1 #include <linux/module.h> 2 #include <linux/reboot.h> 3 #include <linux/init.h> 4 #include <linux/pm.h> 5 #include <linux/efi.h> 6 #include <acpi/reboot.h> 7 #include <asm/io.h> 8 #include <asm/apic.h> 9 #include <asm/desc.h> 10 #include <asm/hpet.h> 11 #include <asm/reboot_fixups.h> 12 #include <asm/reboot.h> 13 14 #ifdef CONFIG_X86_32 15 # include <linux/dmi.h> 16 # include <linux/ctype.h> 17 # include <linux/mc146818rtc.h> 18 # include <asm/pgtable.h> 19 #else 20 # include <asm/iommu.h> 21 #endif 22 23 /* 24 * Power off function, if any 25 */ 26 void (*pm_power_off)(void); 27 EXPORT_SYMBOL(pm_power_off); 28 29 static long no_idt[3]; 30 static int reboot_mode; 31 enum reboot_type reboot_type = BOOT_KBD; 32 int reboot_force; 33 34 #if defined(CONFIG_X86_32) && defined(CONFIG_SMP) 35 static int reboot_cpu = -1; 36 #endif 37 38 /* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] 39 warm Don't set the cold reboot flag 40 cold Set the cold reboot flag 41 bios Reboot by jumping through the BIOS (only for X86_32) 42 smp Reboot by executing reset on BSP or other CPU (only for X86_32) 43 triple Force a triple fault (init) 44 kbd Use the keyboard controller. cold reset (default) 45 acpi Use the RESET_REG in the FADT 46 efi Use efi reset_system runtime service 47 force Avoid anything that could hang. 48 */ 49 static int __init reboot_setup(char *str) 50 { 51 for (;;) { 52 switch (*str) { 53 case 'w': 54 reboot_mode = 0x1234; 55 break; 56 57 case 'c': 58 reboot_mode = 0; 59 break; 60 61 #ifdef CONFIG_X86_32 62 #ifdef CONFIG_SMP 63 case 's': 64 if (isdigit(*(str+1))) { 65 reboot_cpu = (int) (*(str+1) - '0'); 66 if (isdigit(*(str+2))) 67 reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0'); 68 } 69 /* we will leave sorting out the final value 70 when we are ready to reboot, since we might not 71 have set up boot_cpu_id or smp_num_cpu */ 72 break; 73 #endif /* CONFIG_SMP */ 74 75 case 'b': 76 #endif 77 case 'a': 78 case 'k': 79 case 't': 80 case 'e': 81 reboot_type = *str; 82 break; 83 84 case 'f': 85 reboot_force = 1; 86 break; 87 } 88 89 str = strchr(str, ','); 90 if (str) 91 str++; 92 else 93 break; 94 } 95 return 1; 96 } 97 98 __setup("reboot=", reboot_setup); 99 100 101 #ifdef CONFIG_X86_32 102 /* 103 * Reboot options and system auto-detection code provided by 104 * Dell Inc. so their systems "just work". :-) 105 */ 106 107 /* 108 * Some machines require the "reboot=b" commandline option, 109 * this quirk makes that automatic. 110 */ 111 static int __init set_bios_reboot(const struct dmi_system_id *d) 112 { 113 if (reboot_type != BOOT_BIOS) { 114 reboot_type = BOOT_BIOS; 115 printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident); 116 } 117 return 0; 118 } 119 120 static struct dmi_system_id __initdata reboot_dmi_table[] = { 121 { /* Handle problems with rebooting on Dell E520's */ 122 .callback = set_bios_reboot, 123 .ident = "Dell E520", 124 .matches = { 125 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 126 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"), 127 }, 128 }, 129 { /* Handle problems with rebooting on Dell 1300's */ 130 .callback = set_bios_reboot, 131 .ident = "Dell PowerEdge 1300", 132 .matches = { 133 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 134 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"), 135 }, 136 }, 137 { /* Handle problems with rebooting on Dell 300's */ 138 .callback = set_bios_reboot, 139 .ident = "Dell PowerEdge 300", 140 .matches = { 141 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 142 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"), 143 }, 144 }, 145 { /* Handle problems with rebooting on Dell Optiplex 745's SFF*/ 146 .callback = set_bios_reboot, 147 .ident = "Dell OptiPlex 745", 148 .matches = { 149 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 150 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), 151 DMI_MATCH(DMI_BOARD_NAME, "0WF810"), 152 }, 153 }, 154 { /* Handle problems with rebooting on Dell Optiplex 745's DFF*/ 155 .callback = set_bios_reboot, 156 .ident = "Dell OptiPlex 745", 157 .matches = { 158 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 159 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), 160 DMI_MATCH(DMI_BOARD_NAME, "0MM599"), 161 }, 162 }, 163 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */ 164 .callback = set_bios_reboot, 165 .ident = "Dell OptiPlex 745", 166 .matches = { 167 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 168 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), 169 DMI_MATCH(DMI_BOARD_NAME, "0KW626"), 170 }, 171 }, 172 { /* Handle problems with rebooting on Dell 2400's */ 173 .callback = set_bios_reboot, 174 .ident = "Dell PowerEdge 2400", 175 .matches = { 176 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 177 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"), 178 }, 179 }, 180 { /* Handle problems with rebooting on HP laptops */ 181 .callback = set_bios_reboot, 182 .ident = "HP Compaq Laptop", 183 .matches = { 184 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), 185 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"), 186 }, 187 }, 188 { } 189 }; 190 191 static int __init reboot_init(void) 192 { 193 dmi_check_system(reboot_dmi_table); 194 return 0; 195 } 196 core_initcall(reboot_init); 197 198 /* The following code and data reboots the machine by switching to real 199 mode and jumping to the BIOS reset entry point, as if the CPU has 200 really been reset. The previous version asked the keyboard 201 controller to pulse the CPU reset line, which is more thorough, but 202 doesn't work with at least one type of 486 motherboard. It is easy 203 to stop this code working; hence the copious comments. */ 204 static unsigned long long 205 real_mode_gdt_entries [3] = 206 { 207 0x0000000000000000ULL, /* Null descriptor */ 208 0x00009a000000ffffULL, /* 16-bit real-mode 64k code at 0x00000000 */ 209 0x000092000100ffffULL /* 16-bit real-mode 64k data at 0x00000100 */ 210 }; 211 212 static struct desc_ptr 213 real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries }, 214 real_mode_idt = { 0x3ff, 0 }; 215 216 /* This is 16-bit protected mode code to disable paging and the cache, 217 switch to real mode and jump to the BIOS reset code. 218 219 The instruction that switches to real mode by writing to CR0 must be 220 followed immediately by a far jump instruction, which set CS to a 221 valid value for real mode, and flushes the prefetch queue to avoid 222 running instructions that have already been decoded in protected 223 mode. 224 225 Clears all the flags except ET, especially PG (paging), PE 226 (protected-mode enable) and TS (task switch for coprocessor state 227 save). Flushes the TLB after paging has been disabled. Sets CD and 228 NW, to disable the cache on a 486, and invalidates the cache. This 229 is more like the state of a 486 after reset. I don't know if 230 something else should be done for other chips. 231 232 More could be done here to set up the registers as if a CPU reset had 233 occurred; hopefully real BIOSs don't assume much. */ 234 static unsigned char real_mode_switch [] = 235 { 236 0x66, 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */ 237 0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */ 238 0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */ 239 0x66, 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */ 240 0x66, 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */ 241 0x66, 0x0f, 0x20, 0xc3, /* movl %cr0,%ebx */ 242 0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%ebx */ 243 0x74, 0x02, /* jz f */ 244 0x0f, 0x09, /* wbinvd */ 245 0x24, 0x10, /* f: andb $0x10,al */ 246 0x66, 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */ 247 }; 248 static unsigned char jump_to_bios [] = 249 { 250 0xea, 0x00, 0x00, 0xff, 0xff /* ljmp $0xffff,$0x0000 */ 251 }; 252 253 /* 254 * Switch to real mode and then execute the code 255 * specified by the code and length parameters. 256 * We assume that length will aways be less that 100! 257 */ 258 void machine_real_restart(unsigned char *code, int length) 259 { 260 local_irq_disable(); 261 262 /* Write zero to CMOS register number 0x0f, which the BIOS POST 263 routine will recognize as telling it to do a proper reboot. (Well 264 that's what this book in front of me says -- it may only apply to 265 the Phoenix BIOS though, it's not clear). At the same time, 266 disable NMIs by setting the top bit in the CMOS address register, 267 as we're about to do peculiar things to the CPU. I'm not sure if 268 `outb_p' is needed instead of just `outb'. Use it to be on the 269 safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.) 270 */ 271 spin_lock(&rtc_lock); 272 CMOS_WRITE(0x00, 0x8f); 273 spin_unlock(&rtc_lock); 274 275 /* Remap the kernel at virtual address zero, as well as offset zero 276 from the kernel segment. This assumes the kernel segment starts at 277 virtual address PAGE_OFFSET. */ 278 memcpy(swapper_pg_dir, swapper_pg_dir + USER_PGD_PTRS, 279 sizeof(swapper_pg_dir [0]) * KERNEL_PGD_PTRS); 280 281 /* 282 * Use `swapper_pg_dir' as our page directory. 283 */ 284 load_cr3(swapper_pg_dir); 285 286 /* Write 0x1234 to absolute memory location 0x472. The BIOS reads 287 this on booting to tell it to "Bypass memory test (also warm 288 boot)". This seems like a fairly standard thing that gets set by 289 REBOOT.COM programs, and the previous reset routine did this 290 too. */ 291 *((unsigned short *)0x472) = reboot_mode; 292 293 /* For the switch to real mode, copy some code to low memory. It has 294 to be in the first 64k because it is running in 16-bit mode, and it 295 has to have the same physical and virtual address, because it turns 296 off paging. Copy it near the end of the first page, out of the way 297 of BIOS variables. */ 298 memcpy((void *)(0x1000 - sizeof(real_mode_switch) - 100), 299 real_mode_switch, sizeof (real_mode_switch)); 300 memcpy((void *)(0x1000 - 100), code, length); 301 302 /* Set up the IDT for real mode. */ 303 load_idt(&real_mode_idt); 304 305 /* Set up a GDT from which we can load segment descriptors for real 306 mode. The GDT is not used in real mode; it is just needed here to 307 prepare the descriptors. */ 308 load_gdt(&real_mode_gdt); 309 310 /* Load the data segment registers, and thus the descriptors ready for 311 real mode. The base address of each segment is 0x100, 16 times the 312 selector value being loaded here. This is so that the segment 313 registers don't have to be reloaded after switching to real mode: 314 the values are consistent for real mode operation already. */ 315 __asm__ __volatile__ ("movl $0x0010,%%eax\n" 316 "\tmovl %%eax,%%ds\n" 317 "\tmovl %%eax,%%es\n" 318 "\tmovl %%eax,%%fs\n" 319 "\tmovl %%eax,%%gs\n" 320 "\tmovl %%eax,%%ss" : : : "eax"); 321 322 /* Jump to the 16-bit code that we copied earlier. It disables paging 323 and the cache, switches to real mode, and jumps to the BIOS reset 324 entry point. */ 325 __asm__ __volatile__ ("ljmp $0x0008,%0" 326 : 327 : "i" ((void *)(0x1000 - sizeof (real_mode_switch) - 100))); 328 } 329 #ifdef CONFIG_APM_MODULE 330 EXPORT_SYMBOL(machine_real_restart); 331 #endif 332 333 #endif /* CONFIG_X86_32 */ 334 335 static inline void kb_wait(void) 336 { 337 int i; 338 339 for (i = 0; i < 0x10000; i++) { 340 if ((inb(0x64) & 0x02) == 0) 341 break; 342 udelay(2); 343 } 344 } 345 346 void __attribute__((weak)) mach_reboot_fixups(void) 347 { 348 } 349 350 static void native_machine_emergency_restart(void) 351 { 352 int i; 353 354 /* Tell the BIOS if we want cold or warm reboot */ 355 *((unsigned short *)__va(0x472)) = reboot_mode; 356 357 for (;;) { 358 /* Could also try the reset bit in the Hammer NB */ 359 switch (reboot_type) { 360 case BOOT_KBD: 361 mach_reboot_fixups(); /* for board specific fixups */ 362 363 for (i = 0; i < 10; i++) { 364 kb_wait(); 365 udelay(50); 366 outb(0xfe, 0x64); /* pulse reset low */ 367 udelay(50); 368 } 369 370 case BOOT_TRIPLE: 371 load_idt((const struct desc_ptr *)&no_idt); 372 __asm__ __volatile__("int3"); 373 374 reboot_type = BOOT_KBD; 375 break; 376 377 #ifdef CONFIG_X86_32 378 case BOOT_BIOS: 379 machine_real_restart(jump_to_bios, sizeof(jump_to_bios)); 380 381 reboot_type = BOOT_KBD; 382 break; 383 #endif 384 385 case BOOT_ACPI: 386 acpi_reboot(); 387 reboot_type = BOOT_KBD; 388 break; 389 390 391 case BOOT_EFI: 392 if (efi_enabled) 393 efi.reset_system(reboot_mode ? EFI_RESET_WARM : EFI_RESET_COLD, 394 EFI_SUCCESS, 0, NULL); 395 396 reboot_type = BOOT_KBD; 397 break; 398 } 399 } 400 } 401 402 static void native_machine_shutdown(void) 403 { 404 /* Stop the cpus and apics */ 405 #ifdef CONFIG_SMP 406 int reboot_cpu_id; 407 408 /* The boot cpu is always logical cpu 0 */ 409 reboot_cpu_id = 0; 410 411 #ifdef CONFIG_X86_32 412 /* See if there has been given a command line override */ 413 if ((reboot_cpu != -1) && (reboot_cpu < NR_CPUS) && 414 cpu_online(reboot_cpu)) 415 reboot_cpu_id = reboot_cpu; 416 #endif 417 418 /* Make certain the cpu I'm about to reboot on is online */ 419 if (!cpu_online(reboot_cpu_id)) 420 reboot_cpu_id = smp_processor_id(); 421 422 /* Make certain I only run on the appropriate processor */ 423 set_cpus_allowed(current, cpumask_of_cpu(reboot_cpu_id)); 424 425 /* O.K Now that I'm on the appropriate processor, 426 * stop all of the others. 427 */ 428 smp_send_stop(); 429 #endif 430 431 lapic_shutdown(); 432 433 #ifdef CONFIG_X86_IO_APIC 434 disable_IO_APIC(); 435 #endif 436 437 #ifdef CONFIG_HPET_TIMER 438 hpet_disable(); 439 #endif 440 441 #ifdef CONFIG_X86_64 442 pci_iommu_shutdown(); 443 #endif 444 } 445 446 static void native_machine_restart(char *__unused) 447 { 448 printk("machine restart\n"); 449 450 if (!reboot_force) 451 machine_shutdown(); 452 machine_emergency_restart(); 453 } 454 455 static void native_machine_halt(void) 456 { 457 } 458 459 static void native_machine_power_off(void) 460 { 461 if (pm_power_off) { 462 if (!reboot_force) 463 machine_shutdown(); 464 pm_power_off(); 465 } 466 } 467 468 struct machine_ops machine_ops = { 469 .power_off = native_machine_power_off, 470 .shutdown = native_machine_shutdown, 471 .emergency_restart = native_machine_emergency_restart, 472 .restart = native_machine_restart, 473 .halt = native_machine_halt 474 }; 475 476 void machine_power_off(void) 477 { 478 machine_ops.power_off(); 479 } 480 481 void machine_shutdown(void) 482 { 483 machine_ops.shutdown(); 484 } 485 486 void machine_emergency_restart(void) 487 { 488 machine_ops.emergency_restart(); 489 } 490 491 void machine_restart(char *cmd) 492 { 493 machine_ops.restart(cmd); 494 } 495 496 void machine_halt(void) 497 { 498 machine_ops.halt(); 499 } 500 501