linux/drivers/watchdog/hpwdt.c
Jerry Hoemann 093d43858d watchdog: hpwdt: Claim NMI from iLO
The hwpdt driver is overloaded for handling both the iLO
watchdog and the explicit "Generate NMI to System" virutal
button.  Hence NMI handler needs to claim NMI resulting
from the virutal button.

Claim if iLO generated accommodating firmware that might
set wrong bit.

Signed-off-by: Jerry Hoemann <jerry.hoemann@hpe.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2018-10-02 13:32:21 +02:00

377 lines
8.7 KiB
C

/*
* 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 && !mynmi)
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,
.pretimeout = PRETIMEOUT_SEC,
};
/*
* 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.pretimeout = pretimeout ? PRETIMEOUT_SEC : 0;
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);