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Release 4.16 drivers/watchdog/hpwdt.c

Directory: drivers/watchdog
/*
 *      HPE WatchDog Driver
 *      based on
 *
 *      SoftDog 0.05:   A Software Watchdog Device
 *
 *      (c) Copyright 2015 Hewlett Packard Enterprise Development LP
 *      Thomas Mingarelli <thomas.mingarelli@hpe.com>
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      version 2 as published by the Free Software Foundation
 *
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/device.h>
#include <linux/fs.h>
#include <linux/io.h>
#include <linux/bitops.h>
#include <linux/kernel.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>
#include <linux/types.h>
#include <linux/uaccess.h>
#include <linux/watchdog.h>
#include <asm/nmi.h>


#define HPWDT_VERSION			"1.4.0"

#define SECS_TO_TICKS(secs)		((secs) * 1000 / 128)

#define TICKS_TO_SECS(ticks)		((ticks) * 128 / 1000)

#define HPWDT_MAX_TIMER			TICKS_TO_SECS(65535)

#define DEFAULT_MARGIN			30


static unsigned int soft_margin = DEFAULT_MARGIN;	
/* in seconds */

static unsigned int reload;			
/* the computed soft_margin */

static bool nowayout = WATCHDOG_NOWAYOUT;
#ifdef CONFIG_HPWDT_NMI_DECODING

static unsigned int allow_kdump = 1;
#endif

static char expect_release;

static unsigned long hpwdt_is_open;


static void __iomem *pci_mem_addr;		
/* the PCI-memory address */

static unsigned long __iomem *hpwdt_nmistat;

static unsigned long __iomem *hpwdt_timer_reg;

static unsigned long __iomem *hpwdt_timer_con;


static const struct pci_device_id hpwdt_devices[] = {
	{ PCI_DEVICE(PCI_VENDOR_ID_COMPAQ, 0xB203) },	/* iLO2 */
	{ PCI_DEVICE(PCI_VENDOR_ID_HP, 0x3306) },	/* iLO3 */
	{0},			/* terminate list */
};
MODULE_DEVICE_TABLE(pci, hpwdt_devices);


/*
 *      Watchdog operations
 */

static void hpwdt_start(void) { reload = SECS_TO_TICKS(soft_margin); iowrite16(reload, hpwdt_timer_reg); iowrite8(0x85, hpwdt_timer_con); }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli2689.66%266.67%
dann frazier310.34%133.33%
Total29100.00%3100.00%


static void hpwdt_stop(void) { unsigned long data; data = ioread8(hpwdt_timer_con); data &= 0xFE; iowrite8(data, hpwdt_timer_con); }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli30100.00%2100.00%
Total30100.00%2100.00%


static void hpwdt_ping(void) { iowrite16(reload, hpwdt_timer_reg); }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli15100.00%1100.00%
Total15100.00%1100.00%


static int hpwdt_change_timer(int new_margin) { if (new_margin < 1 || new_margin > HPWDT_MAX_TIMER) { pr_warn("New value passed in is invalid: %d seconds\n", new_margin); return -EINVAL; } soft_margin = new_margin; pr_debug("New timer passed in is %d seconds\n", new_margin); reload = SECS_TO_TICKS(soft_margin); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli4483.02%125.00%
dann frazier59.43%250.00%
Joe Perches47.55%125.00%
Total53100.00%4100.00%


static int hpwdt_time_left(void) { return TICKS_TO_SECS(ioread16(hpwdt_timer_reg)); }

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dann frazier17100.00%1100.00%
Total17100.00%1100.00%

#ifdef CONFIG_HPWDT_NMI_DECODING
static int hpwdt_my_nmi(void) { return ioread8(hpwdt_nmistat) & 0x6; }

Contributors

PersonTokensPropCommitsCommitProp
Jerry Hoemann16100.00%1100.00%
Total16100.00%1100.00%

/* * NMI Handler */
static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs) { if ((ulReason == NMI_UNKNOWN) && !hpwdt_my_nmi()) return NMI_DONE; if (allow_kdump) hpwdt_stop(); nmi_panic(regs, "An NMI occurred. Depending on your system the reason " "for the NMI is logged in any one of the following " "resources:\n" "1. Integrated Management Log (IML)\n" "2. OA Syslog\n" "3. OA Forward Progress Log\n" "4. iLO Event Log"); return NMI_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli2750.94%342.86%
Jerry Hoemann1833.96%228.57%
Hidehiro Kawai47.55%114.29%
Don Zickus47.55%114.29%
Total53100.00%7100.00%

#endif /* CONFIG_HPWDT_NMI_DECODING */ /* * /dev/watchdog handling */
static int hpwdt_open(struct inode *inode, struct file *file) { /* /dev/watchdog can only be opened once */ if (test_and_set_bit(0, &hpwdt_is_open)) return -EBUSY; /* Start the watchdog */ hpwdt_start(); hpwdt_ping(); return nonseekable_open(inode, file); }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli46100.00%1100.00%
Total46100.00%1100.00%


static int hpwdt_release(struct inode *inode, struct file *file) { /* Stop the watchdog */ if (expect_release == 42) { hpwdt_stop(); } else { pr_crit("Unexpected close, not stopping watchdog!\n"); hpwdt_ping(); } expect_release = 0; /* /dev/watchdog is being closed, make sure it can be re-opened */ clear_bit(0, &hpwdt_is_open); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli5396.36%150.00%
Joe Perches23.64%150.00%
Total55100.00%2100.00%


static ssize_t hpwdt_write(struct file *file, const char __user *data, size_t len, loff_t *ppos) { /* See if we got the magic character 'V' and reload the timer */ if (len) { if (!nowayout) { size_t i; /* note: just in case someone wrote the magic character * five months ago... */ expect_release = 0; /* scan to see whether or not we got the magic char. */ for (i = 0; i != len; i++) { char c; if (get_user(c, data + i)) return -EFAULT; if (c == 'V') expect_release = 42; } } /* someone wrote to us, we should reload the timer */ hpwdt_ping(); } return len; }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli97100.00%1100.00%
Total97100.00%1100.00%

static const struct watchdog_info ident = { .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, .identity = "HPE iLO2+ HW Watchdog Timer", };
static long hpwdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { void __user *argp = (void __user *)arg; int __user *p = argp; int new_margin, options; int ret = -ENOTTY; switch (cmd) { case WDIOC_GETSUPPORT: ret = 0; if (copy_to_user(argp, &ident, sizeof(ident))) ret = -EFAULT; break; case WDIOC_GETSTATUS: case WDIOC_GETBOOTSTATUS: ret = put_user(0, p); break; case WDIOC_KEEPALIVE: hpwdt_ping(); ret = 0; break; case WDIOC_SETOPTIONS: ret = get_user(options, p); if (ret) break; if (options & WDIOS_DISABLECARD) hpwdt_stop(); if (options & WDIOS_ENABLECARD) { hpwdt_start(); hpwdt_ping(); } break; case WDIOC_SETTIMEOUT: ret = get_user(new_margin, p); if (ret) break; ret = hpwdt_change_timer(new_margin); if (ret) break; hpwdt_ping(); /* Fall */ case WDIOC_GETTIMEOUT: ret = put_user(soft_margin, p); break; case WDIOC_GETTIMELEFT: ret = put_user(hpwdt_time_left(), p); break; } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli15773.36%133.33%
Jean Delvare4320.09%133.33%
dann frazier146.54%133.33%
Total214100.00%3100.00%

/* * Kernel interfaces */ static const struct file_operations hpwdt_fops = { .owner = THIS_MODULE, .llseek = no_llseek, .write = hpwdt_write, .unlocked_ioctl = hpwdt_ioctl, .open = hpwdt_open, .release = hpwdt_release, }; static struct miscdevice hpwdt_miscdev = { .minor = WATCHDOG_MINOR, .name = "watchdog", .fops = &hpwdt_fops, }; /* * Init & Exit */
static int hpwdt_init_nmi_decoding(struct pci_dev *dev) { #ifdef CONFIG_HPWDT_NMI_DECODING int retval; /* * Only one function can register for NMI_UNKNOWN */ retval = register_nmi_handler(NMI_UNKNOWN, hpwdt_pretimeout, 0, "hpwdt"); if (retval) goto error; retval = register_nmi_handler(NMI_SERR, hpwdt_pretimeout, 0, "hpwdt"); if (retval) goto error1; retval = register_nmi_handler(NMI_IO_CHECK, hpwdt_pretimeout, 0, "hpwdt"); if (retval) goto error2; dev_info(&dev->dev, "HPE Watchdog Timer Driver: NMI decoding initialized" ", allow kernel dump: %s (default = 1/ON)\n", (allow_kdump == 0) ? "OFF" : "ON"); return 0; error2: unregister_nmi_handler(NMI_SERR, "hpwdt"); error1: unregister_nmi_handler(NMI_UNKNOWN, "hpwdt"); error: dev_warn(&dev->dev, "Unable to register a die notifier (err=%d).\n", retval); return retval; #endif /* CONFIG_HPWDT_NMI_DECODING */ return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Don Zickus7653.15%342.86%
dann frazier5639.16%114.29%
Jerry Hoemann96.29%114.29%
Masanari Iida10.70%114.29%
Thomas Mingarelli10.70%114.29%
Total143100.00%7100.00%


static void hpwdt_exit_nmi_decoding(void) { #ifdef CONFIG_HPWDT_NMI_DECODING unregister_nmi_handler(NMI_UNKNOWN, "hpwdt"); unregister_nmi_handler(NMI_SERR, "hpwdt"); unregister_nmi_handler(NMI_IO_CHECK, "hpwdt"); #endif }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli1441.18%120.00%
dann frazier1235.29%240.00%
Jerry Hoemann411.76%120.00%
Don Zickus411.76%120.00%
Total34100.00%5100.00%


static int hpwdt_init_one(struct pci_dev *dev, const struct pci_device_id *ent) { int retval; /* * First let's find out if we are on an iLO2+ server. We will * not run on a legacy ASM box. * So we only support the G5 ProLiant servers and higher. */ if (dev->subsystem_vendor != PCI_VENDOR_ID_HP && dev->subsystem_vendor != PCI_VENDOR_ID_HP_3PAR) { dev_warn(&dev->dev, "This server does not have an iLO2+ ASIC.\n"); return -ENODEV; } /* * Ignore all auxilary iLO devices with the following PCI ID */ if (dev->subsystem_vendor == PCI_VENDOR_ID_HP && dev->subsystem_device == 0x1979) return -ENODEV; if (pci_enable_device(dev)) { dev_warn(&dev->dev, "Not possible to enable PCI Device: 0x%x:0x%x.\n", ent->vendor, ent->device); return -ENODEV; } pci_mem_addr = pci_iomap(dev, 1, 0x80); if (!pci_mem_addr) { dev_warn(&dev->dev, "Unable to detect the iLO2+ server memory.\n"); retval = -ENOMEM; goto error_pci_iomap; } hpwdt_nmistat = pci_mem_addr + 0x6e; hpwdt_timer_reg = pci_mem_addr + 0x70; hpwdt_timer_con = pci_mem_addr + 0x72; /* Make sure that timer is disabled until /dev/watchdog is opened */ hpwdt_stop(); /* Make sure that we have a valid soft_margin */ if (hpwdt_change_timer(soft_margin)) hpwdt_change_timer(DEFAULT_MARGIN); /* Initialize NMI Decoding functionality */ retval = hpwdt_init_nmi_decoding(dev); if (retval != 0) goto error_init_nmi_decoding; retval = misc_register(&hpwdt_miscdev); if (retval < 0) { dev_warn(&dev->dev, "Unable to register miscdev on minor=%d (err=%d).\n", WATCHDOG_MINOR, retval); goto error_misc_register; } dev_info(&dev->dev, "HPE Watchdog Timer Driver: %s" ", timer margin: %d seconds (nowayout=%d).\n", HPWDT_VERSION, soft_margin, nowayout); return 0; error_misc_register: hpwdt_exit_nmi_decoding(); error_init_nmi_decoding: pci_iounmap(dev, pci_mem_addr); error_pci_iomap: pci_disable_device(dev); return retval; }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli22885.71%444.44%
dann frazier166.02%222.22%
Brian Boylston124.51%111.11%
Jerry Hoemann62.26%111.11%
Toshi Kani41.50%111.11%
Total266100.00%9100.00%


static void hpwdt_exit(struct pci_dev *dev) { if (!nowayout) hpwdt_stop(); misc_deregister(&hpwdt_miscdev); hpwdt_exit_nmi_decoding(); pci_iounmap(dev, pci_mem_addr); pci_disable_device(dev); }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli3895.00%150.00%
dann frazier25.00%150.00%
Total40100.00%2100.00%

static struct pci_driver hpwdt_driver = { .name = "hpwdt", .id_table = hpwdt_devices, .probe = hpwdt_init_one, .remove = hpwdt_exit, }; MODULE_AUTHOR("Tom Mingarelli"); MODULE_DESCRIPTION("hp watchdog driver"); MODULE_LICENSE("GPL"); MODULE_VERSION(HPWDT_VERSION); module_param(soft_margin, int, 0); MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds"); module_param(nowayout, bool, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); #ifdef CONFIG_HPWDT_NMI_DECODING module_param(allow_kdump, int, 0); MODULE_PARM_DESC(allow_kdump, "Start a kernel dump after NMI occurs"); #endif /* CONFIG_HPWDT_NMI_DECODING */ module_pci_driver(hpwdt_driver);

Overall Contributors

PersonTokensPropCommitsCommitProp
Thomas Mingarelli100066.67%1026.32%
dann frazier20013.33%923.68%
Jerry Hoemann1218.07%25.26%
Don Zickus845.60%37.89%
Jean Delvare453.00%25.26%
Brian Boylston130.87%12.63%
Joe Perches130.87%12.63%
Wim Van Sebroeck60.40%410.53%
Toshi Kani40.27%12.63%
Hidehiro Kawai40.27%12.63%
Ingo Molnar30.20%12.63%
Arnd Bergmann30.20%12.63%
Bernhard Walle30.20%12.63%
Masanari Iida10.07%12.63%
Total1500100.00%38100.00%
Directory: drivers/watchdog
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