anolis-cloud-kernel/drivers/rtc/rtc-ls2x.c

326 lines
8.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Loongson-2K/7A RTC driver
*
* Based on the original out-of-tree Loongson-2H RTC driver for Linux 2.6.32,
* by Shaozong Liu <liushaozong@loongson.cn>.
*
* Maintained out-of-tree by Huacai Chen <chenhuacai@kernel.org>.
*
* Rewritten for mainline by WANG Xuerui <git@xen0n.name>.
*/
#include <linux/of.h>
#include <linux/rtc.h>
#include <linux/acpi.h>
#include <linux/regmap.h>
#include <linux/module.h>
#include <linux/bitfield.h>
#include <linux/platform_device.h>
#define TOY_TRIM_REG 0x20
#define TOY_WRITE0_REG 0x24
#define TOY_WRITE1_REG 0x28
#define TOY_READ0_REG 0x2c
#define TOY_READ1_REG 0x30
#define TOY_MATCH0_REG 0x34
#define TOY_MATCH1_REG 0x38
#define TOY_MATCH2_REG 0x3c
#define RTC_CTRL_REG 0x40
#define RTC_TRIM_REG 0x60
#define RTC_WRITE0_REG 0x64
#define RTC_READ0_REG 0x68
#define RTC_MATCH0_REG 0x6c
#define RTC_MATCH1_REG 0x70
#define RTC_MATCH2_REG 0x74
#define TOY_MON GENMASK(31, 26)
#define TOY_DAY GENMASK(25, 21)
#define TOY_HOUR GENMASK(20, 16)
#define TOY_MIN GENMASK(15, 10)
#define TOY_SEC GENMASK(9, 4)
#define TOY_MSEC GENMASK(3, 0)
#define TOY_MATCH_YEAR GENMASK(31, 26)
#define TOY_MATCH_MON GENMASK(25, 22)
#define TOY_MATCH_DAY GENMASK(21, 17)
#define TOY_MATCH_HOUR GENMASK(16, 12)
#define TOY_MATCH_MIN GENMASK(11, 6)
#define TOY_MATCH_SEC GENMASK(5, 0)
/* ACPI and RTC offset */
#define ACPI_RTC_OFFSET 0x100
/* support rtc wakeup */
#define ACPI_PM1_STS_REG 0x0c
#define ACPI_PM1_EN_REG 0x10
#define RTC_EN BIT(10)
#define RTC_STS BIT(10)
struct ls2x_rtc_priv {
struct regmap *regmap;
spinlock_t rtc_reglock;
void __iomem *acpi_base;
struct rtc_device *rtcdev;
};
static const struct regmap_config ls2x_rtc_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
};
struct ls2x_rtc_regs {
u32 reg0;
u32 reg1;
};
#if defined(CONFIG_ACPI)
static u32 ls2x_acpi_fix_handler(void *id)
{
int ret;
struct ls2x_rtc_priv *priv = (struct ls2x_rtc_priv *)id;
spin_lock(&priv->rtc_reglock);
/* Disable acpi rtc enabled */
ret = readl(priv->acpi_base + ACPI_PM1_EN_REG) & ~RTC_EN;
writel(ret, priv->acpi_base + ACPI_PM1_EN_REG);
/* Clear acpi rtc interrupt Status */
writel(RTC_STS, priv->acpi_base + ACPI_PM1_STS_REG);
spin_unlock(&priv->rtc_reglock);
/*
* The TOY_MATCH0_REG should be cleared 0 here,
* otherwise the interrupt cannot be cleared.
* Because the match condition is still satisfied
*/
ret = regmap_write(priv->regmap, TOY_MATCH0_REG, 0);
if (unlikely(ret))
return ret;
return 0;
}
#endif
static inline void ls2x_rtc_regs_to_time(struct ls2x_rtc_regs *regs,
struct rtc_time *tm)
{
tm->tm_year = regs->reg1;
tm->tm_sec = FIELD_GET(TOY_SEC, regs->reg0);
tm->tm_min = FIELD_GET(TOY_MIN, regs->reg0);
tm->tm_hour = FIELD_GET(TOY_HOUR, regs->reg0);
tm->tm_mday = FIELD_GET(TOY_DAY, regs->reg0);
tm->tm_mon = FIELD_GET(TOY_MON, regs->reg0) - 1;
}
static inline void ls2x_rtc_time_to_regs(struct rtc_time *tm,
struct ls2x_rtc_regs *regs)
{
regs->reg0 = FIELD_PREP(TOY_SEC, tm->tm_sec);
regs->reg0 |= FIELD_PREP(TOY_MIN, tm->tm_min);
regs->reg0 |= FIELD_PREP(TOY_HOUR, tm->tm_hour);
regs->reg0 |= FIELD_PREP(TOY_DAY, tm->tm_mday);
regs->reg0 |= FIELD_PREP(TOY_MON, tm->tm_mon + 1);
regs->reg1 = tm->tm_year;
}
static inline void ls2x_rtc_alarm_regs_to_time(struct ls2x_rtc_regs *regs,
struct rtc_time *tm)
{
tm->tm_sec = FIELD_GET(TOY_MATCH_SEC, regs->reg0);
tm->tm_min = FIELD_GET(TOY_MATCH_MIN, regs->reg0);
tm->tm_hour = FIELD_GET(TOY_MATCH_HOUR, regs->reg0);
tm->tm_mday = FIELD_GET(TOY_MATCH_DAY, regs->reg0);
tm->tm_mon = FIELD_GET(TOY_MATCH_MON, regs->reg0) - 1;
/*
* The rtc SYS_TOYMATCH0/YEAR bit field is only 6 bits,
* so it means 63 years at most. Therefore, The RTC alarm
* years can be set from 1900 to 1963.
* This causes the initialization of alarm fail during
* call __rtc_read_alarm. We add 64 years offset to
* ls2x_rtc_read_alarm. After adding the offset,
* the RTC alarm clock can be set from 1964 to 2027.
*/
tm->tm_year = FIELD_GET(TOY_MATCH_YEAR, regs->reg0) + 64;
}
static inline void ls2x_rtc_time_to_alarm_regs(struct rtc_time *tm,
struct ls2x_rtc_regs *regs)
{
regs->reg0 = FIELD_PREP(TOY_MATCH_SEC, tm->tm_sec);
regs->reg0 |= FIELD_PREP(TOY_MATCH_MIN, tm->tm_min);
regs->reg0 |= FIELD_PREP(TOY_MATCH_HOUR, tm->tm_hour);
regs->reg0 |= FIELD_PREP(TOY_MATCH_DAY, tm->tm_mday);
regs->reg0 |= FIELD_PREP(TOY_MATCH_MON, tm->tm_mon + 1);
regs->reg0 |= FIELD_PREP(TOY_MATCH_YEAR, tm->tm_year);
}
static int ls2x_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
int ret;
struct ls2x_rtc_regs regs;
struct ls2x_rtc_priv *priv = dev_get_drvdata(dev);
ret = regmap_read(priv->regmap, TOY_READ1_REG, &regs.reg1);
if (unlikely(ret))
return ret;
ret = regmap_read(priv->regmap, TOY_READ0_REG, &regs.reg0);
if (unlikely(ret))
return ret;
ls2x_rtc_regs_to_time(&regs, tm);
return 0;
}
static int ls2x_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
int ret;
struct ls2x_rtc_regs regs;
struct ls2x_rtc_priv *priv = dev_get_drvdata(dev);
ls2x_rtc_time_to_regs(tm, &regs);
ret = regmap_write(priv->regmap, TOY_WRITE0_REG, regs.reg0);
if (unlikely(ret))
return ret;
return regmap_write(priv->regmap, TOY_WRITE1_REG, regs.reg1);
}
static int ls2x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
int ret;
struct ls2x_rtc_regs regs;
struct ls2x_rtc_priv *priv = dev_get_drvdata(dev);
ret = regmap_read(priv->regmap, TOY_MATCH0_REG, &regs.reg0);
if (unlikely(ret))
return ret;
ls2x_rtc_alarm_regs_to_time(&regs, &alrm->time);
#if defined(CONFIG_ACPI)
ret = readl(priv->acpi_base + ACPI_PM1_EN_REG);
alrm->enabled = !!(ret & RTC_EN);
#endif
return 0;
}
static int ls2x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct ls2x_rtc_regs regs;
struct ls2x_rtc_priv *priv = dev_get_drvdata(dev);
ls2x_rtc_time_to_alarm_regs(&alrm->time, &regs);
return regmap_write(priv->regmap, TOY_MATCH0_REG, regs.reg0);
}
static struct rtc_class_ops ls2x_rtc_ops = {
.read_time = ls2x_rtc_read_time,
.set_time = ls2x_rtc_set_time,
.read_alarm = ls2x_rtc_read_alarm,
.set_alarm = ls2x_rtc_set_alarm,
};
static int ls2x_rtc_probe(struct platform_device *pdev)
{
int ret;
void __iomem *regs;
struct ls2x_rtc_priv *priv;
struct device *dev = &pdev->dev;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (unlikely(!priv))
return -ENOMEM;
spin_lock_init(&priv->rtc_reglock);
platform_set_drvdata(pdev, priv);
regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(regs))
return PTR_ERR(regs);
priv->regmap = devm_regmap_init_mmio(dev, regs,
&ls2x_rtc_regmap_config);
if (IS_ERR(priv->regmap))
return PTR_ERR(priv->regmap);
priv->rtcdev = devm_rtc_allocate_device(dev);
if (IS_ERR(priv->rtcdev))
return PTR_ERR(priv->rtcdev);
/* Due to hardware erratum, all years multiple of 4 are considered
* leap year, so only years 2000 through 2099 are usable.
*
* Previous out-of-tree versions of this driver wrote tm_year directly
* into the year register, so epoch 2000 must be used to preserve
* semantics on shipped systems.
*/
priv->rtcdev->range_min = RTC_TIMESTAMP_BEGIN_2000;
priv->rtcdev->range_max = RTC_TIMESTAMP_END_2099;
priv->rtcdev->ops = &ls2x_rtc_ops;
#ifdef CONFIG_ACPI
priv->acpi_base = regs - ACPI_RTC_OFFSET;
acpi_install_fixed_event_handler(ACPI_EVENT_RTC,
ls2x_acpi_fix_handler, priv);
#endif
if (!device_can_wakeup(&pdev->dev))
device_init_wakeup(dev, 1);
ret = rtc_register_device(priv->rtcdev);
if (unlikely(ret))
return ret;
/* An offset of -0.9s will call RTC set for wall clock time 10.0 s at 10.9 s */
priv->rtcdev->set_offset_nsec = -900000000;
/* If not cause hwclock huang */
priv->rtcdev->uie_unsupported = 1;
return ret;
}
#ifdef CONFIG_OF
static const struct of_device_id ls2x_rtc_of_match[] = {
{ .compatible = "loongson,ls2x-rtc" },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, ls2x_rtc_of_match);
#endif
#ifdef CONFIG_ACPI
static const struct acpi_device_id ls2x_rtc_acpi_match[] = {
{"LOON0001"},
{}
};
MODULE_DEVICE_TABLE(acpi, ls2x_rtc_acpi_match);
#endif
static struct platform_driver ls2x_rtc_driver = {
.probe = ls2x_rtc_probe,
.driver = {
.name = "ls2x-rtc",
.of_match_table = of_match_ptr(ls2x_rtc_of_match),
.acpi_match_table = ACPI_PTR(ls2x_rtc_acpi_match),
},
};
module_platform_driver(ls2x_rtc_driver);
MODULE_DESCRIPTION("LS2X RTC driver");
MODULE_AUTHOR("WANG Xuerui");
MODULE_AUTHOR("Huacai Chen");
MODULE_AUTHOR("Binbin Zhou");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:ls2x-rtc");