1 // SPDX-License-Identifier: GPL-2.0-only
5  * Watchdog driver for Intel IXP4xx network processors
21 #include <linux/soc/ixp4xx/cpu.h>
32 /* Registers after the timer registers */
33 #define IXP4XX_OSWT_OFFSET	0x14  /* Watchdog Timer */
36 #define IXP4XX_OSST_OFFSET	0x20  /* Timer Status */
55 	__raw_writel(IXP4XX_WDT_KEY, iwdt->base + IXP4XX_OSWK_OFFSET);  in ixp4xx_wdt_start()
56 	__raw_writel(0, iwdt->base + IXP4XX_OSWE_OFFSET);  in ixp4xx_wdt_start()
57 	__raw_writel(wdd->timeout * iwdt->rate,  in ixp4xx_wdt_start()
58 		     iwdt->base + IXP4XX_OSWT_OFFSET);  in ixp4xx_wdt_start()
60 		     iwdt->base + IXP4XX_OSWE_OFFSET);  in ixp4xx_wdt_start()
61 	__raw_writel(0, iwdt->base + IXP4XX_OSWK_OFFSET);  in ixp4xx_wdt_start()
70 	__raw_writel(IXP4XX_WDT_KEY, iwdt->base + IXP4XX_OSWK_OFFSET);  in ixp4xx_wdt_stop()
71 	__raw_writel(0, iwdt->base + IXP4XX_OSWE_OFFSET);  in ixp4xx_wdt_stop()
72 	__raw_writel(0, iwdt->base + IXP4XX_OSWK_OFFSET);  in ixp4xx_wdt_stop()
80 	wdd->timeout = timeout;  in ixp4xx_wdt_set_timeout()
92 	__raw_writel(IXP4XX_WDT_KEY, iwdt->base + IXP4XX_OSWK_OFFSET);  in ixp4xx_wdt_restart()
93 	__raw_writel(0, iwdt->base + IXP4XX_OSWT_OFFSET);  in ixp4xx_wdt_restart()
95 		     iwdt->base + IXP4XX_OSWE_OFFSET);  in ixp4xx_wdt_restart()
115 /* Devres-handled clock disablement */
123 	struct device *dev = &pdev->dev;  in ixp4xx_wdt_probe()
129 		dev_err(dev, "Rev. A0 IXP42x CPU detected - watchdog disabled\n");  in ixp4xx_wdt_probe()
130 		return -ENODEV;  in ixp4xx_wdt_probe()
135 		return -ENOMEM;  in ixp4xx_wdt_probe()
136 	iwdt->base = (void __iomem *)dev->platform_data;  in ixp4xx_wdt_probe()
142 	clk = devm_clk_get(dev->parent, NULL);  in ixp4xx_wdt_probe()
150 		iwdt->rate = clk_get_rate(clk);  in ixp4xx_wdt_probe()
152 	if (!iwdt->rate)  in ixp4xx_wdt_probe()
153 		iwdt->rate = IXP4XX_TIMER_FREQ;  in ixp4xx_wdt_probe()
155 	iwdt->wdd.info = &ixp4xx_wdt_info;  in ixp4xx_wdt_probe()
156 	iwdt->wdd.ops = &ixp4xx_wdt_ops;  in ixp4xx_wdt_probe()
157 	iwdt->wdd.min_timeout = 1;  in ixp4xx_wdt_probe()
158 	iwdt->wdd.max_timeout = U32_MAX / iwdt->rate;  in ixp4xx_wdt_probe()
159 	iwdt->wdd.parent = dev;  in ixp4xx_wdt_probe()
161 	iwdt->wdd.timeout = 60U;  in ixp4xx_wdt_probe()
162 	watchdog_init_timeout(&iwdt->wdd, 0, dev);  in ixp4xx_wdt_probe()
164 	if (__raw_readl(iwdt->base + IXP4XX_OSST_OFFSET) &  in ixp4xx_wdt_probe()
166 		iwdt->wdd.bootstatus = WDIOF_CARDRESET;  in ixp4xx_wdt_probe()
168 	ret = devm_watchdog_register_device(dev, &iwdt->wdd);  in ixp4xx_wdt_probe()
172 	dev_info(dev, "IXP4xx watchdog available\n");  in ixp4xx_wdt_probe()
180 		.name   = "ixp4xx-watchdog",
186 MODULE_DESCRIPTION("IXP4xx Network Processor Watchdog");