forked from Minki/linux
watchdog: add Alphascale asm9260-wdt driver
Add WD support for Alphascale asm9260 SoC. This driver provide support for different function modes: - HW mode to trigger SoC reset on timeout - SW mode do soft reset if needed - DEBUG mode Signed-off-by: Oleksij Rempel <linux@rempel-privat.de> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This commit is contained in:
Oleksij Rempel
Wim Van Sebroeck
parent
bf90063999
commit
aae03dc981
@ -180,6 +180,16 @@ config ARM_SP805_WATCHDOG
|
||||
ARM Primecell SP805 Watchdog timer. This will reboot your system when
|
||||
the timeout is reached.
|
||||
|
||||
config ASM9260_WATCHDOG
|
||||
tristate "Alphascale ASM9260 watchdog"
|
||||
depends on MACH_ASM9260
|
||||
depends on OF
|
||||
select WATCHDOG_CORE
|
||||
select RESET_CONTROLLER
|
||||
help
|
||||
Watchdog timer embedded into Alphascale asm9260 chips. This will reboot your
|
||||
system when the timeout is reached.
|
||||
|
||||
config AT91RM9200_WATCHDOG
|
||||
tristate "AT91RM9200 watchdog"
|
||||
depends on SOC_AT91RM9200 && MFD_SYSCON
|
||||
|
||||
@ -30,6 +30,7 @@ obj-$(CONFIG_USBPCWATCHDOG) += pcwd_usb.o
|
||||
|
||||
# ARM Architecture
|
||||
obj-$(CONFIG_ARM_SP805_WATCHDOG) += sp805_wdt.o
|
||||
obj-$(CONFIG_ASM9260_WATCHDOG) += asm9260_wdt.o
|
||||
obj-$(CONFIG_AT91RM9200_WATCHDOG) += at91rm9200_wdt.o
|
||||
obj-$(CONFIG_AT91SAM9X_WATCHDOG) += at91sam9_wdt.o
|
||||
obj-$(CONFIG_CADENCE_WATCHDOG) += cadence_wdt.o
|
||||
|
||||
403
drivers/watchdog/asm9260_wdt.c
Normal file
403
drivers/watchdog/asm9260_wdt.c
Normal file
@ -0,0 +1,403 @@
|
||||
/*
|
||||
* Watchdog driver for Alphascale ASM9260.
|
||||
*
|
||||
* Copyright (c) 2014 Oleksij Rempel <linux@rempel-privat.de>
|
||||
*
|
||||
* Licensed under GPLv2 or later.
|
||||
*/
|
||||
|
||||
#include <linux/bitops.h>
|
||||
#include <linux/clk.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/interrupt.h>
|
||||
#include <linux/io.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/of.h>
|
||||
#include <linux/platform_device.h>
|
||||
#include <linux/reboot.h>
|
||||
#include <linux/reset.h>
|
||||
#include <linux/watchdog.h>
|
||||
|
||||
#define CLOCK_FREQ 1000000
|
||||
|
||||
/* Watchdog Mode register */
|
||||
#define HW_WDMOD 0x00
|
||||
/* Wake interrupt. Set by HW, can't be cleared. */
|
||||
#define BM_MOD_WDINT BIT(3)
|
||||
/* This bit set if timeout reached. Cleared by SW. */
|
||||
#define BM_MOD_WDTOF BIT(2)
|
||||
/* HW Reset on timeout */
|
||||
#define BM_MOD_WDRESET BIT(1)
|
||||
/* WD enable */
|
||||
#define BM_MOD_WDEN BIT(0)
|
||||
|
||||
/*
|
||||
* Watchdog Timer Constant register
|
||||
* Minimal value is 0xff, the meaning of this value
|
||||
* depends on used clock: T = WDCLK * (0xff + 1) * 4
|
||||
*/
|
||||
#define HW_WDTC 0x04
|
||||
#define BM_WDTC_MAX(freq) (0x7fffffff / (freq))
|
||||
|
||||
/* Watchdog Feed register */
|
||||
#define HW_WDFEED 0x08
|
||||
|
||||
/* Watchdog Timer Value register */
|
||||
#define HW_WDTV 0x0c
|
||||
|
||||
#define ASM9260_WDT_DEFAULT_TIMEOUT 30
|
||||
|
||||
enum asm9260_wdt_mode {
|
||||
HW_RESET,
|
||||
SW_RESET,
|
||||
DEBUG,
|
||||
};
|
||||
|
||||
struct asm9260_wdt_priv {
|
||||
struct device *dev;
|
||||
struct watchdog_device wdd;
|
||||
struct clk *clk;
|
||||
struct clk *clk_ahb;
|
||||
struct reset_control *rst;
|
||||
struct notifier_block restart_handler;
|
||||
|
||||
void __iomem *iobase;
|
||||
int irq;
|
||||
unsigned long wdt_freq;
|
||||
enum asm9260_wdt_mode mode;
|
||||
};
|
||||
|
||||
static int asm9260_wdt_feed(struct watchdog_device *wdd)
|
||||
{
|
||||
struct asm9260_wdt_priv *priv = watchdog_get_drvdata(wdd);
|
||||
|
||||
iowrite32(0xaa, priv->iobase + HW_WDFEED);
|
||||
iowrite32(0x55, priv->iobase + HW_WDFEED);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static unsigned int asm9260_wdt_gettimeleft(struct watchdog_device *wdd)
|
||||
{
|
||||
struct asm9260_wdt_priv *priv = watchdog_get_drvdata(wdd);
|
||||
u32 counter;
|
||||
|
||||
counter = ioread32(priv->iobase + HW_WDTV);
|
||||
|
||||
return DIV_ROUND_CLOSEST(counter, priv->wdt_freq);
|
||||
}
|
||||
|
||||
static int asm9260_wdt_updatetimeout(struct watchdog_device *wdd)
|
||||
{
|
||||
struct asm9260_wdt_priv *priv = watchdog_get_drvdata(wdd);
|
||||
u32 counter;
|
||||
|
||||
counter = wdd->timeout * priv->wdt_freq;
|
||||
|
||||
iowrite32(counter, priv->iobase + HW_WDTC);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int asm9260_wdt_enable(struct watchdog_device *wdd)
|
||||
{
|
||||
struct asm9260_wdt_priv *priv = watchdog_get_drvdata(wdd);
|
||||
u32 mode = 0;
|
||||
|
||||
if (priv->mode == HW_RESET)
|
||||
mode = BM_MOD_WDRESET;
|
||||
|
||||
iowrite32(BM_MOD_WDEN | mode, priv->iobase + HW_WDMOD);
|
||||
|
||||
asm9260_wdt_updatetimeout(wdd);
|
||||
|
||||
asm9260_wdt_feed(wdd);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int asm9260_wdt_disable(struct watchdog_device *wdd)
|
||||
{
|
||||
struct asm9260_wdt_priv *priv = watchdog_get_drvdata(wdd);
|
||||
|
||||
/* The only way to disable WD is to reset it. */
|
||||
reset_control_assert(priv->rst);
|
||||
reset_control_deassert(priv->rst);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int asm9260_wdt_settimeout(struct watchdog_device *wdd, unsigned int to)
|
||||
{
|
||||
wdd->timeout = to;
|
||||
asm9260_wdt_updatetimeout(wdd);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void asm9260_wdt_sys_reset(struct asm9260_wdt_priv *priv)
|
||||
{
|
||||
/* init WD if it was not started */
|
||||
|
||||
iowrite32(BM_MOD_WDEN | BM_MOD_WDRESET, priv->iobase + HW_WDMOD);
|
||||
|
||||
iowrite32(0xff, priv->iobase + HW_WDTC);
|
||||
/* first pass correct sequence */
|
||||
asm9260_wdt_feed(&priv->wdd);
|
||||
/*
|
||||
* Then write wrong pattern to the feed to trigger reset
|
||||
* ASAP.
|
||||
*/
|
||||
iowrite32(0xff, priv->iobase + HW_WDFEED);
|
||||
|
||||
mdelay(1000);
|
||||
}
|
||||
|
||||
static irqreturn_t asm9260_wdt_irq(int irq, void *devid)
|
||||
{
|
||||
struct asm9260_wdt_priv *priv = devid;
|
||||
u32 stat;
|
||||
|
||||
stat = ioread32(priv->iobase + HW_WDMOD);
|
||||
if (!(stat & BM_MOD_WDINT))
|
||||
return IRQ_NONE;
|
||||
|
||||
if (priv->mode == DEBUG) {
|
||||
dev_info(priv->dev, "Watchdog Timeout. Do nothing.\n");
|
||||
} else {
|
||||
dev_info(priv->dev, "Watchdog Timeout. Doing SW Reset.\n");
|
||||
asm9260_wdt_sys_reset(priv);
|
||||
}
|
||||
|
||||
return IRQ_HANDLED;
|
||||
}
|
||||
|
||||
static int asm9260_restart_handler(struct notifier_block *this,
|
||||
unsigned long mode, void *cmd)
|
||||
{
|
||||
struct asm9260_wdt_priv *priv =
|
||||
container_of(this, struct asm9260_wdt_priv, restart_handler);
|
||||
|
||||
asm9260_wdt_sys_reset(priv);
|
||||
|
||||
return NOTIFY_DONE;
|
||||
}
|
||||
|
||||
static const struct watchdog_info asm9260_wdt_ident = {
|
||||
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING
|
||||
| WDIOF_MAGICCLOSE,
|
||||
.identity = "Alphascale asm9260 Watchdog",
|
||||
};
|
||||
|
||||
static struct watchdog_ops asm9260_wdt_ops = {
|
||||
.owner = THIS_MODULE,
|
||||
.start = asm9260_wdt_enable,
|
||||
.stop = asm9260_wdt_disable,
|
||||
.get_timeleft = asm9260_wdt_gettimeleft,
|
||||
.ping = asm9260_wdt_feed,
|
||||
.set_timeout = asm9260_wdt_settimeout,
|
||||
};
|
||||
|
||||
static int __init asm9260_wdt_get_dt_clks(struct asm9260_wdt_priv *priv)
|
||||
{
|
||||
int err;
|
||||
unsigned long clk;
|
||||
|
||||
priv->clk = devm_clk_get(priv->dev, "mod");
|
||||
if (IS_ERR(priv->clk)) {
|
||||
dev_err(priv->dev, "Failed to get \"mod\" clk\n");
|
||||
return PTR_ERR(priv->clk);
|
||||
}
|
||||
|
||||
/* configure AHB clock */
|
||||
priv->clk_ahb = devm_clk_get(priv->dev, "ahb");
|
||||
if (IS_ERR(priv->clk_ahb)) {
|
||||
dev_err(priv->dev, "Failed to get \"ahb\" clk\n");
|
||||
return PTR_ERR(priv->clk_ahb);
|
||||
}
|
||||
|
||||
err = clk_prepare_enable(priv->clk_ahb);
|
||||
if (err) {
|
||||
dev_err(priv->dev, "Failed to enable ahb_clk!\n");
|
||||
return err;
|
||||
}
|
||||
|
||||
err = clk_set_rate(priv->clk, CLOCK_FREQ);
|
||||
if (err) {
|
||||
clk_disable_unprepare(priv->clk_ahb);
|
||||
dev_err(priv->dev, "Failed to set rate!\n");
|
||||
return err;
|
||||
}
|
||||
|
||||
err = clk_prepare_enable(priv->clk);
|
||||
if (err) {
|
||||
clk_disable_unprepare(priv->clk_ahb);
|
||||
dev_err(priv->dev, "Failed to enable clk!\n");
|
||||
return err;
|
||||
}
|
||||
|
||||
/* wdt has internal divider */
|
||||
clk = clk_get_rate(priv->clk);
|
||||
if (!clk) {
|
||||
clk_disable_unprepare(priv->clk);
|
||||
clk_disable_unprepare(priv->clk_ahb);
|
||||
dev_err(priv->dev, "Failed, clk is 0!\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
priv->wdt_freq = clk / 2;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void __init asm9260_wdt_get_dt_mode(struct asm9260_wdt_priv *priv)
|
||||
{
|
||||
const char *tmp;
|
||||
int ret;
|
||||
|
||||
/* default mode */
|
||||
priv->mode = HW_RESET;
|
||||
|
||||
ret = of_property_read_string(priv->dev->of_node,
|
||||
"alphascale,mode", &tmp);
|
||||
if (ret < 0)
|
||||
return;
|
||||
|
||||
if (!strcmp(tmp, "hw"))
|
||||
priv->mode = HW_RESET;
|
||||
else if (!strcmp(tmp, "sw"))
|
||||
priv->mode = SW_RESET;
|
||||
else if (!strcmp(tmp, "debug"))
|
||||
priv->mode = DEBUG;
|
||||
else
|
||||
dev_warn(priv->dev, "unknown reset-type: %s. Using default \"hw\" mode.",
|
||||
tmp);
|
||||
}
|
||||
|
||||
static int __init asm9260_wdt_probe(struct platform_device *pdev)
|
||||
{
|
||||
struct asm9260_wdt_priv *priv;
|
||||
struct watchdog_device *wdd;
|
||||
struct resource *res;
|
||||
int ret;
|
||||
const char * const mode_name[] = { "hw", "sw", "debug", };
|
||||
|
||||
priv = devm_kzalloc(&pdev->dev, sizeof(struct asm9260_wdt_priv),
|
||||
GFP_KERNEL);
|
||||
if (!priv)
|
||||
return -ENOMEM;
|
||||
|
||||
priv->dev = &pdev->dev;
|
||||
|
||||
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
||||
priv->iobase = devm_ioremap_resource(&pdev->dev, res);
|
||||
if (IS_ERR(priv->iobase))
|
||||
return PTR_ERR(priv->iobase);
|
||||
|
||||
ret = asm9260_wdt_get_dt_clks(priv);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
priv->rst = devm_reset_control_get(&pdev->dev, "wdt_rst");
|
||||
if (IS_ERR(priv->rst))
|
||||
return PTR_ERR(priv->rst);
|
||||
|
||||
wdd = &priv->wdd;
|
||||
wdd->info = &asm9260_wdt_ident;
|
||||
wdd->ops = &asm9260_wdt_ops;
|
||||
wdd->min_timeout = 1;
|
||||
wdd->max_timeout = BM_WDTC_MAX(priv->wdt_freq);
|
||||
wdd->parent = &pdev->dev;
|
||||
|
||||
watchdog_set_drvdata(wdd, priv);
|
||||
|
||||
/*
|
||||
* If 'timeout-sec' unspecified in devicetree, assume a 30 second
|
||||
* default, unless the max timeout is less than 30 seconds, then use
|
||||
* the max instead.
|
||||
*/
|
||||
wdd->timeout = ASM9260_WDT_DEFAULT_TIMEOUT;
|
||||
watchdog_init_timeout(wdd, 0, &pdev->dev);
|
||||
|
||||
asm9260_wdt_get_dt_mode(priv);
|
||||
|
||||
if (priv->mode != HW_RESET)
|
||||
priv->irq = platform_get_irq(pdev, 0);
|
||||
|
||||
if (priv->irq > 0) {
|
||||
/*
|
||||
* Not all supported platforms specify an interrupt for the
|
||||
* watchdog, so let's make it optional.
|
||||
*/
|
||||
ret = devm_request_irq(&pdev->dev, priv->irq,
|
||||
asm9260_wdt_irq, 0, pdev->name, priv);
|
||||
if (ret < 0)
|
||||
dev_warn(&pdev->dev, "failed to request IRQ\n");
|
||||
}
|
||||
|
||||
ret = watchdog_register_device(wdd);
|
||||
if (ret)
|
||||
goto clk_off;
|
||||
|
||||
platform_set_drvdata(pdev, priv);
|
||||
|
||||
priv->restart_handler.notifier_call = asm9260_restart_handler;
|
||||
priv->restart_handler.priority = 128;
|
||||
ret = register_restart_handler(&priv->restart_handler);
|
||||
if (ret)
|
||||
dev_warn(&pdev->dev, "cannot register restart handler\n");
|
||||
|
||||
dev_info(&pdev->dev, "Watchdog enabled (timeout: %d sec, mode: %s)\n",
|
||||
wdd->timeout, mode_name[priv->mode]);
|
||||
return 0;
|
||||
|
||||
clk_off:
|
||||
clk_disable_unprepare(priv->clk);
|
||||
clk_disable_unprepare(priv->clk_ahb);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static void asm9260_wdt_shutdown(struct platform_device *pdev)
|
||||
{
|
||||
struct asm9260_wdt_priv *priv = platform_get_drvdata(pdev);
|
||||
|
||||
asm9260_wdt_disable(&priv->wdd);
|
||||
}
|
||||
|
||||
static int __exit asm9260_wdt_remove(struct platform_device *pdev)
|
||||
{
|
||||
struct asm9260_wdt_priv *priv = platform_get_drvdata(pdev);
|
||||
|
||||
asm9260_wdt_disable(&priv->wdd);
|
||||
|
||||
unregister_restart_handler(&priv->restart_handler);
|
||||
|
||||
watchdog_unregister_device(&priv->wdd);
|
||||
|
||||
clk_disable_unprepare(priv->clk);
|
||||
clk_disable_unprepare(priv->clk_ahb);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct of_device_id asm9260_wdt_of_match[] = {
|
||||
{ .compatible = "alphascale,asm9260-wdt"},
|
||||
{},
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, asm9260_wdt_of_match);
|
||||
|
||||
static struct platform_driver asm9260_wdt_driver = {
|
||||
.driver = {
|
||||
.name = "asm9260-wdt",
|
||||
.owner = THIS_MODULE,
|
||||
.of_match_table = asm9260_wdt_of_match,
|
||||
},
|
||||
.probe = asm9260_wdt_probe,
|
||||
.remove = asm9260_wdt_remove,
|
||||
.shutdown = asm9260_wdt_shutdown,
|
||||
};
|
||||
module_platform_driver(asm9260_wdt_driver);
|
||||
|
||||
MODULE_DESCRIPTION("asm9260 WatchDog Timer Driver");
|
||||
MODULE_AUTHOR("Oleksij Rempel <linux@rempel-privat.de>");
|
||||
MODULE_LICENSE("GPL");
|
||||
Loading…
Reference in New Issue
Block a user