summaryrefslogtreecommitdiffstats
path: root/drivers/watchdog/mtk_wdt.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/watchdog/mtk_wdt.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--drivers/watchdog/mtk_wdt.c462
1 files changed, 462 insertions, 0 deletions
diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c
new file mode 100644
index 000000000..e97787536
--- /dev/null
+++ b/drivers/watchdog/mtk_wdt.c
@@ -0,0 +1,462 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Mediatek Watchdog Driver
+ *
+ * Copyright (C) 2014 Matthias Brugger
+ *
+ * Matthias Brugger <matthias.bgg@gmail.com>
+ *
+ * Based on sunxi_wdt.c
+ */
+
+#include <dt-bindings/reset/mt2712-resets.h>
+#include <dt-bindings/reset/mt7986-resets.h>
+#include <dt-bindings/reset/mt8183-resets.h>
+#include <dt-bindings/reset/mt8186-resets.h>
+#include <dt-bindings/reset/mt8192-resets.h>
+#include <dt-bindings/reset/mt8195-resets.h>
+#include <linux/delay.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/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+#include <linux/interrupt.h>
+
+#define WDT_MAX_TIMEOUT 31
+#define WDT_MIN_TIMEOUT 2
+#define WDT_LENGTH_TIMEOUT(n) ((n) << 5)
+
+#define WDT_LENGTH 0x04
+#define WDT_LENGTH_KEY 0x8
+
+#define WDT_RST 0x08
+#define WDT_RST_RELOAD 0x1971
+
+#define WDT_MODE 0x00
+#define WDT_MODE_EN (1 << 0)
+#define WDT_MODE_EXT_POL_LOW (0 << 1)
+#define WDT_MODE_EXT_POL_HIGH (1 << 1)
+#define WDT_MODE_EXRST_EN (1 << 2)
+#define WDT_MODE_IRQ_EN (1 << 3)
+#define WDT_MODE_AUTO_START (1 << 4)
+#define WDT_MODE_DUAL_EN (1 << 6)
+#define WDT_MODE_KEY 0x22000000
+
+#define WDT_SWRST 0x14
+#define WDT_SWRST_KEY 0x1209
+
+#define WDT_SWSYSRST 0x18U
+#define WDT_SWSYS_RST_KEY 0x88000000
+
+#define DRV_NAME "mtk-wdt"
+#define DRV_VERSION "1.0"
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+static unsigned int timeout;
+
+struct mtk_wdt_dev {
+ struct watchdog_device wdt_dev;
+ void __iomem *wdt_base;
+ spinlock_t lock; /* protects WDT_SWSYSRST reg */
+ struct reset_controller_dev rcdev;
+ bool disable_wdt_extrst;
+};
+
+struct mtk_wdt_data {
+ int toprgu_sw_rst_num;
+};
+
+static const struct mtk_wdt_data mt2712_data = {
+ .toprgu_sw_rst_num = MT2712_TOPRGU_SW_RST_NUM,
+};
+
+static const struct mtk_wdt_data mt7986_data = {
+ .toprgu_sw_rst_num = MT7986_TOPRGU_SW_RST_NUM,
+};
+
+static const struct mtk_wdt_data mt8183_data = {
+ .toprgu_sw_rst_num = MT8183_TOPRGU_SW_RST_NUM,
+};
+
+static const struct mtk_wdt_data mt8186_data = {
+ .toprgu_sw_rst_num = MT8186_TOPRGU_SW_RST_NUM,
+};
+
+static const struct mtk_wdt_data mt8192_data = {
+ .toprgu_sw_rst_num = MT8192_TOPRGU_SW_RST_NUM,
+};
+
+static const struct mtk_wdt_data mt8195_data = {
+ .toprgu_sw_rst_num = MT8195_TOPRGU_SW_RST_NUM,
+};
+
+static int toprgu_reset_update(struct reset_controller_dev *rcdev,
+ unsigned long id, bool assert)
+{
+ unsigned int tmp;
+ unsigned long flags;
+ struct mtk_wdt_dev *data =
+ container_of(rcdev, struct mtk_wdt_dev, rcdev);
+
+ spin_lock_irqsave(&data->lock, flags);
+
+ tmp = readl(data->wdt_base + WDT_SWSYSRST);
+ if (assert)
+ tmp |= BIT(id);
+ else
+ tmp &= ~BIT(id);
+ tmp |= WDT_SWSYS_RST_KEY;
+ writel(tmp, data->wdt_base + WDT_SWSYSRST);
+
+ spin_unlock_irqrestore(&data->lock, flags);
+
+ return 0;
+}
+
+static int toprgu_reset_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return toprgu_reset_update(rcdev, id, true);
+}
+
+static int toprgu_reset_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return toprgu_reset_update(rcdev, id, false);
+}
+
+static int toprgu_reset(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ int ret;
+
+ ret = toprgu_reset_assert(rcdev, id);
+ if (ret)
+ return ret;
+
+ return toprgu_reset_deassert(rcdev, id);
+}
+
+static const struct reset_control_ops toprgu_reset_ops = {
+ .assert = toprgu_reset_assert,
+ .deassert = toprgu_reset_deassert,
+ .reset = toprgu_reset,
+};
+
+static int toprgu_register_reset_controller(struct platform_device *pdev,
+ int rst_num)
+{
+ int ret;
+ struct mtk_wdt_dev *mtk_wdt = platform_get_drvdata(pdev);
+
+ spin_lock_init(&mtk_wdt->lock);
+
+ mtk_wdt->rcdev.owner = THIS_MODULE;
+ mtk_wdt->rcdev.nr_resets = rst_num;
+ mtk_wdt->rcdev.ops = &toprgu_reset_ops;
+ mtk_wdt->rcdev.of_node = pdev->dev.of_node;
+ ret = devm_reset_controller_register(&pdev->dev, &mtk_wdt->rcdev);
+ if (ret != 0)
+ dev_err(&pdev->dev,
+ "couldn't register wdt reset controller: %d\n", ret);
+ return ret;
+}
+
+static int mtk_wdt_restart(struct watchdog_device *wdt_dev,
+ unsigned long action, void *data)
+{
+ struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev);
+ void __iomem *wdt_base;
+
+ wdt_base = mtk_wdt->wdt_base;
+
+ while (1) {
+ writel(WDT_SWRST_KEY, wdt_base + WDT_SWRST);
+ mdelay(5);
+ }
+
+ return 0;
+}
+
+static int mtk_wdt_ping(struct watchdog_device *wdt_dev)
+{
+ struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev);
+ void __iomem *wdt_base = mtk_wdt->wdt_base;
+
+ iowrite32(WDT_RST_RELOAD, wdt_base + WDT_RST);
+
+ return 0;
+}
+
+static int mtk_wdt_set_timeout(struct watchdog_device *wdt_dev,
+ unsigned int timeout)
+{
+ struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev);
+ void __iomem *wdt_base = mtk_wdt->wdt_base;
+ u32 reg;
+
+ wdt_dev->timeout = timeout;
+ /*
+ * In dual mode, irq will be triggered at timeout / 2
+ * the real timeout occurs at timeout
+ */
+ if (wdt_dev->pretimeout)
+ wdt_dev->pretimeout = timeout / 2;
+
+ /*
+ * One bit is the value of 512 ticks
+ * The clock has 32 KHz
+ */
+ reg = WDT_LENGTH_TIMEOUT((timeout - wdt_dev->pretimeout) << 6)
+ | WDT_LENGTH_KEY;
+ iowrite32(reg, wdt_base + WDT_LENGTH);
+
+ mtk_wdt_ping(wdt_dev);
+
+ return 0;
+}
+
+static void mtk_wdt_init(struct watchdog_device *wdt_dev)
+{
+ struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev);
+ void __iomem *wdt_base;
+
+ wdt_base = mtk_wdt->wdt_base;
+
+ if (readl(wdt_base + WDT_MODE) & WDT_MODE_EN) {
+ set_bit(WDOG_HW_RUNNING, &wdt_dev->status);
+ mtk_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
+ }
+}
+
+static int mtk_wdt_stop(struct watchdog_device *wdt_dev)
+{
+ struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev);
+ void __iomem *wdt_base = mtk_wdt->wdt_base;
+ u32 reg;
+
+ reg = readl(wdt_base + WDT_MODE);
+ reg &= ~WDT_MODE_EN;
+ reg |= WDT_MODE_KEY;
+ iowrite32(reg, wdt_base + WDT_MODE);
+
+ return 0;
+}
+
+static int mtk_wdt_start(struct watchdog_device *wdt_dev)
+{
+ u32 reg;
+ struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev);
+ void __iomem *wdt_base = mtk_wdt->wdt_base;
+ int ret;
+
+ ret = mtk_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
+ if (ret < 0)
+ return ret;
+
+ reg = ioread32(wdt_base + WDT_MODE);
+ if (wdt_dev->pretimeout)
+ reg |= (WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN);
+ else
+ reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN);
+ if (mtk_wdt->disable_wdt_extrst)
+ reg &= ~WDT_MODE_EXRST_EN;
+ reg |= (WDT_MODE_EN | WDT_MODE_KEY);
+ iowrite32(reg, wdt_base + WDT_MODE);
+
+ return 0;
+}
+
+static int mtk_wdt_set_pretimeout(struct watchdog_device *wdd,
+ unsigned int timeout)
+{
+ struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdd);
+ void __iomem *wdt_base = mtk_wdt->wdt_base;
+ u32 reg = ioread32(wdt_base + WDT_MODE);
+
+ if (timeout && !wdd->pretimeout) {
+ wdd->pretimeout = wdd->timeout / 2;
+ reg |= (WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN);
+ } else if (!timeout && wdd->pretimeout) {
+ wdd->pretimeout = 0;
+ reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN);
+ } else {
+ return 0;
+ }
+
+ reg |= WDT_MODE_KEY;
+ iowrite32(reg, wdt_base + WDT_MODE);
+
+ return mtk_wdt_set_timeout(wdd, wdd->timeout);
+}
+
+static irqreturn_t mtk_wdt_isr(int irq, void *arg)
+{
+ struct watchdog_device *wdd = arg;
+
+ watchdog_notify_pretimeout(wdd);
+
+ return IRQ_HANDLED;
+}
+
+static const struct watchdog_info mtk_wdt_info = {
+ .identity = DRV_NAME,
+ .options = WDIOF_SETTIMEOUT |
+ WDIOF_KEEPALIVEPING |
+ WDIOF_MAGICCLOSE,
+};
+
+static const struct watchdog_info mtk_wdt_pt_info = {
+ .identity = DRV_NAME,
+ .options = WDIOF_SETTIMEOUT |
+ WDIOF_PRETIMEOUT |
+ WDIOF_KEEPALIVEPING |
+ WDIOF_MAGICCLOSE,
+};
+
+static const struct watchdog_ops mtk_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = mtk_wdt_start,
+ .stop = mtk_wdt_stop,
+ .ping = mtk_wdt_ping,
+ .set_timeout = mtk_wdt_set_timeout,
+ .set_pretimeout = mtk_wdt_set_pretimeout,
+ .restart = mtk_wdt_restart,
+};
+
+static int mtk_wdt_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct mtk_wdt_dev *mtk_wdt;
+ const struct mtk_wdt_data *wdt_data;
+ int err, irq;
+
+ mtk_wdt = devm_kzalloc(dev, sizeof(*mtk_wdt), GFP_KERNEL);
+ if (!mtk_wdt)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, mtk_wdt);
+
+ mtk_wdt->wdt_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(mtk_wdt->wdt_base))
+ return PTR_ERR(mtk_wdt->wdt_base);
+
+ irq = platform_get_irq_optional(pdev, 0);
+ if (irq > 0) {
+ err = devm_request_irq(&pdev->dev, irq, mtk_wdt_isr, 0, "wdt_bark",
+ &mtk_wdt->wdt_dev);
+ if (err)
+ return err;
+
+ mtk_wdt->wdt_dev.info = &mtk_wdt_pt_info;
+ mtk_wdt->wdt_dev.pretimeout = WDT_MAX_TIMEOUT / 2;
+ } else {
+ if (irq == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+
+ mtk_wdt->wdt_dev.info = &mtk_wdt_info;
+ }
+
+ mtk_wdt->wdt_dev.ops = &mtk_wdt_ops;
+ mtk_wdt->wdt_dev.timeout = WDT_MAX_TIMEOUT;
+ mtk_wdt->wdt_dev.max_hw_heartbeat_ms = WDT_MAX_TIMEOUT * 1000;
+ mtk_wdt->wdt_dev.min_timeout = WDT_MIN_TIMEOUT;
+ mtk_wdt->wdt_dev.parent = dev;
+
+ watchdog_init_timeout(&mtk_wdt->wdt_dev, timeout, dev);
+ watchdog_set_nowayout(&mtk_wdt->wdt_dev, nowayout);
+ watchdog_set_restart_priority(&mtk_wdt->wdt_dev, 128);
+
+ watchdog_set_drvdata(&mtk_wdt->wdt_dev, mtk_wdt);
+
+ mtk_wdt_init(&mtk_wdt->wdt_dev);
+
+ watchdog_stop_on_reboot(&mtk_wdt->wdt_dev);
+ err = devm_watchdog_register_device(dev, &mtk_wdt->wdt_dev);
+ if (unlikely(err))
+ return err;
+
+ dev_info(dev, "Watchdog enabled (timeout=%d sec, nowayout=%d)\n",
+ mtk_wdt->wdt_dev.timeout, nowayout);
+
+ wdt_data = of_device_get_match_data(dev);
+ if (wdt_data) {
+ err = toprgu_register_reset_controller(pdev,
+ wdt_data->toprgu_sw_rst_num);
+ if (err)
+ return err;
+ }
+
+ mtk_wdt->disable_wdt_extrst =
+ of_property_read_bool(dev->of_node, "mediatek,disable-extrst");
+
+ return 0;
+}
+
+static int mtk_wdt_suspend(struct device *dev)
+{
+ struct mtk_wdt_dev *mtk_wdt = dev_get_drvdata(dev);
+
+ if (watchdog_active(&mtk_wdt->wdt_dev))
+ mtk_wdt_stop(&mtk_wdt->wdt_dev);
+
+ return 0;
+}
+
+static int mtk_wdt_resume(struct device *dev)
+{
+ struct mtk_wdt_dev *mtk_wdt = dev_get_drvdata(dev);
+
+ if (watchdog_active(&mtk_wdt->wdt_dev)) {
+ mtk_wdt_start(&mtk_wdt->wdt_dev);
+ mtk_wdt_ping(&mtk_wdt->wdt_dev);
+ }
+
+ return 0;
+}
+
+static const struct of_device_id mtk_wdt_dt_ids[] = {
+ { .compatible = "mediatek,mt2712-wdt", .data = &mt2712_data },
+ { .compatible = "mediatek,mt6589-wdt" },
+ { .compatible = "mediatek,mt7986-wdt", .data = &mt7986_data },
+ { .compatible = "mediatek,mt8183-wdt", .data = &mt8183_data },
+ { .compatible = "mediatek,mt8186-wdt", .data = &mt8186_data },
+ { .compatible = "mediatek,mt8192-wdt", .data = &mt8192_data },
+ { .compatible = "mediatek,mt8195-wdt", .data = &mt8195_data },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mtk_wdt_dt_ids);
+
+static DEFINE_SIMPLE_DEV_PM_OPS(mtk_wdt_pm_ops,
+ mtk_wdt_suspend, mtk_wdt_resume);
+
+static struct platform_driver mtk_wdt_driver = {
+ .probe = mtk_wdt_probe,
+ .driver = {
+ .name = DRV_NAME,
+ .pm = pm_sleep_ptr(&mtk_wdt_pm_ops),
+ .of_match_table = mtk_wdt_dt_ids,
+ },
+};
+
+module_platform_driver(mtk_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("Matthias Brugger <matthias.bgg@gmail.com>");
+MODULE_DESCRIPTION("Mediatek WatchDog Timer Driver");
+MODULE_VERSION(DRV_VERSION);