diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/i386/kernel/reboot.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/i386/kernel/reboot.c')
-rw-r--r-- | arch/i386/kernel/reboot.c | 382 |
1 files changed, 382 insertions, 0 deletions
diff --git a/arch/i386/kernel/reboot.c b/arch/i386/kernel/reboot.c new file mode 100644 index 000000000000..3d7e994563df --- /dev/null +++ b/arch/i386/kernel/reboot.c | |||
@@ -0,0 +1,382 @@ | |||
1 | /* | ||
2 | * linux/arch/i386/kernel/reboot.c | ||
3 | */ | ||
4 | |||
5 | #include <linux/mm.h> | ||
6 | #include <linux/module.h> | ||
7 | #include <linux/delay.h> | ||
8 | #include <linux/init.h> | ||
9 | #include <linux/interrupt.h> | ||
10 | #include <linux/mc146818rtc.h> | ||
11 | #include <linux/efi.h> | ||
12 | #include <linux/dmi.h> | ||
13 | #include <asm/uaccess.h> | ||
14 | #include <asm/apic.h> | ||
15 | #include "mach_reboot.h" | ||
16 | |||
17 | /* | ||
18 | * Power off function, if any | ||
19 | */ | ||
20 | void (*pm_power_off)(void); | ||
21 | |||
22 | static int reboot_mode; | ||
23 | static int reboot_thru_bios; | ||
24 | |||
25 | #ifdef CONFIG_SMP | ||
26 | int reboot_smp = 0; | ||
27 | static int reboot_cpu = -1; | ||
28 | /* shamelessly grabbed from lib/vsprintf.c for readability */ | ||
29 | #define is_digit(c) ((c) >= '0' && (c) <= '9') | ||
30 | #endif | ||
31 | static int __init reboot_setup(char *str) | ||
32 | { | ||
33 | while(1) { | ||
34 | switch (*str) { | ||
35 | case 'w': /* "warm" reboot (no memory testing etc) */ | ||
36 | reboot_mode = 0x1234; | ||
37 | break; | ||
38 | case 'c': /* "cold" reboot (with memory testing etc) */ | ||
39 | reboot_mode = 0x0; | ||
40 | break; | ||
41 | case 'b': /* "bios" reboot by jumping through the BIOS */ | ||
42 | reboot_thru_bios = 1; | ||
43 | break; | ||
44 | case 'h': /* "hard" reboot by toggling RESET and/or crashing the CPU */ | ||
45 | reboot_thru_bios = 0; | ||
46 | break; | ||
47 | #ifdef CONFIG_SMP | ||
48 | case 's': /* "smp" reboot by executing reset on BSP or other CPU*/ | ||
49 | reboot_smp = 1; | ||
50 | if (is_digit(*(str+1))) { | ||
51 | reboot_cpu = (int) (*(str+1) - '0'); | ||
52 | if (is_digit(*(str+2))) | ||
53 | reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0'); | ||
54 | } | ||
55 | /* we will leave sorting out the final value | ||
56 | when we are ready to reboot, since we might not | ||
57 | have set up boot_cpu_id or smp_num_cpu */ | ||
58 | break; | ||
59 | #endif | ||
60 | } | ||
61 | if((str = strchr(str,',')) != NULL) | ||
62 | str++; | ||
63 | else | ||
64 | break; | ||
65 | } | ||
66 | return 1; | ||
67 | } | ||
68 | |||
69 | __setup("reboot=", reboot_setup); | ||
70 | |||
71 | /* | ||
72 | * Reboot options and system auto-detection code provided by | ||
73 | * Dell Inc. so their systems "just work". :-) | ||
74 | */ | ||
75 | |||
76 | /* | ||
77 | * Some machines require the "reboot=b" commandline option, this quirk makes that automatic. | ||
78 | */ | ||
79 | static int __init set_bios_reboot(struct dmi_system_id *d) | ||
80 | { | ||
81 | if (!reboot_thru_bios) { | ||
82 | reboot_thru_bios = 1; | ||
83 | printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident); | ||
84 | } | ||
85 | return 0; | ||
86 | } | ||
87 | |||
88 | /* | ||
89 | * Some machines require the "reboot=s" commandline option, this quirk makes that automatic. | ||
90 | */ | ||
91 | static int __init set_smp_reboot(struct dmi_system_id *d) | ||
92 | { | ||
93 | #ifdef CONFIG_SMP | ||
94 | if (!reboot_smp) { | ||
95 | reboot_smp = 1; | ||
96 | printk(KERN_INFO "%s series board detected. Selecting SMP-method for reboots.\n", d->ident); | ||
97 | } | ||
98 | #endif | ||
99 | return 0; | ||
100 | } | ||
101 | |||
102 | /* | ||
103 | * Some machines require the "reboot=b,s" commandline option, this quirk makes that automatic. | ||
104 | */ | ||
105 | static int __init set_smp_bios_reboot(struct dmi_system_id *d) | ||
106 | { | ||
107 | set_smp_reboot(d); | ||
108 | set_bios_reboot(d); | ||
109 | return 0; | ||
110 | } | ||
111 | |||
112 | static struct dmi_system_id __initdata reboot_dmi_table[] = { | ||
113 | { /* Handle problems with rebooting on Dell 1300's */ | ||
114 | .callback = set_smp_bios_reboot, | ||
115 | .ident = "Dell PowerEdge 1300", | ||
116 | .matches = { | ||
117 | DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), | ||
118 | DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"), | ||
119 | }, | ||
120 | }, | ||
121 | { /* Handle problems with rebooting on Dell 300's */ | ||
122 | .callback = set_bios_reboot, | ||
123 | .ident = "Dell PowerEdge 300", | ||
124 | .matches = { | ||
125 | DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), | ||
126 | DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"), | ||
127 | }, | ||
128 | }, | ||
129 | { /* Handle problems with rebooting on Dell 2400's */ | ||
130 | .callback = set_bios_reboot, | ||
131 | .ident = "Dell PowerEdge 2400", | ||
132 | .matches = { | ||
133 | DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), | ||
134 | DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"), | ||
135 | }, | ||
136 | }, | ||
137 | { } | ||
138 | }; | ||
139 | |||
140 | static int __init reboot_init(void) | ||
141 | { | ||
142 | dmi_check_system(reboot_dmi_table); | ||
143 | return 0; | ||
144 | } | ||
145 | |||
146 | core_initcall(reboot_init); | ||
147 | |||
148 | /* The following code and data reboots the machine by switching to real | ||
149 | mode and jumping to the BIOS reset entry point, as if the CPU has | ||
150 | really been reset. The previous version asked the keyboard | ||
151 | controller to pulse the CPU reset line, which is more thorough, but | ||
152 | doesn't work with at least one type of 486 motherboard. It is easy | ||
153 | to stop this code working; hence the copious comments. */ | ||
154 | |||
155 | static unsigned long long | ||
156 | real_mode_gdt_entries [3] = | ||
157 | { | ||
158 | 0x0000000000000000ULL, /* Null descriptor */ | ||
159 | 0x00009a000000ffffULL, /* 16-bit real-mode 64k code at 0x00000000 */ | ||
160 | 0x000092000100ffffULL /* 16-bit real-mode 64k data at 0x00000100 */ | ||
161 | }; | ||
162 | |||
163 | static struct | ||
164 | { | ||
165 | unsigned short size __attribute__ ((packed)); | ||
166 | unsigned long long * base __attribute__ ((packed)); | ||
167 | } | ||
168 | real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, real_mode_gdt_entries }, | ||
169 | real_mode_idt = { 0x3ff, NULL }, | ||
170 | no_idt = { 0, NULL }; | ||
171 | |||
172 | |||
173 | /* This is 16-bit protected mode code to disable paging and the cache, | ||
174 | switch to real mode and jump to the BIOS reset code. | ||
175 | |||
176 | The instruction that switches to real mode by writing to CR0 must be | ||
177 | followed immediately by a far jump instruction, which set CS to a | ||
178 | valid value for real mode, and flushes the prefetch queue to avoid | ||
179 | running instructions that have already been decoded in protected | ||
180 | mode. | ||
181 | |||
182 | Clears all the flags except ET, especially PG (paging), PE | ||
183 | (protected-mode enable) and TS (task switch for coprocessor state | ||
184 | save). Flushes the TLB after paging has been disabled. Sets CD and | ||
185 | NW, to disable the cache on a 486, and invalidates the cache. This | ||
186 | is more like the state of a 486 after reset. I don't know if | ||
187 | something else should be done for other chips. | ||
188 | |||
189 | More could be done here to set up the registers as if a CPU reset had | ||
190 | occurred; hopefully real BIOSs don't assume much. */ | ||
191 | |||
192 | static unsigned char real_mode_switch [] = | ||
193 | { | ||
194 | 0x66, 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */ | ||
195 | 0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */ | ||
196 | 0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */ | ||
197 | 0x66, 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */ | ||
198 | 0x66, 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */ | ||
199 | 0x66, 0x0f, 0x20, 0xc3, /* movl %cr0,%ebx */ | ||
200 | 0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%ebx */ | ||
201 | 0x74, 0x02, /* jz f */ | ||
202 | 0x0f, 0x09, /* wbinvd */ | ||
203 | 0x24, 0x10, /* f: andb $0x10,al */ | ||
204 | 0x66, 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */ | ||
205 | }; | ||
206 | static unsigned char jump_to_bios [] = | ||
207 | { | ||
208 | 0xea, 0x00, 0x00, 0xff, 0xff /* ljmp $0xffff,$0x0000 */ | ||
209 | }; | ||
210 | |||
211 | /* | ||
212 | * Switch to real mode and then execute the code | ||
213 | * specified by the code and length parameters. | ||
214 | * We assume that length will aways be less that 100! | ||
215 | */ | ||
216 | void machine_real_restart(unsigned char *code, int length) | ||
217 | { | ||
218 | unsigned long flags; | ||
219 | |||
220 | local_irq_disable(); | ||
221 | |||
222 | /* Write zero to CMOS register number 0x0f, which the BIOS POST | ||
223 | routine will recognize as telling it to do a proper reboot. (Well | ||
224 | that's what this book in front of me says -- it may only apply to | ||
225 | the Phoenix BIOS though, it's not clear). At the same time, | ||
226 | disable NMIs by setting the top bit in the CMOS address register, | ||
227 | as we're about to do peculiar things to the CPU. I'm not sure if | ||
228 | `outb_p' is needed instead of just `outb'. Use it to be on the | ||
229 | safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.) | ||
230 | */ | ||
231 | |||
232 | spin_lock_irqsave(&rtc_lock, flags); | ||
233 | CMOS_WRITE(0x00, 0x8f); | ||
234 | spin_unlock_irqrestore(&rtc_lock, flags); | ||
235 | |||
236 | /* Remap the kernel at virtual address zero, as well as offset zero | ||
237 | from the kernel segment. This assumes the kernel segment starts at | ||
238 | virtual address PAGE_OFFSET. */ | ||
239 | |||
240 | memcpy (swapper_pg_dir, swapper_pg_dir + USER_PGD_PTRS, | ||
241 | sizeof (swapper_pg_dir [0]) * KERNEL_PGD_PTRS); | ||
242 | |||
243 | /* | ||
244 | * Use `swapper_pg_dir' as our page directory. | ||
245 | */ | ||
246 | load_cr3(swapper_pg_dir); | ||
247 | |||
248 | /* Write 0x1234 to absolute memory location 0x472. The BIOS reads | ||
249 | this on booting to tell it to "Bypass memory test (also warm | ||
250 | boot)". This seems like a fairly standard thing that gets set by | ||
251 | REBOOT.COM programs, and the previous reset routine did this | ||
252 | too. */ | ||
253 | |||
254 | *((unsigned short *)0x472) = reboot_mode; | ||
255 | |||
256 | /* For the switch to real mode, copy some code to low memory. It has | ||
257 | to be in the first 64k because it is running in 16-bit mode, and it | ||
258 | has to have the same physical and virtual address, because it turns | ||
259 | off paging. Copy it near the end of the first page, out of the way | ||
260 | of BIOS variables. */ | ||
261 | |||
262 | memcpy ((void *) (0x1000 - sizeof (real_mode_switch) - 100), | ||
263 | real_mode_switch, sizeof (real_mode_switch)); | ||
264 | memcpy ((void *) (0x1000 - 100), code, length); | ||
265 | |||
266 | /* Set up the IDT for real mode. */ | ||
267 | |||
268 | __asm__ __volatile__ ("lidt %0" : : "m" (real_mode_idt)); | ||
269 | |||
270 | /* Set up a GDT from which we can load segment descriptors for real | ||
271 | mode. The GDT is not used in real mode; it is just needed here to | ||
272 | prepare the descriptors. */ | ||
273 | |||
274 | __asm__ __volatile__ ("lgdt %0" : : "m" (real_mode_gdt)); | ||
275 | |||
276 | /* Load the data segment registers, and thus the descriptors ready for | ||
277 | real mode. The base address of each segment is 0x100, 16 times the | ||
278 | selector value being loaded here. This is so that the segment | ||
279 | registers don't have to be reloaded after switching to real mode: | ||
280 | the values are consistent for real mode operation already. */ | ||
281 | |||
282 | __asm__ __volatile__ ("movl $0x0010,%%eax\n" | ||
283 | "\tmovl %%eax,%%ds\n" | ||
284 | "\tmovl %%eax,%%es\n" | ||
285 | "\tmovl %%eax,%%fs\n" | ||
286 | "\tmovl %%eax,%%gs\n" | ||
287 | "\tmovl %%eax,%%ss" : : : "eax"); | ||
288 | |||
289 | /* Jump to the 16-bit code that we copied earlier. It disables paging | ||
290 | and the cache, switches to real mode, and jumps to the BIOS reset | ||
291 | entry point. */ | ||
292 | |||
293 | __asm__ __volatile__ ("ljmp $0x0008,%0" | ||
294 | : | ||
295 | : "i" ((void *) (0x1000 - sizeof (real_mode_switch) - 100))); | ||
296 | } | ||
297 | |||
298 | void machine_restart(char * __unused) | ||
299 | { | ||
300 | #ifdef CONFIG_SMP | ||
301 | int cpuid; | ||
302 | |||
303 | cpuid = GET_APIC_ID(apic_read(APIC_ID)); | ||
304 | |||
305 | if (reboot_smp) { | ||
306 | |||
307 | /* check to see if reboot_cpu is valid | ||
308 | if its not, default to the BSP */ | ||
309 | if ((reboot_cpu == -1) || | ||
310 | (reboot_cpu > (NR_CPUS -1)) || | ||
311 | !physid_isset(cpuid, phys_cpu_present_map)) | ||
312 | reboot_cpu = boot_cpu_physical_apicid; | ||
313 | |||
314 | reboot_smp = 0; /* use this as a flag to only go through this once*/ | ||
315 | /* re-run this function on the other CPUs | ||
316 | it will fall though this section since we have | ||
317 | cleared reboot_smp, and do the reboot if it is the | ||
318 | correct CPU, otherwise it halts. */ | ||
319 | if (reboot_cpu != cpuid) | ||
320 | smp_call_function((void *)machine_restart , NULL, 1, 0); | ||
321 | } | ||
322 | |||
323 | /* if reboot_cpu is still -1, then we want a tradional reboot, | ||
324 | and if we are not running on the reboot_cpu,, halt */ | ||
325 | if ((reboot_cpu != -1) && (cpuid != reboot_cpu)) { | ||
326 | for (;;) | ||
327 | __asm__ __volatile__ ("hlt"); | ||
328 | } | ||
329 | /* | ||
330 | * Stop all CPUs and turn off local APICs and the IO-APIC, so | ||
331 | * other OSs see a clean IRQ state. | ||
332 | */ | ||
333 | smp_send_stop(); | ||
334 | #endif /* CONFIG_SMP */ | ||
335 | |||
336 | lapic_shutdown(); | ||
337 | |||
338 | #ifdef CONFIG_X86_IO_APIC | ||
339 | disable_IO_APIC(); | ||
340 | #endif | ||
341 | |||
342 | if (!reboot_thru_bios) { | ||
343 | if (efi_enabled) { | ||
344 | efi.reset_system(EFI_RESET_COLD, EFI_SUCCESS, 0, NULL); | ||
345 | __asm__ __volatile__("lidt %0": :"m" (no_idt)); | ||
346 | __asm__ __volatile__("int3"); | ||
347 | } | ||
348 | /* rebooting needs to touch the page at absolute addr 0 */ | ||
349 | *((unsigned short *)__va(0x472)) = reboot_mode; | ||
350 | for (;;) { | ||
351 | mach_reboot(); | ||
352 | /* That didn't work - force a triple fault.. */ | ||
353 | __asm__ __volatile__("lidt %0": :"m" (no_idt)); | ||
354 | __asm__ __volatile__("int3"); | ||
355 | } | ||
356 | } | ||
357 | if (efi_enabled) | ||
358 | efi.reset_system(EFI_RESET_WARM, EFI_SUCCESS, 0, NULL); | ||
359 | |||
360 | machine_real_restart(jump_to_bios, sizeof(jump_to_bios)); | ||
361 | } | ||
362 | |||
363 | EXPORT_SYMBOL(machine_restart); | ||
364 | |||
365 | void machine_halt(void) | ||
366 | { | ||
367 | } | ||
368 | |||
369 | EXPORT_SYMBOL(machine_halt); | ||
370 | |||
371 | void machine_power_off(void) | ||
372 | { | ||
373 | lapic_shutdown(); | ||
374 | |||
375 | if (efi_enabled) | ||
376 | efi.reset_system(EFI_RESET_SHUTDOWN, EFI_SUCCESS, 0, NULL); | ||
377 | if (pm_power_off) | ||
378 | pm_power_off(); | ||
379 | } | ||
380 | |||
381 | EXPORT_SYMBOL(machine_power_off); | ||
382 | |||