3 #endif /* CONFIG_KDB */
4 #include <linux/module.h>
5 #include <linux/init.h>
6 #include <linux/reboot.h>
7 #include <linux/init.h>
10 #include <acpi/reboot.h>
15 #include <asm/reboot_fixups.h>
16 #include <asm/reboot.h>
19 # include <linux/dmi.h>
20 # include <linux/ctype.h>
21 # include <linux/mc146818rtc.h>
22 # include <asm/pgtable.h>
24 # include <asm/iommu.h>
28 * Power off function, if any
30 void (*pm_power_off)(void);
31 EXPORT_SYMBOL(pm_power_off);
33 static long no_idt[3];
34 static int reboot_mode;
35 enum reboot_type reboot_type = BOOT_KBD;
38 #if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
39 static int reboot_cpu = -1;
42 /* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old]
43 warm Don't set the cold reboot flag
44 cold Set the cold reboot flag
45 bios Reboot by jumping through the BIOS (only for X86_32)
46 smp Reboot by executing reset on BSP or other CPU (only for X86_32)
47 triple Force a triple fault (init)
48 kbd Use the keyboard controller. cold reset (default)
49 acpi Use the RESET_REG in the FADT
50 efi Use efi reset_system runtime service
51 force Avoid anything that could hang.
53 static int __init reboot_setup(char *str)
68 if (isdigit(*(str+1))) {
69 reboot_cpu = (int) (*(str+1) - '0');
70 if (isdigit(*(str+2)))
71 reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
73 /* we will leave sorting out the final value
74 when we are ready to reboot, since we might not
75 have set up boot_cpu_id or smp_num_cpu */
77 #endif /* CONFIG_SMP */
93 str = strchr(str, ',');
102 __setup("reboot=", reboot_setup);
107 * Reboot options and system auto-detection code provided by
108 * Dell Inc. so their systems "just work". :-)
112 * Some machines require the "reboot=b" commandline option,
113 * this quirk makes that automatic.
115 static int __init set_bios_reboot(const struct dmi_system_id *d)
117 if (reboot_type != BOOT_BIOS) {
118 reboot_type = BOOT_BIOS;
119 printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
124 static struct dmi_system_id __initdata reboot_dmi_table[] = {
125 { /* Handle problems with rebooting on Dell E520's */
126 .callback = set_bios_reboot,
127 .ident = "Dell E520",
129 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
130 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
133 { /* Handle problems with rebooting on Dell 1300's */
134 .callback = set_bios_reboot,
135 .ident = "Dell PowerEdge 1300",
137 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
138 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
141 { /* Handle problems with rebooting on Dell 300's */
142 .callback = set_bios_reboot,
143 .ident = "Dell PowerEdge 300",
145 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
146 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
149 { /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
150 .callback = set_bios_reboot,
151 .ident = "Dell OptiPlex 745",
153 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
154 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
155 DMI_MATCH(DMI_BOARD_NAME, "0WF810"),
158 { /* Handle problems with rebooting on Dell 2400's */
159 .callback = set_bios_reboot,
160 .ident = "Dell PowerEdge 2400",
162 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
163 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
166 { /* Handle problems with rebooting on HP laptops */
167 .callback = set_bios_reboot,
168 .ident = "HP Compaq Laptop",
170 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
171 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
177 static int __init reboot_init(void)
179 dmi_check_system(reboot_dmi_table);
182 core_initcall(reboot_init);
184 /* The following code and data reboots the machine by switching to real
185 mode and jumping to the BIOS reset entry point, as if the CPU has
186 really been reset. The previous version asked the keyboard
187 controller to pulse the CPU reset line, which is more thorough, but
188 doesn't work with at least one type of 486 motherboard. It is easy
189 to stop this code working; hence the copious comments. */
190 static unsigned long long
191 real_mode_gdt_entries [3] =
193 0x0000000000000000ULL, /* Null descriptor */
194 0x00009a000000ffffULL, /* 16-bit real-mode 64k code at 0x00000000 */
195 0x000092000100ffffULL /* 16-bit real-mode 64k data at 0x00000100 */
198 static struct desc_ptr
199 real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries },
200 real_mode_idt = { 0x3ff, 0 };
202 /* This is 16-bit protected mode code to disable paging and the cache,
203 switch to real mode and jump to the BIOS reset code.
205 The instruction that switches to real mode by writing to CR0 must be
206 followed immediately by a far jump instruction, which set CS to a
207 valid value for real mode, and flushes the prefetch queue to avoid
208 running instructions that have already been decoded in protected
211 Clears all the flags except ET, especially PG (paging), PE
212 (protected-mode enable) and TS (task switch for coprocessor state
213 save). Flushes the TLB after paging has been disabled. Sets CD and
214 NW, to disable the cache on a 486, and invalidates the cache. This
215 is more like the state of a 486 after reset. I don't know if
216 something else should be done for other chips.
218 More could be done here to set up the registers as if a CPU reset had
219 occurred; hopefully real BIOSs don't assume much. */
220 static unsigned char real_mode_switch [] =
222 0x66, 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */
223 0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */
224 0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */
225 0x66, 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */
226 0x66, 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */
227 0x66, 0x0f, 0x20, 0xc3, /* movl %cr0,%ebx */
228 0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%ebx */
229 0x74, 0x02, /* jz f */
230 0x0f, 0x09, /* wbinvd */
231 0x24, 0x10, /* f: andb $0x10,al */
232 0x66, 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */
234 static unsigned char jump_to_bios [] =
236 0xea, 0x00, 0x00, 0xff, 0xff /* ljmp $0xffff,$0x0000 */
240 * Switch to real mode and then execute the code
241 * specified by the code and length parameters.
242 * We assume that length will aways be less that 100!
244 void machine_real_restart(unsigned char *code, int length)
248 /* Write zero to CMOS register number 0x0f, which the BIOS POST
249 routine will recognize as telling it to do a proper reboot. (Well
250 that's what this book in front of me says -- it may only apply to
251 the Phoenix BIOS though, it's not clear). At the same time,
252 disable NMIs by setting the top bit in the CMOS address register,
253 as we're about to do peculiar things to the CPU. I'm not sure if
254 `outb_p' is needed instead of just `outb'. Use it to be on the
255 safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
257 spin_lock(&rtc_lock);
258 CMOS_WRITE(0x00, 0x8f);
259 spin_unlock(&rtc_lock);
261 /* Remap the kernel at virtual address zero, as well as offset zero
262 from the kernel segment. This assumes the kernel segment starts at
263 virtual address PAGE_OFFSET. */
264 memcpy(swapper_pg_dir, swapper_pg_dir + USER_PGD_PTRS,
265 sizeof(swapper_pg_dir [0]) * KERNEL_PGD_PTRS);
268 * Use `swapper_pg_dir' as our page directory.
270 load_cr3(swapper_pg_dir);
272 /* Write 0x1234 to absolute memory location 0x472. The BIOS reads
273 this on booting to tell it to "Bypass memory test (also warm
274 boot)". This seems like a fairly standard thing that gets set by
275 REBOOT.COM programs, and the previous reset routine did this
277 *((unsigned short *)0x472) = reboot_mode;
279 /* For the switch to real mode, copy some code to low memory. It has
280 to be in the first 64k because it is running in 16-bit mode, and it
281 has to have the same physical and virtual address, because it turns
282 off paging. Copy it near the end of the first page, out of the way
283 of BIOS variables. */
284 memcpy((void *)(0x1000 - sizeof(real_mode_switch) - 100),
285 real_mode_switch, sizeof (real_mode_switch));
286 memcpy((void *)(0x1000 - 100), code, length);
288 /* Set up the IDT for real mode. */
289 load_idt(&real_mode_idt);
291 /* Set up a GDT from which we can load segment descriptors for real
292 mode. The GDT is not used in real mode; it is just needed here to
293 prepare the descriptors. */
294 load_gdt(&real_mode_gdt);
296 /* Load the data segment registers, and thus the descriptors ready for
297 real mode. The base address of each segment is 0x100, 16 times the
298 selector value being loaded here. This is so that the segment
299 registers don't have to be reloaded after switching to real mode:
300 the values are consistent for real mode operation already. */
301 __asm__ __volatile__ ("movl $0x0010,%%eax\n"
302 "\tmovl %%eax,%%ds\n"
303 "\tmovl %%eax,%%es\n"
304 "\tmovl %%eax,%%fs\n"
305 "\tmovl %%eax,%%gs\n"
306 "\tmovl %%eax,%%ss" : : : "eax");
308 /* Jump to the 16-bit code that we copied earlier. It disables paging
309 and the cache, switches to real mode, and jumps to the BIOS reset
311 __asm__ __volatile__ ("ljmp $0x0008,%0"
313 : "i" ((void *)(0x1000 - sizeof (real_mode_switch) - 100)));
315 #ifdef CONFIG_APM_MODULE
316 EXPORT_SYMBOL(machine_real_restart);
319 #endif /* CONFIG_X86_32 */
321 static inline void kb_wait(void)
325 for (i = 0; i < 0x10000; i++) {
326 if ((inb(0x64) & 0x02) == 0)
332 static void native_machine_emergency_restart(void)
336 /* Tell the BIOS if we want cold or warm reboot */
337 *((unsigned short *)__va(0x472)) = reboot_mode;
340 /* Could also try the reset bit in the Hammer NB */
341 switch (reboot_type) {
343 for (i = 0; i < 10; i++) {
346 outb(0xfe, 0x64); /* pulse reset low */
351 load_idt((const struct desc_ptr *)&no_idt);
352 __asm__ __volatile__("int3");
354 reboot_type = BOOT_KBD;
359 machine_real_restart(jump_to_bios, sizeof(jump_to_bios));
361 reboot_type = BOOT_KBD;
367 reboot_type = BOOT_KBD;
373 efi.reset_system(reboot_mode ? EFI_RESET_WARM : EFI_RESET_COLD,
374 EFI_SUCCESS, 0, NULL);
376 reboot_type = BOOT_KBD;
382 static void native_machine_shutdown(void)
384 /* Stop the cpus and apics */
388 /* The boot cpu is always logical cpu 0 */
392 /* See if there has been given a command line override */
393 if ((reboot_cpu != -1) && (reboot_cpu < NR_CPUS) &&
394 cpu_isset(reboot_cpu, cpu_online_map))
395 reboot_cpu_id = reboot_cpu;
398 /* Make certain the cpu I'm about to reboot on is online */
399 if (!cpu_isset(reboot_cpu_id, cpu_online_map))
400 reboot_cpu_id = smp_processor_id();
402 /* Make certain I only run on the appropriate processor */
403 set_cpus_allowed(current, cpumask_of_cpu(reboot_cpu_id));
405 /* O.K Now that I'm on the appropriate processor,
406 * stop all of the others.
410 * If this restart is occuring while kdb is running (e.g. reboot
411 * command), the other CPU's are already stopped. Don't try to
412 * stop them yet again.
414 if (!KDB_IS_RUNNING())
415 #endif /* CONFIG_KDB */
421 #ifdef CONFIG_X86_IO_APIC
425 #ifdef CONFIG_HPET_TIMER
430 pci_iommu_shutdown();
434 static void native_machine_restart(char *__unused)
436 printk("machine restart\n");
440 machine_emergency_restart();
443 static void native_machine_halt(void)
447 static void native_machine_power_off(void)
456 struct machine_ops machine_ops = {
457 .power_off = native_machine_power_off,
458 .shutdown = native_machine_shutdown,
459 .emergency_restart = native_machine_emergency_restart,
460 .restart = native_machine_restart,
461 .halt = native_machine_halt
464 void machine_power_off(void)
466 machine_ops.power_off();
469 void machine_shutdown(void)
471 machine_ops.shutdown();
474 void machine_emergency_restart(void)
476 machine_ops.emergency_restart();
479 void machine_restart(char *cmd)
481 machine_ops.restart(cmd);
484 void machine_halt(void)