267 строки
6.8 KiB
C
267 строки
6.8 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* mpc8xxx_wdt.c - MPC8xx/MPC83xx/MPC86xx watchdog userspace interface
|
|
*
|
|
* Authors: Dave Updegraff <dave@cray.org>
|
|
* Kumar Gala <galak@kernel.crashing.org>
|
|
* Attribution: from 83xx_wst: Florian Schirmer <jolt@tuxbox.org>
|
|
* ..and from sc520_wdt
|
|
* Copyright (c) 2008 MontaVista Software, Inc.
|
|
* Anton Vorontsov <avorontsov@ru.mvista.com>
|
|
*
|
|
* Note: it appears that you can only actually ENABLE or DISABLE the thing
|
|
* once after POR. Once enabled, you cannot disable, and vice versa.
|
|
*/
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/of_address.h>
|
|
#include <linux/of_platform.h>
|
|
#include <linux/module.h>
|
|
#include <linux/watchdog.h>
|
|
#include <linux/io.h>
|
|
#include <linux/uaccess.h>
|
|
#include <sysdev/fsl_soc.h>
|
|
|
|
#define WATCHDOG_TIMEOUT 10
|
|
|
|
struct mpc8xxx_wdt {
|
|
__be32 res0;
|
|
__be32 swcrr; /* System watchdog control register */
|
|
#define SWCRR_SWTC 0xFFFF0000 /* Software Watchdog Time Count. */
|
|
#define SWCRR_SWF 0x00000008 /* Software Watchdog Freeze (mpc8xx). */
|
|
#define SWCRR_SWEN 0x00000004 /* Watchdog Enable bit. */
|
|
#define SWCRR_SWRI 0x00000002 /* Software Watchdog Reset/Interrupt Select bit.*/
|
|
#define SWCRR_SWPR 0x00000001 /* Software Watchdog Counter Prescale bit. */
|
|
__be32 swcnr; /* System watchdog count register */
|
|
u8 res1[2];
|
|
__be16 swsrr; /* System watchdog service register */
|
|
u8 res2[0xF0];
|
|
};
|
|
|
|
struct mpc8xxx_wdt_type {
|
|
int prescaler;
|
|
bool hw_enabled;
|
|
u32 rsr_mask;
|
|
};
|
|
|
|
struct mpc8xxx_wdt_ddata {
|
|
struct mpc8xxx_wdt __iomem *base;
|
|
struct watchdog_device wdd;
|
|
spinlock_t lock;
|
|
u16 swtc;
|
|
};
|
|
|
|
static u16 timeout;
|
|
module_param(timeout, ushort, 0);
|
|
MODULE_PARM_DESC(timeout,
|
|
"Watchdog timeout in seconds. (1<timeout<65535, default="
|
|
__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
|
|
|
|
static bool reset = 1;
|
|
module_param(reset, bool, 0);
|
|
MODULE_PARM_DESC(reset,
|
|
"Watchdog Interrupt/Reset Mode. 0 = interrupt, 1 = reset");
|
|
|
|
static bool nowayout = WATCHDOG_NOWAYOUT;
|
|
module_param(nowayout, bool, 0);
|
|
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
|
|
"(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
|
|
|
|
static void mpc8xxx_wdt_keepalive(struct mpc8xxx_wdt_ddata *ddata)
|
|
{
|
|
/* Ping the WDT */
|
|
spin_lock(&ddata->lock);
|
|
out_be16(&ddata->base->swsrr, 0x556c);
|
|
out_be16(&ddata->base->swsrr, 0xaa39);
|
|
spin_unlock(&ddata->lock);
|
|
}
|
|
|
|
static int mpc8xxx_wdt_start(struct watchdog_device *w)
|
|
{
|
|
struct mpc8xxx_wdt_ddata *ddata =
|
|
container_of(w, struct mpc8xxx_wdt_ddata, wdd);
|
|
u32 tmp = in_be32(&ddata->base->swcrr);
|
|
|
|
/* Good, fire up the show */
|
|
tmp &= ~(SWCRR_SWTC | SWCRR_SWF | SWCRR_SWEN | SWCRR_SWRI | SWCRR_SWPR);
|
|
tmp |= SWCRR_SWEN | SWCRR_SWPR | (ddata->swtc << 16);
|
|
|
|
if (reset)
|
|
tmp |= SWCRR_SWRI;
|
|
|
|
out_be32(&ddata->base->swcrr, tmp);
|
|
|
|
tmp = in_be32(&ddata->base->swcrr);
|
|
if (!(tmp & SWCRR_SWEN))
|
|
return -EOPNOTSUPP;
|
|
|
|
ddata->swtc = tmp >> 16;
|
|
set_bit(WDOG_HW_RUNNING, &ddata->wdd.status);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mpc8xxx_wdt_ping(struct watchdog_device *w)
|
|
{
|
|
struct mpc8xxx_wdt_ddata *ddata =
|
|
container_of(w, struct mpc8xxx_wdt_ddata, wdd);
|
|
|
|
mpc8xxx_wdt_keepalive(ddata);
|
|
return 0;
|
|
}
|
|
|
|
static struct watchdog_info mpc8xxx_wdt_info = {
|
|
.options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT,
|
|
.firmware_version = 1,
|
|
.identity = "MPC8xxx",
|
|
};
|
|
|
|
static const struct watchdog_ops mpc8xxx_wdt_ops = {
|
|
.owner = THIS_MODULE,
|
|
.start = mpc8xxx_wdt_start,
|
|
.ping = mpc8xxx_wdt_ping,
|
|
};
|
|
|
|
static int mpc8xxx_wdt_probe(struct platform_device *ofdev)
|
|
{
|
|
int ret;
|
|
struct resource *res;
|
|
const struct mpc8xxx_wdt_type *wdt_type;
|
|
struct mpc8xxx_wdt_ddata *ddata;
|
|
u32 freq = fsl_get_sys_freq();
|
|
bool enabled;
|
|
struct device *dev = &ofdev->dev;
|
|
|
|
wdt_type = of_device_get_match_data(dev);
|
|
if (!wdt_type)
|
|
return -EINVAL;
|
|
|
|
if (!freq || freq == -1)
|
|
return -EINVAL;
|
|
|
|
ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
|
|
if (!ddata)
|
|
return -ENOMEM;
|
|
|
|
ddata->base = devm_platform_ioremap_resource(ofdev, 0);
|
|
if (IS_ERR(ddata->base))
|
|
return PTR_ERR(ddata->base);
|
|
|
|
enabled = in_be32(&ddata->base->swcrr) & SWCRR_SWEN;
|
|
if (!enabled && wdt_type->hw_enabled) {
|
|
dev_info(dev, "could not be enabled in software\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
res = platform_get_resource(ofdev, IORESOURCE_MEM, 1);
|
|
if (res) {
|
|
bool status;
|
|
u32 __iomem *rsr = ioremap(res->start, resource_size(res));
|
|
|
|
if (!rsr)
|
|
return -ENOMEM;
|
|
|
|
status = in_be32(rsr) & wdt_type->rsr_mask;
|
|
ddata->wdd.bootstatus = status ? WDIOF_CARDRESET : 0;
|
|
/* clear reset status bits related to watchdog timer */
|
|
out_be32(rsr, wdt_type->rsr_mask);
|
|
iounmap(rsr);
|
|
|
|
dev_info(dev, "Last boot was %scaused by watchdog\n",
|
|
status ? "" : "not ");
|
|
}
|
|
|
|
spin_lock_init(&ddata->lock);
|
|
|
|
ddata->wdd.info = &mpc8xxx_wdt_info;
|
|
ddata->wdd.ops = &mpc8xxx_wdt_ops;
|
|
|
|
ddata->wdd.timeout = WATCHDOG_TIMEOUT;
|
|
watchdog_init_timeout(&ddata->wdd, timeout, dev);
|
|
|
|
watchdog_set_nowayout(&ddata->wdd, nowayout);
|
|
|
|
ddata->swtc = min(ddata->wdd.timeout * freq / wdt_type->prescaler,
|
|
0xffffU);
|
|
|
|
/*
|
|
* If the watchdog was previously enabled or we're running on
|
|
* MPC8xxx, we should ping the wdt from the kernel until the
|
|
* userspace handles it.
|
|
*/
|
|
if (enabled)
|
|
mpc8xxx_wdt_start(&ddata->wdd);
|
|
|
|
ddata->wdd.max_hw_heartbeat_ms = (ddata->swtc * wdt_type->prescaler) /
|
|
(freq / 1000);
|
|
ddata->wdd.min_timeout = ddata->wdd.max_hw_heartbeat_ms / 1000;
|
|
if (ddata->wdd.timeout < ddata->wdd.min_timeout)
|
|
ddata->wdd.timeout = ddata->wdd.min_timeout;
|
|
|
|
ret = devm_watchdog_register_device(dev, &ddata->wdd);
|
|
if (ret)
|
|
return ret;
|
|
|
|
dev_info(dev,
|
|
"WDT driver for MPC8xxx initialized. mode:%s timeout=%d sec\n",
|
|
reset ? "reset" : "interrupt", ddata->wdd.timeout);
|
|
|
|
platform_set_drvdata(ofdev, ddata);
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id mpc8xxx_wdt_match[] = {
|
|
{
|
|
.compatible = "mpc83xx_wdt",
|
|
.data = &(struct mpc8xxx_wdt_type) {
|
|
.prescaler = 0x10000,
|
|
.rsr_mask = BIT(3), /* RSR Bit SWRS */
|
|
},
|
|
},
|
|
{
|
|
.compatible = "fsl,mpc8610-wdt",
|
|
.data = &(struct mpc8xxx_wdt_type) {
|
|
.prescaler = 0x10000,
|
|
.hw_enabled = true,
|
|
.rsr_mask = BIT(20), /* RSTRSCR Bit WDT_RR */
|
|
},
|
|
},
|
|
{
|
|
.compatible = "fsl,mpc823-wdt",
|
|
.data = &(struct mpc8xxx_wdt_type) {
|
|
.prescaler = 0x800,
|
|
.hw_enabled = true,
|
|
.rsr_mask = BIT(28), /* RSR Bit SWRS */
|
|
},
|
|
},
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, mpc8xxx_wdt_match);
|
|
|
|
static struct platform_driver mpc8xxx_wdt_driver = {
|
|
.probe = mpc8xxx_wdt_probe,
|
|
.driver = {
|
|
.name = "mpc8xxx_wdt",
|
|
.of_match_table = mpc8xxx_wdt_match,
|
|
},
|
|
};
|
|
|
|
static int __init mpc8xxx_wdt_init(void)
|
|
{
|
|
return platform_driver_register(&mpc8xxx_wdt_driver);
|
|
}
|
|
arch_initcall(mpc8xxx_wdt_init);
|
|
|
|
static void __exit mpc8xxx_wdt_exit(void)
|
|
{
|
|
platform_driver_unregister(&mpc8xxx_wdt_driver);
|
|
}
|
|
module_exit(mpc8xxx_wdt_exit);
|
|
|
|
MODULE_AUTHOR("Dave Updegraff, Kumar Gala");
|
|
MODULE_DESCRIPTION("Driver for watchdog timer in MPC8xx/MPC83xx/MPC86xx "
|
|
"uProcessors");
|
|
MODULE_LICENSE("GPL");
|