149 lines
3.6 KiB
C
149 lines
3.6 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright (C) STMicroelectronics 2022 - All Rights Reserved
|
|
* Author: Gabriel Fernandez <gabriel.fernandez@foss.st.com> for STMicroelectronics.
|
|
*/
|
|
|
|
#include <linux/of.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/regmap.h>
|
|
#include <linux/reset-controller.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/spinlock.h>
|
|
|
|
#include "reset-stm32.h"
|
|
|
|
struct stm32_reset_data {
|
|
/* reset lock */
|
|
spinlock_t lock;
|
|
struct reset_controller_dev rcdev;
|
|
void __iomem *membase;
|
|
u32 clear_offset;
|
|
const struct stm32_reset_cfg **reset_lines;
|
|
};
|
|
|
|
static inline struct stm32_reset_data *
|
|
to_stm32_reset_data(struct reset_controller_dev *rcdev)
|
|
{
|
|
return container_of(rcdev, struct stm32_reset_data, rcdev);
|
|
}
|
|
|
|
static const struct stm32_reset_cfg *stm32_get_reset_line(struct reset_controller_dev *rcdev,
|
|
unsigned long id,
|
|
struct stm32_reset_cfg *line)
|
|
{
|
|
struct stm32_reset_data *data = to_stm32_reset_data(rcdev);
|
|
|
|
if (!data->reset_lines) {
|
|
int reg_width = sizeof(u32);
|
|
int bank = id / (reg_width * BITS_PER_BYTE);
|
|
int offset = id % (reg_width * BITS_PER_BYTE);
|
|
|
|
line->offset = bank * reg_width;
|
|
line->bit_idx = offset;
|
|
line->set_clr = (data->clear_offset ? true : false);
|
|
|
|
return line;
|
|
}
|
|
|
|
return data->reset_lines[id];
|
|
}
|
|
|
|
static int stm32_reset_update(struct reset_controller_dev *rcdev,
|
|
unsigned long id, bool assert)
|
|
{
|
|
struct stm32_reset_data *data = to_stm32_reset_data(rcdev);
|
|
struct stm32_reset_cfg line_reset;
|
|
const struct stm32_reset_cfg *ptr_line;
|
|
|
|
ptr_line = stm32_get_reset_line(rcdev, id, &line_reset);
|
|
if (!ptr_line)
|
|
return -EPERM;
|
|
|
|
if (ptr_line->set_clr) {
|
|
void __iomem *addr;
|
|
|
|
addr = data->membase + ptr_line->offset;
|
|
if (!assert)
|
|
addr += data->clear_offset;
|
|
|
|
writel(BIT(ptr_line->bit_idx), addr);
|
|
|
|
} else {
|
|
unsigned long flags;
|
|
u32 reg;
|
|
|
|
spin_lock_irqsave(&data->lock, flags);
|
|
|
|
reg = readl(data->membase + ptr_line->offset);
|
|
|
|
if (assert)
|
|
reg |= BIT(ptr_line->bit_idx);
|
|
else
|
|
reg &= ~BIT(ptr_line->bit_idx);
|
|
|
|
writel(reg, data->membase + ptr_line->offset);
|
|
|
|
spin_unlock_irqrestore(&data->lock, flags);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int stm32_reset_assert(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
return stm32_reset_update(rcdev, id, true);
|
|
}
|
|
|
|
static int stm32_reset_deassert(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
return stm32_reset_update(rcdev, id, false);
|
|
}
|
|
|
|
static int stm32_reset_status(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
struct stm32_reset_data *data = to_stm32_reset_data(rcdev);
|
|
struct stm32_reset_cfg line_reset;
|
|
const struct stm32_reset_cfg *ptr_line;
|
|
u32 reg;
|
|
|
|
ptr_line = stm32_get_reset_line(rcdev, id, &line_reset);
|
|
if (!ptr_line)
|
|
return -EPERM;
|
|
|
|
reg = readl(data->membase + ptr_line->offset);
|
|
|
|
return !!(reg & BIT(ptr_line->bit_idx));
|
|
}
|
|
|
|
static const struct reset_control_ops stm32_reset_ops = {
|
|
.assert = stm32_reset_assert,
|
|
.deassert = stm32_reset_deassert,
|
|
.status = stm32_reset_status,
|
|
};
|
|
|
|
int stm32_rcc_reset_init(struct device *dev, struct clk_stm32_reset_data *data,
|
|
void __iomem *base)
|
|
{
|
|
struct stm32_reset_data *reset_data;
|
|
|
|
reset_data = kzalloc(sizeof(*reset_data), GFP_KERNEL);
|
|
if (!reset_data)
|
|
return -ENOMEM;
|
|
|
|
spin_lock_init(&reset_data->lock);
|
|
|
|
reset_data->membase = base;
|
|
reset_data->rcdev.owner = THIS_MODULE;
|
|
reset_data->rcdev.ops = &stm32_reset_ops;
|
|
reset_data->rcdev.of_node = dev_of_node(dev);
|
|
reset_data->rcdev.nr_resets = data->nr_lines;
|
|
reset_data->reset_lines = data->reset_lines;
|
|
reset_data->clear_offset = data->clear_offset;
|
|
|
|
return reset_controller_register(&reset_data->rcdev);
|
|
}
|