diff options
Diffstat (limited to 'arch/i386/boot/pm.c')
| -rw-r--r-- | arch/i386/boot/pm.c | 174 |
1 files changed, 0 insertions, 174 deletions
diff --git a/arch/i386/boot/pm.c b/arch/i386/boot/pm.c deleted file mode 100644 index 09fb342..0000000 --- a/arch/i386/boot/pm.c +++ /dev/null @@ -1,174 +0,0 @@ -/* -*- linux-c -*- ------------------------------------------------------- * - * - * Copyright (C) 1991, 1992 Linus Torvalds - * Copyright 2007 rPath, Inc. - All Rights Reserved - * - * This file is part of the Linux kernel, and is made available under - * the terms of the GNU General Public License version 2. - * - * ----------------------------------------------------------------------- */ - -/* - * arch/i386/boot/pm.c - * - * Prepare the machine for transition to protected mode. - */ - -#include "boot.h" -#include <asm/segment.h> - -/* - * Invoke the realmode switch hook if present; otherwise - * disable all interrupts. - */ -static void realmode_switch_hook(void) -{ - if (boot_params.hdr.realmode_swtch) { - asm volatile("lcallw *%0" - : : "m" (boot_params.hdr.realmode_swtch) - : "eax", "ebx", "ecx", "edx"); - } else { - asm volatile("cli"); - outb(0x80, 0x70); /* Disable NMI */ - io_delay(); - } -} - -/* - * A zImage kernel is loaded at 0x10000 but wants to run at 0x1000. - * A bzImage kernel is loaded and runs at 0x100000. - */ -static void move_kernel_around(void) -{ - /* Note: rely on the compile-time option here rather than - the LOADED_HIGH flag. The Qemu kernel loader unconditionally - sets the loadflags to zero. */ -#ifndef __BIG_KERNEL__ - u16 dst_seg, src_seg; - u32 syssize; - - dst_seg = 0x1000 >> 4; - src_seg = 0x10000 >> 4; - syssize = boot_params.hdr.syssize; /* Size in 16-byte paragraphs */ - - while (syssize) { - int paras = (syssize >= 0x1000) ? 0x1000 : syssize; - int dwords = paras << 2; - - asm volatile("pushw %%es ; " - "pushw %%ds ; " - "movw %1,%%es ; " - "movw %2,%%ds ; " - "xorw %%di,%%di ; " - "xorw %%si,%%si ; " - "rep;movsl ; " - "popw %%ds ; " - "popw %%es" - : "+c" (dwords) - : "r" (dst_seg), "r" (src_seg) - : "esi", "edi"); - - syssize -= paras; - dst_seg += paras; - src_seg += paras; - } -#endif -} - -/* - * Disable all interrupts at the legacy PIC. - */ -static void mask_all_interrupts(void) -{ - outb(0xff, 0xa1); /* Mask all interrupts on the secondary PIC */ - io_delay(); - outb(0xfb, 0x21); /* Mask all but cascade on the primary PIC */ - io_delay(); -} - -/* - * Reset IGNNE# if asserted in the FPU. - */ -static void reset_coprocessor(void) -{ - outb(0, 0xf0); - io_delay(); - outb(0, 0xf1); - io_delay(); -} - -/* - * Set up the GDT - */ -#define GDT_ENTRY(flags,base,limit) \ - (((u64)(base & 0xff000000) << 32) | \ - ((u64)flags << 40) | \ - ((u64)(limit & 0x00ff0000) << 32) | \ - ((u64)(base & 0x00ffff00) << 16) | \ - ((u64)(limit & 0x0000ffff))) - -struct gdt_ptr { - u16 len; - u32 ptr; -} __attribute__((packed)); - -static void setup_gdt(void) -{ - /* There are machines which are known to not boot with the GDT - being 8-byte unaligned. Intel recommends 16 byte alignment. */ - static const u64 boot_gdt[] __attribute__((aligned(16))) = { - /* CS: code, read/execute, 4 GB, base 0 */ - [GDT_ENTRY_BOOT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff), - /* DS: data, read/write, 4 GB, base 0 */ - [GDT_ENTRY_BOOT_DS] = GDT_ENTRY(0xc093, 0, 0xfffff), - }; - /* Xen HVM incorrectly stores a pointer to the gdt_ptr, instead - of the gdt_ptr contents. Thus, make it static so it will - stay in memory, at least long enough that we switch to the - proper kernel GDT. */ - static struct gdt_ptr gdt; - - gdt.len = sizeof(boot_gdt)-1; - gdt.ptr = (u32)&boot_gdt + (ds() << 4); - - asm volatile("lgdtl %0" : : "m" (gdt)); -} - -/* - * Set up the IDT - */ -static void setup_idt(void) -{ - static const struct gdt_ptr null_idt = {0, 0}; - asm volatile("lidtl %0" : : "m" (null_idt)); -} - -/* - * Actual invocation sequence - */ -void go_to_protected_mode(void) -{ - /* Hook before leaving real mode, also disables interrupts */ - realmode_switch_hook(); - - /* Move the kernel/setup to their final resting places */ - move_kernel_around(); - - /* Enable the A20 gate */ - if (enable_a20()) { - puts("A20 gate not responding, unable to boot...\n"); - die(); - } - - /* Reset coprocessor (IGNNE#) */ - reset_coprocessor(); - - /* Mask all interrupts in the PIC */ - mask_all_interrupts(); - - /* Actual transition to protected mode... */ - setup_idt(); - setup_gdt(); - protected_mode_jump(boot_params.hdr.code32_start, - (u32)&boot_params + (ds() << 4)); -} |
