diff options
Diffstat (limited to 'drivers/watchdog/imx_sc_wdt.c')
| -rw-r--r-- | drivers/watchdog/imx_sc_wdt.c | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/drivers/watchdog/imx_sc_wdt.c b/drivers/watchdog/imx_sc_wdt.c new file mode 100644 index 000000000000..49848b66186c --- /dev/null +++ b/drivers/watchdog/imx_sc_wdt.c @@ -0,0 +1,175 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2018-2019 NXP. + */ + +#include <linux/arm-smccc.h> +#include <linux/io.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reboot.h> +#include <linux/watchdog.h> + +#define DEFAULT_TIMEOUT 60 +/* + * Software timer tick implemented in scfw side, support 10ms to 0xffffffff ms + * in theory, but for normal case, 1s~128s is enough, you can change this max + * value in case it's not enough. + */ +#define MAX_TIMEOUT 128 + +#define IMX_SIP_TIMER 0xC2000002 +#define IMX_SIP_TIMER_START_WDOG 0x01 +#define IMX_SIP_TIMER_STOP_WDOG 0x02 +#define IMX_SIP_TIMER_SET_WDOG_ACT 0x03 +#define IMX_SIP_TIMER_PING_WDOG 0x04 +#define IMX_SIP_TIMER_SET_TIMEOUT_WDOG 0x05 +#define IMX_SIP_TIMER_GET_WDOG_STAT 0x06 +#define IMX_SIP_TIMER_SET_PRETIME_WDOG 0x07 + +#define SC_TIMER_WDOG_ACTION_PARTITION 0 + +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0000); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +static int imx_sc_wdt_ping(struct watchdog_device *wdog) +{ + struct arm_smccc_res res; + + arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_PING_WDOG, + 0, 0, 0, 0, 0, 0, &res); + + return 0; +} + +static int imx_sc_wdt_start(struct watchdog_device *wdog) +{ + struct arm_smccc_res res; + + arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_START_WDOG, + 0, 0, 0, 0, 0, 0, &res); + if (res.a0) + return -EACCES; + + arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_SET_WDOG_ACT, + SC_TIMER_WDOG_ACTION_PARTITION, + 0, 0, 0, 0, 0, &res); + return res.a0 ? -EACCES : 0; +} + +static int imx_sc_wdt_stop(struct watchdog_device *wdog) +{ + struct arm_smccc_res res; + + arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_STOP_WDOG, + 0, 0, 0, 0, 0, 0, &res); + + return res.a0 ? -EACCES : 0; +} + +static int imx_sc_wdt_set_timeout(struct watchdog_device *wdog, + unsigned int timeout) +{ + struct arm_smccc_res res; + + wdog->timeout = timeout; + arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_SET_TIMEOUT_WDOG, + timeout * 1000, 0, 0, 0, 0, 0, &res); + + return res.a0 ? -EACCES : 0; +} + +static const struct watchdog_ops imx_sc_wdt_ops = { + .owner = THIS_MODULE, + .start = imx_sc_wdt_start, + .stop = imx_sc_wdt_stop, + .ping = imx_sc_wdt_ping, + .set_timeout = imx_sc_wdt_set_timeout, +}; + +static const struct watchdog_info imx_sc_wdt_info = { + .identity = "i.MX SC watchdog timer", + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | + WDIOF_MAGICCLOSE | WDIOF_PRETIMEOUT, +}; + +static int imx_sc_wdt_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct watchdog_device *imx_sc_wdd; + int ret; + + imx_sc_wdd = devm_kzalloc(dev, sizeof(*imx_sc_wdd), GFP_KERNEL); + if (!imx_sc_wdd) + return -ENOMEM; + + platform_set_drvdata(pdev, imx_sc_wdd); + + imx_sc_wdd->info = &imx_sc_wdt_info; + imx_sc_wdd->ops = &imx_sc_wdt_ops; + imx_sc_wdd->min_timeout = 1; + imx_sc_wdd->max_timeout = MAX_TIMEOUT; + imx_sc_wdd->parent = dev; + imx_sc_wdd->timeout = DEFAULT_TIMEOUT; + + watchdog_init_timeout(imx_sc_wdd, 0, dev); + watchdog_stop_on_reboot(imx_sc_wdd); + watchdog_stop_on_unregister(imx_sc_wdd); + + ret = devm_watchdog_register_device(dev, imx_sc_wdd); + if (ret) { + dev_err(dev, "Failed to register watchdog device\n"); + return ret; + } + + return 0; +} + +static int __maybe_unused imx_sc_wdt_suspend(struct device *dev) +{ + struct watchdog_device *imx_sc_wdd = dev_get_drvdata(dev); + + if (watchdog_active(imx_sc_wdd)) + imx_sc_wdt_stop(imx_sc_wdd); + + return 0; +} + +static int __maybe_unused imx_sc_wdt_resume(struct device *dev) +{ + struct watchdog_device *imx_sc_wdd = dev_get_drvdata(dev); + + if (watchdog_active(imx_sc_wdd)) + imx_sc_wdt_start(imx_sc_wdd); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(imx_sc_wdt_pm_ops, + imx_sc_wdt_suspend, imx_sc_wdt_resume); + +static const struct of_device_id imx_sc_wdt_dt_ids[] = { + { .compatible = "fsl,imx-sc-wdt", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, imx_sc_wdt_dt_ids); + +static struct platform_driver imx_sc_wdt_driver = { + .probe = imx_sc_wdt_probe, + .driver = { + .name = "imx-sc-wdt", + .of_match_table = imx_sc_wdt_dt_ids, + .pm = &imx_sc_wdt_pm_ops, + }, +}; +module_platform_driver(imx_sc_wdt_driver); + +MODULE_AUTHOR("Robin Gong <yibin.gong@nxp.com>"); +MODULE_DESCRIPTION("NXP i.MX system controller watchdog driver"); +MODULE_LICENSE("GPL v2"); |