2 * intel TCO vendor specific watchdog driver support
4 * (c) Copyright 2006-2009 Wim Van Sebroeck <wim@iguana.be>.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
11 * Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
12 * provide warranty for any of this software. This material is
13 * provided "AS-IS" and at no charge.
17 * Includes, defines, variables, module parameters, ...
20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22 /* Module and version information */
23 #define DRV_NAME "iTCO_vendor_support"
24 #define DRV_VERSION "1.04"
27 #include <linux/module.h> /* For module specific items */
28 #include <linux/moduleparam.h> /* For new moduleparam's */
29 #include <linux/types.h> /* For standard types (like size_t) */
30 #include <linux/errno.h> /* For the -ENODEV/... values */
31 #include <linux/kernel.h> /* For printk/panic/... */
32 #include <linux/init.h> /* For __init/__exit/... */
33 #include <linux/ioport.h> /* For io-port access */
34 #include <linux/io.h> /* For inb/outb/... */
36 #include "iTCO_vendor.h"
39 #define SMI_EN (acpibase + 0x30) /* SMI Control and Enable Register */
40 #define TCOBASE (acpibase + 0x60) /* TCO base address */
41 #define TCO1_STS (TCOBASE + 0x04) /* TCO1 Status Register */
43 /* List of vendor support modes */
44 /* SuperMicro Pentium 3 Era 370SSE+-OEM1/P3TSSE */
45 #define SUPERMICRO_OLD_BOARD 1
46 /* SuperMicro Pentium 4 / Xeon 4 / EMT64T Era Systems */
47 #define SUPERMICRO_NEW_BOARD 2
49 #define BROKEN_BIOS 911
51 static int vendorsupport;
52 module_param(vendorsupport, int, 0);
53 MODULE_PARM_DESC(vendorsupport, "iTCO vendor specific support mode, default="
54 "0 (none), 1=SuperMicro Pent3, 2=SuperMicro Pent4+, "
55 "911=Broken SMI BIOS");
58 * Vendor Specific Support
63 * Board: Super Micro Computer Inc. 370SSE+-OEM1/P3TSSE
66 * Code contributed by: R. Seretny <lkpatches@paypc.com>
67 * Documentation obtained by R. Seretny from SuperMicro Technical Support
69 * To enable Watchdog function:
70 * BIOS setup -> Power -> TCO Logic SMI Enable -> Within5Minutes
71 * This setting enables SMI to clear the watchdog expired flag.
72 * If BIOS or CPU fail which may cause SMI hang, then system will
73 * reboot. When application starts to use watchdog function,
74 * application has to take over the control from SMI.
76 * For P3TSSE, J36 jumper needs to be removed to enable the Watchdog
79 * Note: The system will reboot when Expire Flag is set TWICE.
80 * So, if the watchdog timer is 20 seconds, then the maximum hang
81 * time is about 40 seconds, and the minimum hang time is about
85 static void supermicro_old_pre_start(unsigned long acpibase)
89 /* Bit 13: TCO_EN -> 0 = Disables TCO logic generating an SMI# */
91 val32 &= 0xffffdfff; /* Turn off SMI clearing watchdog */
92 outl(val32, SMI_EN); /* Needed to activate watchdog */
95 static void supermicro_old_pre_stop(unsigned long acpibase)
99 /* Bit 13: TCO_EN -> 1 = Enables the TCO logic to generate SMI# */
101 val32 |= 0x00002000; /* Turn on SMI clearing watchdog */
102 outl(val32, SMI_EN); /* Needed to deactivate watchdog */
107 * Board: Super Micro Computer Inc. P4SBx, P4DPx
110 * Code contributed by: R. Seretny <lkpatches@paypc.com>
111 * Documentation obtained by R. Seretny from SuperMicro Technical Support
113 * To enable Watchdog function:
116 * BIOS setup -> Advanced -> Integrated Peripherals -> Watch Dog Feature
118 * BIOS setup -> Advanced -> I/O Device Configuration -> Watch Dog
119 * This setting enables or disables Watchdog function. When enabled, the
120 * default watchdog timer is set to be 5 minutes (about 4m35s). It is
121 * enough to load and run the OS. The application (service or driver) has
122 * to take over the control once OS is running up and before watchdog
128 * This jumper is used for safety. Closed is enabled. This jumper
129 * prevents user enables watchdog in BIOS by accident.
131 * To enable Watch Dog function, both BIOS and JUMPER must be enabled.
133 * The documentation lists motherboards P4SBx and P4DPx series as of
134 * 20-March-2002. However, this code works flawlessly with much newer
135 * motherboards, such as my X6DHR-8G2 (SuperServer 6014H-82).
137 * The original iTCO driver as written does not actually reset the
138 * watchdog timer on these machines, as a result they reboot after five
141 * NOTE: You may leave the Watchdog function disabled in the SuperMicro
142 * BIOS to avoid a "boot-race"... This driver will enable watchdog
143 * functionality even if it's disabled in the BIOS once the /dev/watchdog
148 #define SM_REGINDEX 0x2e /* SuperMicro ICH4+ Register Index */
149 #define SM_DATAIO 0x2f /* SuperMicro ICH4+ Register Data I/O */
151 /* Control Register's */
152 #define SM_CTLPAGESW 0x07 /* SuperMicro ICH4+ Control Page Switch */
153 #define SM_CTLPAGE 0x08 /* SuperMicro ICH4+ Control Page Num */
155 #define SM_WATCHENABLE 0x30 /* Watchdog enable: Bit 0: 0=off, 1=on */
157 #define SM_WATCHPAGE 0x87 /* Watchdog unlock control page */
159 #define SM_ENDWATCH 0xAA /* Watchdog lock control page */
161 #define SM_COUNTMODE 0xf5 /* Watchdog count mode select */
162 /* (Bit 3: 0 = seconds, 1 = minutes */
164 #define SM_WATCHTIMER 0xf6 /* 8-bits, Watchdog timer counter (RW) */
166 #define SM_RESETCONTROL 0xf7 /* Watchdog reset control */
167 /* Bit 6: timer is reset by kbd interrupt */
168 /* Bit 7: timer is reset by mouse interrupt */
170 static void supermicro_new_unlock_watchdog(void)
172 /* Write 0x87 to port 0x2e twice */
173 outb(SM_WATCHPAGE, SM_REGINDEX);
174 outb(SM_WATCHPAGE, SM_REGINDEX);
175 /* Switch to watchdog control page */
176 outb(SM_CTLPAGESW, SM_REGINDEX);
177 outb(SM_CTLPAGE, SM_DATAIO);
180 static void supermicro_new_lock_watchdog(void)
182 outb(SM_ENDWATCH, SM_REGINDEX);
185 static void supermicro_new_pre_start(unsigned int heartbeat)
189 supermicro_new_unlock_watchdog();
191 /* Watchdog timer setting needs to be in seconds*/
192 outb(SM_COUNTMODE, SM_REGINDEX);
193 val = inb(SM_DATAIO);
195 outb(val, SM_DATAIO);
197 /* Write heartbeat interval to WDOG */
198 outb(SM_WATCHTIMER, SM_REGINDEX);
199 outb((heartbeat & 255), SM_DATAIO);
201 /* Make sure keyboard/mouse interrupts don't interfere */
202 outb(SM_RESETCONTROL, SM_REGINDEX);
203 val = inb(SM_DATAIO);
205 outb(val, SM_DATAIO);
207 /* enable watchdog by setting bit 0 of Watchdog Enable to 1 */
208 outb(SM_WATCHENABLE, SM_REGINDEX);
209 val = inb(SM_DATAIO);
211 outb(val, SM_DATAIO);
213 supermicro_new_lock_watchdog();
216 static void supermicro_new_pre_stop(void)
220 supermicro_new_unlock_watchdog();
222 /* disable watchdog by setting bit 0 of Watchdog Enable to 0 */
223 outb(SM_WATCHENABLE, SM_REGINDEX);
224 val = inb(SM_DATAIO);
226 outb(val, SM_DATAIO);
228 supermicro_new_lock_watchdog();
231 static void supermicro_new_pre_set_heartbeat(unsigned int heartbeat)
233 supermicro_new_unlock_watchdog();
235 /* reset watchdog timeout to heartveat value */
236 outb(SM_WATCHTIMER, SM_REGINDEX);
237 outb((heartbeat & 255), SM_DATAIO);
239 supermicro_new_lock_watchdog();
243 * Vendor Support: 911
244 * Board: Some Intel ICHx based motherboards
245 * iTCO chipset: ICH7+
247 * Some Intel motherboards have a broken BIOS implementation: i.e.
248 * the SMI handler clear's the TIMEOUT bit in the TC01_STS register
249 * and does not reload the time. Thus the TCO watchdog does not reboot
252 * These are the conclusions of Andriy Gapon <avg@icyb.net.ua> after
253 * debugging: the SMI handler is quite simple - it tests value in
254 * TCO1_CNT against 0x800, i.e. checks TCO_TMR_HLT. If the bit is set
255 * the handler goes into an infinite loop, apparently to allow the
256 * second timeout and reboot. Otherwise it simply clears TIMEOUT bit
257 * in TCO1_STS and that's it.
258 * So the logic seems to be reversed, because it is hard to see how
259 * TIMEOUT can get set to 1 and SMI generated when TCO_TMR_HLT is set
260 * (other than a transitional effect).
262 * The only fix found to get the motherboard(s) to reboot is to put
263 * the glb_smi_en bit to 0. This is a dirty hack that bypasses the
264 * broken code by disabling Global SMI.
266 * WARNING: globally disabling SMI could possibly lead to dramatic
267 * problems, especially on laptops! I.e. various ACPI things where
268 * SMI is used for communication between OS and firmware.
270 * Don't use this fix if you don't need to!!!
273 static void broken_bios_start(unsigned long acpibase)
278 /* Bit 13: TCO_EN -> 0 = Disables TCO logic generating an SMI#
279 Bit 0: GBL_SMI_EN -> 0 = No SMI# will be generated by ICH. */
284 static void broken_bios_stop(unsigned long acpibase)
289 /* Bit 13: TCO_EN -> 1 = Enables TCO logic generating an SMI#
290 Bit 0: GBL_SMI_EN -> 1 = Turn global SMI on again. */
296 * Generic Support Functions
299 void iTCO_vendor_pre_start(unsigned long acpibase,
300 unsigned int heartbeat)
302 switch (vendorsupport) {
303 case SUPERMICRO_OLD_BOARD:
304 supermicro_old_pre_start(acpibase);
306 case SUPERMICRO_NEW_BOARD:
307 supermicro_new_pre_start(heartbeat);
310 broken_bios_start(acpibase);
314 EXPORT_SYMBOL(iTCO_vendor_pre_start);
316 void iTCO_vendor_pre_stop(unsigned long acpibase)
318 switch (vendorsupport) {
319 case SUPERMICRO_OLD_BOARD:
320 supermicro_old_pre_stop(acpibase);
322 case SUPERMICRO_NEW_BOARD:
323 supermicro_new_pre_stop();
326 broken_bios_stop(acpibase);
330 EXPORT_SYMBOL(iTCO_vendor_pre_stop);
332 void iTCO_vendor_pre_keepalive(unsigned long acpibase, unsigned int heartbeat)
334 if (vendorsupport == SUPERMICRO_NEW_BOARD)
335 supermicro_new_pre_set_heartbeat(heartbeat);
337 EXPORT_SYMBOL(iTCO_vendor_pre_keepalive);
339 void iTCO_vendor_pre_set_heartbeat(unsigned int heartbeat)
341 if (vendorsupport == SUPERMICRO_NEW_BOARD)
342 supermicro_new_pre_set_heartbeat(heartbeat);
344 EXPORT_SYMBOL(iTCO_vendor_pre_set_heartbeat);
346 int iTCO_vendor_check_noreboot_on(void)
348 switch (vendorsupport) {
349 case SUPERMICRO_OLD_BOARD:
355 EXPORT_SYMBOL(iTCO_vendor_check_noreboot_on);
357 static int __init iTCO_vendor_init_module(void)
359 pr_info("vendor-support=%d\n", vendorsupport);
363 static void __exit iTCO_vendor_exit_module(void)
365 pr_info("Module Unloaded\n");
368 module_init(iTCO_vendor_init_module);
369 module_exit(iTCO_vendor_exit_module);
371 MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>, "
372 "R. Seretny <lkpatches@paypc.com>");
373 MODULE_DESCRIPTION("Intel TCO Vendor Specific WatchDog Timer Driver Support");
374 MODULE_VERSION(DRV_VERSION);
375 MODULE_LICENSE("GPL");