/*
* HPE WatchDog Driver
* based on
*
* SoftDog 0.05: A Software Watchdog Device
*
* (c) Copyright 2018 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/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>
#include <linux/types.h>
#include <linux/watchdog.h>
#include <asm/nmi.h>
#define HPWDT_VERSION "2.0.0"
#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
#define PRETIMEOUT_SEC 9
static bool ilo5;
static unsigned int soft_margin = DEFAULT_MARGIN; /* in seconds */
static bool nowayout = WATCHDOG_NOWAYOUT;
static bool pretimeout = IS_ENABLED(CONFIG_HPWDT_NMI_DECODING);
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 int hpwdt_start(struct watchdog_device *wdd)
{
int control = 0x81 | (pretimeout ? 0x4 : 0);
int reload = SECS_TO_TICKS(wdd->timeout);
dev_dbg(wdd->parent, "start watchdog 0x%08x:0x%02x\n", reload, control);
iowrite16(reload, hpwdt_timer_reg);
iowrite8(control, hpwdt_timer_con);
return 0;
}
static void hpwdt_stop(void)
{
unsigned long data;
pr_debug("stop watchdog\n");
data = ioread8(hpwdt_timer_con);
data &= 0xFE;
iowrite8(data, hpwdt_timer_con);
}
static int hpwdt_stop_core(struct watchdog_device *wdd)
{
hpwdt_stop();
return 0;
}
static int hpwdt_ping(struct watchdog_device *wdd)
{
int reload = SECS_TO_TICKS(wdd->timeout);
dev_dbg(wdd->parent, "ping watchdog 0x%08x\n", reload);
iowrite16(reload, hpwdt_timer_reg);
return 0;
}
static unsigned int hpwdt_gettimeleft(struct watchdog_device *wdd)
{
return TICKS_TO_SECS(ioread16(hpwdt_timer_reg));
}
static int hpwdt_settimeout(struct watchdog_device *wdd, unsigned int val)
{
dev_dbg(wdd->parent, "set_timeout = %d\n", val);
wdd->timeout = val;
if (val <= wdd->pretimeout) {
dev_dbg(wdd->parent, "pretimeout < timeout. Setting to zero\n");
wdd->pretimeout = 0;
pretimeout = 0;
if (watchdog_active(wdd))
hpwdt_start(wdd);
}
hpwdt_ping(wdd);
return 0;
}
#ifdef CONFIG_HPWDT_NMI_DECODING
static int hpwdt_set_pretimeout(struct watchdog_device *wdd, unsigned int req)
{
unsigned int val = 0;
dev_dbg(wdd->parent, "set_pretimeout = %d\n", req);
if (req) {
val = PRETIMEOUT_SEC;
if (val >= wdd->timeout)
return -EINVAL;
}
if (val != req)
dev_dbg(wdd->parent, "Rounding pretimeout to: %d\n", val);
wdd->pretimeout = val;
pretimeout = !!val;
if (watchdog_active(wdd))
hpwdt_start(wdd);
return 0;
}
static int hpwdt_my_nmi(void)
{
return ioread8(hpwdt_nmistat) & 0x6;
}
/*
* NMI Handler
*/
static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)
{
unsigned int mynmi = hpwdt_my_nmi();
static char panic_msg[] =
"00: 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";
if (ilo5 && ulReason == NMI_UNKNOWN && !mynmi)
return NMI_DONE;
if (ilo5 && !pretimeout)
return NMI_DONE;
hpwdt_stop();
hex_byte_pack(panic_msg, mynmi);
nmi_panic(regs, panic_msg);
return NMI_HANDLED;
}
#endif /* CONFIG_HPWDT_NMI_DECODING */
static const struct watchdog_info ident = {
.options = WDIOF_PRETIMEOUT |
WDIOF_SETTIMEOUT |
WDIOF_KEEPALIVEPING |
WDIOF_MAGICCLOSE,
.identity = "HPE iLO2+ HW Watchdog Timer",
};
/*
* Kernel interfaces
*/
static const struct watchdog_ops hpwdt_ops = {
.owner = THIS_MODULE,
.start = hpwdt_start,
.stop = hpwdt_stop_core,
.ping = hpwdt_ping,
.set_timeout = hpwdt_settimeout,
.get_timeleft = hpwdt_gettimeleft,
#ifdef CONFIG_HPWDT_NMI_DECODING
.set_pretimeout = hpwdt_set_pretimeout,
#endif
};
static struct watchdog_device hpwdt_dev = {
.info = &ident,
.ops = &hpwdt_ops,
.min_timeout = 1,
.max_timeout = HPWDT_MAX_TIMER,
.timeout = DEFAULT_MARGIN,
#ifdef CONFIG_HPWDT_NMI_DECODING
.pretimeout = PRETIMEOUT_SEC,
#endif
};
/*
* 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\n");
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;
}
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
}
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();
/* Initialize NMI Decoding functionality */
retval = hpwdt_init_nmi_decoding(dev);
if (retval != 0)
goto error_init_nmi_decoding;
watchdog_set_nowayout(&hpwdt_dev, nowayout);
if (watchdog_init_timeout(&hpwdt_dev, soft_margin, NULL))
dev_warn(&dev->dev, "Invalid soft_margin: %d.\n", soft_margin);
hpwdt_dev.parent = &dev->dev;
retval = watchdog_register_device(&hpwdt_dev);
if (retval < 0) {
dev_err(&dev->dev, "watchdog register failed: %d.\n", retval);
goto error_wd_register;
}
dev_info(&dev->dev, "HPE Watchdog Timer Driver: %s"
", timer margin: %d seconds (nowayout=%d).\n",
HPWDT_VERSION, hpwdt_dev.timeout, nowayout);
if (dev->subsystem_vendor == PCI_VENDOR_ID_HP_3PAR)
ilo5 = true;
return 0;
error_wd_register:
hpwdt_exit_nmi_decoding();
error_init_nmi_decoding:
pci_iounmap(dev, pci_mem_addr);
error_pci_iomap:
pci_disable_device(dev);
return retval;
}
static void hpwdt_exit(struct pci_dev *dev)
{
if (!nowayout)
hpwdt_stop();
watchdog_unregister_device(&hpwdt_dev);
hpwdt_exit_nmi_decoding();
pci_iounmap(dev, pci_mem_addr);
pci_disable_device(dev);
}
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("hpe 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(pretimeout, bool, 0);
MODULE_PARM_DESC(pretimeout, "Watchdog pretimeout enabled");
#endif
module_pci_driver(hpwdt_driver);
