[PATCH 06/22] watchdog: remove the shwdt driver

Christoph Hellwig
2023-01-13T06:27:30Z

Now that arch/sh is removed this driver is dead code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
.../watchdog/watchdog-parameters.rst | 12 -
drivers/watchdog/Kconfig | 20 -
drivers/watchdog/Makefile | 3 -
drivers/watchdog/shwdt.c | 344 ------------------
4 files changed, 379 deletions(-)
delete mode 100644 drivers/watchdog/shwdt.c

diff --git a/Documentation/watchdog/watchdog-parameters.rst b/Documentation/watchdog/watchdog-parameters.rst
index 29153eed668900..553ac2f8ae23f7 100644
--- a/Documentation/watchdog/watchdog-parameters.rst
+++ b/Documentation/watchdog/watchdog-parameters.rst
@@ -579,18 +579,6 @@ scx200_wdt:

-------------------------------------------------

-shwdt:
- clock_division_ratio:
- Clock division ratio. Valid ranges are from 0x5 (1.31ms)
- to 0x7 (5.25ms). (default=7)
- heartbeat:
- Watchdog heartbeat in seconds. (1 <= heartbeat <= 3600, default=30
- nowayout:
- Watchdog cannot be stopped once started
- (default=kernel config parameter)
-
--------------------------------------------------
-
smsc37b787_wdt:
timeout:
range is 1-255 units, default is 60
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 0bc40b763b0652..7db0a5e636cf65 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -2015,26 +2015,6 @@ config DIAG288_WATCHDOG
To compile this driver as a module, choose M here. The module
will be called diag288_wdt.

-# SUPERH (sh + sh64) Architecture
-
-config SH_WDT
- tristate "SuperH Watchdog"
- depends on SUPERH && (CPU_SH3 || CPU_SH4 || COMPILE_TEST)
- select WATCHDOG_CORE
- help
- This driver adds watchdog support for the integrated watchdog in the
- SuperH processors. If you have one of these processors and wish
- to have watchdog support enabled, say Y, otherwise say N.
-
- As a side note, saying Y here will automatically boost HZ to 1000
- so that the timer has a chance to clear the overflow counter. On
- slower systems (such as the SH-2 and SH-3) this will likely yield
- some performance issues. As such, the WDT should be avoided here
- unless it is absolutely necessary.
-
- To compile this driver as a module, choose M here: the
- module will be called shwdt.
-
# SPARC Architecture

# SPARC64 Architecture
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 9cbf6580f16c9f..a852ab4d7176ac 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -195,9 +195,6 @@ obj-$(CONFIG_WATCHDOG_RTAS) += wdrtas.o
# S390 Architecture
obj-$(CONFIG_DIAG288_WATCHDOG) += diag288_wdt.o

-# SUPERH (sh + sh64) Architecture
-obj-$(CONFIG_SH_WDT) += shwdt.o
-
# SPARC Architecture

# SPARC64 Architecture
diff --git a/drivers/watchdog/shwdt.c b/drivers/watchdog/shwdt.c
deleted file mode 100644
index f55533e0e0454e..00000000000000
--- a/drivers/watchdog/shwdt.c
+++ /dev/null
@@ -1,344 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * drivers/watchdog/shwdt.c
- *
- * Watchdog driver for integrated watchdog in the SuperH processors.
- *
- * Copyright (C) 2001 - 2012 Paul Mundt <lethal@linux-sh.org>
- *
- * 14-Dec-2001 Matt Domsch <Matt_Domsch@dell.com>
- * Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT
- *
- * 19-Apr-2002 Rob Radez <rob@osinvestor.com>
- * Added expect close support, made emulated timeout runtime changeable
- * general cleanups, add some ioctls
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/platform_device.h>
-#include <linux/init.h>
-#include <linux/types.h>
-#include <linux/spinlock.h>
-#include <linux/watchdog.h>
-#include <linux/pm_runtime.h>
-#include <linux/fs.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include <linux/io.h>
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <asm/watchdog.h>
-
-#define DRV_NAME "sh-wdt"
-
-/*
- * Default clock division ratio is 5.25 msecs. For an additional table of
- * values, consult the asm-sh/watchdog.h. Overload this at module load
- * time.
- *
- * In order for this to work reliably we need to have HZ set to 1000 or
- * something quite higher than 100 (or we need a proper high-res timer
- * implementation that will deal with this properly), otherwise the 10ms
- * resolution of a jiffy is enough to trigger the overflow. For things like
- * the SH-4 and SH-5, this isn't necessarily that big of a problem, though
- * for the SH-2 and SH-3, this isn't recommended unless the WDT is absolutely
- * necssary.
- *
- * As a result of this timing problem, the only modes that are particularly
- * feasible are the 4096 and the 2048 divisors, which yield 5.25 and 2.62ms
- * overflow periods respectively.
- *
- * Also, since we can't really expect userspace to be responsive enough
- * before the overflow happens, we maintain two separate timers .. One in
- * the kernel for clearing out WOVF every 2ms or so (again, this depends on
- * HZ == 1000), and another for monitoring userspace writes to the WDT device.
- *
- * As such, we currently use a configurable heartbeat interval which defaults
- * to 30s. In this case, the userspace daemon is only responsible for periodic
- * writes to the device before the next heartbeat is scheduled. If the daemon
- * misses its deadline, the kernel timer will allow the WDT to overflow.
- */
-static int clock_division_ratio = WTCSR_CKS_4096;
-#define next_ping_period(cks) (jiffies + msecs_to_jiffies(cks - 4))
-
-#define WATCHDOG_HEARTBEAT 30 /* 30 sec default heartbeat */
-static int heartbeat = WATCHDOG_HEARTBEAT; /* in seconds */
-static bool nowayout = WATCHDOG_NOWAYOUT;
-static unsigned long next_heartbeat;
-
-struct sh_wdt {
- void __iomem *base;
- struct device *dev;
- struct clk *clk;
- spinlock_t lock;
-
- struct timer_list timer;
-};
-
-static int sh_wdt_start(struct watchdog_device *wdt_dev)
-{
- struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev);
- unsigned long flags;
- u8 csr;
-
- pm_runtime_get_sync(wdt->dev);
- clk_enable(wdt->clk);
-
- spin_lock_irqsave(&wdt->lock, flags);
-
- next_heartbeat = jiffies + (heartbeat * HZ);
- mod_timer(&wdt->timer, next_ping_period(clock_division_ratio));
-
- csr = sh_wdt_read_csr();
- csr |= WTCSR_WT | clock_division_ratio;
- sh_wdt_write_csr(csr);
-
- sh_wdt_write_cnt(0);
-
- /*
- * These processors have a bit of an inconsistent initialization
- * process.. starting with SH-3, RSTS was moved to WTCSR, and the
- * RSTCSR register was removed.
- *
- * On the SH-2 however, in addition with bits being in different
- * locations, we must deal with RSTCSR outright..
- */
- csr = sh_wdt_read_csr();
- csr |= WTCSR_TME;
- csr &= ~WTCSR_RSTS;
- sh_wdt_write_csr(csr);
-
-#ifdef CONFIG_CPU_SH2
- csr = sh_wdt_read_rstcsr();
- csr &= ~RSTCSR_RSTS;
- sh_wdt_write_rstcsr(csr);
-#endif
- spin_unlock_irqrestore(&wdt->lock, flags);
-
- return 0;
-}
-
-static int sh_wdt_stop(struct watchdog_device *wdt_dev)
-{
- struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev);
- unsigned long flags;
- u8 csr;
-
- spin_lock_irqsave(&wdt->lock, flags);
-
- del_timer(&wdt->timer);
-
- csr = sh_wdt_read_csr();
- csr &= ~WTCSR_TME;
- sh_wdt_write_csr(csr);
-
- spin_unlock_irqrestore(&wdt->lock, flags);
-
- clk_disable(wdt->clk);
- pm_runtime_put_sync(wdt->dev);
-
- return 0;
-}
-
-static int sh_wdt_keepalive(struct watchdog_device *wdt_dev)
-{
- struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev);
- unsigned long flags;
-
- spin_lock_irqsave(&wdt->lock, flags);
- next_heartbeat = jiffies + (heartbeat * HZ);
- spin_unlock_irqrestore(&wdt->lock, flags);
-
- return 0;
-}
-
-static int sh_wdt_set_heartbeat(struct watchdog_device *wdt_dev, unsigned t)
-{
- struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev);
- unsigned long flags;
-
- if (unlikely(t < 1 || t > 3600)) /* arbitrary upper limit */
- return -EINVAL;
-
- spin_lock_irqsave(&wdt->lock, flags);
- heartbeat = t;
- wdt_dev->timeout = t;
- spin_unlock_irqrestore(&wdt->lock, flags);
-
- return 0;
-}
-
-static void sh_wdt_ping(struct timer_list *t)
-{
- struct sh_wdt *wdt = from_timer(wdt, t, timer);
- unsigned long flags;
-
- spin_lock_irqsave(&wdt->lock, flags);
- if (time_before(jiffies, next_heartbeat)) {
- u8 csr;
-
- csr = sh_wdt_read_csr();
- csr &= ~WTCSR_IOVF;
- sh_wdt_write_csr(csr);
-
- sh_wdt_write_cnt(0);
-
- mod_timer(&wdt->timer, next_ping_period(clock_division_ratio));
- } else
- dev_warn(wdt->dev, "Heartbeat lost! Will not ping "
- "the watchdog\n");
- spin_unlock_irqrestore(&wdt->lock, flags);
-}
-
-static const struct watchdog_info sh_wdt_info = {
- .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT |
- WDIOF_MAGICCLOSE,
- .firmware_version = 1,
- .identity = "SH WDT",
-};
-
-static const struct watchdog_ops sh_wdt_ops = {
- .owner = THIS_MODULE,
- .start = sh_wdt_start,
- .stop = sh_wdt_stop,
- .ping = sh_wdt_keepalive,
- .set_timeout = sh_wdt_set_heartbeat,
-};
-
-static struct watchdog_device sh_wdt_dev = {
- .info = &sh_wdt_info,
- .ops = &sh_wdt_ops,
-};
-
-static int sh_wdt_probe(struct platform_device *pdev)
-{
- struct sh_wdt *wdt;
- int rc;
-
- /*
- * As this driver only covers the global watchdog case, reject
- * any attempts to register per-CPU watchdogs.
- */
- if (pdev->id != -1)
- return -EINVAL;
-
- wdt = devm_kzalloc(&pdev->dev, sizeof(struct sh_wdt), GFP_KERNEL);
- if (unlikely(!wdt))
- return -ENOMEM;
-
- wdt->dev = &pdev->dev;
-
- wdt->clk = devm_clk_get(&pdev->dev, NULL);
- if (IS_ERR(wdt->clk)) {
- /*
- * Clock framework support is optional, continue on
- * anyways if we don't find a matching clock.
- */
- wdt->clk = NULL;
- }
-
- wdt->base = devm_platform_ioremap_resource(pdev, 0);
- if (IS_ERR(wdt->base))
- return PTR_ERR(wdt->base);
-
- watchdog_set_nowayout(&sh_wdt_dev, nowayout);
- watchdog_set_drvdata(&sh_wdt_dev, wdt);
- sh_wdt_dev.parent = &pdev->dev;
-
- spin_lock_init(&wdt->lock);
-
- rc = sh_wdt_set_heartbeat(&sh_wdt_dev, heartbeat);
- if (unlikely(rc)) {
- /* Default timeout if invalid */
- sh_wdt_set_heartbeat(&sh_wdt_dev, WATCHDOG_HEARTBEAT);
-
- dev_warn(&pdev->dev,
- "heartbeat value must be 1<=x<=3600, using %d\n",
- sh_wdt_dev.timeout);
- }
-
- dev_info(&pdev->dev, "configured with heartbeat=%d sec (nowayout=%d)\n",
- sh_wdt_dev.timeout, nowayout);
-
- rc = watchdog_register_device(&sh_wdt_dev);
- if (unlikely(rc)) {
- dev_err(&pdev->dev, "Can't register watchdog (err=%d)\n", rc);
- return rc;
- }
-
- timer_setup(&wdt->timer, sh_wdt_ping, 0);
- wdt->timer.expires = next_ping_period(clock_division_ratio);
-
- dev_info(&pdev->dev, "initialized.\n");
-
- pm_runtime_enable(&pdev->dev);
-
- return 0;
-}
-
-static int sh_wdt_remove(struct platform_device *pdev)
-{
- watchdog_unregister_device(&sh_wdt_dev);
-
- pm_runtime_disable(&pdev->dev);
-
- return 0;
-}
-
-static void sh_wdt_shutdown(struct platform_device *pdev)
-{
- sh_wdt_stop(&sh_wdt_dev);
-}
-
-static struct platform_driver sh_wdt_driver = {
- .driver = {
- .name = DRV_NAME,
- },
-
- .probe = sh_wdt_probe,
- .remove = sh_wdt_remove,
- .shutdown = sh_wdt_shutdown,
-};
-
-static int __init sh_wdt_init(void)
-{
- if (unlikely(clock_division_ratio < 0x5 ||
- clock_division_ratio > 0x7)) {
- clock_division_ratio = WTCSR_CKS_4096;
-
- pr_info("divisor must be 0x5<=x<=0x7, using %d\n",
- clock_division_ratio);
- }
-
- return platform_driver_register(&sh_wdt_driver);
-}
-
-static void __exit sh_wdt_exit(void)
-{
- platform_driver_unregister(&sh_wdt_driver);
-}
-module_init(sh_wdt_init);
-module_exit(sh_wdt_exit);
-
-MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
-MODULE_DESCRIPTION("SuperH watchdog driver");
-MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:" DRV_NAME);
-
-module_param(clock_division_ratio, int, 0);
-MODULE_PARM_DESC(clock_division_ratio,
- "Clock division ratio. Valid ranges are from 0x5 (1.31ms) "
- "to 0x7 (5.25ms). (default=" __MODULE_STRING(WTCSR_CKS_4096) ")");
-
-module_param(heartbeat, int, 0);
-MODULE_PARM_DESC(heartbeat,
- "Watchdog heartbeat in seconds. (1 <= heartbeat <= 3600, default="
- __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
-
-module_param(nowayout, bool, 0);
-MODULE_PARM_DESC(nowayout,
- "Watchdog cannot be stopped once started (default="
- __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
--
2.39.0