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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/meson_gxbb_wdt.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/watchdog/meson_gxbb_wdt.c')
-rw-r--r--drivers/watchdog/meson_gxbb_wdt.c231
1 files changed, 231 insertions, 0 deletions
diff --git a/drivers/watchdog/meson_gxbb_wdt.c b/drivers/watchdog/meson_gxbb_wdt.c
new file mode 100644
index 000000000..981a2f7c3
--- /dev/null
+++ b/drivers/watchdog/meson_gxbb_wdt.c
@@ -0,0 +1,231 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+/*
+ * Copyright (c) 2016 BayLibre, SAS.
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ *
+ */
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+
+#define DEFAULT_TIMEOUT 30 /* seconds */
+
+#define GXBB_WDT_CTRL_REG 0x0
+#define GXBB_WDT_TCNT_REG 0x8
+#define GXBB_WDT_RSET_REG 0xc
+
+#define GXBB_WDT_CTRL_CLKDIV_EN BIT(25)
+#define GXBB_WDT_CTRL_CLK_EN BIT(24)
+#define GXBB_WDT_CTRL_EE_RESET BIT(21)
+#define GXBB_WDT_CTRL_EN BIT(18)
+#define GXBB_WDT_CTRL_DIV_MASK (BIT(18) - 1)
+
+#define GXBB_WDT_TCNT_SETUP_MASK (BIT(16) - 1)
+#define GXBB_WDT_TCNT_CNT_SHIFT 16
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started default="
+ __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+static unsigned int timeout;
+module_param(timeout, uint, 0);
+MODULE_PARM_DESC(timeout, "Watchdog heartbeat in seconds="
+ __MODULE_STRING(DEFAULT_TIMEOUT) ")");
+
+struct meson_gxbb_wdt {
+ void __iomem *reg_base;
+ struct watchdog_device wdt_dev;
+ struct clk *clk;
+};
+
+static int meson_gxbb_wdt_start(struct watchdog_device *wdt_dev)
+{
+ struct meson_gxbb_wdt *data = watchdog_get_drvdata(wdt_dev);
+
+ writel(readl(data->reg_base + GXBB_WDT_CTRL_REG) | GXBB_WDT_CTRL_EN,
+ data->reg_base + GXBB_WDT_CTRL_REG);
+
+ return 0;
+}
+
+static int meson_gxbb_wdt_stop(struct watchdog_device *wdt_dev)
+{
+ struct meson_gxbb_wdt *data = watchdog_get_drvdata(wdt_dev);
+
+ writel(readl(data->reg_base + GXBB_WDT_CTRL_REG) & ~GXBB_WDT_CTRL_EN,
+ data->reg_base + GXBB_WDT_CTRL_REG);
+
+ return 0;
+}
+
+static int meson_gxbb_wdt_ping(struct watchdog_device *wdt_dev)
+{
+ struct meson_gxbb_wdt *data = watchdog_get_drvdata(wdt_dev);
+
+ writel(0, data->reg_base + GXBB_WDT_RSET_REG);
+
+ return 0;
+}
+
+static int meson_gxbb_wdt_set_timeout(struct watchdog_device *wdt_dev,
+ unsigned int timeout)
+{
+ struct meson_gxbb_wdt *data = watchdog_get_drvdata(wdt_dev);
+ unsigned long tcnt = timeout * 1000;
+
+ if (tcnt > GXBB_WDT_TCNT_SETUP_MASK)
+ tcnt = GXBB_WDT_TCNT_SETUP_MASK;
+
+ wdt_dev->timeout = timeout;
+
+ meson_gxbb_wdt_ping(wdt_dev);
+
+ writel(tcnt, data->reg_base + GXBB_WDT_TCNT_REG);
+
+ return 0;
+}
+
+static unsigned int meson_gxbb_wdt_get_timeleft(struct watchdog_device *wdt_dev)
+{
+ struct meson_gxbb_wdt *data = watchdog_get_drvdata(wdt_dev);
+ unsigned long reg;
+
+ reg = readl(data->reg_base + GXBB_WDT_TCNT_REG);
+
+ return ((reg & GXBB_WDT_TCNT_SETUP_MASK) -
+ (reg >> GXBB_WDT_TCNT_CNT_SHIFT)) / 1000;
+}
+
+static const struct watchdog_ops meson_gxbb_wdt_ops = {
+ .start = meson_gxbb_wdt_start,
+ .stop = meson_gxbb_wdt_stop,
+ .ping = meson_gxbb_wdt_ping,
+ .set_timeout = meson_gxbb_wdt_set_timeout,
+ .get_timeleft = meson_gxbb_wdt_get_timeleft,
+};
+
+static const struct watchdog_info meson_gxbb_wdt_info = {
+ .identity = "Meson GXBB Watchdog",
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+};
+
+static int __maybe_unused meson_gxbb_wdt_resume(struct device *dev)
+{
+ struct meson_gxbb_wdt *data = dev_get_drvdata(dev);
+
+ if (watchdog_active(&data->wdt_dev))
+ meson_gxbb_wdt_start(&data->wdt_dev);
+
+ return 0;
+}
+
+static int __maybe_unused meson_gxbb_wdt_suspend(struct device *dev)
+{
+ struct meson_gxbb_wdt *data = dev_get_drvdata(dev);
+
+ if (watchdog_active(&data->wdt_dev))
+ meson_gxbb_wdt_stop(&data->wdt_dev);
+
+ return 0;
+}
+
+static const struct dev_pm_ops meson_gxbb_wdt_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(meson_gxbb_wdt_suspend, meson_gxbb_wdt_resume)
+};
+
+static const struct of_device_id meson_gxbb_wdt_dt_ids[] = {
+ { .compatible = "amlogic,meson-gxbb-wdt", },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, meson_gxbb_wdt_dt_ids);
+
+static void meson_clk_disable_unprepare(void *data)
+{
+ clk_disable_unprepare(data);
+}
+
+static int meson_gxbb_wdt_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct meson_gxbb_wdt *data;
+ int ret;
+ u32 ctrl_reg;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->reg_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(data->reg_base))
+ return PTR_ERR(data->reg_base);
+
+ data->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(data->clk))
+ return PTR_ERR(data->clk);
+
+ ret = clk_prepare_enable(data->clk);
+ if (ret)
+ return ret;
+ ret = devm_add_action_or_reset(dev, meson_clk_disable_unprepare,
+ data->clk);
+ if (ret)
+ return ret;
+
+ platform_set_drvdata(pdev, data);
+
+ data->wdt_dev.parent = dev;
+ data->wdt_dev.info = &meson_gxbb_wdt_info;
+ data->wdt_dev.ops = &meson_gxbb_wdt_ops;
+ data->wdt_dev.max_hw_heartbeat_ms = GXBB_WDT_TCNT_SETUP_MASK;
+ data->wdt_dev.min_timeout = 1;
+ data->wdt_dev.timeout = DEFAULT_TIMEOUT;
+ watchdog_init_timeout(&data->wdt_dev, timeout, dev);
+ watchdog_set_nowayout(&data->wdt_dev, nowayout);
+ watchdog_set_drvdata(&data->wdt_dev, data);
+
+ ctrl_reg = readl(data->reg_base + GXBB_WDT_CTRL_REG) &
+ GXBB_WDT_CTRL_EN;
+
+ if (ctrl_reg) {
+ /* Watchdog is running - keep it running but extend timeout
+ * to the maximum while setting the timebase
+ */
+ set_bit(WDOG_HW_RUNNING, &data->wdt_dev.status);
+ meson_gxbb_wdt_set_timeout(&data->wdt_dev,
+ GXBB_WDT_TCNT_SETUP_MASK / 1000);
+ }
+
+ /* Setup with 1ms timebase */
+ ctrl_reg |= ((clk_get_rate(data->clk) / 1000) &
+ GXBB_WDT_CTRL_DIV_MASK) |
+ GXBB_WDT_CTRL_EE_RESET |
+ GXBB_WDT_CTRL_CLK_EN |
+ GXBB_WDT_CTRL_CLKDIV_EN;
+
+ writel(ctrl_reg, data->reg_base + GXBB_WDT_CTRL_REG);
+ meson_gxbb_wdt_set_timeout(&data->wdt_dev, data->wdt_dev.timeout);
+
+ return devm_watchdog_register_device(dev, &data->wdt_dev);
+}
+
+static struct platform_driver meson_gxbb_wdt_driver = {
+ .probe = meson_gxbb_wdt_probe,
+ .driver = {
+ .name = "meson-gxbb-wdt",
+ .pm = &meson_gxbb_wdt_pm_ops,
+ .of_match_table = meson_gxbb_wdt_dt_ids,
+ },
+};
+
+module_platform_driver(meson_gxbb_wdt_driver);
+
+MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
+MODULE_DESCRIPTION("Amlogic Meson GXBB Watchdog timer driver");
+MODULE_LICENSE("Dual BSD/GPL");