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WSL2-Linux-Kernel/drivers/watchdog/s3c2410_wdt.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) 2004 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
*
* S3C2410 Watchdog Timer Support
*
* Based on, softdog.c by Alan Cox,
* (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/timer.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <linux/cpufreq.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <linux/delay.h>
#define S3C2410_WTCON 0x00
#define S3C2410_WTDAT 0x04
#define S3C2410_WTCNT 0x08
#define S3C2410_WTCLRINT 0x0c
#define S3C2410_WTCNT_MAXCNT 0xffff
#define S3C2410_WTCON_RSTEN (1 << 0)
#define S3C2410_WTCON_INTEN (1 << 2)
#define S3C2410_WTCON_ENABLE (1 << 5)
#define S3C2410_WTCON_DIV16 (0 << 3)
#define S3C2410_WTCON_DIV32 (1 << 3)
#define S3C2410_WTCON_DIV64 (2 << 3)
#define S3C2410_WTCON_DIV128 (3 << 3)
#define S3C2410_WTCON_MAXDIV 0x80
#define S3C2410_WTCON_PRESCALE(x) ((x) << 8)
#define S3C2410_WTCON_PRESCALE_MASK (0xff << 8)
#define S3C2410_WTCON_PRESCALE_MAX 0xff
#define S3C2410_WATCHDOG_ATBOOT (0)
#define S3C2410_WATCHDOG_DEFAULT_TIME (15)
#define EXYNOS5_RST_STAT_REG_OFFSET 0x0404
#define EXYNOS5_WDT_DISABLE_REG_OFFSET 0x0408
#define EXYNOS5_WDT_MASK_RESET_REG_OFFSET 0x040c
#define EXYNOS850_CLUSTER0_NONCPU_OUT 0x1220
#define EXYNOS850_CLUSTER0_NONCPU_INT_EN 0x1244
#define EXYNOS850_CLUSTER1_NONCPU_OUT 0x1620
#define EXYNOS850_CLUSTER1_NONCPU_INT_EN 0x1644
#define EXYNOSAUTOV9_CLUSTER1_NONCPU_OUT 0x1520
#define EXYNOSAUTOV9_CLUSTER1_NONCPU_INT_EN 0x1544
#define EXYNOS850_CLUSTER0_WDTRESET_BIT 24
#define EXYNOS850_CLUSTER1_WDTRESET_BIT 23
#define EXYNOSAUTOV9_CLUSTER0_WDTRESET_BIT 25
#define EXYNOSAUTOV9_CLUSTER1_WDTRESET_BIT 24
/**
* DOC: Quirk flags for different Samsung watchdog IP-cores
*
* This driver supports multiple Samsung SoCs, each of which might have
* different set of registers and features supported. As watchdog block
* sometimes requires modifying PMU registers for proper functioning, register
* differences in both watchdog and PMU IP-cores should be accounted for. Quirk
* flags described below serve the purpose of telling the driver about mentioned
* SoC traits, and can be specified in driver data for each particular supported
* device.
*
* %QUIRK_HAS_WTCLRINT_REG: Watchdog block has WTCLRINT register. It's used to
* clear the interrupt once the interrupt service routine is complete. It's
* write-only, writing any values to this register clears the interrupt, but
* reading is not permitted.
*
* %QUIRK_HAS_PMU_MASK_RESET: PMU block has the register for disabling/enabling
* WDT reset request. On old SoCs it's usually called MASK_WDT_RESET_REQUEST,
* new SoCs have CLUSTERx_NONCPU_INT_EN register, which 'mask_bit' value is
* inverted compared to the former one.
*
* %QUIRK_HAS_PMU_RST_STAT: PMU block has RST_STAT (reset status) register,
* which contains bits indicating the reason for most recent CPU reset. If
* present, driver will use this register to check if previous reboot was due to
* watchdog timer reset.
*
* %QUIRK_HAS_PMU_AUTO_DISABLE: PMU block has AUTOMATIC_WDT_RESET_DISABLE
* register. If 'mask_bit' bit is set, PMU will disable WDT reset when
* corresponding processor is in reset state.
*
* %QUIRK_HAS_PMU_CNT_EN: PMU block has some register (e.g. CLUSTERx_NONCPU_OUT)
* with "watchdog counter enable" bit. That bit should be set to make watchdog
* counter running.
*/
#define QUIRK_HAS_WTCLRINT_REG (1 << 0)
#define QUIRK_HAS_PMU_MASK_RESET (1 << 1)
#define QUIRK_HAS_PMU_RST_STAT (1 << 2)
#define QUIRK_HAS_PMU_AUTO_DISABLE (1 << 3)
#define QUIRK_HAS_PMU_CNT_EN (1 << 4)
/* These quirks require that we have a PMU register map */
#define QUIRKS_HAVE_PMUREG \
(QUIRK_HAS_PMU_MASK_RESET | QUIRK_HAS_PMU_RST_STAT | \
QUIRK_HAS_PMU_AUTO_DISABLE | QUIRK_HAS_PMU_CNT_EN)
static bool nowayout = WATCHDOG_NOWAYOUT;
static int tmr_margin;
static int tmr_atboot = S3C2410_WATCHDOG_ATBOOT;
static int soft_noboot;
module_param(tmr_margin, int, 0);
module_param(tmr_atboot, int, 0);
module_param(nowayout, bool, 0);
module_param(soft_noboot, int, 0);
MODULE_PARM_DESC(tmr_margin, "Watchdog tmr_margin in seconds. (default="
__MODULE_STRING(S3C2410_WATCHDOG_DEFAULT_TIME) ")");
MODULE_PARM_DESC(tmr_atboot,
"Watchdog is started at boot time if set to 1, default="
__MODULE_STRING(S3C2410_WATCHDOG_ATBOOT));
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
MODULE_PARM_DESC(soft_noboot, "Watchdog action, set to 1 to ignore reboots, 0 to reboot (default 0)");
/**
* struct s3c2410_wdt_variant - Per-variant config data
*
* @disable_reg: Offset in pmureg for the register that disables the watchdog
* timer reset functionality.
* @mask_reset_reg: Offset in pmureg for the register that masks the watchdog
* timer reset functionality.
* @mask_reset_inv: If set, mask_reset_reg value will have inverted meaning.
* @mask_bit: Bit number for the watchdog timer in the disable register and the
* mask reset register.
* @rst_stat_reg: Offset in pmureg for the register that has the reset status.
* @rst_stat_bit: Bit number in the rst_stat register indicating a watchdog
* reset.
* @cnt_en_reg: Offset in pmureg for the register that enables WDT counter.
* @cnt_en_bit: Bit number for "watchdog counter enable" in cnt_en register.
* @quirks: A bitfield of quirks.
*/
struct s3c2410_wdt_variant {
int disable_reg;
int mask_reset_reg;
bool mask_reset_inv;
int mask_bit;
int rst_stat_reg;
int rst_stat_bit;
int cnt_en_reg;
int cnt_en_bit;
u32 quirks;
};
struct s3c2410_wdt {
struct device *dev;
struct clk *bus_clk; /* for register interface (PCLK) */
struct clk *src_clk; /* for WDT counter */
void __iomem *reg_base;
unsigned int count;
spinlock_t lock;
unsigned long wtcon_save;
unsigned long wtdat_save;
struct watchdog_device wdt_device;
struct notifier_block freq_transition;
const struct s3c2410_wdt_variant *drv_data;
struct regmap *pmureg;
};
static const struct s3c2410_wdt_variant drv_data_s3c2410 = {
.quirks = 0
};
#ifdef CONFIG_OF
static const struct s3c2410_wdt_variant drv_data_s3c6410 = {
.quirks = QUIRK_HAS_WTCLRINT_REG,
};
static const struct s3c2410_wdt_variant drv_data_exynos5250 = {
.disable_reg = EXYNOS5_WDT_DISABLE_REG_OFFSET,
.mask_reset_reg = EXYNOS5_WDT_MASK_RESET_REG_OFFSET,
.mask_bit = 20,
.rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
.rst_stat_bit = 20,
.quirks = QUIRK_HAS_WTCLRINT_REG | QUIRK_HAS_PMU_MASK_RESET | \
QUIRK_HAS_PMU_RST_STAT | QUIRK_HAS_PMU_AUTO_DISABLE,
};
static const struct s3c2410_wdt_variant drv_data_exynos5420 = {
.disable_reg = EXYNOS5_WDT_DISABLE_REG_OFFSET,
.mask_reset_reg = EXYNOS5_WDT_MASK_RESET_REG_OFFSET,
.mask_bit = 0,
.rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
.rst_stat_bit = 9,
.quirks = QUIRK_HAS_WTCLRINT_REG | QUIRK_HAS_PMU_MASK_RESET | \
QUIRK_HAS_PMU_RST_STAT | QUIRK_HAS_PMU_AUTO_DISABLE,
};
static const struct s3c2410_wdt_variant drv_data_exynos7 = {
.disable_reg = EXYNOS5_WDT_DISABLE_REG_OFFSET,
.mask_reset_reg = EXYNOS5_WDT_MASK_RESET_REG_OFFSET,
.mask_bit = 23,
.rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
.rst_stat_bit = 23, /* A57 WDTRESET */
.quirks = QUIRK_HAS_WTCLRINT_REG | QUIRK_HAS_PMU_MASK_RESET | \
QUIRK_HAS_PMU_RST_STAT | QUIRK_HAS_PMU_AUTO_DISABLE,
};
static const struct s3c2410_wdt_variant drv_data_exynos850_cl0 = {
.mask_reset_reg = EXYNOS850_CLUSTER0_NONCPU_INT_EN,
.mask_bit = 2,
.mask_reset_inv = true,
.rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
.rst_stat_bit = EXYNOS850_CLUSTER0_WDTRESET_BIT,
.cnt_en_reg = EXYNOS850_CLUSTER0_NONCPU_OUT,
.cnt_en_bit = 7,
.quirks = QUIRK_HAS_WTCLRINT_REG | QUIRK_HAS_PMU_MASK_RESET | \
QUIRK_HAS_PMU_RST_STAT | QUIRK_HAS_PMU_CNT_EN,
};
static const struct s3c2410_wdt_variant drv_data_exynos850_cl1 = {
.mask_reset_reg = EXYNOS850_CLUSTER1_NONCPU_INT_EN,
.mask_bit = 2,
.mask_reset_inv = true,
.rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
.rst_stat_bit = EXYNOS850_CLUSTER1_WDTRESET_BIT,
.cnt_en_reg = EXYNOS850_CLUSTER1_NONCPU_OUT,
.cnt_en_bit = 7,
.quirks = QUIRK_HAS_WTCLRINT_REG | QUIRK_HAS_PMU_MASK_RESET | \
QUIRK_HAS_PMU_RST_STAT | QUIRK_HAS_PMU_CNT_EN,
};
static const struct s3c2410_wdt_variant drv_data_exynosautov9_cl0 = {
.mask_reset_reg = EXYNOS850_CLUSTER0_NONCPU_INT_EN,
.mask_bit = 2,
.mask_reset_inv = true,
.rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
.rst_stat_bit = EXYNOSAUTOV9_CLUSTER0_WDTRESET_BIT,
.cnt_en_reg = EXYNOS850_CLUSTER0_NONCPU_OUT,
.cnt_en_bit = 7,
.quirks = QUIRK_HAS_WTCLRINT_REG | QUIRK_HAS_PMU_MASK_RESET |
QUIRK_HAS_PMU_RST_STAT | QUIRK_HAS_PMU_CNT_EN,
};
static const struct s3c2410_wdt_variant drv_data_exynosautov9_cl1 = {
.mask_reset_reg = EXYNOSAUTOV9_CLUSTER1_NONCPU_INT_EN,
.mask_bit = 2,
.mask_reset_inv = true,
.rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
.rst_stat_bit = EXYNOSAUTOV9_CLUSTER1_WDTRESET_BIT,
.cnt_en_reg = EXYNOSAUTOV9_CLUSTER1_NONCPU_OUT,
.cnt_en_bit = 7,
.quirks = QUIRK_HAS_WTCLRINT_REG | QUIRK_HAS_PMU_MASK_RESET |
QUIRK_HAS_PMU_RST_STAT | QUIRK_HAS_PMU_CNT_EN,
};
static const struct of_device_id s3c2410_wdt_match[] = {
{ .compatible = "samsung,s3c2410-wdt",
.data = &drv_data_s3c2410 },
{ .compatible = "samsung,s3c6410-wdt",
.data = &drv_data_s3c6410 },
{ .compatible = "samsung,exynos5250-wdt",
.data = &drv_data_exynos5250 },
{ .compatible = "samsung,exynos5420-wdt",
.data = &drv_data_exynos5420 },
{ .compatible = "samsung,exynos7-wdt",
.data = &drv_data_exynos7 },
{ .compatible = "samsung,exynos850-wdt",
.data = &drv_data_exynos850_cl0 },
{ .compatible = "samsung,exynosautov9-wdt",
.data = &drv_data_exynosautov9_cl0 },
{},
};
MODULE_DEVICE_TABLE(of, s3c2410_wdt_match);
#endif
static const struct platform_device_id s3c2410_wdt_ids[] = {
{
.name = "s3c2410-wdt",
.driver_data = (unsigned long)&drv_data_s3c2410,
},
{}
};
MODULE_DEVICE_TABLE(platform, s3c2410_wdt_ids);
/* functions */
static inline unsigned long s3c2410wdt_get_freq(struct s3c2410_wdt *wdt)
{
return clk_get_rate(wdt->src_clk ? wdt->src_clk : wdt->bus_clk);
}
static inline unsigned int s3c2410wdt_max_timeout(struct s3c2410_wdt *wdt)
{
const unsigned long freq = s3c2410wdt_get_freq(wdt);
return S3C2410_WTCNT_MAXCNT / (freq / (S3C2410_WTCON_PRESCALE_MAX + 1)
/ S3C2410_WTCON_MAXDIV);
}
static inline struct s3c2410_wdt *freq_to_wdt(struct notifier_block *nb)
{
return container_of(nb, struct s3c2410_wdt, freq_transition);
}
static int s3c2410wdt_disable_wdt_reset(struct s3c2410_wdt *wdt, bool mask)
{
const u32 mask_val = BIT(wdt->drv_data->mask_bit);
const u32 val = mask ? mask_val : 0;
int ret;
ret = regmap_update_bits(wdt->pmureg, wdt->drv_data->disable_reg,
mask_val, val);
if (ret < 0)
dev_err(wdt->dev, "failed to update reg(%d)\n", ret);
return ret;
}
static int s3c2410wdt_mask_wdt_reset(struct s3c2410_wdt *wdt, bool mask)
{
const u32 mask_val = BIT(wdt->drv_data->mask_bit);
const bool val_inv = wdt->drv_data->mask_reset_inv;
const u32 val = (mask ^ val_inv) ? mask_val : 0;
int ret;
ret = regmap_update_bits(wdt->pmureg, wdt->drv_data->mask_reset_reg,
mask_val, val);
if (ret < 0)
dev_err(wdt->dev, "failed to update reg(%d)\n", ret);
return ret;
}
static int s3c2410wdt_enable_counter(struct s3c2410_wdt *wdt, bool en)
{
const u32 mask_val = BIT(wdt->drv_data->cnt_en_bit);
const u32 val = en ? mask_val : 0;
int ret;
ret = regmap_update_bits(wdt->pmureg, wdt->drv_data->cnt_en_reg,
mask_val, val);
if (ret < 0)
dev_err(wdt->dev, "failed to update reg(%d)\n", ret);
return ret;
}
static int s3c2410wdt_enable(struct s3c2410_wdt *wdt, bool en)
{
int ret;
if (wdt->drv_data->quirks & QUIRK_HAS_PMU_AUTO_DISABLE) {
ret = s3c2410wdt_disable_wdt_reset(wdt, !en);
if (ret < 0)
return ret;
}
if (wdt->drv_data->quirks & QUIRK_HAS_PMU_MASK_RESET) {
ret = s3c2410wdt_mask_wdt_reset(wdt, !en);
if (ret < 0)
return ret;
}
if (wdt->drv_data->quirks & QUIRK_HAS_PMU_CNT_EN) {
ret = s3c2410wdt_enable_counter(wdt, en);
if (ret < 0)
return ret;
}
return 0;
}
static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
{
struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
spin_lock(&wdt->lock);
writel(wdt->count, wdt->reg_base + S3C2410_WTCNT);
spin_unlock(&wdt->lock);
return 0;
}
static void __s3c2410wdt_stop(struct s3c2410_wdt *wdt)
{
unsigned long wtcon;
wtcon = readl(wdt->reg_base + S3C2410_WTCON);
wtcon &= ~(S3C2410_WTCON_ENABLE | S3C2410_WTCON_RSTEN);
writel(wtcon, wdt->reg_base + S3C2410_WTCON);
}
static int s3c2410wdt_stop(struct watchdog_device *wdd)
{
struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
spin_lock(&wdt->lock);
__s3c2410wdt_stop(wdt);
spin_unlock(&wdt->lock);
return 0;
}
static int s3c2410wdt_start(struct watchdog_device *wdd)
{
unsigned long wtcon;
struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
spin_lock(&wdt->lock);
__s3c2410wdt_stop(wdt);
wtcon = readl(wdt->reg_base + S3C2410_WTCON);
wtcon |= S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV128;
if (soft_noboot) {
wtcon |= S3C2410_WTCON_INTEN;
wtcon &= ~S3C2410_WTCON_RSTEN;
} else {
wtcon &= ~S3C2410_WTCON_INTEN;
wtcon |= S3C2410_WTCON_RSTEN;
}
dev_dbg(wdt->dev, "Starting watchdog: count=0x%08x, wtcon=%08lx\n",
wdt->count, wtcon);
writel(wdt->count, wdt->reg_base + S3C2410_WTDAT);
writel(wdt->count, wdt->reg_base + S3C2410_WTCNT);
writel(wtcon, wdt->reg_base + S3C2410_WTCON);
spin_unlock(&wdt->lock);
return 0;
}
static inline int s3c2410wdt_is_running(struct s3c2410_wdt *wdt)
{
return readl(wdt->reg_base + S3C2410_WTCON) & S3C2410_WTCON_ENABLE;
}
static int s3c2410wdt_set_heartbeat(struct watchdog_device *wdd,
unsigned int timeout)
{
struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
unsigned long freq = s3c2410wdt_get_freq(wdt);
unsigned int count;
unsigned int divisor = 1;
unsigned long wtcon;
if (timeout < 1)
return -EINVAL;
freq = DIV_ROUND_UP(freq, 128);
count = timeout * freq;
dev_dbg(wdt->dev, "Heartbeat: count=%d, timeout=%d, freq=%lu\n",
count, timeout, freq);
/* if the count is bigger than the watchdog register,
then work out what we need to do (and if) we can
actually make this value
*/
if (count >= 0x10000) {
divisor = DIV_ROUND_UP(count, 0xffff);
if (divisor > 0x100) {
dev_err(wdt->dev, "timeout %d too big\n", timeout);
return -EINVAL;
}
}
dev_dbg(wdt->dev, "Heartbeat: timeout=%d, divisor=%d, count=%d (%08x)\n",
timeout, divisor, count, DIV_ROUND_UP(count, divisor));
count = DIV_ROUND_UP(count, divisor);
wdt->count = count;
/* update the pre-scaler */
wtcon = readl(wdt->reg_base + S3C2410_WTCON);
wtcon &= ~S3C2410_WTCON_PRESCALE_MASK;
wtcon |= S3C2410_WTCON_PRESCALE(divisor-1);
writel(count, wdt->reg_base + S3C2410_WTDAT);
writel(wtcon, wdt->reg_base + S3C2410_WTCON);
wdd->timeout = (count * divisor) / freq;
return 0;
}
static int s3c2410wdt_restart(struct watchdog_device *wdd, unsigned long action,
void *data)
{
struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
void __iomem *wdt_base = wdt->reg_base;
/* disable watchdog, to be safe */
writel(0, wdt_base + S3C2410_WTCON);
/* put initial values into count and data */
writel(0x80, wdt_base + S3C2410_WTCNT);
writel(0x80, wdt_base + S3C2410_WTDAT);
/* set the watchdog to go and reset... */
writel(S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV16 |
S3C2410_WTCON_RSTEN | S3C2410_WTCON_PRESCALE(0x20),
wdt_base + S3C2410_WTCON);
/* wait for reset to assert... */
mdelay(500);
return 0;
}
#define OPTIONS (WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE)
static const struct watchdog_info s3c2410_wdt_ident = {
.options = OPTIONS,
.firmware_version = 0,
.identity = "S3C2410 Watchdog",
};
static const struct watchdog_ops s3c2410wdt_ops = {
.owner = THIS_MODULE,
.start = s3c2410wdt_start,
.stop = s3c2410wdt_stop,
.ping = s3c2410wdt_keepalive,
.set_timeout = s3c2410wdt_set_heartbeat,
.restart = s3c2410wdt_restart,
};
static const struct watchdog_device s3c2410_wdd = {
.info = &s3c2410_wdt_ident,
.ops = &s3c2410wdt_ops,
.timeout = S3C2410_WATCHDOG_DEFAULT_TIME,
};
/* interrupt handler code */
static irqreturn_t s3c2410wdt_irq(int irqno, void *param)
{
struct s3c2410_wdt *wdt = platform_get_drvdata(param);
dev_info(wdt->dev, "watchdog timer expired (irq)\n");
s3c2410wdt_keepalive(&wdt->wdt_device);
if (wdt->drv_data->quirks & QUIRK_HAS_WTCLRINT_REG)
writel(0x1, wdt->reg_base + S3C2410_WTCLRINT);
return IRQ_HANDLED;
}
#ifdef CONFIG_ARM_S3C24XX_CPUFREQ
static int s3c2410wdt_cpufreq_transition(struct notifier_block *nb,
unsigned long val, void *data)
{
int ret;
struct s3c2410_wdt *wdt = freq_to_wdt(nb);
if (!s3c2410wdt_is_running(wdt))
goto done;
if (val == CPUFREQ_PRECHANGE) {
/* To ensure that over the change we don't cause the
* watchdog to trigger, we perform an keep-alive if
* the watchdog is running.
*/
s3c2410wdt_keepalive(&wdt->wdt_device);
} else if (val == CPUFREQ_POSTCHANGE) {
s3c2410wdt_stop(&wdt->wdt_device);
ret = s3c2410wdt_set_heartbeat(&wdt->wdt_device,
wdt->wdt_device.timeout);
if (ret >= 0)
s3c2410wdt_start(&wdt->wdt_device);
else
goto err;
}
done:
return 0;
err:
dev_err(wdt->dev, "cannot set new value for timeout %d\n",
wdt->wdt_device.timeout);
return ret;
}
static inline int s3c2410wdt_cpufreq_register(struct s3c2410_wdt *wdt)
{
wdt->freq_transition.notifier_call = s3c2410wdt_cpufreq_transition;
return cpufreq_register_notifier(&wdt->freq_transition,
CPUFREQ_TRANSITION_NOTIFIER);
}
static inline void s3c2410wdt_cpufreq_deregister(struct s3c2410_wdt *wdt)
{
wdt->freq_transition.notifier_call = s3c2410wdt_cpufreq_transition;
cpufreq_unregister_notifier(&wdt->freq_transition,
CPUFREQ_TRANSITION_NOTIFIER);
}
#else
static inline int s3c2410wdt_cpufreq_register(struct s3c2410_wdt *wdt)
{
return 0;
}
static inline void s3c2410wdt_cpufreq_deregister(struct s3c2410_wdt *wdt)
{
}
#endif
static inline unsigned int s3c2410wdt_get_bootstatus(struct s3c2410_wdt *wdt)
{
unsigned int rst_stat;
int ret;
if (!(wdt->drv_data->quirks & QUIRK_HAS_PMU_RST_STAT))
return 0;
ret = regmap_read(wdt->pmureg, wdt->drv_data->rst_stat_reg, &rst_stat);
if (ret)
dev_warn(wdt->dev, "Couldn't get RST_STAT register\n");
else if (rst_stat & BIT(wdt->drv_data->rst_stat_bit))
return WDIOF_CARDRESET;
return 0;
}
static inline const struct s3c2410_wdt_variant *
s3c2410_get_wdt_drv_data(struct platform_device *pdev)
{
const struct s3c2410_wdt_variant *variant;
struct device *dev = &pdev->dev;
variant = of_device_get_match_data(dev);
if (!variant) {
/* Device matched by platform_device_id */
variant = (struct s3c2410_wdt_variant *)
platform_get_device_id(pdev)->driver_data;
}
#ifdef CONFIG_OF
/* Choose Exynos850/ExynosAutov9 driver data w.r.t. cluster index */
if (variant == &drv_data_exynos850_cl0 ||
variant == &drv_data_exynosautov9_cl0) {
u32 index;
int err;
err = of_property_read_u32(dev->of_node,
"samsung,cluster-index", &index);
if (err) {
dev_err(dev, "failed to get cluster index\n");
return NULL;
}
switch (index) {
case 0:
return variant;
case 1:
return (variant == &drv_data_exynos850_cl0) ?
&drv_data_exynos850_cl1 :
&drv_data_exynosautov9_cl1;
default:
dev_err(dev, "wrong cluster index: %u\n", index);
return NULL;
}
}
#endif
return variant;
}
static int s3c2410wdt_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct s3c2410_wdt *wdt;
unsigned int wtcon;
int wdt_irq;
int ret;
wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
if (!wdt)
return -ENOMEM;
wdt->dev = dev;
spin_lock_init(&wdt->lock);
wdt->wdt_device = s3c2410_wdd;
wdt->drv_data = s3c2410_get_wdt_drv_data(pdev);
if (!wdt->drv_data)
return -EINVAL;
if (wdt->drv_data->quirks & QUIRKS_HAVE_PMUREG) {
wdt->pmureg = syscon_regmap_lookup_by_phandle(dev->of_node,
"samsung,syscon-phandle");
if (IS_ERR(wdt->pmureg)) {
dev_err(dev, "syscon regmap lookup failed.\n");
return PTR_ERR(wdt->pmureg);
}
}
wdt_irq = platform_get_irq(pdev, 0);
if (wdt_irq < 0)
return wdt_irq;
/* get the memory region for the watchdog timer */
wdt->reg_base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(wdt->reg_base))
return PTR_ERR(wdt->reg_base);
wdt->bus_clk = devm_clk_get(dev, "watchdog");
if (IS_ERR(wdt->bus_clk)) {
dev_err(dev, "failed to find bus clock\n");
return PTR_ERR(wdt->bus_clk);
}
ret = clk_prepare_enable(wdt->bus_clk);
if (ret < 0) {
dev_err(dev, "failed to enable bus clock\n");
return ret;
}
/*
* "watchdog_src" clock is optional; if it's not present -- just skip it
* and use "watchdog" clock as both bus and source clock.
*/
wdt->src_clk = devm_clk_get_optional(dev, "watchdog_src");
if (IS_ERR(wdt->src_clk)) {
dev_err_probe(dev, PTR_ERR(wdt->src_clk),
"failed to get source clock\n");
ret = PTR_ERR(wdt->src_clk);
goto err_bus_clk;
}
ret = clk_prepare_enable(wdt->src_clk);
if (ret) {
dev_err(dev, "failed to enable source clock\n");
goto err_bus_clk;
}
wdt->wdt_device.min_timeout = 1;
wdt->wdt_device.max_timeout = s3c2410wdt_max_timeout(wdt);
ret = s3c2410wdt_cpufreq_register(wdt);
if (ret < 0) {
dev_err(dev, "failed to register cpufreq\n");
goto err_src_clk;
}
watchdog_set_drvdata(&wdt->wdt_device, wdt);
/* see if we can actually set the requested timer margin, and if
* not, try the default value */
watchdog_init_timeout(&wdt->wdt_device, tmr_margin, dev);
ret = s3c2410wdt_set_heartbeat(&wdt->wdt_device,
wdt->wdt_device.timeout);
if (ret) {
ret = s3c2410wdt_set_heartbeat(&wdt->wdt_device,
S3C2410_WATCHDOG_DEFAULT_TIME);
if (ret == 0) {
dev_warn(dev, "tmr_margin value out of range, default %d used\n",
S3C2410_WATCHDOG_DEFAULT_TIME);
} else {
dev_err(dev, "failed to use default timeout\n");
goto err_cpufreq;
}
}
ret = devm_request_irq(dev, wdt_irq, s3c2410wdt_irq, 0,
pdev->name, pdev);
if (ret != 0) {
dev_err(dev, "failed to install irq (%d)\n", ret);
goto err_cpufreq;
}
watchdog_set_nowayout(&wdt->wdt_device, nowayout);
watchdog_set_restart_priority(&wdt->wdt_device, 128);
wdt->wdt_device.bootstatus = s3c2410wdt_get_bootstatus(wdt);
wdt->wdt_device.parent = dev;
/*
* If "tmr_atboot" param is non-zero, start the watchdog right now. Also
* set WDOG_HW_RUNNING bit, so that watchdog core can kick the watchdog.
*
* If we're not enabling the watchdog, then ensure it is disabled if it
* has been left running from the bootloader or other source.
*/
if (tmr_atboot) {
dev_info(dev, "starting watchdog timer\n");
s3c2410wdt_start(&wdt->wdt_device);
set_bit(WDOG_HW_RUNNING, &wdt->wdt_device.status);
} else {
s3c2410wdt_stop(&wdt->wdt_device);
}
ret = watchdog_register_device(&wdt->wdt_device);
if (ret)
goto err_cpufreq;
ret = s3c2410wdt_enable(wdt, true);
if (ret < 0)
goto err_unregister;
platform_set_drvdata(pdev, wdt);
/* print out a statement of readiness */
wtcon = readl(wdt->reg_base + S3C2410_WTCON);
dev_info(dev, "watchdog %sactive, reset %sabled, irq %sabled\n",
(wtcon & S3C2410_WTCON_ENABLE) ? "" : "in",
(wtcon & S3C2410_WTCON_RSTEN) ? "en" : "dis",
(wtcon & S3C2410_WTCON_INTEN) ? "en" : "dis");
return 0;
err_unregister:
watchdog_unregister_device(&wdt->wdt_device);
err_cpufreq:
s3c2410wdt_cpufreq_deregister(wdt);
err_src_clk:
clk_disable_unprepare(wdt->src_clk);
err_bus_clk:
clk_disable_unprepare(wdt->bus_clk);
return ret;
}
static int s3c2410wdt_remove(struct platform_device *dev)
{
int ret;
struct s3c2410_wdt *wdt = platform_get_drvdata(dev);
ret = s3c2410wdt_enable(wdt, false);
if (ret < 0)
return ret;
watchdog_unregister_device(&wdt->wdt_device);
s3c2410wdt_cpufreq_deregister(wdt);
clk_disable_unprepare(wdt->src_clk);
clk_disable_unprepare(wdt->bus_clk);
return 0;
}
static void s3c2410wdt_shutdown(struct platform_device *dev)
{
struct s3c2410_wdt *wdt = platform_get_drvdata(dev);
s3c2410wdt_enable(wdt, false);
s3c2410wdt_stop(&wdt->wdt_device);
}
static int s3c2410wdt_suspend(struct device *dev)
{
int ret;
struct s3c2410_wdt *wdt = dev_get_drvdata(dev);
/* Save watchdog state, and turn it off. */
wdt->wtcon_save = readl(wdt->reg_base + S3C2410_WTCON);
wdt->wtdat_save = readl(wdt->reg_base + S3C2410_WTDAT);
ret = s3c2410wdt_enable(wdt, false);
if (ret < 0)
return ret;
/* Note that WTCNT doesn't need to be saved. */
s3c2410wdt_stop(&wdt->wdt_device);
return 0;
}
static int s3c2410wdt_resume(struct device *dev)
{
int ret;
struct s3c2410_wdt *wdt = dev_get_drvdata(dev);
/* Restore watchdog state. */
writel(wdt->wtdat_save, wdt->reg_base + S3C2410_WTDAT);
writel(wdt->wtdat_save, wdt->reg_base + S3C2410_WTCNT);/* Reset count */
writel(wdt->wtcon_save, wdt->reg_base + S3C2410_WTCON);
ret = s3c2410wdt_enable(wdt, true);
if (ret < 0)
return ret;
dev_info(dev, "watchdog %sabled\n",
(wdt->wtcon_save & S3C2410_WTCON_ENABLE) ? "en" : "dis");
return 0;
}
static DEFINE_SIMPLE_DEV_PM_OPS(s3c2410wdt_pm_ops,
s3c2410wdt_suspend, s3c2410wdt_resume);
static struct platform_driver s3c2410wdt_driver = {
.probe = s3c2410wdt_probe,
.remove = s3c2410wdt_remove,
.shutdown = s3c2410wdt_shutdown,
.id_table = s3c2410_wdt_ids,
.driver = {
.name = "s3c2410-wdt",
.pm = pm_sleep_ptr(&s3c2410wdt_pm_ops),
.of_match_table = of_match_ptr(s3c2410_wdt_match),
},
};
module_platform_driver(s3c2410wdt_driver);
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>, Dimitry Andric <dimitry.andric@tomtom.com>");
MODULE_DESCRIPTION("S3C2410 Watchdog Device Driver");
MODULE_LICENSE("GPL");
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