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Commit adf20d7c authored by Philipp Zabel's avatar Philipp Zabel
Browse files

reset: socfpga: use the reset-simple driver



Add reset line status readback, inverted status support, and socfpga
device tree quirks to the simple reset driver, and use it to replace
the socfpga driver.

Signed-off-by: default avatarPhilipp Zabel <p.zabel@pengutronix.de>
parent e13c205a
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+2 −8
Original line number Diff line number Diff line
@@ -77,19 +77,13 @@ config RESET_PISTACHIO

config RESET_SIMPLE
	bool "Simple Reset Controller Driver" if COMPILE_TEST
	default ARCH_SUNXI
	default ARCH_SOCFPGA || ARCH_STRATIX10 || ARCH_SUNXI
	help
	  This enables a simple reset controller driver for reset lines that
	  that can be asserted and deasserted by toggling bits in a contiguous,
	  exclusive register space.

	  Currently this driver supports Allwinner SoCs.

config RESET_SOCFPGA
	bool "SoCFPGA Reset Driver" if COMPILE_TEST
	default ARCH_SOCFPGA || ARCH_STRATIX10
	help
	  This enables the reset controller driver for Altera SoCFPGAs.
	  Currently this driver supports Altera SoCFPGAs and Allwinner SoCs.

config RESET_STM32
	bool "STM32 Reset Driver" if COMPILE_TEST
+0 −1
Original line number Diff line number Diff line
@@ -13,7 +13,6 @@ obj-$(CONFIG_RESET_MESON) += reset-meson.o
obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o
obj-$(CONFIG_RESET_PISTACHIO) += reset-pistachio.o
obj-$(CONFIG_RESET_SIMPLE) += reset-simple.o
obj-$(CONFIG_RESET_SOCFPGA) += reset-socfpga.o
obj-$(CONFIG_RESET_STM32) += reset-stm32.o
obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o
obj-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o
+50 −1
Original line number Diff line number Diff line
@@ -68,25 +68,58 @@ static int reset_simple_deassert(struct reset_controller_dev *rcdev,
	return reset_simple_update(rcdev, id, false);
}

static int reset_simple_status(struct reset_controller_dev *rcdev,
			       unsigned long id)
{
	struct reset_simple_data *data = to_reset_simple_data(rcdev);
	int reg_width = sizeof(u32);
	int bank = id / (reg_width * BITS_PER_BYTE);
	int offset = id % (reg_width * BITS_PER_BYTE);
	u32 reg;

	reg = readl(data->membase + (bank * reg_width));

	return !(reg & BIT(offset)) ^ !data->status_active_low;
}

const struct reset_control_ops reset_simple_ops = {
	.assert		= reset_simple_assert,
	.deassert	= reset_simple_deassert,
	.status		= reset_simple_status,
};

/**
 * struct reset_simple_devdata - simple reset controller properties
 * @reg_offset: offset between base address and first reset register.
 * @nr_resets: number of resets. If not set, default to resource size in bits.
 * @active_low: if true, bits are cleared to assert the reset. Otherwise, bits
 *              are set to assert the reset.
 * @status_active_low: if true, bits read back as cleared while the reset is
 *                     asserted. Otherwise, bits read back as set while the
 *                     reset is asserted.
 */
struct reset_simple_devdata {
	u32 reg_offset;
	u32 nr_resets;
	bool active_low;
	bool status_active_low;
};

#define SOCFPGA_NR_BANKS	8

static const struct reset_simple_devdata reset_simple_socfpga = {
	.reg_offset = 0x10,
	.nr_resets = SOCFPGA_NR_BANKS * 32,
	.status_active_low = true,
};

static const struct reset_simple_devdata reset_simple_active_low = {
	.active_low = true,
	.status_active_low = true,
};

static const struct of_device_id reset_simple_dt_ids[] = {
	{ .compatible = "altr,rst-mgr", .data = &reset_simple_socfpga },
	{ .compatible = "allwinner,sun6i-a31-clock-reset",
		.data = &reset_simple_active_low },
	{ /* sentinel */ },
@@ -99,6 +132,7 @@ static int reset_simple_probe(struct platform_device *pdev)
	struct reset_simple_data *data;
	void __iomem *membase;
	struct resource *res;
	u32 reg_offset = 0;

	devdata = of_device_get_match_data(dev);

@@ -118,8 +152,23 @@ static int reset_simple_probe(struct platform_device *pdev)
	data->rcdev.ops = &reset_simple_ops;
	data->rcdev.of_node = dev->of_node;

	if (devdata)
	if (devdata) {
		reg_offset = devdata->reg_offset;
		if (devdata->nr_resets)
			data->rcdev.nr_resets = devdata->nr_resets;
		data->active_low = devdata->active_low;
		data->status_active_low = devdata->status_active_low;
	}

	if (of_device_is_compatible(dev->of_node, "altr,rst-mgr") &&
	    of_property_read_u32(dev->of_node, "altr,modrst-offset",
				 &reg_offset)) {
		dev_warn(dev,
			 "missing altr,modrst-offset property, assuming 0x%x!\n",
			 reg_offset);
	}

	data->membase += reg_offset;

	return devm_reset_controller_register(dev, &data->rcdev);
}
+4 −0
Original line number Diff line number Diff line
@@ -28,12 +28,16 @@
 * @active_low: if true, bits are cleared to assert the reset. Otherwise, bits
 *              are set to assert the reset. Note that this says nothing about
 *              the voltage level of the actual reset line.
 * @status_active_low: if true, bits read back as cleared while the reset is
 *                     asserted. Otherwise, bits read back as set while the
 *                     reset is asserted.
 */
struct reset_simple_data {
	spinlock_t			lock;
	void __iomem			*membase;
	struct reset_controller_dev	rcdev;
	bool				active_low;
	bool				status_active_low;
};

extern const struct reset_control_ops reset_simple_ops;

drivers/reset/reset-socfpga.c

deleted100644 → 0
+0 −157
Original line number Diff line number Diff line
/*
 * Socfpga Reset Controller Driver
 *
 * Copyright 2014 Steffen Trumtrar <s.trumtrar@pengutronix.de>
 *
 * based on
 * Allwinner SoCs Reset Controller driver
 *
 * Copyright 2013 Maxime Ripard
 *
 * Maxime Ripard <maxime.ripard@free-electrons.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/err.h>
#include <linux/io.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/reset-controller.h>
#include <linux/spinlock.h>
#include <linux/types.h>

#define BANK_INCREMENT		4
#define NR_BANKS		8

struct socfpga_reset_data {
	spinlock_t			lock;
	void __iomem			*membase;
	struct reset_controller_dev	rcdev;
};

static int socfpga_reset_assert(struct reset_controller_dev *rcdev,
				unsigned long id)
{
	struct socfpga_reset_data *data = container_of(rcdev,
						     struct socfpga_reset_data,
						     rcdev);
	int reg_width = sizeof(u32);
	int bank = id / (reg_width * BITS_PER_BYTE);
	int offset = id % (reg_width * BITS_PER_BYTE);
	unsigned long flags;
	u32 reg;

	spin_lock_irqsave(&data->lock, flags);

	reg = readl(data->membase + (bank * BANK_INCREMENT));
	writel(reg | BIT(offset), data->membase + (bank * BANK_INCREMENT));
	spin_unlock_irqrestore(&data->lock, flags);

	return 0;
}

static int socfpga_reset_deassert(struct reset_controller_dev *rcdev,
				  unsigned long id)
{
	struct socfpga_reset_data *data = container_of(rcdev,
						     struct socfpga_reset_data,
						     rcdev);

	int reg_width = sizeof(u32);
	int bank = id / (reg_width * BITS_PER_BYTE);
	int offset = id % (reg_width * BITS_PER_BYTE);
	unsigned long flags;
	u32 reg;

	spin_lock_irqsave(&data->lock, flags);

	reg = readl(data->membase + (bank * BANK_INCREMENT));
	writel(reg & ~BIT(offset), data->membase + (bank * BANK_INCREMENT));

	spin_unlock_irqrestore(&data->lock, flags);

	return 0;
}

static int socfpga_reset_status(struct reset_controller_dev *rcdev,
				unsigned long id)
{
	struct socfpga_reset_data *data = container_of(rcdev,
						struct socfpga_reset_data, rcdev);
	int reg_width = sizeof(u32);
	int bank = id / (reg_width * BITS_PER_BYTE);
	int offset = id % (reg_width * BITS_PER_BYTE);
	u32 reg;

	reg = readl(data->membase + (bank * BANK_INCREMENT));

	return !(reg & BIT(offset));
}

static const struct reset_control_ops socfpga_reset_ops = {
	.assert		= socfpga_reset_assert,
	.deassert	= socfpga_reset_deassert,
	.status		= socfpga_reset_status,
};

static int socfpga_reset_probe(struct platform_device *pdev)
{
	struct socfpga_reset_data *data;
	struct resource *res;
	struct device *dev = &pdev->dev;
	struct device_node *np = dev->of_node;
	u32 modrst_offset;

	/*
	 * The binding was mainlined without the required property.
	 * Do not continue, when we encounter an old DT.
	 */
	if (!of_find_property(pdev->dev.of_node, "#reset-cells", NULL)) {
		dev_err(&pdev->dev, "%pOF missing #reset-cells property\n",
			pdev->dev.of_node);
		return -EINVAL;
	}

	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	data->membase = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(data->membase))
		return PTR_ERR(data->membase);

	if (of_property_read_u32(np, "altr,modrst-offset", &modrst_offset)) {
		dev_warn(dev, "missing altr,modrst-offset property, assuming 0x10!\n");
		modrst_offset = 0x10;
	}
	data->membase += modrst_offset;

	spin_lock_init(&data->lock);

	data->rcdev.owner = THIS_MODULE;
	data->rcdev.nr_resets = NR_BANKS * (sizeof(u32) * BITS_PER_BYTE);
	data->rcdev.ops = &socfpga_reset_ops;
	data->rcdev.of_node = pdev->dev.of_node;

	return devm_reset_controller_register(dev, &data->rcdev);
}

static const struct of_device_id socfpga_reset_dt_ids[] = {
	{ .compatible = "altr,rst-mgr", },
	{ /* sentinel */ },
};

static struct platform_driver socfpga_reset_driver = {
	.probe	= socfpga_reset_probe,
	.driver = {
		.name		= "socfpga-reset",
		.of_match_table	= socfpga_reset_dt_ids,
	},
};
builtin_platform_driver(socfpga_reset_driver);