--- /dev/null
+/******************************************************************************
+ * arch/x86/shutdown.c
+ *
+ * x86-specific shutdown handling.
+ */
+
+#include <xen/config.h>
+#include <xen/init.h>
+#include <xen/lib.h>
+#include <xen/sched.h>
+#include <xen/smp.h>
+#include <xen/delay.h>
+#include <xen/dmi.h>
+#include <asm/regs.h>
+#include <asm/mc146818rtc.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/processor.h>
+#include <asm/mpspec.h>
+#include <xen/irq.h>
+#include <xen/console.h>
+#include <asm/msr.h>
+
+/* opt_noreboot: If true, machine will need manual reset on error. */
+static int opt_noreboot = 0;
+boolean_param("noreboot", opt_noreboot);
+
+/* reboot_str: comma-separated list of reboot options. */
+static char __initdata reboot_str[10] = "";
+string_param("reboot", reboot_str);
+
+static long no_idt[2];
+static int reboot_mode;
+
+static inline void kb_wait(void)
+{
+ int i;
+
+ for ( i = 0; i < 0x10000; i++ )
+ if ( (inb_p(0x64) & 0x02) == 0 )
+ break;
+}
+
+void __attribute__((noreturn)) __machine_halt(void *unused)
+{
+ for ( ; ; )
+ safe_halt();
+}
+
+void machine_halt(void)
+{
+ watchdog_disable();
+ console_start_sync();
+ smp_call_function(__machine_halt, NULL, 1, 0);
+ __machine_halt(NULL);
+}
+
+#ifdef __i386__
+
+static int reboot_thru_bios;
+
+/* 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 const struct
+{
+ unsigned short size __attribute__ ((packed));
+ unsigned long long * base __attribute__ ((packed));
+}
+real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, real_mode_gdt_entries },
+real_mode_idt = { 0x3ff, NULL };
+
+
+/* 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 const unsigned char real_mode_switch [] =
+{
+ 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */
+ 0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */
+ 0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */
+ 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */
+ 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */
+ 0x0f, 0x20, 0xc2, /* movl %cr0,%edx */
+ 0x66, 0x81, 0xe2, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%edx */
+ 0x74, 0x02, /* jz f */
+ 0x0f, 0x09, /* wbinvd */
+ 0x24, 0x10, /* f: andb $0x10,al */
+ 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */
+};
+#define MAX_LENGTH 0x40
+static const unsigned char jump_to_bios [] =
+{
+ 0xea, 0xf0, 0xff, 0x00, 0xf0 /* ljmp $0xf000,$0xfff0 */
+};
+
+/*
+ * 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 MAX_LENGTH!
+ */
+void machine_real_restart(const unsigned char *code, unsigned 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. */
+
+ spin_lock(&rtc_lock);
+ CMOS_WRITE(0x00, 0x8f);
+ spin_unlock(&rtc_lock);
+
+ /* Identity-map virtual address zero. */
+
+ map_pages_to_xen(0, 0, 1, __PAGE_HYPERVISOR|MAP_SMALL_PAGES);
+ set_current(idle_vcpu[0]);
+ write_ptbase(idle_vcpu[0]);
+
+ /* 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 *)(PAGE_SIZE - sizeof(real_mode_switch) - MAX_LENGTH),
+ real_mode_switch, sizeof(real_mode_switch));
+ memcpy((void *)(PAGE_SIZE - MAX_LENGTH), code, length);
+
+ /* Set up the IDT for real mode. */
+
+ __asm__ __volatile__("lidt %0": : "m" (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. */
+
+ __asm__ __volatile__("lgdt %0": : "m" (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__ ("\tmov %0,%%ds\n"
+ "\tmov %0,%%es\n"
+ "\tmov %0,%%fs\n"
+ "\tmov %0,%%gs\n"
+ "\tmov %0,%%ss"
+ :
+ : "r" (0x0010));
+
+ /* 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 *)(PAGE_SIZE -
+ sizeof(real_mode_switch) -
+ MAX_LENGTH)));
+}
+
+#else /* __x86_64__ */
+
+#define machine_real_restart(x, y)
+#define reboot_thru_bios 0
+
+#endif
+
+void machine_restart(char * __unused)
+{
+ int i;
+
+ if ( opt_noreboot )
+ {
+ printk("Reboot disabled on cmdline: require manual reset\n");
+ machine_halt();
+ }
+
+ watchdog_disable();
+ console_start_sync();
+
+ local_irq_enable();
+
+ /* Ensure we are the boot CPU. */
+ if ( GET_APIC_ID(apic_read(APIC_ID)) != boot_cpu_physical_apicid )
+ {
+ smp_call_function((void *)machine_restart, NULL, 1, 0);
+ for ( ; ; )
+ safe_halt();
+ }
+
+ /*
+ * Stop all CPUs and turn off local APICs and the IO-APIC, so
+ * other OSs see a clean IRQ state.
+ */
+ smp_send_stop();
+ disable_IO_APIC();
+ hvm_disable();
+
+ /* Rebooting needs to touch the page at absolute address 0. */
+ *((unsigned short *)__va(0x472)) = reboot_mode;
+
+ if (reboot_thru_bios <= 0)
+ {
+ for ( ; ; )
+ {
+ /* Pulse the keyboard reset line. */
+ for ( i = 0; i < 100; i++ )
+ {
+ kb_wait();
+ udelay(50);
+ outb(0xfe,0x64); /* pulse reset low */
+ udelay(50);
+ }
+
+ /* That didn't work - force a triple fault.. */
+ __asm__ __volatile__("lidt %0": "=m" (no_idt));
+ __asm__ __volatile__("int3");
+ }
+ }
+ machine_real_restart(jump_to_bios, sizeof(jump_to_bios));
+}
+
+#ifndef reboot_thru_bios
+static int __init set_bios_reboot(struct dmi_system_id *d)
+{
+ if ( !reboot_thru_bios )
+ {
+ reboot_thru_bios = 1;
+ printk("%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 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 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"),
+ },
+ },
+ { }
+};
+#endif
+
+static int __init reboot_init(void)
+{
+ const char *str;
+
+ for ( str = reboot_str; *str != '\0'; str++ )
+ {
+ switch ( *str )
+ {
+ case 'n': /* no reboot */
+ opt_noreboot = 1;
+ break;
+ case 'w': /* "warm" reboot (no memory testing etc) */
+ reboot_mode = 0x1234;
+ break;
+ case 'c': /* "cold" reboot (with memory testing etc) */
+ reboot_mode = 0x0;
+ break;
+#ifndef reboot_thru_bios
+ case 'b': /* "bios" reboot by jumping through the BIOS */
+ reboot_thru_bios = 1;
+ break;
+ case 'h': /* "hard" reboot by toggling RESET and/or crashing the CPU */
+ reboot_thru_bios = -1;
+ break;
+#endif
+ }
+ if ( (str = strchr(str, ',')) == NULL )
+ break;
+ }
+
+#ifndef reboot_thru_bios
+ dmi_check_system(reboot_dmi_table);
+#endif
+ return 0;
+}
+__initcall(reboot_init);
projects / xen.git / commitdiff