mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-30 15:44:13 +08:00
5a2308da9f
Add a reset controller driver for the Canaan Kendryte K210 SoC. This driver relies on its syscon compatible parent node (sysctl) for its register mapping. Default this driver compilation to y when the SOC_CANAAN option is selected. The MAINTAINERS file is updated, adding the entry "CANAAN/KENDRYTE K210 SOC RESET CONTROLLER DRIVER" with myself listed as maintainer for this driver. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
132 lines
3.0 KiB
C
132 lines
3.0 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Copyright (c) 2020 Western Digital Corporation or its affiliates.
|
|
*/
|
|
#include <linux/of.h>
|
|
#include <linux/of_device.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/reset-controller.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/mfd/syscon.h>
|
|
#include <linux/regmap.h>
|
|
#include <soc/canaan/k210-sysctl.h>
|
|
|
|
#include <dt-bindings/reset/k210-rst.h>
|
|
|
|
#define K210_RST_MASK 0x27FFFFFF
|
|
|
|
struct k210_rst {
|
|
struct regmap *map;
|
|
struct reset_controller_dev rcdev;
|
|
};
|
|
|
|
static inline struct k210_rst *
|
|
to_k210_rst(struct reset_controller_dev *rcdev)
|
|
{
|
|
return container_of(rcdev, struct k210_rst, rcdev);
|
|
}
|
|
|
|
static inline int k210_rst_assert(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
struct k210_rst *ksr = to_k210_rst(rcdev);
|
|
|
|
return regmap_update_bits(ksr->map, K210_SYSCTL_PERI_RESET, BIT(id), 1);
|
|
}
|
|
|
|
static inline int k210_rst_deassert(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
struct k210_rst *ksr = to_k210_rst(rcdev);
|
|
|
|
return regmap_update_bits(ksr->map, K210_SYSCTL_PERI_RESET, BIT(id), 0);
|
|
}
|
|
|
|
static int k210_rst_reset(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
int ret;
|
|
|
|
ret = k210_rst_assert(rcdev, id);
|
|
if (ret == 0) {
|
|
udelay(10);
|
|
ret = k210_rst_deassert(rcdev, id);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int k210_rst_status(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
struct k210_rst *ksr = to_k210_rst(rcdev);
|
|
u32 reg, bit = BIT(id);
|
|
int ret;
|
|
|
|
ret = regmap_read(ksr->map, K210_SYSCTL_PERI_RESET, ®);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return reg & bit;
|
|
}
|
|
|
|
static int k210_rst_xlate(struct reset_controller_dev *rcdev,
|
|
const struct of_phandle_args *reset_spec)
|
|
{
|
|
unsigned long id = reset_spec->args[0];
|
|
|
|
if (!(BIT(id) & K210_RST_MASK))
|
|
return -EINVAL;
|
|
|
|
return id;
|
|
}
|
|
|
|
static const struct reset_control_ops k210_rst_ops = {
|
|
.assert = k210_rst_assert,
|
|
.deassert = k210_rst_deassert,
|
|
.reset = k210_rst_reset,
|
|
.status = k210_rst_status,
|
|
};
|
|
|
|
static int k210_rst_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct device_node *parent_np = of_get_parent(dev->of_node);
|
|
struct k210_rst *ksr;
|
|
|
|
dev_info(dev, "K210 reset controller\n");
|
|
|
|
ksr = devm_kzalloc(dev, sizeof(*ksr), GFP_KERNEL);
|
|
if (!ksr)
|
|
return -ENOMEM;
|
|
|
|
ksr->map = syscon_node_to_regmap(parent_np);
|
|
of_node_put(parent_np);
|
|
if (IS_ERR(ksr->map))
|
|
return PTR_ERR(ksr->map);
|
|
|
|
ksr->rcdev.owner = THIS_MODULE;
|
|
ksr->rcdev.dev = dev;
|
|
ksr->rcdev.of_node = dev->of_node;
|
|
ksr->rcdev.ops = &k210_rst_ops;
|
|
ksr->rcdev.nr_resets = fls(K210_RST_MASK);
|
|
ksr->rcdev.of_reset_n_cells = 1;
|
|
ksr->rcdev.of_xlate = k210_rst_xlate;
|
|
|
|
return devm_reset_controller_register(dev, &ksr->rcdev);
|
|
}
|
|
|
|
static const struct of_device_id k210_rst_dt_ids[] = {
|
|
{ .compatible = "canaan,k210-rst" },
|
|
{ /* sentinel */ },
|
|
};
|
|
|
|
static struct platform_driver k210_rst_driver = {
|
|
.probe = k210_rst_probe,
|
|
.driver = {
|
|
.name = "k210-rst",
|
|
.of_match_table = k210_rst_dt_ids,
|
|
},
|
|
};
|
|
builtin_platform_driver(k210_rst_driver);
|