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authorMiguel Boton <mboton.lkml@gmail.com>2008-01-30 07:32:51 -0500
committerIngo Molnar <mingo@elte.hu>2008-01-30 07:32:51 -0500
commit4d022e35fd7e07c522c7863fee6f07e53cf3fc14 (patch)
treeaae7e2633bd2808d812df652e00eb3e2ff4745d1 /arch/x86/kernel/reboot_32.c
parent71c339116a216b181fc5e203ef51a033fe5e38cf (diff)
x86: reboot_{32|64}.c unification
reboot_{32|64}.c unification patch. This patch unifies the code from the reboot_32.c and reboot_64.c files. It has been tested in computers with X86_32 and X86_64 kernels and it looks like all reboot modes work fine (EFI restart system hasn't been tested yet). Probably I made some mistakes (like I usually do) so I hope we can identify and fix them soon. Signed-off-by: Miguel Boton <mboton@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/kernel/reboot_32.c')
-rw-r--r--arch/x86/kernel/reboot_32.c413
1 files changed, 0 insertions, 413 deletions
diff --git a/arch/x86/kernel/reboot_32.c b/arch/x86/kernel/reboot_32.c
deleted file mode 100644
index c3376fae639d..000000000000
--- a/arch/x86/kernel/reboot_32.c
+++ /dev/null
@@ -1,413 +0,0 @@
1#include <linux/mm.h>
2#include <linux/module.h>
3#include <linux/delay.h>
4#include <linux/init.h>
5#include <linux/interrupt.h>
6#include <linux/mc146818rtc.h>
7#include <linux/efi.h>
8#include <linux/dmi.h>
9#include <linux/ctype.h>
10#include <linux/pm.h>
11#include <linux/reboot.h>
12#include <asm/uaccess.h>
13#include <asm/apic.h>
14#include <asm/hpet.h>
15#include <asm/desc.h>
16#include "mach_reboot.h"
17#include <asm/reboot_fixups.h>
18#include <asm/reboot.h>
19
20/*
21 * Power off function, if any
22 */
23void (*pm_power_off)(void);
24EXPORT_SYMBOL(pm_power_off);
25
26static int reboot_mode;
27static int reboot_thru_bios;
28
29#ifdef CONFIG_SMP
30static int reboot_cpu = -1;
31#endif
32static int __init reboot_setup(char *str)
33{
34 while(1) {
35 switch (*str) {
36 case 'w': /* "warm" reboot (no memory testing etc) */
37 reboot_mode = 0x1234;
38 break;
39 case 'c': /* "cold" reboot (with memory testing etc) */
40 reboot_mode = 0x0;
41 break;
42 case 'b': /* "bios" reboot by jumping through the BIOS */
43 reboot_thru_bios = 1;
44 break;
45 case 'h': /* "hard" reboot by toggling RESET and/or crashing the CPU */
46 reboot_thru_bios = 0;
47 break;
48#ifdef CONFIG_SMP
49 case 's': /* "smp" reboot by executing reset on BSP or other CPU*/
50 if (isdigit(*(str+1))) {
51 reboot_cpu = (int) (*(str+1) - '0');
52 if (isdigit(*(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 */
79static int __init set_bios_reboot(const 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
88static struct dmi_system_id __initdata reboot_dmi_table[] = {
89 { /* Handle problems with rebooting on Dell E520's */
90 .callback = set_bios_reboot,
91 .ident = "Dell E520",
92 .matches = {
93 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
94 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
95 },
96 },
97 { /* Handle problems with rebooting on Dell 1300's */
98 .callback = set_bios_reboot,
99 .ident = "Dell PowerEdge 1300",
100 .matches = {
101 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
102 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
103 },
104 },
105 { /* Handle problems with rebooting on Dell 300's */
106 .callback = set_bios_reboot,
107 .ident = "Dell PowerEdge 300",
108 .matches = {
109 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
110 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
111 },
112 },
113 { /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
114 .callback = set_bios_reboot,
115 .ident = "Dell OptiPlex 745",
116 .matches = {
117 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
118 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
119 DMI_MATCH(DMI_BOARD_NAME, "0WF810"),
120 },
121 },
122 { /* Handle problems with rebooting on Dell 2400's */
123 .callback = set_bios_reboot,
124 .ident = "Dell PowerEdge 2400",
125 .matches = {
126 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
127 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
128 },
129 },
130 { /* Handle problems with rebooting on HP laptops */
131 .callback = set_bios_reboot,
132 .ident = "HP Compaq Laptop",
133 .matches = {
134 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
135 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
136 },
137 },
138 { }
139};
140
141static int __init reboot_init(void)
142{
143 dmi_check_system(reboot_dmi_table);
144 return 0;
145}
146
147core_initcall(reboot_init);
148
149/* The following code and data reboots the machine by switching to real
150 mode and jumping to the BIOS reset entry point, as if the CPU has
151 really been reset. The previous version asked the keyboard
152 controller to pulse the CPU reset line, which is more thorough, but
153 doesn't work with at least one type of 486 motherboard. It is easy
154 to stop this code working; hence the copious comments. */
155
156static unsigned long long
157real_mode_gdt_entries [3] =
158{
159 0x0000000000000000ULL, /* Null descriptor */
160 0x00009a000000ffffULL, /* 16-bit real-mode 64k code at 0x00000000 */
161 0x000092000100ffffULL /* 16-bit real-mode 64k data at 0x00000100 */
162};
163
164static struct desc_ptr
165real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries },
166real_mode_idt = { 0x3ff, 0 },
167no_idt = { 0, 0 };
168
169
170/* This is 16-bit protected mode code to disable paging and the cache,
171 switch to real mode and jump to the BIOS reset code.
172
173 The instruction that switches to real mode by writing to CR0 must be
174 followed immediately by a far jump instruction, which set CS to a
175 valid value for real mode, and flushes the prefetch queue to avoid
176 running instructions that have already been decoded in protected
177 mode.
178
179 Clears all the flags except ET, especially PG (paging), PE
180 (protected-mode enable) and TS (task switch for coprocessor state
181 save). Flushes the TLB after paging has been disabled. Sets CD and
182 NW, to disable the cache on a 486, and invalidates the cache. This
183 is more like the state of a 486 after reset. I don't know if
184 something else should be done for other chips.
185
186 More could be done here to set up the registers as if a CPU reset had
187 occurred; hopefully real BIOSs don't assume much. */
188
189static unsigned char real_mode_switch [] =
190{
191 0x66, 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */
192 0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */
193 0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */
194 0x66, 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */
195 0x66, 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */
196 0x66, 0x0f, 0x20, 0xc3, /* movl %cr0,%ebx */
197 0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%ebx */
198 0x74, 0x02, /* jz f */
199 0x0f, 0x09, /* wbinvd */
200 0x24, 0x10, /* f: andb $0x10,al */
201 0x66, 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */
202};
203static unsigned char jump_to_bios [] =
204{
205 0xea, 0x00, 0x00, 0xff, 0xff /* ljmp $0xffff,$0x0000 */
206};
207
208/*
209 * Switch to real mode and then execute the code
210 * specified by the code and length parameters.
211 * We assume that length will aways be less that 100!
212 */
213void machine_real_restart(unsigned char *code, int length)
214{
215 local_irq_disable();
216
217 /* Write zero to CMOS register number 0x0f, which the BIOS POST
218 routine will recognize as telling it to do a proper reboot. (Well
219 that's what this book in front of me says -- it may only apply to
220 the Phoenix BIOS though, it's not clear). At the same time,
221 disable NMIs by setting the top bit in the CMOS address register,
222 as we're about to do peculiar things to the CPU. I'm not sure if
223 `outb_p' is needed instead of just `outb'. Use it to be on the
224 safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
225 */
226
227 spin_lock(&rtc_lock);
228 CMOS_WRITE(0x00, 0x8f);
229 spin_unlock(&rtc_lock);
230
231 /* Remap the kernel at virtual address zero, as well as offset zero
232 from the kernel segment. This assumes the kernel segment starts at
233 virtual address PAGE_OFFSET. */
234
235 memcpy (swapper_pg_dir, swapper_pg_dir + USER_PGD_PTRS,
236 sizeof (swapper_pg_dir [0]) * KERNEL_PGD_PTRS);
237
238 /*
239 * Use `swapper_pg_dir' as our page directory.
240 */
241 load_cr3(swapper_pg_dir);
242
243 /* Write 0x1234 to absolute memory location 0x472. The BIOS reads
244 this on booting to tell it to "Bypass memory test (also warm
245 boot)". This seems like a fairly standard thing that gets set by
246 REBOOT.COM programs, and the previous reset routine did this
247 too. */
248
249 *((unsigned short *)0x472) = reboot_mode;
250
251 /* For the switch to real mode, copy some code to low memory. It has
252 to be in the first 64k because it is running in 16-bit mode, and it
253 has to have the same physical and virtual address, because it turns
254 off paging. Copy it near the end of the first page, out of the way
255 of BIOS variables. */
256
257 memcpy ((void *) (0x1000 - sizeof (real_mode_switch) - 100),
258 real_mode_switch, sizeof (real_mode_switch));
259 memcpy ((void *) (0x1000 - 100), code, length);
260
261 /* Set up the IDT for real mode. */
262
263 load_idt(&real_mode_idt);
264
265 /* Set up a GDT from which we can load segment descriptors for real
266 mode. The GDT is not used in real mode; it is just needed here to
267 prepare the descriptors. */
268
269 load_gdt(&real_mode_gdt);
270
271 /* Load the data segment registers, and thus the descriptors ready for
272 real mode. The base address of each segment is 0x100, 16 times the
273 selector value being loaded here. This is so that the segment
274 registers don't have to be reloaded after switching to real mode:
275 the values are consistent for real mode operation already. */
276
277 __asm__ __volatile__ ("movl $0x0010,%%eax\n"
278 "\tmovl %%eax,%%ds\n"
279 "\tmovl %%eax,%%es\n"
280 "\tmovl %%eax,%%fs\n"
281 "\tmovl %%eax,%%gs\n"
282 "\tmovl %%eax,%%ss" : : : "eax");
283
284 /* Jump to the 16-bit code that we copied earlier. It disables paging
285 and the cache, switches to real mode, and jumps to the BIOS reset
286 entry point. */
287
288 __asm__ __volatile__ ("ljmp $0x0008,%0"
289 :
290 : "i" ((void *) (0x1000 - sizeof (real_mode_switch) - 100)));
291}
292#ifdef CONFIG_APM_MODULE
293EXPORT_SYMBOL(machine_real_restart);
294#endif
295
296static void native_machine_shutdown(void)
297{
298#ifdef CONFIG_SMP
299 int reboot_cpu_id;
300
301 /* The boot cpu is always logical cpu 0 */
302 reboot_cpu_id = 0;
303
304 /* See if there has been given a command line override */
305 if ((reboot_cpu != -1) && (reboot_cpu < NR_CPUS) &&
306 cpu_isset(reboot_cpu, cpu_online_map)) {
307 reboot_cpu_id = reboot_cpu;
308 }
309
310 /* Make certain the cpu I'm rebooting on is online */
311 if (!cpu_isset(reboot_cpu_id, cpu_online_map)) {
312 reboot_cpu_id = smp_processor_id();
313 }
314
315 /* Make certain I only run on the appropriate processor */
316 set_cpus_allowed(current, cpumask_of_cpu(reboot_cpu_id));
317
318 /* O.K. Now that I'm on the appropriate processor, stop
319 * all of the others, and disable their local APICs.
320 */
321
322 smp_send_stop();
323#endif /* CONFIG_SMP */
324
325 lapic_shutdown();
326
327#ifdef CONFIG_X86_IO_APIC
328 disable_IO_APIC();
329#endif
330#ifdef CONFIG_HPET_TIMER
331 hpet_disable();
332#endif
333}
334
335void __attribute__((weak)) mach_reboot_fixups(void)
336{
337}
338
339static void native_machine_emergency_restart(void)
340{
341 if (!reboot_thru_bios) {
342 if (efi_enabled) {
343 efi.reset_system(EFI_RESET_COLD, EFI_SUCCESS, 0, NULL);
344 load_idt(&no_idt);
345 __asm__ __volatile__("int3");
346 }
347 /* rebooting needs to touch the page at absolute addr 0 */
348 *((unsigned short *)__va(0x472)) = reboot_mode;
349 for (;;) {
350 mach_reboot_fixups(); /* for board specific fixups */
351 mach_reboot();
352 /* That didn't work - force a triple fault.. */
353 load_idt(&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
363static void native_machine_restart(char * __unused)
364{
365 machine_shutdown();
366 machine_emergency_restart();
367}
368
369static void native_machine_halt(void)
370{
371}
372
373static void native_machine_power_off(void)
374{
375 if (pm_power_off) {
376 machine_shutdown();
377 pm_power_off();
378 }
379}
380
381
382struct machine_ops machine_ops = {
383 .power_off = native_machine_power_off,
384 .shutdown = native_machine_shutdown,
385 .emergency_restart = native_machine_emergency_restart,
386 .restart = native_machine_restart,
387 .halt = native_machine_halt,
388};
389
390void machine_power_off(void)
391{
392 machine_ops.power_off();
393}
394
395void machine_shutdown(void)
396{
397 machine_ops.shutdown();
398}
399
400void machine_emergency_restart(void)
401{
402 machine_ops.emergency_restart();
403}
404
405void machine_restart(char *cmd)
406{
407 machine_ops.restart(cmd);
408}
409
410void machine_halt(void)
411{
412 machine_ops.halt();
413}
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