + + rst = devm_kzalloc(&pdev->dev, sizeof(*rst), GFP_KERNEL); + if (!rst) + return -ENOMEM; + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + rst->regs_rst = devm_ioremap_resource(&pdev->dev, mem); + if (IS_ERR(rst->regs_rst)) + return PTR_ERR(rst->regs_rst); + + spin_lock_init(&rst->lock); + + rst->rcdev.owner = THIS_MODULE; + rst->rcdev.ops = &axs10x_reset_ops; + rst->rcdev.of_node = pdev->dev.of_node; + rst->rcdev.nr_resets = AXS10X_MAX_RESETS; + rst->rcdev.of_reset_n_cells = 1; + + return reset_controller_register(&rst->rcdev); +} + +static const struct of_device_id axs10x_reset_dt_match[] = { + { .compatible = "snps,axs10x-reset" }, + { }, +}; + +static struct platform_driver axs10x_reset_driver = { + .probe = axs10x_reset_probe, + .driver = { + .name = "axs10x-reset", + .of_match_table = axs10x_reset_dt_match, + }, +}; +builtin_platform_driver(axs10x_reset_driver); + +MODULE_AUTHOR("Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Synopsys AXS10x reset driver"); +MODULE_LICENSE("GPL v2"); -- 2.9.3 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html