summaryrefslogtreecommitdiffstats
path: root/drivers/watchdog/txx9wdt.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/watchdog/txx9wdt.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/watchdog/txx9wdt.c')
-rw-r--r--drivers/watchdog/txx9wdt.c173
1 files changed, 173 insertions, 0 deletions
diff --git a/drivers/watchdog/txx9wdt.c b/drivers/watchdog/txx9wdt.c
new file mode 100644
index 0000000000..89a54b6645
--- /dev/null
+++ b/drivers/watchdog/txx9wdt.c
@@ -0,0 +1,173 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * txx9wdt: A Hardware Watchdog Driver for TXx9 SoCs
+ *
+ * Copyright (C) 2007 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <asm/txx9tmr.h>
+
+#define WD_TIMER_CCD 7 /* 1/256 */
+#define WD_TIMER_CLK (clk_get_rate(txx9_imclk) / (2 << WD_TIMER_CCD))
+#define WD_MAX_TIMEOUT ((0xffffffff >> (32 - TXX9_TIMER_BITS)) / WD_TIMER_CLK)
+#define TIMER_MARGIN 60 /* Default is 60 seconds */
+
+static unsigned int timeout = TIMER_MARGIN; /* in seconds */
+module_param(timeout, uint, 0);
+MODULE_PARM_DESC(timeout,
+ "Watchdog timeout in seconds. "
+ "(0<timeout<((2^" __MODULE_STRING(TXX9_TIMER_BITS) ")/(IMCLK/256)), "
+ "default=" __MODULE_STRING(TIMER_MARGIN) ")");
+
+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 struct txx9_tmr_reg __iomem *txx9wdt_reg;
+static struct clk *txx9_imclk;
+static DEFINE_SPINLOCK(txx9_lock);
+
+static int txx9wdt_ping(struct watchdog_device *wdt_dev)
+{
+ spin_lock(&txx9_lock);
+ __raw_writel(TXx9_TMWTMR_TWIE | TXx9_TMWTMR_TWC, &txx9wdt_reg->wtmr);
+ spin_unlock(&txx9_lock);
+ return 0;
+}
+
+static int txx9wdt_start(struct watchdog_device *wdt_dev)
+{
+ spin_lock(&txx9_lock);
+ __raw_writel(WD_TIMER_CLK * wdt_dev->timeout, &txx9wdt_reg->cpra);
+ __raw_writel(WD_TIMER_CCD, &txx9wdt_reg->ccdr);
+ __raw_writel(0, &txx9wdt_reg->tisr); /* clear pending interrupt */
+ __raw_writel(TXx9_TMTCR_TCE | TXx9_TMTCR_CCDE | TXx9_TMTCR_TMODE_WDOG,
+ &txx9wdt_reg->tcr);
+ __raw_writel(TXx9_TMWTMR_TWIE | TXx9_TMWTMR_TWC, &txx9wdt_reg->wtmr);
+ spin_unlock(&txx9_lock);
+ return 0;
+}
+
+static int txx9wdt_stop(struct watchdog_device *wdt_dev)
+{
+ spin_lock(&txx9_lock);
+ __raw_writel(TXx9_TMWTMR_WDIS, &txx9wdt_reg->wtmr);
+ __raw_writel(__raw_readl(&txx9wdt_reg->tcr) & ~TXx9_TMTCR_TCE,
+ &txx9wdt_reg->tcr);
+ spin_unlock(&txx9_lock);
+ return 0;
+}
+
+static int txx9wdt_set_timeout(struct watchdog_device *wdt_dev,
+ unsigned int new_timeout)
+{
+ wdt_dev->timeout = new_timeout;
+ txx9wdt_stop(wdt_dev);
+ txx9wdt_start(wdt_dev);
+ return 0;
+}
+
+static const struct watchdog_info txx9wdt_info = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+ .identity = "Hardware Watchdog for TXx9",
+};
+
+static const struct watchdog_ops txx9wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = txx9wdt_start,
+ .stop = txx9wdt_stop,
+ .ping = txx9wdt_ping,
+ .set_timeout = txx9wdt_set_timeout,
+};
+
+static struct watchdog_device txx9wdt = {
+ .info = &txx9wdt_info,
+ .ops = &txx9wdt_ops,
+};
+
+static int __init txx9wdt_probe(struct platform_device *dev)
+{
+ int ret;
+
+ txx9_imclk = clk_get(NULL, "imbus_clk");
+ if (IS_ERR(txx9_imclk)) {
+ ret = PTR_ERR(txx9_imclk);
+ txx9_imclk = NULL;
+ goto exit;
+ }
+ ret = clk_prepare_enable(txx9_imclk);
+ if (ret) {
+ clk_put(txx9_imclk);
+ txx9_imclk = NULL;
+ goto exit;
+ }
+
+ txx9wdt_reg = devm_platform_ioremap_resource(dev, 0);
+ if (IS_ERR(txx9wdt_reg)) {
+ ret = PTR_ERR(txx9wdt_reg);
+ goto exit;
+ }
+
+ if (timeout < 1 || timeout > WD_MAX_TIMEOUT)
+ timeout = TIMER_MARGIN;
+ txx9wdt.timeout = timeout;
+ txx9wdt.min_timeout = 1;
+ txx9wdt.max_timeout = WD_MAX_TIMEOUT;
+ txx9wdt.parent = &dev->dev;
+ watchdog_set_nowayout(&txx9wdt, nowayout);
+
+ ret = watchdog_register_device(&txx9wdt);
+ if (ret)
+ goto exit;
+
+ pr_info("Hardware Watchdog Timer: timeout=%d sec (max %ld) (nowayout= %d)\n",
+ timeout, WD_MAX_TIMEOUT, nowayout);
+
+ return 0;
+exit:
+ if (txx9_imclk) {
+ clk_disable_unprepare(txx9_imclk);
+ clk_put(txx9_imclk);
+ }
+ return ret;
+}
+
+static int __exit txx9wdt_remove(struct platform_device *dev)
+{
+ watchdog_unregister_device(&txx9wdt);
+ clk_disable_unprepare(txx9_imclk);
+ clk_put(txx9_imclk);
+ return 0;
+}
+
+static void txx9wdt_shutdown(struct platform_device *dev)
+{
+ txx9wdt_stop(&txx9wdt);
+}
+
+static struct platform_driver txx9wdt_driver = {
+ .remove = __exit_p(txx9wdt_remove),
+ .shutdown = txx9wdt_shutdown,
+ .driver = {
+ .name = "txx9wdt",
+ },
+};
+
+module_platform_driver_probe(txx9wdt_driver, txx9wdt_probe);
+
+MODULE_DESCRIPTION("TXx9 Watchdog Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:txx9wdt");