linux/drivers/watchdog/iTCO_vendor_support.c
Guenter Roeck d017327893 watchdog: convert remaining drivers to use SPDX license identifier
This gets rid of the unnecessary license boilerplate, and avoids
having to deal with individual patches one by one.

No functional changes.

Reviewed-by: Jerry Hoemann <jerry.hoemann@hpe.com>
Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-07-08 20:35:11 +02:00

215 lines
6.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* intel TCO vendor specific watchdog driver support
*
* (c) Copyright 2006-2009 Wim Van Sebroeck <wim@iguana.be>.
*
* Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
* provide warranty for any of this software. This material is
* provided "AS-IS" and at no charge.
*/
/*
* Includes, defines, variables, module parameters, ...
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
/* Module and version information */
#define DRV_NAME "iTCO_vendor_support"
#define DRV_VERSION "1.04"
/* Includes */
#include <linux/module.h> /* For module specific items */
#include <linux/moduleparam.h> /* For new moduleparam's */
#include <linux/types.h> /* For standard types (like size_t) */
#include <linux/errno.h> /* For the -ENODEV/... values */
#include <linux/kernel.h> /* For printk/panic/... */
#include <linux/init.h> /* For __init/__exit/... */
#include <linux/ioport.h> /* For io-port access */
#include <linux/io.h> /* For inb/outb/... */
#include "iTCO_vendor.h"
/* List of vendor support modes */
/* SuperMicro Pentium 3 Era 370SSE+-OEM1/P3TSSE */
#define SUPERMICRO_OLD_BOARD 1
/* SuperMicro Pentium 4 / Xeon 4 / EMT64T Era Systems - no longer supported */
#define SUPERMICRO_NEW_BOARD 2
/* Broken BIOS */
#define BROKEN_BIOS 911
static int vendorsupport;
module_param(vendorsupport, int, 0);
MODULE_PARM_DESC(vendorsupport, "iTCO vendor specific support mode, default="
"0 (none), 1=SuperMicro Pent3, 911=Broken SMI BIOS");
/*
* Vendor Specific Support
*/
/*
* Vendor Support: 1
* Board: Super Micro Computer Inc. 370SSE+-OEM1/P3TSSE
* iTCO chipset: ICH2
*
* Code contributed by: R. Seretny <lkpatches@paypc.com>
* Documentation obtained by R. Seretny from SuperMicro Technical Support
*
* To enable Watchdog function:
* BIOS setup -> Power -> TCO Logic SMI Enable -> Within5Minutes
* This setting enables SMI to clear the watchdog expired flag.
* If BIOS or CPU fail which may cause SMI hang, then system will
* reboot. When application starts to use watchdog function,
* application has to take over the control from SMI.
*
* For P3TSSE, J36 jumper needs to be removed to enable the Watchdog
* function.
*
* Note: The system will reboot when Expire Flag is set TWICE.
* So, if the watchdog timer is 20 seconds, then the maximum hang
* time is about 40 seconds, and the minimum hang time is about
* 20.6 seconds.
*/
static void supermicro_old_pre_start(struct resource *smires)
{
unsigned long val32;
/* Bit 13: TCO_EN -> 0 = Disables TCO logic generating an SMI# */
val32 = inl(smires->start);
val32 &= 0xffffdfff; /* Turn off SMI clearing watchdog */
outl(val32, smires->start); /* Needed to activate watchdog */
}
static void supermicro_old_pre_stop(struct resource *smires)
{
unsigned long val32;
/* Bit 13: TCO_EN -> 1 = Enables the TCO logic to generate SMI# */
val32 = inl(smires->start);
val32 |= 0x00002000; /* Turn on SMI clearing watchdog */
outl(val32, smires->start); /* Needed to deactivate watchdog */
}
/*
* Vendor Support: 911
* Board: Some Intel ICHx based motherboards
* iTCO chipset: ICH7+
*
* Some Intel motherboards have a broken BIOS implementation: i.e.
* the SMI handler clear's the TIMEOUT bit in the TC01_STS register
* and does not reload the time. Thus the TCO watchdog does not reboot
* the system.
*
* These are the conclusions of Andriy Gapon <avg@icyb.net.ua> after
* debugging: the SMI handler is quite simple - it tests value in
* TCO1_CNT against 0x800, i.e. checks TCO_TMR_HLT. If the bit is set
* the handler goes into an infinite loop, apparently to allow the
* second timeout and reboot. Otherwise it simply clears TIMEOUT bit
* in TCO1_STS and that's it.
* So the logic seems to be reversed, because it is hard to see how
* TIMEOUT can get set to 1 and SMI generated when TCO_TMR_HLT is set
* (other than a transitional effect).
*
* The only fix found to get the motherboard(s) to reboot is to put
* the glb_smi_en bit to 0. This is a dirty hack that bypasses the
* broken code by disabling Global SMI.
*
* WARNING: globally disabling SMI could possibly lead to dramatic
* problems, especially on laptops! I.e. various ACPI things where
* SMI is used for communication between OS and firmware.
*
* Don't use this fix if you don't need to!!!
*/
static void broken_bios_start(struct resource *smires)
{
unsigned long val32;
val32 = inl(smires->start);
/* Bit 13: TCO_EN -> 0 = Disables TCO logic generating an SMI#
Bit 0: GBL_SMI_EN -> 0 = No SMI# will be generated by ICH. */
val32 &= 0xffffdffe;
outl(val32, smires->start);
}
static void broken_bios_stop(struct resource *smires)
{
unsigned long val32;
val32 = inl(smires->start);
/* Bit 13: TCO_EN -> 1 = Enables TCO logic generating an SMI#
Bit 0: GBL_SMI_EN -> 1 = Turn global SMI on again. */
val32 |= 0x00002001;
outl(val32, smires->start);
}
/*
* Generic Support Functions
*/
void iTCO_vendor_pre_start(struct resource *smires,
unsigned int heartbeat)
{
switch (vendorsupport) {
case SUPERMICRO_OLD_BOARD:
supermicro_old_pre_start(smires);
break;
case BROKEN_BIOS:
broken_bios_start(smires);
break;
}
}
EXPORT_SYMBOL(iTCO_vendor_pre_start);
void iTCO_vendor_pre_stop(struct resource *smires)
{
switch (vendorsupport) {
case SUPERMICRO_OLD_BOARD:
supermicro_old_pre_stop(smires);
break;
case BROKEN_BIOS:
broken_bios_stop(smires);
break;
}
}
EXPORT_SYMBOL(iTCO_vendor_pre_stop);
int iTCO_vendor_check_noreboot_on(void)
{
switch (vendorsupport) {
case SUPERMICRO_OLD_BOARD:
return 0;
default:
return 1;
}
}
EXPORT_SYMBOL(iTCO_vendor_check_noreboot_on);
static int __init iTCO_vendor_init_module(void)
{
if (vendorsupport == SUPERMICRO_NEW_BOARD) {
pr_warn("Option vendorsupport=%d is no longer supported, "
"please use the w83627hf_wdt driver instead\n",
SUPERMICRO_NEW_BOARD);
return -EINVAL;
}
pr_info("vendor-support=%d\n", vendorsupport);
return 0;
}
static void __exit iTCO_vendor_exit_module(void)
{
pr_info("Module Unloaded\n");
}
module_init(iTCO_vendor_init_module);
module_exit(iTCO_vendor_exit_module);
MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>, "
"R. Seretny <lkpatches@paypc.com>");
MODULE_DESCRIPTION("Intel TCO Vendor Specific WatchDog Timer Driver Support");
MODULE_VERSION(DRV_VERSION);
MODULE_LICENSE("GPL");