1 // SPDX-License-Identifier: GPL-2.0
3  * Watchdog driver for the K3 RTI module
5  * (c) Copyright 2019-2020 Texas Instruments Inc.
67  * struct to hold data for each WDT device
68  * @base - base io address of WD device
69  * @freq - source clock frequency of WDT
70  * @wdd  - hold watchdog device as is in WDT core
81 	struct rti_wdt_device *wdt = watchdog_get_drvdata(wdd);  in rti_wdt_start()  local
84 	ret = pm_runtime_resume_and_get(wdd->parent);  in rti_wdt_start()
89 	timer_margin = (u64)wdd->timeout * wdt->freq;  in rti_wdt_start()
93 	writel_relaxed(timer_margin, wdt->base + RTIDWDPRLD);  in rti_wdt_start()
96 	 * RTI only supports a windowed mode, where the watchdog can only  in rti_wdt_start()
102 	wdd->min_hw_heartbeat_ms = 520 * wdd->timeout + MAX_HW_ERROR;  in rti_wdt_start()
104 	/* Generate NMI when wdt expires */  in rti_wdt_start()
105 	writel_relaxed(RTIWWDRX_NMI, wdt->base + RTIWWDRXCTRL);  in rti_wdt_start()
108 	writel_relaxed(RTIWWDSIZE_50P, wdt->base + RTIWWDSIZECTRL);  in rti_wdt_start()
110 	readl_relaxed(wdt->base + RTIWWDSIZECTRL);  in rti_wdt_start()
113 	writel_relaxed(WDENABLE_KEY, wdt->base + RTIDWDCTRL);  in rti_wdt_start()
119 	struct rti_wdt_device *wdt = watchdog_get_drvdata(wdd);  in rti_wdt_ping()  local
122 	writel_relaxed(WDKEY_SEQ0, wdt->base + RTIWDKEY);  in rti_wdt_ping()
124 	writel_relaxed(WDKEY_SEQ1, wdt->base + RTIWDKEY);  in rti_wdt_ping()
132 	 * RTI only supports a windowed mode, where the watchdog can only  in rti_wdt_setup_hw_hb()
142 		wdd->min_hw_heartbeat_ms = 520 * heartbeat + MAX_HW_ERROR;  in rti_wdt_setup_hw_hb()
147 		wdd->min_hw_heartbeat_ms = 770 * heartbeat + MAX_HW_ERROR;  in rti_wdt_setup_hw_hb()
152 		wdd->min_hw_heartbeat_ms = 895 * heartbeat + MAX_HW_ERROR;  in rti_wdt_setup_hw_hb()
157 		wdd->min_hw_heartbeat_ms = 955 * heartbeat + MAX_HW_ERROR;  in rti_wdt_setup_hw_hb()
162 		wdd->min_hw_heartbeat_ms = 989 * heartbeat + MAX_HW_ERROR;  in rti_wdt_setup_hw_hb()
166 		return -EINVAL;  in rti_wdt_setup_hw_hb()
176 	struct rti_wdt_device *wdt = watchdog_get_drvdata(wdd);  in rti_wdt_get_timeleft_ms()  local
179 	val = readl_relaxed(wdt->base + RTIWDSTATUS);  in rti_wdt_get_timeleft_ms()
183 	timer_counter = readl_relaxed(wdt->base + RTIDWDCNTR);  in rti_wdt_get_timeleft_ms()
187 	do_div(timer_counter, wdt->freq);  in rti_wdt_get_timeleft_ms()
199 	.identity = "K3 RTI Watchdog",
212 	struct device *dev = &pdev->dev;  in rti_wdt_probe()
214 	struct rti_wdt_device *wdt;  in rti_wdt_probe()  local
222 	wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);  in rti_wdt_probe()
223 	if (!wdt)  in rti_wdt_probe()
224 		return -ENOMEM;  in rti_wdt_probe()
230 	wdt->freq = clk_get_rate(clk);  in rti_wdt_probe()
234 	if (!wdt->freq) {  in rti_wdt_probe()
236 		return -EINVAL;  in rti_wdt_probe()
242 		pm_runtime_disable(&pdev->dev);  in rti_wdt_probe()
246 	platform_set_drvdata(pdev, wdt);  in rti_wdt_probe()
248 	wdd = &wdt->wdd;  in rti_wdt_probe()
249 	wdd->info = &rti_wdt_info;  in rti_wdt_probe()
250 	wdd->ops = &rti_wdt_ops;  in rti_wdt_probe()
251 	wdd->min_timeout = 1;  in rti_wdt_probe()
252 	wdd->max_hw_heartbeat_ms = (WDT_PRELOAD_MAX << WDT_PRELOAD_SHIFT) /  in rti_wdt_probe()
253 		wdt->freq * 1000;  in rti_wdt_probe()
254 	wdd->timeout = DEFAULT_HEARTBEAT;  in rti_wdt_probe()
255 	wdd->parent = dev;  in rti_wdt_probe()
257 	watchdog_set_drvdata(wdd, wdt);  in rti_wdt_probe()
261 	wdt->base = devm_platform_ioremap_resource(pdev, 0);  in rti_wdt_probe()
262 	if (IS_ERR(wdt->base)) {  in rti_wdt_probe()
263 		ret = PTR_ERR(wdt->base);  in rti_wdt_probe()
267 	if (readl(wdt->base + RTIDWDCTRL) == WDENABLE_KEY) {  in rti_wdt_probe()
273 		set_bit(WDOG_HW_RUNNING, &wdd->status);  in rti_wdt_probe()
276 		heartbeat_ms = readl(wdt->base + RTIDWDPRLD) + 1;  in rti_wdt_probe()
279 		do_div(heartbeat_ms, wdt->freq);  in rti_wdt_probe()
287 		wsize = readl(wdt->base + RTIWWDSIZECTRL);  in rti_wdt_probe()
294 		last_ping = heartbeat_ms - time_left_ms;  in rti_wdt_probe()
301 	ret = of_reserved_mem_region_to_resource(pdev->dev.of_node, 0, &res);  in rti_wdt_probe()
305 		 * Readout the Power-on(PON) reason and pass to bootstatus.  in rti_wdt_probe()
311 			ret = -EINVAL;  in rti_wdt_probe()
317 			dev_err(dev, "Failed to map memory-region.\n");  in rti_wdt_probe()
318 			ret = -ENOMEM;  in rti_wdt_probe()
325 			wdd->bootstatus |= WDIOF_CARDRESET;  in rti_wdt_probe()
341 		pm_runtime_put_sync(&pdev->dev);  in rti_wdt_probe()
346 	pm_runtime_put_sync(&pdev->dev);  in rti_wdt_probe()
347 	pm_runtime_disable(&pdev->dev);  in rti_wdt_probe()
354 	struct rti_wdt_device *wdt = platform_get_drvdata(pdev);  in rti_wdt_remove()  local
356 	watchdog_unregister_device(&wdt->wdd);  in rti_wdt_remove()
358 	if (!pm_runtime_suspended(&pdev->dev))  in rti_wdt_remove()
359 		pm_runtime_put(&pdev->dev);  in rti_wdt_remove()
361 	pm_runtime_disable(&pdev->dev);  in rti_wdt_remove()
365 	{ .compatible = "ti,j7-rti-wdt", },
372 		.name = "rti-wdt",
381 MODULE_AUTHOR("Tero Kristo <t-kristo@ti.com>");
382 MODULE_DESCRIPTION("K3 RTI Watchdog Driver");
391 MODULE_ALIAS("platform:rti-wdt");