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-rw-r--r--arch/x86/kernel/reboot.c451
1 files changed, 451 insertions, 0 deletions
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
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index 000000000000..5818dc28167d
--- /dev/null
+++ b/arch/x86/kernel/reboot.c
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+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+#include <linux/pm.h>
+#include <linux/efi.h>
+#include <acpi/reboot.h>
+#include <asm/io.h>
+#include <asm/apic.h>
+#include <asm/desc.h>
+#include <asm/hpet.h>
+#include <asm/reboot_fixups.h>
+#include <asm/reboot.h>
+
+#ifdef CONFIG_X86_32
+# include <linux/dmi.h>
+# include <linux/ctype.h>
+# include <linux/mc146818rtc.h>
+# include <asm/pgtable.h>
+#else
+# include <asm/iommu.h>
+#endif
+
+/*
+ * Power off function, if any
+ */
+void (*pm_power_off)(void);
+EXPORT_SYMBOL(pm_power_off);
+
+static long no_idt[3];
+static int reboot_mode;
+enum reboot_type reboot_type = BOOT_KBD;
+int reboot_force;
+
+#if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
+static int reboot_cpu = -1;
+#endif
+
+/* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old]
+ warm Don't set the cold reboot flag
+ cold Set the cold reboot flag
+ bios Reboot by jumping through the BIOS (only for X86_32)
+ smp Reboot by executing reset on BSP or other CPU (only for X86_32)
+ triple Force a triple fault (init)
+ kbd Use the keyboard controller. cold reset (default)
+ acpi Use the RESET_REG in the FADT
+ efi Use efi reset_system runtime service
+ force Avoid anything that could hang.
+ */
+static int __init reboot_setup(char *str)
+{
+ for (;;) {
+ switch (*str) {
+ case 'w':
+ reboot_mode = 0x1234;
+ break;
+
+ case 'c':
+ reboot_mode = 0;
+ break;
+
+#ifdef CONFIG_X86_32
+#ifdef CONFIG_SMP
+ case 's':
+ if (isdigit(*(str+1))) {
+ reboot_cpu = (int) (*(str+1) - '0');
+ if (isdigit(*(str+2)))
+ reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
+ }
+ /* we will leave sorting out the final value
+ when we are ready to reboot, since we might not
+ have set up boot_cpu_id or smp_num_cpu */
+ break;
+#endif /* CONFIG_SMP */
+
+ case 'b':
+#endif
+ case 'a':
+ case 'k':
+ case 't':
+ case 'e':
+ reboot_type = *str;
+ break;
+
+ case 'f':
+ reboot_force = 1;
+ break;
+ }
+
+ str = strchr(str, ',');
+ if (str)
+ str++;
+ else
+ break;
+ }
+ return 1;
+}
+
+__setup("reboot=", reboot_setup);
+
+
+#ifdef CONFIG_X86_32
+/*
+ * Reboot options and system auto-detection code provided by
+ * Dell Inc. so their systems "just work". :-)
+ */
+
+/*
+ * Some machines require the "reboot=b" commandline option,
+ * this quirk makes that automatic.
+ */
+static int __init set_bios_reboot(const struct dmi_system_id *d)
+{
+ if (reboot_type != BOOT_BIOS) {
+ reboot_type = BOOT_BIOS;
+ printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
+ }
+ return 0;
+}
+
+static struct dmi_system_id __initdata reboot_dmi_table[] = {
+ { /* Handle problems with rebooting on Dell E520's */
+ .callback = set_bios_reboot,
+ .ident = "Dell E520",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
+ },
+ },
+ { /* Handle problems with rebooting on Dell 1300's */
+ .callback = set_bios_reboot,
+ .ident = "Dell PowerEdge 1300",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
+ },
+ },
+ { /* Handle problems with rebooting on Dell 300's */
+ .callback = set_bios_reboot,
+ .ident = "Dell PowerEdge 300",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
+ },
+ },
+ { /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
+ .callback = set_bios_reboot,
+ .ident = "Dell OptiPlex 745",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
+ DMI_MATCH(DMI_BOARD_NAME, "0WF810"),
+ },
+ },
+ { /* Handle problems with rebooting on Dell 2400's */
+ .callback = set_bios_reboot,
+ .ident = "Dell PowerEdge 2400",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
+ },
+ },
+ { /* Handle problems with rebooting on HP laptops */
+ .callback = set_bios_reboot,
+ .ident = "HP Compaq Laptop",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
+ },
+ },
+ { }
+};
+
+static int __init reboot_init(void)
+{
+ dmi_check_system(reboot_dmi_table);
+ return 0;
+}
+core_initcall(reboot_init);
+
+/* The following code and data reboots the machine by switching to real
+ mode and jumping to the BIOS reset entry point, as if the CPU has
+ really been reset. The previous version asked the keyboard
+ controller to pulse the CPU reset line, which is more thorough, but
+ doesn't work with at least one type of 486 motherboard. It is easy
+ to stop this code working; hence the copious comments. */
+static unsigned long long
+real_mode_gdt_entries [3] =
+{
+ 0x0000000000000000ULL, /* Null descriptor */
+ 0x00009a000000ffffULL, /* 16-bit real-mode 64k code at 0x00000000 */
+ 0x000092000100ffffULL /* 16-bit real-mode 64k data at 0x00000100 */
+};
+
+static struct desc_ptr
+real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries },
+real_mode_idt = { 0x3ff, 0 };
+
+/* This is 16-bit protected mode code to disable paging and the cache,
+ switch to real mode and jump to the BIOS reset code.
+
+ The instruction that switches to real mode by writing to CR0 must be
+ followed immediately by a far jump instruction, which set CS to a
+ valid value for real mode, and flushes the prefetch queue to avoid
+ running instructions that have already been decoded in protected
+ mode.
+
+ Clears all the flags except ET, especially PG (paging), PE
+ (protected-mode enable) and TS (task switch for coprocessor state
+ save). Flushes the TLB after paging has been disabled. Sets CD and
+ NW, to disable the cache on a 486, and invalidates the cache. This
+ is more like the state of a 486 after reset. I don't know if
+ something else should be done for other chips.
+
+ More could be done here to set up the registers as if a CPU reset had
+ occurred; hopefully real BIOSs don't assume much. */
+static unsigned char real_mode_switch [] =
+{
+ 0x66, 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */
+ 0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */
+ 0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */
+ 0x66, 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */
+ 0x66, 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */
+ 0x66, 0x0f, 0x20, 0xc3, /* movl %cr0,%ebx */
+ 0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%ebx */
+ 0x74, 0x02, /* jz f */
+ 0x0f, 0x09, /* wbinvd */
+ 0x24, 0x10, /* f: andb $0x10,al */
+ 0x66, 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */
+};
+static unsigned char jump_to_bios [] =
+{
+ 0xea, 0x00, 0x00, 0xff, 0xff /* ljmp $0xffff,$0x0000 */
+};
+
+/*
+ * Switch to real mode and then execute the code
+ * specified by the code and length parameters.
+ * We assume that length will aways be less that 100!
+ */
+void machine_real_restart(unsigned char *code, int length)
+{
+ local_irq_disable();
+
+ /* Write zero to CMOS register number 0x0f, which the BIOS POST
+ routine will recognize as telling it to do a proper reboot. (Well
+ that's what this book in front of me says -- it may only apply to
+ the Phoenix BIOS though, it's not clear). At the same time,
+ disable NMIs by setting the top bit in the CMOS address register,
+ as we're about to do peculiar things to the CPU. I'm not sure if
+ `outb_p' is needed instead of just `outb'. Use it to be on the
+ safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
+ */
+ spin_lock(&rtc_lock);
+ CMOS_WRITE(0x00, 0x8f);
+ spin_unlock(&rtc_lock);
+
+ /* Remap the kernel at virtual address zero, as well as offset zero
+ from the kernel segment. This assumes the kernel segment starts at
+ virtual address PAGE_OFFSET. */
+ memcpy(swapper_pg_dir, swapper_pg_dir + USER_PGD_PTRS,
+ sizeof(swapper_pg_dir [0]) * KERNEL_PGD_PTRS);
+
+ /*
+ * Use `swapper_pg_dir' as our page directory.
+ */
+ load_cr3(swapper_pg_dir);
+
+ /* Write 0x1234 to absolute memory location 0x472. The BIOS reads
+ this on booting to tell it to "Bypass memory test (also warm
+ boot)". This seems like a fairly standard thing that gets set by
+ REBOOT.COM programs, and the previous reset routine did this
+ too. */
+ *((unsigned short *)0x472) = reboot_mode;
+
+ /* For the switch to real mode, copy some code to low memory. It has
+ to be in the first 64k because it is running in 16-bit mode, and it
+ has to have the same physical and virtual address, because it turns
+ off paging. Copy it near the end of the first page, out of the way
+ of BIOS variables. */
+ memcpy((void *)(0x1000 - sizeof(real_mode_switch) - 100),
+ real_mode_switch, sizeof (real_mode_switch));
+ memcpy((void *)(0x1000 - 100), code, length);
+
+ /* Set up the IDT for real mode. */
+ load_idt(&real_mode_idt);
+
+ /* Set up a GDT from which we can load segment descriptors for real
+ mode. The GDT is not used in real mode; it is just needed here to
+ prepare the descriptors. */
+ load_gdt(&real_mode_gdt);
+
+ /* Load the data segment registers, and thus the descriptors ready for
+ real mode. The base address of each segment is 0x100, 16 times the
+ selector value being loaded here. This is so that the segment
+ registers don't have to be reloaded after switching to real mode:
+ the values are consistent for real mode operation already. */
+ __asm__ __volatile__ ("movl $0x0010,%%eax\n"
+ "\tmovl %%eax,%%ds\n"
+ "\tmovl %%eax,%%es\n"
+ "\tmovl %%eax,%%fs\n"
+ "\tmovl %%eax,%%gs\n"
+ "\tmovl %%eax,%%ss" : : : "eax");
+
+ /* Jump to the 16-bit code that we copied earlier. It disables paging
+ and the cache, switches to real mode, and jumps to the BIOS reset
+ entry point. */
+ __asm__ __volatile__ ("ljmp $0x0008,%0"
+ :
+ : "i" ((void *)(0x1000 - sizeof (real_mode_switch) - 100)));
+}
+#ifdef CONFIG_APM_MODULE
+EXPORT_SYMBOL(machine_real_restart);
+#endif
+
+#endif /* CONFIG_X86_32 */
+
+static inline void kb_wait(void)
+{
+ int i;
+
+ for (i = 0; i < 0x10000; i++) {
+ if ((inb(0x64) & 0x02) == 0)
+ break;
+ udelay(2);
+ }
+}
+
+void machine_emergency_restart(void)
+{
+ int i;
+
+ /* Tell the BIOS if we want cold or warm reboot */
+ *((unsigned short *)__va(0x472)) = reboot_mode;
+
+ for (;;) {
+ /* Could also try the reset bit in the Hammer NB */
+ switch (reboot_type) {
+ case BOOT_KBD:
+ for (i = 0; i < 10; i++) {
+ kb_wait();
+ udelay(50);
+ outb(0xfe, 0x64); /* pulse reset low */
+ udelay(50);
+ }
+
+ case BOOT_TRIPLE:
+ load_idt((const struct desc_ptr *)&no_idt);
+ __asm__ __volatile__("int3");
+
+ reboot_type = BOOT_KBD;
+ break;
+
+#ifdef CONFIG_X86_32
+ case BOOT_BIOS:
+ machine_real_restart(jump_to_bios, sizeof(jump_to_bios));
+
+ reboot_type = BOOT_KBD;
+ break;
+#endif
+
+ case BOOT_ACPI:
+ acpi_reboot();
+ reboot_type = BOOT_KBD;
+ break;
+
+
+ case BOOT_EFI:
+ if (efi_enabled)
+ efi.reset_system(reboot_mode ? EFI_RESET_WARM : EFI_RESET_COLD,
+ EFI_SUCCESS, 0, NULL);
+
+ reboot_type = BOOT_KBD;
+ break;
+ }
+ }
+}
+
+void machine_shutdown(void)
+{
+ /* Stop the cpus and apics */
+#ifdef CONFIG_SMP
+ int reboot_cpu_id;
+
+ /* The boot cpu is always logical cpu 0 */
+ reboot_cpu_id = 0;
+
+#ifdef CONFIG_X86_32
+ /* See if there has been given a command line override */
+ if ((reboot_cpu != -1) && (reboot_cpu < NR_CPUS) &&
+ cpu_isset(reboot_cpu, cpu_online_map))
+ reboot_cpu_id = reboot_cpu;
+#endif
+
+ /* Make certain the cpu I'm about to reboot on is online */
+ if (!cpu_isset(reboot_cpu_id, cpu_online_map))
+ reboot_cpu_id = smp_processor_id();
+
+ /* Make certain I only run on the appropriate processor */
+ set_cpus_allowed(current, cpumask_of_cpu(reboot_cpu_id));
+
+ /* O.K Now that I'm on the appropriate processor,
+ * stop all of the others.
+ */
+ smp_send_stop();
+#endif
+
+ lapic_shutdown();
+
+#ifdef CONFIG_X86_IO_APIC
+ disable_IO_APIC();
+#endif
+
+#ifdef CONFIG_HPET_TIMER
+ hpet_disable();
+#endif
+
+#ifdef CONFIG_X86_64
+ pci_iommu_shutdown();
+#endif
+}
+
+void machine_restart(char *__unused)
+{
+ printk("machine restart\n");
+
+ if (!reboot_force)
+ machine_shutdown();
+ machine_emergency_restart();
+}
+
+void machine_halt(void)
+{
+}
+
+void machine_power_off(void)
+{
+ if (pm_power_off) {
+ if (!reboot_force)
+ machine_shutdown();
+ pm_power_off();
+ }
+}
+
+struct machine_ops machine_ops = {
+ .power_off = machine_power_off,
+ .shutdown = machine_shutdown,
+ .emergency_restart = machine_emergency_restart,
+ .restart = machine_restart,
+ .halt = machine_halt
+};
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