@@ -641,6 +641,22 @@ config IMX2_WDT
To compile this driver as a module, choose M here: the
module will be called imx2_wdt.
+config IMX_SC_WDT
+ tristate "IMX SC Watchdog"
+ depends on HAVE_ARM_SMCCC
+ select WATCHDOG_CORE
+ help
+ This is the driver for the system controller watchdog
+ on the NXP i.MX SoCs with system controller inside, the
+ watchdog driver will call ARM SMC API and trap into
+ ARM-Trusted-Firmware for operations, ARM-Trusted-Firmware
+ will request system controller to execute the operations.
+ If you have one of these processors and wish to have
+ watchdog support enabled, say Y, otherwise say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called imx_sc_wdt.
+
config UX500_WATCHDOG
tristate "ST-Ericsson Ux500 watchdog"
depends on MFD_DB8500_PRCMU
@@ -68,6 +68,7 @@ obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o
obj-$(CONFIG_TS4800_WATCHDOG) += ts4800_wdt.o
obj-$(CONFIG_TS72XX_WATCHDOG) += ts72xx_wdt.o
obj-$(CONFIG_IMX2_WDT) += imx2_wdt.o
+obj-$(CONFIG_IMX_SC_WDT) += imx_sc_wdt.o
obj-$(CONFIG_UX500_WATCHDOG) += ux500_wdt.o
obj-$(CONFIG_RETU_WATCHDOG) += retu_wdt.o
obj-$(CONFIG_BCM2835_WDT) += bcm2835_wdt.o
new file mode 100644
@@ -0,0 +1,177 @@
+// 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 watchdog_device *imx_sc_wdd;
+ int ret;
+
+ imx_sc_wdd = devm_kzalloc(&pdev->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 = &pdev->dev;
+ imx_sc_wdd->timeout = DEFAULT_TIMEOUT;
+
+ ret = watchdog_init_timeout(imx_sc_wdd, 0, &pdev->dev);
+ if (ret)
+ dev_warn(&pdev->dev, "Failed to set timeout value, using default\n");
+
+ watchdog_stop_on_reboot(imx_sc_wdd);
+ watchdog_stop_on_unregister(imx_sc_wdd);
+
+ ret = devm_watchdog_register_device(&pdev->dev, imx_sc_wdd);
+ if (ret) {
+ dev_err(&pdev->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");