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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* 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>
*/
#include <common.h>
#include <init.h>
#include <io.h>
#include <linux/err.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 bank = id / BITS_PER_LONG;
int offset = id % BITS_PER_LONG;
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 bank = id / BITS_PER_LONG;
int offset = id % BITS_PER_LONG;
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 const struct reset_control_ops socfpga_reset_ops = {
.assert = socfpga_reset_assert,
.deassert = socfpga_reset_deassert,
};
static int socfpga_reset_probe(struct device_d *dev)
{
struct socfpga_reset_data *data;
struct resource *res;
struct device_node *np = dev->device_node;
u32 modrst_offset;
data = xzalloc(sizeof(*data));
res = dev_request_mem_resource(dev, 0);
if (IS_ERR(res))
return PTR_ERR(res);
data->membase = IOMEM(res->start);
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.nr_resets = NR_BANKS * BITS_PER_LONG;
data->rcdev.ops = &socfpga_reset_ops;
data->rcdev.of_node = np;
return reset_controller_register(&data->rcdev);
}
static const struct of_device_id socfpga_reset_dt_ids[] = {
{ .compatible = "altr,rst-mgr", },
{ /* sentinel */ },
};
static struct driver_d socfpga_reset_driver = {
.name = "socfpga_reset",
.probe = socfpga_reset_probe,
.of_compatible = DRV_OF_COMPAT(socfpga_reset_dt_ids),
};
postcore_platform_driver(socfpga_reset_driver);
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