[PATCH 7/7] watchdog: Remove BCM63XX_WDT
Guenter Roeck
linux at roeck-us.net
Thu Oct 28 11:20:05 PDT 2021
On Thu, Oct 28, 2021 at 10:23:22AM -0700, Florian Fainelli wrote:
> Now that we can utilize the BCM7038_WDT driver, remove that one which
> was not converted to the watchdog APIs. There are a couple of notable
> differences with how the bcm7038_wdt driver proceeds:
>
> - bcm63xx_wdt would register with the ad-hoc BCM63xx hardware timer API,
> but this would only be used in order to catch the interrupt *before* a
> SoC reset and make the kernel "die"
>
> - bcm6xx_wdt would register a software timer and kick it every second in
> order to pet the watchdog, thus offering a two step watchdog process.
> This is not something that is brought over to the bcm7038_wdt as it is
> deemed unnecessary. If user-space cannot pet the watchdog, but a
> kernel timer can, the system is still in a bad shape anyway.
>
> bcm7038_wdt is simpler in its behavior and behaves as a standard
> watchdog driver and is not making use of any specific platform APIs,
> therefore making it more maintainable and extensible.
>
> Signed-off-by: Florian Fainelli <f.fainelli at gmail.com>
Reviewed-by: Guenter Roeck <linux at roeck-us.net>
> ---
> drivers/watchdog/Kconfig | 10 --
> drivers/watchdog/Makefile | 1 -
> drivers/watchdog/bcm63xx_wdt.c | 315 ---------------------------------
> 3 files changed, 326 deletions(-)
> delete mode 100644 drivers/watchdog/bcm63xx_wdt.c
>
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index 24a775dd2bf1..acebf9caf6d1 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -1709,16 +1709,6 @@ config OCTEON_WDT
> from the first interrupt, it is then only poked when the
> device is written.
>
> -config BCM63XX_WDT
> - tristate "Broadcom BCM63xx hardware watchdog"
> - depends on BCM63XX
> - help
> - Watchdog driver for the built in watchdog hardware in Broadcom
> - BCM63xx SoC.
> -
> - To compile this driver as a loadable module, choose M here.
> - The module will be called bcm63xx_wdt.
> -
> config BCM2835_WDT
> tristate "Broadcom BCM2835 hardware watchdog"
> depends on ARCH_BCM2835 || (OF && COMPILE_TEST)
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index 1bd2d6f37c53..9811c4b1cd16 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -154,7 +154,6 @@ obj-$(CONFIG_XILINX_WATCHDOG) += of_xilinx_wdt.o
> # MIPS Architecture
> obj-$(CONFIG_ATH79_WDT) += ath79_wdt.o
> obj-$(CONFIG_BCM47XX_WDT) += bcm47xx_wdt.o
> -obj-$(CONFIG_BCM63XX_WDT) += bcm63xx_wdt.o
> obj-$(CONFIG_RC32434_WDT) += rc32434_wdt.o
> obj-$(CONFIG_INDYDOG) += indydog.o
> obj-$(CONFIG_JZ4740_WDT) += jz4740_wdt.o
> diff --git a/drivers/watchdog/bcm63xx_wdt.c b/drivers/watchdog/bcm63xx_wdt.c
> deleted file mode 100644
> index 7cdb25363ea0..000000000000
> --- a/drivers/watchdog/bcm63xx_wdt.c
> +++ /dev/null
> @@ -1,315 +0,0 @@
> -// SPDX-License-Identifier: GPL-2.0+
> -/*
> - * Broadcom BCM63xx SoC watchdog driver
> - *
> - * Copyright (C) 2007, Miguel Gaio <miguel.gaio at efixo.com>
> - * Copyright (C) 2008, Florian Fainelli <florian at openwrt.org>
> - *
> - */
> -
> -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> -
> -#include <linux/bitops.h>
> -#include <linux/errno.h>
> -#include <linux/fs.h>
> -#include <linux/io.h>
> -#include <linux/kernel.h>
> -#include <linux/miscdevice.h>
> -#include <linux/module.h>
> -#include <linux/moduleparam.h>
> -#include <linux/types.h>
> -#include <linux/uaccess.h>
> -#include <linux/watchdog.h>
> -#include <linux/timer.h>
> -#include <linux/jiffies.h>
> -#include <linux/interrupt.h>
> -#include <linux/ptrace.h>
> -#include <linux/resource.h>
> -#include <linux/platform_device.h>
> -
> -#include <bcm63xx_cpu.h>
> -#include <bcm63xx_io.h>
> -#include <bcm63xx_regs.h>
> -#include <bcm63xx_timer.h>
> -
> -#define PFX KBUILD_MODNAME
> -
> -#define WDT_HZ 50000000 /* Fclk */
> -#define WDT_DEFAULT_TIME 30 /* seconds */
> -#define WDT_MAX_TIME 256 /* seconds */
> -
> -static struct {
> - void __iomem *regs;
> - struct timer_list timer;
> - unsigned long inuse;
> - atomic_t ticks;
> -} bcm63xx_wdt_device;
> -
> -static int expect_close;
> -
> -static int wdt_time = WDT_DEFAULT_TIME;
> -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) ")");
> -
> -/* HW functions */
> -static void bcm63xx_wdt_hw_start(void)
> -{
> - bcm_writel(0xfffffffe, bcm63xx_wdt_device.regs + WDT_DEFVAL_REG);
> - bcm_writel(WDT_START_1, bcm63xx_wdt_device.regs + WDT_CTL_REG);
> - bcm_writel(WDT_START_2, bcm63xx_wdt_device.regs + WDT_CTL_REG);
> -}
> -
> -static void bcm63xx_wdt_hw_stop(void)
> -{
> - bcm_writel(WDT_STOP_1, bcm63xx_wdt_device.regs + WDT_CTL_REG);
> - bcm_writel(WDT_STOP_2, bcm63xx_wdt_device.regs + WDT_CTL_REG);
> -}
> -
> -static void bcm63xx_wdt_isr(void *data)
> -{
> - struct pt_regs *regs = get_irq_regs();
> -
> - die(PFX " fire", regs);
> -}
> -
> -static void bcm63xx_timer_tick(struct timer_list *unused)
> -{
> - if (!atomic_dec_and_test(&bcm63xx_wdt_device.ticks)) {
> - bcm63xx_wdt_hw_start();
> - mod_timer(&bcm63xx_wdt_device.timer, jiffies + HZ);
> - } else
> - pr_crit("watchdog will restart system\n");
> -}
> -
> -static void bcm63xx_wdt_pet(void)
> -{
> - atomic_set(&bcm63xx_wdt_device.ticks, wdt_time);
> -}
> -
> -static void bcm63xx_wdt_start(void)
> -{
> - bcm63xx_wdt_pet();
> - bcm63xx_timer_tick(0);
> -}
> -
> -static void bcm63xx_wdt_pause(void)
> -{
> - del_timer_sync(&bcm63xx_wdt_device.timer);
> - bcm63xx_wdt_hw_stop();
> -}
> -
> -static int bcm63xx_wdt_settimeout(int new_time)
> -{
> - if ((new_time <= 0) || (new_time > WDT_MAX_TIME))
> - return -EINVAL;
> -
> - wdt_time = new_time;
> -
> - return 0;
> -}
> -
> -static int bcm63xx_wdt_open(struct inode *inode, struct file *file)
> -{
> - if (test_and_set_bit(0, &bcm63xx_wdt_device.inuse))
> - return -EBUSY;
> -
> - bcm63xx_wdt_start();
> - return stream_open(inode, file);
> -}
> -
> -static int bcm63xx_wdt_release(struct inode *inode, struct file *file)
> -{
> - if (expect_close == 42)
> - bcm63xx_wdt_pause();
> - else {
> - pr_crit("Unexpected close, not stopping watchdog!\n");
> - bcm63xx_wdt_start();
> - }
> - clear_bit(0, &bcm63xx_wdt_device.inuse);
> - expect_close = 0;
> - return 0;
> -}
> -
> -static ssize_t bcm63xx_wdt_write(struct file *file, const char *data,
> - size_t len, loff_t *ppos)
> -{
> - if (len) {
> - if (!nowayout) {
> - size_t i;
> -
> - /* In case it was set long ago */
> - expect_close = 0;
> -
> - for (i = 0; i != len; i++) {
> - char c;
> - if (get_user(c, data + i))
> - return -EFAULT;
> - if (c == 'V')
> - expect_close = 42;
> - }
> - }
> - bcm63xx_wdt_pet();
> - }
> - return len;
> -}
> -
> -static struct watchdog_info bcm63xx_wdt_info = {
> - .identity = PFX,
> - .options = WDIOF_SETTIMEOUT |
> - WDIOF_KEEPALIVEPING |
> - WDIOF_MAGICCLOSE,
> -};
> -
> -
> -static long bcm63xx_wdt_ioctl(struct file *file, unsigned int cmd,
> - unsigned long arg)
> -{
> - void __user *argp = (void __user *)arg;
> - int __user *p = argp;
> - int new_value, retval = -EINVAL;
> -
> - switch (cmd) {
> - case WDIOC_GETSUPPORT:
> - return copy_to_user(argp, &bcm63xx_wdt_info,
> - sizeof(bcm63xx_wdt_info)) ? -EFAULT : 0;
> -
> - case WDIOC_GETSTATUS:
> - case WDIOC_GETBOOTSTATUS:
> - return put_user(0, p);
> -
> - case WDIOC_SETOPTIONS:
> - if (get_user(new_value, p))
> - return -EFAULT;
> -
> - if (new_value & WDIOS_DISABLECARD) {
> - bcm63xx_wdt_pause();
> - retval = 0;
> - }
> - if (new_value & WDIOS_ENABLECARD) {
> - bcm63xx_wdt_start();
> - retval = 0;
> - }
> -
> - return retval;
> -
> - case WDIOC_KEEPALIVE:
> - bcm63xx_wdt_pet();
> - return 0;
> -
> - case WDIOC_SETTIMEOUT:
> - if (get_user(new_value, p))
> - return -EFAULT;
> -
> - if (bcm63xx_wdt_settimeout(new_value))
> - return -EINVAL;
> -
> - bcm63xx_wdt_pet();
> -
> - case WDIOC_GETTIMEOUT:
> - return put_user(wdt_time, p);
> -
> - default:
> - return -ENOTTY;
> -
> - }
> -}
> -
> -static const struct file_operations bcm63xx_wdt_fops = {
> - .owner = THIS_MODULE,
> - .llseek = no_llseek,
> - .write = bcm63xx_wdt_write,
> - .unlocked_ioctl = bcm63xx_wdt_ioctl,
> - .compat_ioctl = compat_ptr_ioctl,
> - .open = bcm63xx_wdt_open,
> - .release = bcm63xx_wdt_release,
> -};
> -
> -static struct miscdevice bcm63xx_wdt_miscdev = {
> - .minor = WATCHDOG_MINOR,
> - .name = "watchdog",
> - .fops = &bcm63xx_wdt_fops,
> -};
> -
> -
> -static int bcm63xx_wdt_probe(struct platform_device *pdev)
> -{
> - int ret;
> - struct resource *r;
> -
> - timer_setup(&bcm63xx_wdt_device.timer, bcm63xx_timer_tick, 0);
> -
> - r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> - if (!r) {
> - dev_err(&pdev->dev, "failed to get resources\n");
> - return -ENODEV;
> - }
> -
> - bcm63xx_wdt_device.regs = devm_ioremap(&pdev->dev, r->start,
> - resource_size(r));
> - if (!bcm63xx_wdt_device.regs) {
> - dev_err(&pdev->dev, "failed to remap I/O resources\n");
> - return -ENXIO;
> - }
> -
> - ret = bcm63xx_timer_register(TIMER_WDT_ID, bcm63xx_wdt_isr, NULL);
> - if (ret < 0) {
> - dev_err(&pdev->dev, "failed to register wdt timer isr\n");
> - return ret;
> - }
> -
> - if (bcm63xx_wdt_settimeout(wdt_time)) {
> - bcm63xx_wdt_settimeout(WDT_DEFAULT_TIME);
> - dev_info(&pdev->dev,
> - ": wdt_time value must be 1 <= wdt_time <= 256, using %d\n",
> - wdt_time);
> - }
> -
> - ret = misc_register(&bcm63xx_wdt_miscdev);
> - if (ret < 0) {
> - dev_err(&pdev->dev, "failed to register watchdog device\n");
> - goto unregister_timer;
> - }
> -
> - dev_info(&pdev->dev, " started, timer margin: %d sec\n",
> - WDT_DEFAULT_TIME);
> -
> - return 0;
> -
> -unregister_timer:
> - bcm63xx_timer_unregister(TIMER_WDT_ID);
> - return ret;
> -}
> -
> -static int bcm63xx_wdt_remove(struct platform_device *pdev)
> -{
> - if (!nowayout)
> - bcm63xx_wdt_pause();
> -
> - misc_deregister(&bcm63xx_wdt_miscdev);
> - bcm63xx_timer_unregister(TIMER_WDT_ID);
> - return 0;
> -}
> -
> -static void bcm63xx_wdt_shutdown(struct platform_device *pdev)
> -{
> - bcm63xx_wdt_pause();
> -}
> -
> -static struct platform_driver bcm63xx_wdt_driver = {
> - .probe = bcm63xx_wdt_probe,
> - .remove = bcm63xx_wdt_remove,
> - .shutdown = bcm63xx_wdt_shutdown,
> - .driver = {
> - .name = "bcm63xx-wdt",
> - }
> -};
> -
> -module_platform_driver(bcm63xx_wdt_driver);
> -
> -MODULE_AUTHOR("Miguel Gaio <miguel.gaio at efixo.com>");
> -MODULE_AUTHOR("Florian Fainelli <florian at openwrt.org>");
> -MODULE_DESCRIPTION("Driver for the Broadcom BCM63xx SoC watchdog");
> -MODULE_LICENSE("GPL");
> -MODULE_ALIAS("platform:bcm63xx-wdt");
> --
> 2.25.1
>
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