Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 266 insertions, 0 deletions

diff --git a/drivers/watchdog/npcm_wdt.c b/drivers/watchdog/npcm_wdt.c
new file mode 100644
index 000000000..a5dd1c230
--- /dev/null
+++ b/drivers/watchdog/npcm_wdt.c
@@ -0,0 +1,266 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018 Nuvoton Technology corporation.
+// Copyright (c) 2018 IBM Corp.
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/watchdog.h>
+
+#define NPCM_WTCR	0x1C
+
+#define NPCM_WTCLK	(BIT(10) | BIT(11))	/* Clock divider */
+#define NPCM_WTE	BIT(7)			/* Enable */
+#define NPCM_WTIE	BIT(6)			/* Enable irq */
+#define NPCM_WTIS	(BIT(4) | BIT(5))	/* Interval selection */
+#define NPCM_WTIF	BIT(3)			/* Interrupt flag*/
+#define NPCM_WTRF	BIT(2)			/* Reset flag */
+#define NPCM_WTRE	BIT(1)			/* Reset enable */
+#define NPCM_WTR	BIT(0)			/* Reset counter */
+
+/*
+ * Watchdog timeouts
+ *
+ * 170     msec:    WTCLK=01 WTIS=00     VAL= 0x400
+ * 670     msec:    WTCLK=01 WTIS=01     VAL= 0x410
+ * 1360    msec:    WTCLK=10 WTIS=00     VAL= 0x800
+ * 2700    msec:    WTCLK=01 WTIS=10     VAL= 0x420
+ * 5360    msec:    WTCLK=10 WTIS=01     VAL= 0x810
+ * 10700   msec:    WTCLK=01 WTIS=11     VAL= 0x430
+ * 21600   msec:    WTCLK=10 WTIS=10     VAL= 0x820
+ * 43000   msec:    WTCLK=11 WTIS=00     VAL= 0xC00
+ * 85600   msec:    WTCLK=10 WTIS=11     VAL= 0x830
+ * 172000  msec:    WTCLK=11 WTIS=01     VAL= 0xC10
+ * 687000  msec:    WTCLK=11 WTIS=10     VAL= 0xC20
+ * 2750000 msec:    WTCLK=11 WTIS=11     VAL= 0xC30
+ */
+
+struct npcm_wdt {
+	struct watchdog_device  wdd;
+	void __iomem		*reg;
+	struct clk		*clk;
+};
+
+static inline struct npcm_wdt *to_npcm_wdt(struct watchdog_device *wdd)
+{
+	return container_of(wdd, struct npcm_wdt, wdd);
+}
+
+static int npcm_wdt_ping(struct watchdog_device *wdd)
+{
+	struct npcm_wdt *wdt = to_npcm_wdt(wdd);
+	u32 val;
+
+	val = readl(wdt->reg);
+	writel(val | NPCM_WTR, wdt->reg);
+
+	return 0;
+}
+
+static int npcm_wdt_start(struct watchdog_device *wdd)
+{
+	struct npcm_wdt *wdt = to_npcm_wdt(wdd);
+	u32 val;
+
+	if (wdt->clk)
+		clk_prepare_enable(wdt->clk);
+
+	if (wdd->timeout < 2)
+		val = 0x800;
+	else if (wdd->timeout < 3)
+		val = 0x420;
+	else if (wdd->timeout < 6)
+		val = 0x810;
+	else if (wdd->timeout < 11)
+		val = 0x430;
+	else if (wdd->timeout < 22)
+		val = 0x820;
+	else if (wdd->timeout < 44)
+		val = 0xC00;
+	else if (wdd->timeout < 87)
+		val = 0x830;
+	else if (wdd->timeout < 173)
+		val = 0xC10;
+	else if (wdd->timeout < 688)
+		val = 0xC20;
+	else
+		val = 0xC30;
+
+	val |= NPCM_WTRE | NPCM_WTE | NPCM_WTR | NPCM_WTIE;
+
+	writel(val, wdt->reg);
+
+	return 0;
+}
+
+static int npcm_wdt_stop(struct watchdog_device *wdd)
+{
+	struct npcm_wdt *wdt = to_npcm_wdt(wdd);
+
+	writel(0, wdt->reg);
+
+	if (wdt->clk)
+		clk_disable_unprepare(wdt->clk);
+
+	return 0;
+}
+
+static int npcm_wdt_set_timeout(struct watchdog_device *wdd,
+				unsigned int timeout)
+{
+	if (timeout < 2)
+		wdd->timeout = 1;
+	else if (timeout < 3)
+		wdd->timeout = 2;
+	else if (timeout < 6)
+		wdd->timeout = 5;
+	else if (timeout < 11)
+		wdd->timeout = 10;
+	else if (timeout < 22)
+		wdd->timeout = 21;
+	else if (timeout < 44)
+		wdd->timeout = 43;
+	else if (timeout < 87)
+		wdd->timeout = 86;
+	else if (timeout < 173)
+		wdd->timeout = 172;
+	else if (timeout < 688)
+		wdd->timeout = 687;
+	else
+		wdd->timeout = 2750;
+
+	if (watchdog_active(wdd))
+		npcm_wdt_start(wdd);
+
+	return 0;
+}
+
+static irqreturn_t npcm_wdt_interrupt(int irq, void *data)
+{
+	struct npcm_wdt *wdt = data;
+
+	watchdog_notify_pretimeout(&wdt->wdd);
+
+	return IRQ_HANDLED;
+}
+
+static int npcm_wdt_restart(struct watchdog_device *wdd,
+			    unsigned long action, void *data)
+{
+	struct npcm_wdt *wdt = to_npcm_wdt(wdd);
+
+	/* For reset, we start the WDT clock and leave it running. */
+	if (wdt->clk)
+		clk_prepare_enable(wdt->clk);
+
+	writel(NPCM_WTR | NPCM_WTRE | NPCM_WTE, wdt->reg);
+	udelay(1000);
+
+	return 0;
+}
+
+static bool npcm_is_running(struct watchdog_device *wdd)
+{
+	struct npcm_wdt *wdt = to_npcm_wdt(wdd);
+
+	return readl(wdt->reg) & NPCM_WTE;
+}
+
+static const struct watchdog_info npcm_wdt_info = {
+	.identity	= KBUILD_MODNAME,
+	.options	= WDIOF_SETTIMEOUT
+			| WDIOF_KEEPALIVEPING
+			| WDIOF_MAGICCLOSE,
+};
+
+static const struct watchdog_ops npcm_wdt_ops = {
+	.owner = THIS_MODULE,
+	.start = npcm_wdt_start,
+	.stop = npcm_wdt_stop,
+	.ping = npcm_wdt_ping,
+	.set_timeout = npcm_wdt_set_timeout,
+	.restart = npcm_wdt_restart,
+};
+
+static int npcm_wdt_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct npcm_wdt *wdt;
+	int irq;
+	int ret;
+
+	wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
+	if (!wdt)
+		return -ENOMEM;
+
+	wdt->reg = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(wdt->reg))
+		return PTR_ERR(wdt->reg);
+
+	wdt->clk = devm_clk_get_optional(&pdev->dev, NULL);
+	if (IS_ERR(wdt->clk))
+		return PTR_ERR(wdt->clk);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	wdt->wdd.info = &npcm_wdt_info;
+	wdt->wdd.ops = &npcm_wdt_ops;
+	wdt->wdd.min_timeout = 1;
+	wdt->wdd.max_timeout = 2750;
+	wdt->wdd.parent = dev;
+
+	wdt->wdd.timeout = 86;
+	watchdog_init_timeout(&wdt->wdd, 0, dev);
+
+	/* Ensure timeout is able to be represented by the hardware */
+	npcm_wdt_set_timeout(&wdt->wdd, wdt->wdd.timeout);
+
+	if (npcm_is_running(&wdt->wdd)) {
+		/* Restart with the default or device-tree specified timeout */
+		npcm_wdt_start(&wdt->wdd);
+		set_bit(WDOG_HW_RUNNING, &wdt->wdd.status);
+	}
+
+	ret = devm_request_irq(dev, irq, npcm_wdt_interrupt, 0, "watchdog",
+			       wdt);
+	if (ret)
+		return ret;
+
+	ret = devm_watchdog_register_device(dev, &wdt->wdd);
+	if (ret)
+		return ret;
+
+	dev_info(dev, "NPCM watchdog driver enabled\n");
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id npcm_wdt_match[] = {
+	{.compatible = "nuvoton,wpcm450-wdt"},
+	{.compatible = "nuvoton,npcm750-wdt"},
+	{},
+};
+MODULE_DEVICE_TABLE(of, npcm_wdt_match);
+#endif
+
+static struct platform_driver npcm_wdt_driver = {
+	.probe		= npcm_wdt_probe,
+	.driver		= {
+		.name	= "npcm-wdt",
+		.of_match_table = of_match_ptr(npcm_wdt_match),
+	},
+};
+module_platform_driver(npcm_wdt_driver);
+
+MODULE_AUTHOR("Joel Stanley");
+MODULE_DESCRIPTION("Watchdog driver for NPCM");
+MODULE_LICENSE("GPL v2");