watchdog: sunxi: New watchdog driver for Allwinner A10/A13

This patch adds the driver for the watchdog found in the Allwinner A10 and A13 SoCs. It has DT-support and uses the new watchdog framework. Signed-off-by: Carlo Caione <carlo.caione@gmail.com> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

watchdog: sunxi: New watchdog driver for Allwinner A10/A13
This patch adds the driver for the watchdog found in the Allwinner A10 and A13 SoCs. It has DT-support and uses the new watchdog framework. Signed-off-by: Carlo Caione <carlo.caione@gmail.com> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Carlo Caione · Wim Van Sebroeck
1 parent af4ea6312c
Showing 3 changed files with 248 additions and 0 deletions Side-by-side Diff
drivers/watchdog/Kconfig
drivers/watchdog/Makefile
drivers/watchdog/sunxi_wdt.c
@@ -290,6 +290,16 @@
 	  To compile this driver as a module, choose M here: the
 	  module will be called orion_wdt.
  
+config SUNXI_WATCHDOG
+	tristate "Allwinner SoCs watchdog support"
+	depends on ARCH_SUNXI
+	select WATCHDOG_CORE
+	help
+	  Say Y here to include support for the watchdog timer
+	  in Allwinner SoCs.
+	  To compile this driver as a module, choose M here: the
+	  module will be called sunxi_wdt.
+
 config COH901327_WATCHDOG
 	bool "ST-Ericsson COH 901 327 watchdog"
 	depends on ARCH_U300
@@ -46,6 +46,7 @@
 obj-$(CONFIG_IOP_WATCHDOG) += iop_wdt.o
 obj-$(CONFIG_DAVINCI_WATCHDOG) += davinci_wdt.o
 obj-$(CONFIG_ORION_WATCHDOG) += orion_wdt.o
+obj-$(CONFIG_SUNXI_WATCHDOG) += sunxi_wdt.o
 obj-$(CONFIG_COH901327_WATCHDOG) += coh901327_wdt.o
 obj-$(CONFIG_STMP3XXX_RTC_WATCHDOG) += stmp3xxx_rtc_wdt.o
 obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o
+/*
+ *      sunxi Watchdog Driver
+ *
+ *      Copyright (c) 2013 Carlo Caione
+ *                    2012 Henrik Nordstrom
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ *
+ *      Based on xen_wdt.c
+ *      (c) Copyright 2010 Novell, Inc.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+
+#define WDT_MAX_TIMEOUT         16
+#define WDT_MIN_TIMEOUT         1
+#define WDT_MODE_TIMEOUT(n)     ((n) << 3)
+#define WDT_TIMEOUT_MASK        WDT_MODE_TIMEOUT(0x0F)
+
+#define WDT_CTRL                0x00
+#define WDT_CTRL_RELOAD         ((1 << 0) | (0x0a57 << 1))
+
+#define WDT_MODE                0x04
+#define WDT_MODE_EN             (1 << 0)
+#define WDT_MODE_RST_EN         (1 << 1)
+
+#define DRV_NAME		"sunxi-wdt"
+#define DRV_VERSION		"1.0"
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+static unsigned int timeout = WDT_MAX_TIMEOUT;
+
+struct sunxi_wdt_dev {
+	struct watchdog_device wdt_dev;
+	void __iomem *wdt_base;
+};
+
+/*
+ * wdt_timeout_map maps the watchdog timer interval value in seconds to
+ * the value of the register WDT_MODE bit 3:6
+ *
+ * [timeout seconds] = register value
+ *
+ */
+
+static const int wdt_timeout_map[] = {
+	[1] = 0b0001,  /* 1s  */
+	[2] = 0b0010,  /* 2s  */
+	[3] = 0b0011,  /* 3s  */
+	[4] = 0b0100,  /* 4s  */
+	[5] = 0b0101,  /* 5s  */
+	[6] = 0b0110,  /* 6s  */
+	[8] = 0b0111,  /* 8s  */
+	[10] = 0b1000, /* 10s */
+	[12] = 0b1001, /* 12s */
+	[14] = 0b1010, /* 14s */
+	[16] = 0b1011, /* 16s */
+};
+
+static int sunxi_wdt_ping(struct watchdog_device *wdt_dev)
+{
+	struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
+	void __iomem *wdt_base = sunxi_wdt->wdt_base;
+
+	iowrite32(WDT_CTRL_RELOAD, wdt_base + WDT_CTRL);
+
+	return 0;
+}
+
+static int sunxi_wdt_set_timeout(struct watchdog_device *wdt_dev,
+		unsigned int timeout)
+{
+	struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
+	void __iomem *wdt_base = sunxi_wdt->wdt_base;
+	u32 reg;
+
+	if (wdt_timeout_map[timeout] == 0)
+		timeout++;
+
+	sunxi_wdt->wdt_dev.timeout = timeout;
+
+	reg = ioread32(wdt_base + WDT_MODE);
+	reg &= ~WDT_TIMEOUT_MASK;
+	reg |= WDT_MODE_TIMEOUT(wdt_timeout_map[timeout]);
+	iowrite32(reg, wdt_base + WDT_MODE);
+
+	sunxi_wdt_ping(wdt_dev);
+
+	return 0;
+}
+
+static int sunxi_wdt_stop(struct watchdog_device *wdt_dev)
+{
+	struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
+	void __iomem *wdt_base = sunxi_wdt->wdt_base;
+
+	iowrite32(0, wdt_base + WDT_MODE);
+
+	return 0;
+}
+
+static int sunxi_wdt_start(struct watchdog_device *wdt_dev)
+{
+	u32 reg;
+	struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
+	void __iomem *wdt_base = sunxi_wdt->wdt_base;
+	int ret;
+
+	ret = sunxi_wdt_set_timeout(&sunxi_wdt->wdt_dev,
+			sunxi_wdt->wdt_dev.timeout);
+	if (ret < 0)
+		return ret;
+
+	reg = ioread32(wdt_base + WDT_MODE);
+	reg |= (WDT_MODE_RST_EN | WDT_MODE_EN);
+	iowrite32(reg, wdt_base + WDT_MODE);
+
+	return 0;
+}
+
+static const struct watchdog_info sunxi_wdt_info = {
+	.identity	= DRV_NAME,
+	.options	= WDIOF_SETTIMEOUT |
+			  WDIOF_KEEPALIVEPING |
+			  WDIOF_MAGICCLOSE,
+};
+
+static const struct watchdog_ops sunxi_wdt_ops = {
+	.owner		= THIS_MODULE,
+	.start		= sunxi_wdt_start,
+	.stop		= sunxi_wdt_stop,
+	.ping		= sunxi_wdt_ping,
+	.set_timeout	= sunxi_wdt_set_timeout,
+};
+
+static int __init sunxi_wdt_probe(struct platform_device *pdev)
+{
+	struct sunxi_wdt_dev *sunxi_wdt;
+	struct resource *res;
+	int err;
+
+	sunxi_wdt = devm_kzalloc(&pdev->dev, sizeof(*sunxi_wdt), GFP_KERNEL);
+	if (!sunxi_wdt)
+		return -EINVAL;
+
+	platform_set_drvdata(pdev, sunxi_wdt);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	sunxi_wdt->wdt_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(sunxi_wdt->wdt_base))
+		return PTR_ERR(sunxi_wdt->wdt_base);
+
+	sunxi_wdt->wdt_dev.info = &sunxi_wdt_info;
+	sunxi_wdt->wdt_dev.ops = &sunxi_wdt_ops;
+	sunxi_wdt->wdt_dev.timeout = WDT_MAX_TIMEOUT;
+	sunxi_wdt->wdt_dev.max_timeout = WDT_MAX_TIMEOUT;
+	sunxi_wdt->wdt_dev.min_timeout = WDT_MIN_TIMEOUT;
+	sunxi_wdt->wdt_dev.parent = &pdev->dev;
+
+	watchdog_init_timeout(&sunxi_wdt->wdt_dev, timeout, &pdev->dev);
+	watchdog_set_nowayout(&sunxi_wdt->wdt_dev, nowayout);
+
+	watchdog_set_drvdata(&sunxi_wdt->wdt_dev, sunxi_wdt);
+
+	sunxi_wdt_stop(&sunxi_wdt->wdt_dev);
+
+	err = watchdog_register_device(&sunxi_wdt->wdt_dev);
+	if (unlikely(err))
+		return err;
+
+	dev_info(&pdev->dev, "Watchdog enabled (timeout=%d sec, nowayout=%d)",
+			sunxi_wdt->wdt_dev.timeout, nowayout);
+
+	return 0;
+}
+
+static int __exit sunxi_wdt_remove(struct platform_device *pdev)
+{
+	struct sunxi_wdt_dev *sunxi_wdt = platform_get_drvdata(pdev);
+
+	watchdog_unregister_device(&sunxi_wdt->wdt_dev);
+	watchdog_set_drvdata(&sunxi_wdt->wdt_dev, NULL);
+
+	return 0;
+}
+
+static void sunxi_wdt_shutdown(struct platform_device *pdev)
+{
+	struct sunxi_wdt_dev *sunxi_wdt = platform_get_drvdata(pdev);
+
+	sunxi_wdt_stop(&sunxi_wdt->wdt_dev);
+}
+
+static const struct of_device_id sunxi_wdt_dt_ids[] = {
+	{ .compatible = "allwinner,sun4i-wdt" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, sunxi_wdt_dt_ids);
+
+static struct platform_driver sunxi_wdt_driver = {
+	.probe		= sunxi_wdt_probe,
+	.remove		= sunxi_wdt_remove,
+	.shutdown	= sunxi_wdt_shutdown,
+	.driver		= {
+		.owner		= THIS_MODULE,
+		.name		= DRV_NAME,
+		.of_match_table	= of_match_ptr(sunxi_wdt_dt_ids)
+	},
+};
+
+module_platform_driver(sunxi_wdt_driver);
+
+module_param(timeout, uint, 0);
+MODULE_PARM_DESC(timeout, "Watchdog heartbeat in seconds");
+
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
+		"(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Carlo Caione <carlo.caione@gmail.com>");
+MODULE_AUTHOR("Henrik Nordstrom <henrik@henriknordstrom.net>");
+MODULE_DESCRIPTION("sunxi WatchDog Timer Driver");
+MODULE_VERSION(DRV_VERSION);
...	...	@@ -290,6 +290,16 @@
290	290	To compile this driver as a module, choose M here: the
291	291	module will be called orion_wdt.
292	292
	293	+config SUNXI_WATCHDOG
	294	+ tristate "Allwinner SoCs watchdog support"
	295	+ depends on ARCH_SUNXI
	296	+ select WATCHDOG_CORE
	297	+ help
	298	+ Say Y here to include support for the watchdog timer
	299	+ in Allwinner SoCs.
	300	+ To compile this driver as a module, choose M here: the
	301	+ module will be called sunxi_wdt.
	302	+
293	303	config COH901327_WATCHDOG
294	304	bool "ST-Ericsson COH 901 327 watchdog"
295	305	depends on ARCH_U300
...	...	@@ -46,6 +46,7 @@
46	46	obj-$(CONFIG_IOP_WATCHDOG) += iop_wdt.o
47	47	obj-$(CONFIG_DAVINCI_WATCHDOG) += davinci_wdt.o
48	48	obj-$(CONFIG_ORION_WATCHDOG) += orion_wdt.o
	49	+obj-$(CONFIG_SUNXI_WATCHDOG) += sunxi_wdt.o
49	50	obj-$(CONFIG_COH901327_WATCHDOG) += coh901327_wdt.o
50	51	obj-$(CONFIG_STMP3XXX_RTC_WATCHDOG) += stmp3xxx_rtc_wdt.o
51	52	obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o
	1	+/*
	2	+ * sunxi Watchdog Driver
	3	+ *
	4	+ * Copyright (c) 2013 Carlo Caione
	5	+ * 2012 Henrik Nordstrom
	6	+ *
	7	+ * This program is free software; you can redistribute it and/or
	8	+ * modify it under the terms of the GNU General Public License
	9	+ * as published by the Free Software Foundation; either version
	10	+ * 2 of the License, or (at your option) any later version.
	11	+ *
	12	+ * Based on xen_wdt.c
	13	+ * (c) Copyright 2010 Novell, Inc.
	14	+ */
	15	+
	16	+#include <linux/clk.h>
	17	+#include <linux/err.h>
	18	+#include <linux/init.h>
	19	+#include <linux/io.h>
	20	+#include <linux/kernel.h>
	21	+#include <linux/module.h>
	22	+#include <linux/moduleparam.h>
	23	+#include <linux/of.h>
	24	+#include <linux/platform_device.h>
	25	+#include <linux/types.h>
	26	+#include <linux/watchdog.h>
	27	+
	28	+#define WDT_MAX_TIMEOUT 16
	29	+#define WDT_MIN_TIMEOUT 1
	30	+#define WDT_MODE_TIMEOUT(n) ((n) << 3)
	31	+#define WDT_TIMEOUT_MASK WDT_MODE_TIMEOUT(0x0F)
	32	+
	33	+#define WDT_CTRL 0x00
	34	+#define WDT_CTRL_RELOAD ((1 << 0) \| (0x0a57 << 1))
	35	+
	36	+#define WDT_MODE 0x04
	37	+#define WDT_MODE_EN (1 << 0)
	38	+#define WDT_MODE_RST_EN (1 << 1)
	39	+
	40	+#define DRV_NAME "sunxi-wdt"
	41	+#define DRV_VERSION "1.0"
	42	+
	43	+static bool nowayout = WATCHDOG_NOWAYOUT;
	44	+static unsigned int timeout = WDT_MAX_TIMEOUT;
	45	+
	46	+struct sunxi_wdt_dev {
	47	+ struct watchdog_device wdt_dev;
	48	+ void __iomem *wdt_base;
	49	+};
	50	+
	51	+/*
	52	+ * wdt_timeout_map maps the watchdog timer interval value in seconds to
	53	+ * the value of the register WDT_MODE bit 3:6
	54	+ *
	55	+ * [timeout seconds] = register value
	56	+ *
	57	+ */
	58	+
	59	+static const int wdt_timeout_map[] = {
	60	+ [1] = 0b0001, /* 1s */
	61	+ [2] = 0b0010, /* 2s */
	62	+ [3] = 0b0011, /* 3s */
	63	+ [4] = 0b0100, /* 4s */
	64	+ [5] = 0b0101, /* 5s */
	65	+ [6] = 0b0110, /* 6s */
	66	+ [8] = 0b0111, /* 8s */
	67	+ [10] = 0b1000, /* 10s */
	68	+ [12] = 0b1001, /* 12s */
	69	+ [14] = 0b1010, /* 14s */
	70	+ [16] = 0b1011, /* 16s */
	71	+};
	72	+
	73	+static int sunxi_wdt_ping(struct watchdog_device *wdt_dev)
	74	+{
	75	+ struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
	76	+ void __iomem *wdt_base = sunxi_wdt->wdt_base;
	77	+
	78	+ iowrite32(WDT_CTRL_RELOAD, wdt_base + WDT_CTRL);
	79	+
	80	+ return 0;
	81	+}
	82	+
	83	+static int sunxi_wdt_set_timeout(struct watchdog_device *wdt_dev,
	84	+ unsigned int timeout)
	85	+{
	86	+ struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
	87	+ void __iomem *wdt_base = sunxi_wdt->wdt_base;
	88	+ u32 reg;
	89	+
	90	+ if (wdt_timeout_map[timeout] == 0)
	91	+ timeout++;
	92	+
	93	+ sunxi_wdt->wdt_dev.timeout = timeout;
	94	+
	95	+ reg = ioread32(wdt_base + WDT_MODE);
	96	+ reg &= ~WDT_TIMEOUT_MASK;
	97	+ reg \|= WDT_MODE_TIMEOUT(wdt_timeout_map[timeout]);
	98	+ iowrite32(reg, wdt_base + WDT_MODE);
	99	+
	100	+ sunxi_wdt_ping(wdt_dev);
	101	+
	102	+ return 0;
	103	+}
	104	+
	105	+static int sunxi_wdt_stop(struct watchdog_device *wdt_dev)
	106	+{
	107	+ struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
	108	+ void __iomem *wdt_base = sunxi_wdt->wdt_base;
	109	+
	110	+ iowrite32(0, wdt_base + WDT_MODE);
	111	+
	112	+ return 0;
	113	+}
	114	+
	115	+static int sunxi_wdt_start(struct watchdog_device *wdt_dev)
	116	+{
	117	+ u32 reg;
	118	+ struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
	119	+ void __iomem *wdt_base = sunxi_wdt->wdt_base;
	120	+ int ret;
	121	+
	122	+ ret = sunxi_wdt_set_timeout(&sunxi_wdt->wdt_dev,
	123	+ sunxi_wdt->wdt_dev.timeout);
	124	+ if (ret < 0)
	125	+ return ret;
	126	+
	127	+ reg = ioread32(wdt_base + WDT_MODE);
	128	+ reg \|= (WDT_MODE_RST_EN \| WDT_MODE_EN);
	129	+ iowrite32(reg, wdt_base + WDT_MODE);
	130	+
	131	+ return 0;
	132	+}
	133	+
	134	+static const struct watchdog_info sunxi_wdt_info = {
	135	+ .identity = DRV_NAME,
	136	+ .options = WDIOF_SETTIMEOUT \|
	137	+ WDIOF_KEEPALIVEPING \|
	138	+ WDIOF_MAGICCLOSE,
	139	+};
	140	+
	141	+static const struct watchdog_ops sunxi_wdt_ops = {
	142	+ .owner = THIS_MODULE,
	143	+ .start = sunxi_wdt_start,
	144	+ .stop = sunxi_wdt_stop,
	145	+ .ping = sunxi_wdt_ping,
	146	+ .set_timeout = sunxi_wdt_set_timeout,
	147	+};
	148	+
	149	+static int __init sunxi_wdt_probe(struct platform_device *pdev)
	150	+{
	151	+ struct sunxi_wdt_dev *sunxi_wdt;
	152	+ struct resource *res;
	153	+ int err;
	154	+
	155	+ sunxi_wdt = devm_kzalloc(&pdev->dev, sizeof(*sunxi_wdt), GFP_KERNEL);
	156	+ if (!sunxi_wdt)
	157	+ return -EINVAL;
	158	+
	159	+ platform_set_drvdata(pdev, sunxi_wdt);
	160	+
	161	+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	162	+ sunxi_wdt->wdt_base = devm_ioremap_resource(&pdev->dev, res);
	163	+ if (IS_ERR(sunxi_wdt->wdt_base))
	164	+ return PTR_ERR(sunxi_wdt->wdt_base);
	165	+
	166	+ sunxi_wdt->wdt_dev.info = &sunxi_wdt_info;
	167	+ sunxi_wdt->wdt_dev.ops = &sunxi_wdt_ops;
	168	+ sunxi_wdt->wdt_dev.timeout = WDT_MAX_TIMEOUT;
	169	+ sunxi_wdt->wdt_dev.max_timeout = WDT_MAX_TIMEOUT;
	170	+ sunxi_wdt->wdt_dev.min_timeout = WDT_MIN_TIMEOUT;
	171	+ sunxi_wdt->wdt_dev.parent = &pdev->dev;
	172	+
	173	+ watchdog_init_timeout(&sunxi_wdt->wdt_dev, timeout, &pdev->dev);
	174	+ watchdog_set_nowayout(&sunxi_wdt->wdt_dev, nowayout);
	175	+
	176	+ watchdog_set_drvdata(&sunxi_wdt->wdt_dev, sunxi_wdt);
	177	+
	178	+ sunxi_wdt_stop(&sunxi_wdt->wdt_dev);
	179	+
	180	+ err = watchdog_register_device(&sunxi_wdt->wdt_dev);
	181	+ if (unlikely(err))
	182	+ return err;
	183	+
	184	+ dev_info(&pdev->dev, "Watchdog enabled (timeout=%d sec, nowayout=%d)",
	185	+ sunxi_wdt->wdt_dev.timeout, nowayout);
	186	+
	187	+ return 0;
	188	+}
	189	+
	190	+static int __exit sunxi_wdt_remove(struct platform_device *pdev)
	191	+{
	192	+ struct sunxi_wdt_dev *sunxi_wdt = platform_get_drvdata(pdev);
	193	+
	194	+ watchdog_unregister_device(&sunxi_wdt->wdt_dev);
	195	+ watchdog_set_drvdata(&sunxi_wdt->wdt_dev, NULL);
	196	+
	197	+ return 0;
	198	+}
	199	+
	200	+static void sunxi_wdt_shutdown(struct platform_device *pdev)
	201	+{
	202	+ struct sunxi_wdt_dev *sunxi_wdt = platform_get_drvdata(pdev);
	203	+
	204	+ sunxi_wdt_stop(&sunxi_wdt->wdt_dev);
	205	+}
	206	+
	207	+static const struct of_device_id sunxi_wdt_dt_ids[] = {
	208	+ { .compatible = "allwinner,sun4i-wdt" },
	209	+ { /* sentinel */ }
	210	+};
	211	+MODULE_DEVICE_TABLE(of, sunxi_wdt_dt_ids);
	212	+
	213	+static struct platform_driver sunxi_wdt_driver = {
	214	+ .probe = sunxi_wdt_probe,
	215	+ .remove = sunxi_wdt_remove,
	216	+ .shutdown = sunxi_wdt_shutdown,
	217	+ .driver = {
	218	+ .owner = THIS_MODULE,
	219	+ .name = DRV_NAME,
	220	+ .of_match_table = of_match_ptr(sunxi_wdt_dt_ids)
	221	+ },
	222	+};
	223	+
	224	+module_platform_driver(sunxi_wdt_driver);
	225	+
	226	+module_param(timeout, uint, 0);
	227	+MODULE_PARM_DESC(timeout, "Watchdog heartbeat in seconds");
	228	+
	229	+module_param(nowayout, bool, 0);
	230	+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
	231	+ "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
	232	+
	233	+MODULE_LICENSE("GPL");
	234	+MODULE_AUTHOR("Carlo Caione <carlo.caione@gmail.com>");
	235	+MODULE_AUTHOR("Henrik Nordstrom <henrik@henriknordstrom.net>");
	236	+MODULE_DESCRIPTION("sunxi WatchDog Timer Driver");
	237	+MODULE_VERSION(DRV_VERSION);