drivers/watchdog/iTCO_vendor_support.c

   1 /*
   2  *      intel TCO vendor specific watchdog driver support
   3  *
   4  *      (c) Copyright 2006-2009 Wim Van Sebroeck <wim@iguana.be>.
   5  *
   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.
  10  *
  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.
  14  */
  15
  16 /*
  17  *      Includes, defines, variables, module parameters, ...
  18  */
  19
  20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  21
  22 /* Module and version information */
  23 #define DRV_NAME        "iTCO_vendor_support"
  24 #define DRV_VERSION     "1.04"
  25
  26 /* Includes */
  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/... */
  35
  36 #include "iTCO_vendor.h"
  37
  38 /* List of vendor support modes */
  39 /* SuperMicro Pentium 3 Era 370SSE+-OEM1/P3TSSE */
  40 #define SUPERMICRO_OLD_BOARD    1
  41 /* SuperMicro Pentium 4 / Xeon 4 / EMT64T Era Systems */
  42 #define SUPERMICRO_NEW_BOARD    2
  43 /* Broken BIOS */
  44 #define BROKEN_BIOS             911
  45
  46 static int vendorsupport;
  47 module_param(vendorsupport, int, 0);
  48 MODULE_PARM_DESC(vendorsupport, "iTCO vendor specific support mode, default="
  49                         "0 (none), 1=SuperMicro Pent3, 2=SuperMicro Pent4+, "
  50                                                         "911=Broken SMI BIOS");
  51
  52 /*
  53  *      Vendor Specific Support
  54  */
  55
  56 /*
  57  *      Vendor Support: 1
  58  *      Board: Super Micro Computer Inc. 370SSE+-OEM1/P3TSSE
  59  *      iTCO chipset: ICH2
  60  *
  61  *      Code contributed by: R. Seretny <lkpatches@paypc.com>
  62  *      Documentation obtained by R. Seretny from SuperMicro Technical Support
  63  *
  64  *      To enable Watchdog function:
  65  *          BIOS setup -> Power -> TCO Logic SMI Enable -> Within5Minutes
  66  *          This setting enables SMI to clear the watchdog expired flag.
  67  *          If BIOS or CPU fail which may cause SMI hang, then system will
  68  *          reboot. When application starts to use watchdog function,
  69  *          application has to take over the control from SMI.
  70  *
  71  *          For P3TSSE, J36 jumper needs to be removed to enable the Watchdog
  72  *          function.
  73  *
  74  *          Note: The system will reboot when Expire Flag is set TWICE.
  75  *          So, if the watchdog timer is 20 seconds, then the maximum hang
  76  *          time is about 40 seconds, and the minimum hang time is about
  77  *          20.6 seconds.
  78  */
  79
  80 static void supermicro_old_pre_start(struct resource *smires)
  81 {
  82         unsigned long val32;
  83
  84         /* Bit 13: TCO_EN -> 0 = Disables TCO logic generating an SMI# */
  85         val32 = inl(smires->start);
  86         val32 &= 0xffffdfff;    /* Turn off SMI clearing watchdog */
  87         outl(val32, smires->start);     /* Needed to activate watchdog */
  88 }
  89
  90 static void supermicro_old_pre_stop(struct resource *smires)
  91 {
  92         unsigned long val32;
  93
  94         /* Bit 13: TCO_EN -> 1 = Enables the TCO logic to generate SMI# */
  95         val32 = inl(smires->start);
  96         val32 |= 0x00002000;    /* Turn on SMI clearing watchdog */
  97         outl(val32, smires->start);     /* Needed to deactivate watchdog */
  98 }
  99
 100 /*
 101  *      Vendor Support: 2
 102  *      Board: Super Micro Computer Inc. P4SBx, P4DPx
 103  *      iTCO chipset: ICH4
 104  *
 105  *      Code contributed by: R. Seretny <lkpatches@paypc.com>
 106  *      Documentation obtained by R. Seretny from SuperMicro Technical Support
 107  *
 108  *      To enable Watchdog function:
 109  *       1. BIOS
 110  *        For P4SBx:
 111  *        BIOS setup -> Advanced -> Integrated Peripherals -> Watch Dog Feature
 112  *        For P4DPx:
 113  *        BIOS setup -> Advanced -> I/O Device Configuration -> Watch Dog
 114  *       This setting enables or disables Watchdog function. When enabled, the
 115  *       default watchdog timer is set to be 5 minutes (about 4m35s). It is
 116  *       enough to load and run the OS. The application (service or driver) has
 117  *       to take over the control once OS is running up and before watchdog
 118  *       expires.
 119  *
 120  *       2. JUMPER
 121  *        For P4SBx: JP39
 122  *        For P4DPx: JP37
 123  *        This jumper is used for safety.  Closed is enabled. This jumper
 124  *        prevents user enables watchdog in BIOS by accident.
 125  *
 126  *       To enable Watch Dog function, both BIOS and JUMPER must be enabled.
 127  *
 128  *      The documentation lists motherboards P4SBx and P4DPx series as of
 129  *      20-March-2002. However, this code works flawlessly with much newer
 130  *      motherboards, such as my X6DHR-8G2 (SuperServer 6014H-82).
 131  *
 132  *      The original iTCO driver as written does not actually reset the
 133  *      watchdog timer on these machines, as a result they reboot after five
 134  *      minutes.
 135  *
 136  *      NOTE: You may leave the Watchdog function disabled in the SuperMicro
 137  *      BIOS to avoid a "boot-race"... This driver will enable watchdog
 138  *      functionality even if it's disabled in the BIOS once the /dev/watchdog
 139  *      file is opened.
 140  */
 141
 142 /* I/O Port's */
 143 #define SM_REGINDEX     0x2e    /* SuperMicro ICH4+ Register Index */
 144 #define SM_DATAIO       0x2f    /* SuperMicro ICH4+ Register Data I/O */
 145
 146 /* Control Register's */
 147 #define SM_CTLPAGESW    0x07    /* SuperMicro ICH4+ Control Page Switch */
 148 #define SM_CTLPAGE      0x08    /* SuperMicro ICH4+ Control Page Num */
 149
 150 #define SM_WATCHENABLE  0x30    /* Watchdog enable: Bit 0: 0=off, 1=on */
 151
 152 #define SM_WATCHPAGE    0x87    /* Watchdog unlock control page */
 153
 154 #define SM_ENDWATCH     0xAA    /* Watchdog lock control page */
 155
 156 #define SM_COUNTMODE    0xf5    /* Watchdog count mode select */
 157                                 /* (Bit 3: 0 = seconds, 1 = minutes */
 158
 159 #define SM_WATCHTIMER   0xf6    /* 8-bits, Watchdog timer counter (RW) */
 160
 161 #define SM_RESETCONTROL 0xf7    /* Watchdog reset control */
 162                                 /* Bit 6: timer is reset by kbd interrupt */
 163                                 /* Bit 7: timer is reset by mouse interrupt */
 164
 165 static void supermicro_new_unlock_watchdog(void)
 166 {
 167         /* Write 0x87 to port 0x2e twice */
 168         outb(SM_WATCHPAGE, SM_REGINDEX);
 169         outb(SM_WATCHPAGE, SM_REGINDEX);
 170         /* Switch to watchdog control page */
 171         outb(SM_CTLPAGESW, SM_REGINDEX);
 172         outb(SM_CTLPAGE, SM_DATAIO);
 173 }
 174
 175 static void supermicro_new_lock_watchdog(void)
 176 {
 177         outb(SM_ENDWATCH, SM_REGINDEX);
 178 }
 179
 180 static void supermicro_new_pre_start(unsigned int heartbeat)
 181 {
 182         unsigned int val;
 183
 184         supermicro_new_unlock_watchdog();
 185
 186         /* Watchdog timer setting needs to be in seconds*/
 187         outb(SM_COUNTMODE, SM_REGINDEX);
 188         val = inb(SM_DATAIO);
 189         val &= 0xF7;
 190         outb(val, SM_DATAIO);
 191
 192         /* Write heartbeat interval to WDOG */
 193         outb(SM_WATCHTIMER, SM_REGINDEX);
 194         outb((heartbeat & 255), SM_DATAIO);
 195
 196         /* Make sure keyboard/mouse interrupts don't interfere */
 197         outb(SM_RESETCONTROL, SM_REGINDEX);
 198         val = inb(SM_DATAIO);
 199         val &= 0x3f;
 200         outb(val, SM_DATAIO);
 201
 202         /* enable watchdog by setting bit 0 of Watchdog Enable to 1 */
 203         outb(SM_WATCHENABLE, SM_REGINDEX);
 204         val = inb(SM_DATAIO);
 205         val |= 0x01;
 206         outb(val, SM_DATAIO);
 207
 208         supermicro_new_lock_watchdog();
 209 }
 210
 211 static void supermicro_new_pre_stop(void)
 212 {
 213         unsigned int val;
 214
 215         supermicro_new_unlock_watchdog();
 216
 217         /* disable watchdog by setting bit 0 of Watchdog Enable to 0 */
 218         outb(SM_WATCHENABLE, SM_REGINDEX);
 219         val = inb(SM_DATAIO);
 220         val &= 0xFE;
 221         outb(val, SM_DATAIO);
 222
 223         supermicro_new_lock_watchdog();
 224 }
 225
 226 static void supermicro_new_pre_set_heartbeat(unsigned int heartbeat)
 227 {
 228         supermicro_new_unlock_watchdog();
 229
 230         /* reset watchdog timeout to heartveat value */
 231         outb(SM_WATCHTIMER, SM_REGINDEX);
 232         outb((heartbeat & 255), SM_DATAIO);
 233
 234         supermicro_new_lock_watchdog();
 235 }
 236
 237 /*
 238  *      Vendor Support: 911
 239  *      Board: Some Intel ICHx based motherboards
 240  *      iTCO chipset: ICH7+
 241  *
 242  *      Some Intel motherboards have a broken BIOS implementation: i.e.
 243  *      the SMI handler clear's the TIMEOUT bit in the TC01_STS register
 244  *      and does not reload the time. Thus the TCO watchdog does not reboot
 245  *      the system.
 246  *
 247  *      These are the conclusions of Andriy Gapon <avg@icyb.net.ua> after
 248  *      debugging: the SMI handler is quite simple - it tests value in
 249  *      TCO1_CNT against 0x800, i.e. checks TCO_TMR_HLT. If the bit is set
 250  *      the handler goes into an infinite loop, apparently to allow the
 251  *      second timeout and reboot. Otherwise it simply clears TIMEOUT bit
 252  *      in TCO1_STS and that's it.
 253  *      So the logic seems to be reversed, because it is hard to see how
 254  *      TIMEOUT can get set to 1 and SMI generated when TCO_TMR_HLT is set
 255  *      (other than a transitional effect).
 256  *
 257  *      The only fix found to get the motherboard(s) to reboot is to put
 258  *      the glb_smi_en bit to 0. This is a dirty hack that bypasses the
 259  *      broken code by disabling Global SMI.
 260  *
 261  *      WARNING: globally disabling SMI could possibly lead to dramatic
 262  *      problems, especially on laptops! I.e. various ACPI things where
 263  *      SMI is used for communication between OS and firmware.
 264  *
 265  *      Don't use this fix if you don't need to!!!
 266  */
 267
 268 static void broken_bios_start(struct resource *smires)
 269 {
 270         unsigned long val32;
 271
 272         val32 = inl(smires->start);
 273         /* Bit 13: TCO_EN     -> 0 = Disables TCO logic generating an SMI#
 274            Bit  0: GBL_SMI_EN -> 0 = No SMI# will be generated by ICH. */
 275         val32 &= 0xffffdffe;
 276         outl(val32, smires->start);
 277 }
 278
 279 static void broken_bios_stop(struct resource *smires)
 280 {
 281         unsigned long val32;
 282
 283         val32 = inl(smires->start);
 284         /* Bit 13: TCO_EN     -> 1 = Enables TCO logic generating an SMI#
 285            Bit  0: GBL_SMI_EN -> 1 = Turn global SMI on again. */
 286         val32 |= 0x00002001;
 287         outl(val32, smires->start);
 288 }
 289
 290 /*
 291  *      Generic Support Functions
 292  */
 293
 294 void iTCO_vendor_pre_start(struct resource *smires,
 295                            unsigned int heartbeat)
 296 {
 297         switch (vendorsupport) {
 298         case SUPERMICRO_OLD_BOARD:
 299                 supermicro_old_pre_start(smires);
 300                 break;
 301         case SUPERMICRO_NEW_BOARD:
 302                 supermicro_new_pre_start(heartbeat);
 303                 break;
 304         case BROKEN_BIOS:
 305                 broken_bios_start(smires);
 306                 break;
 307         }
 308 }
 309 EXPORT_SYMBOL(iTCO_vendor_pre_start);
 310
 311 void iTCO_vendor_pre_stop(struct resource *smires)
 312 {
 313         switch (vendorsupport) {
 314         case SUPERMICRO_OLD_BOARD:
 315                 supermicro_old_pre_stop(smires);
 316                 break;
 317         case SUPERMICRO_NEW_BOARD:
 318                 supermicro_new_pre_stop();
 319                 break;
 320         case BROKEN_BIOS:
 321                 broken_bios_stop(smires);
 322                 break;
 323         }
 324 }
 325 EXPORT_SYMBOL(iTCO_vendor_pre_stop);
 326
 327 void iTCO_vendor_pre_keepalive(struct resource *smires, unsigned int heartbeat)
 328 {
 329         if (vendorsupport == SUPERMICRO_NEW_BOARD)
 330                 supermicro_new_pre_set_heartbeat(heartbeat);
 331 }
 332 EXPORT_SYMBOL(iTCO_vendor_pre_keepalive);
 333
 334 void iTCO_vendor_pre_set_heartbeat(unsigned int heartbeat)
 335 {
 336         if (vendorsupport == SUPERMICRO_NEW_BOARD)
 337                 supermicro_new_pre_set_heartbeat(heartbeat);
 338 }
 339 EXPORT_SYMBOL(iTCO_vendor_pre_set_heartbeat);
 340
 341 int iTCO_vendor_check_noreboot_on(void)
 342 {
 343         switch (vendorsupport) {
 344         case SUPERMICRO_OLD_BOARD:
 345                 return 0;
 346         default:
 347                 return 1;
 348         }
 349 }
 350 EXPORT_SYMBOL(iTCO_vendor_check_noreboot_on);
 351
 352 static int __init iTCO_vendor_init_module(void)
 353 {
 354         pr_info("vendor-support=%d\n", vendorsupport);
 355         return 0;
 356 }
 357
 358 static void __exit iTCO_vendor_exit_module(void)
 359 {
 360         pr_info("Module Unloaded\n");
 361 }
 362
 363 module_init(iTCO_vendor_init_module);
 364 module_exit(iTCO_vendor_exit_module);
 365
 366 MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>, "
 367                 "R. Seretny <lkpatches@paypc.com>");
 368 MODULE_DESCRIPTION("Intel TCO Vendor Specific WatchDog Timer Driver Support");
 369 MODULE_VERSION(DRV_VERSION);
 370 MODULE_LICENSE("GPL");
 371