Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/boot/head.S |
| 3 | * |
| 4 | * Copyright (C) 1991, 1992, 1993 Linus Torvalds |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 5 | */ |
| 6 | |
| 7 | /* |
| 8 | * head.S contains the 32-bit startup code. |
| 9 | * |
| 10 | * NOTE!!! Startup happens at absolute address 0x00001000, which is also where |
| 11 | * the page directory will exist. The startup code will be overwritten by |
| 12 | * the page directory. [According to comments etc elsewhere on a compressed |
| 13 | * kernel it will end up at 0x1000 + 1Mb I hope so as I assume this. - AC] |
| 14 | * |
| 15 | * Page 0 is deliberately kept safe, since System Management Mode code in |
| 16 | * laptops may need to access the BIOS data stored there. This is also |
| 17 | * useful for future device drivers that either access the BIOS via VM86 |
| 18 | * mode. |
| 19 | */ |
| 20 | |
| 21 | /* |
Domen Puncer | f454944 | 2005-06-25 14:58:59 -0700 | [diff] [blame] | 22 | * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | */ |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 24 | .code32 |
| 25 | .text |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | |
Tim Abbott | 1dc818c | 2009-09-16 16:44:27 -0400 | [diff] [blame] | 27 | #include <linux/init.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | #include <linux/linkage.h> |
| 29 | #include <asm/segment.h> |
Jeremy Fitzhardinge | 0341c14 | 2009-02-13 11:14:01 -0800 | [diff] [blame] | 30 | #include <asm/pgtable_types.h> |
| 31 | #include <asm/page_types.h> |
Alexander van Heukelum | 7c53976 | 2008-04-08 12:54:30 +0200 | [diff] [blame] | 32 | #include <asm/boot.h> |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 33 | #include <asm/msr.h> |
Cyrill Gorcunov | e83e31f4 | 2008-05-12 15:43:39 +0200 | [diff] [blame] | 34 | #include <asm/processor-flags.h> |
Eric W. Biederman | bd53147 | 2007-10-26 11:29:04 -0600 | [diff] [blame] | 35 | #include <asm/asm-offsets.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | |
Tim Abbott | 1dc818c | 2009-09-16 16:44:27 -0400 | [diff] [blame] | 37 | __HEAD |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | .code32 |
Cyrill Gorcunov | 2d4eeecb | 2009-02-14 00:50:22 +0300 | [diff] [blame] | 39 | ENTRY(startup_32) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | cld |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 41 | /* |
| 42 | * Test KEEP_SEGMENTS flag to see if the bootloader is asking |
| 43 | * us to not reload segments |
| 44 | */ |
Eric W. Biederman | bd53147 | 2007-10-26 11:29:04 -0600 | [diff] [blame] | 45 | testb $(1<<6), BP_loadflags(%esi) |
| 46 | jnz 1f |
| 47 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | cli |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 49 | movl $(__KERNEL_DS), %eax |
| 50 | movl %eax, %ds |
| 51 | movl %eax, %es |
| 52 | movl %eax, %ss |
Eric W. Biederman | bd53147 | 2007-10-26 11:29:04 -0600 | [diff] [blame] | 53 | 1: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 55 | /* |
| 56 | * Calculate the delta between where we were compiled to run |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 57 | * at and where we were actually loaded at. This can only be done |
| 58 | * with a short local call on x86. Nothing else will tell us what |
| 59 | * address we are running at. The reserved chunk of the real-mode |
H. Peter Anvin | 85414b6 | 2007-07-11 12:18:33 -0700 | [diff] [blame] | 60 | * data at 0x1e4 (defined as a scratch field) are used as the stack |
| 61 | * for this calculation. Only 4 bytes are needed. |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 62 | */ |
H. Peter Anvin | bd2a369 | 2009-05-05 23:24:50 -0700 | [diff] [blame] | 63 | leal (BP_scratch+4)(%esi), %esp |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 64 | call 1f |
| 65 | 1: popl %ebp |
| 66 | subl $1b, %ebp |
| 67 | |
Vivek Goyal | a4831e0 | 2007-05-02 19:27:08 +0200 | [diff] [blame] | 68 | /* setup a stack and make sure cpu supports long mode. */ |
Alexander van Heukelum | 7c53976 | 2008-04-08 12:54:30 +0200 | [diff] [blame] | 69 | movl $boot_stack_end, %eax |
Vivek Goyal | a4831e0 | 2007-05-02 19:27:08 +0200 | [diff] [blame] | 70 | addl %ebp, %eax |
| 71 | movl %eax, %esp |
| 72 | |
| 73 | call verify_cpu |
| 74 | testl %eax, %eax |
| 75 | jnz no_longmode |
| 76 | |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 77 | /* |
| 78 | * Compute the delta between where we were compiled to run at |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 79 | * and where the code will actually run at. |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 80 | * |
| 81 | * %ebp contains the address we are loaded at by the boot loader and %ebx |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 82 | * contains the address where we should move the kernel image temporarily |
| 83 | * for safe in-place decompression. |
| 84 | */ |
| 85 | |
| 86 | #ifdef CONFIG_RELOCATABLE |
| 87 | movl %ebp, %ebx |
H. Peter Anvin | 37ba7ab | 2009-05-11 15:56:08 -0700 | [diff] [blame] | 88 | movl BP_kernel_alignment(%esi), %eax |
| 89 | decl %eax |
| 90 | addl %eax, %ebx |
| 91 | notl %eax |
| 92 | andl %eax, %ebx |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 93 | #else |
H. Peter Anvin | 40b387a | 2009-05-11 14:41:55 -0700 | [diff] [blame] | 94 | movl $LOAD_PHYSICAL_ADDR, %ebx |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 95 | #endif |
| 96 | |
H. Peter Anvin | 02a884c | 2009-05-08 17:42:16 -0700 | [diff] [blame] | 97 | /* Target address to relocate to for decompression */ |
| 98 | addl $z_extract_offset, %ebx |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | |
| 100 | /* |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 101 | * Prepare for entering 64 bit mode |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | */ |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 103 | |
| 104 | /* Load new GDT with the 64bit segments using 32bit descriptor */ |
| 105 | leal gdt(%ebp), %eax |
| 106 | movl %eax, gdt+2(%ebp) |
| 107 | lgdt gdt(%ebp) |
| 108 | |
| 109 | /* Enable PAE mode */ |
Alexander Potashev | 4868402 | 2009-10-24 03:37:23 +0400 | [diff] [blame] | 110 | movl $(X86_CR4_PAE), %eax |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 111 | movl %eax, %cr4 |
| 112 | |
| 113 | /* |
| 114 | * Build early 4G boot pagetable |
| 115 | */ |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 116 | /* Initialize Page tables to 0 */ |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 117 | leal pgtable(%ebx), %edi |
| 118 | xorl %eax, %eax |
| 119 | movl $((4096*6)/4), %ecx |
| 120 | rep stosl |
| 121 | |
| 122 | /* Build Level 4 */ |
| 123 | leal pgtable + 0(%ebx), %edi |
| 124 | leal 0x1007 (%edi), %eax |
| 125 | movl %eax, 0(%edi) |
| 126 | |
| 127 | /* Build Level 3 */ |
| 128 | leal pgtable + 0x1000(%ebx), %edi |
| 129 | leal 0x1007(%edi), %eax |
| 130 | movl $4, %ecx |
| 131 | 1: movl %eax, 0x00(%edi) |
| 132 | addl $0x00001000, %eax |
| 133 | addl $8, %edi |
| 134 | decl %ecx |
| 135 | jnz 1b |
| 136 | |
| 137 | /* Build Level 2 */ |
| 138 | leal pgtable + 0x2000(%ebx), %edi |
| 139 | movl $0x00000183, %eax |
| 140 | movl $2048, %ecx |
| 141 | 1: movl %eax, 0(%edi) |
| 142 | addl $0x00200000, %eax |
| 143 | addl $8, %edi |
| 144 | decl %ecx |
| 145 | jnz 1b |
| 146 | |
| 147 | /* Enable the boot page tables */ |
| 148 | leal pgtable(%ebx), %eax |
| 149 | movl %eax, %cr3 |
| 150 | |
| 151 | /* Enable Long mode in EFER (Extended Feature Enable Register) */ |
| 152 | movl $MSR_EFER, %ecx |
| 153 | rdmsr |
| 154 | btsl $_EFER_LME, %eax |
| 155 | wrmsr |
| 156 | |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 157 | /* |
| 158 | * Setup for the jump to 64bit mode |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 159 | * |
| 160 | * When the jump is performend we will be in long mode but |
| 161 | * in 32bit compatibility mode with EFER.LME = 1, CS.L = 0, CS.D = 1 |
| 162 | * (and in turn EFER.LMA = 1). To jump into 64bit mode we use |
| 163 | * the new gdt/idt that has __KERNEL_CS with CS.L = 1. |
| 164 | * We place all of the values on our mini stack so lret can |
| 165 | * used to perform that far jump. |
| 166 | */ |
| 167 | pushl $__KERNEL_CS |
| 168 | leal startup_64(%ebp), %eax |
| 169 | pushl %eax |
| 170 | |
| 171 | /* Enter paged protected Mode, activating Long Mode */ |
Cyrill Gorcunov | e83e31f4 | 2008-05-12 15:43:39 +0200 | [diff] [blame] | 172 | movl $(X86_CR0_PG | X86_CR0_PE), %eax /* Enable Paging and Protected mode */ |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 173 | movl %eax, %cr0 |
| 174 | |
| 175 | /* Jump from 32bit compatibility mode into 64bit mode. */ |
| 176 | lret |
Cyrill Gorcunov | 2d4eeecb | 2009-02-14 00:50:22 +0300 | [diff] [blame] | 177 | ENDPROC(startup_32) |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 178 | |
Vivek Goyal | a4831e0 | 2007-05-02 19:27:08 +0200 | [diff] [blame] | 179 | no_longmode: |
| 180 | /* This isn't an x86-64 CPU so hang */ |
| 181 | 1: |
| 182 | hlt |
| 183 | jmp 1b |
| 184 | |
Kees Cook | c5cbac6 | 2010-11-10 10:35:51 -0800 | [diff] [blame] | 185 | #include "../../kernel/verify_cpu.S" |
Vivek Goyal | a4831e0 | 2007-05-02 19:27:08 +0200 | [diff] [blame] | 186 | |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 187 | /* |
| 188 | * Be careful here startup_64 needs to be at a predictable |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 189 | * address so I can export it in an ELF header. Bootloaders |
| 190 | * should look at the ELF header to find this address, as |
| 191 | * it may change in the future. |
| 192 | */ |
| 193 | .code64 |
Vivek Goyal | a4831e0 | 2007-05-02 19:27:08 +0200 | [diff] [blame] | 194 | .org 0x200 |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 195 | ENTRY(startup_64) |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 196 | /* |
| 197 | * We come here either from startup_32 or directly from a |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 198 | * 64bit bootloader. If we come here from a bootloader we depend on |
| 199 | * an identity mapped page table being provied that maps our |
| 200 | * entire text+data+bss and hopefully all of memory. |
| 201 | */ |
Matt Fleming | 291f363 | 2011-12-12 21:27:52 +0000 | [diff] [blame] | 202 | #ifdef CONFIG_EFI_STUB |
| 203 | pushq %rsi |
| 204 | mov %rcx, %rdi |
| 205 | mov %rdx, %rsi |
| 206 | call efi_main |
| 207 | popq %rsi |
| 208 | cmpq $0,%rax |
| 209 | je preferred_addr |
| 210 | movq %rax,%rsi |
| 211 | call 1f |
| 212 | 1: |
| 213 | popq %rax |
| 214 | subq $1b, %rax |
| 215 | subq BP_pref_address(%rsi), %rax |
| 216 | add BP_code32_start(%esi), %eax |
| 217 | leaq preferred_addr(%rax), %rax |
| 218 | jmp *%rax |
| 219 | |
| 220 | preferred_addr: |
| 221 | #endif |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 222 | |
| 223 | /* Setup data segments. */ |
| 224 | xorl %eax, %eax |
| 225 | movl %eax, %ds |
| 226 | movl %eax, %es |
| 227 | movl %eax, %ss |
Zachary Amsden | 08da5a2 | 2007-08-10 22:31:05 +0200 | [diff] [blame] | 228 | movl %eax, %fs |
| 229 | movl %eax, %gs |
| 230 | lldt %ax |
| 231 | movl $0x20, %eax |
| 232 | ltr %ax |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 233 | |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 234 | /* |
| 235 | * Compute the decompressed kernel start address. It is where |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 236 | * we were loaded at aligned to a 2M boundary. %rbp contains the |
| 237 | * decompressed kernel start address. |
| 238 | * |
| 239 | * If it is a relocatable kernel then decompress and run the kernel |
| 240 | * from load address aligned to 2MB addr, otherwise decompress and |
H. Peter Anvin | 40b387a | 2009-05-11 14:41:55 -0700 | [diff] [blame] | 241 | * run the kernel from LOAD_PHYSICAL_ADDR |
H. Peter Anvin | 02a884c | 2009-05-08 17:42:16 -0700 | [diff] [blame] | 242 | * |
| 243 | * We cannot rely on the calculation done in 32-bit mode, since we |
| 244 | * may have been invoked via the 64-bit entry point. |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 245 | */ |
| 246 | |
| 247 | /* Start with the delta to where the kernel will run at. */ |
| 248 | #ifdef CONFIG_RELOCATABLE |
| 249 | leaq startup_32(%rip) /* - $startup_32 */, %rbp |
H. Peter Anvin | 37ba7ab | 2009-05-11 15:56:08 -0700 | [diff] [blame] | 250 | movl BP_kernel_alignment(%rsi), %eax |
| 251 | decl %eax |
| 252 | addq %rax, %rbp |
| 253 | notq %rax |
| 254 | andq %rax, %rbp |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 255 | #else |
H. Peter Anvin | 40b387a | 2009-05-11 14:41:55 -0700 | [diff] [blame] | 256 | movq $LOAD_PHYSICAL_ADDR, %rbp |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 257 | #endif |
| 258 | |
H. Peter Anvin | 02a884c | 2009-05-08 17:42:16 -0700 | [diff] [blame] | 259 | /* Target address to relocate to for decompression */ |
| 260 | leaq z_extract_offset(%rbp), %rbx |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 261 | |
H. Peter Anvin | 0a13773 | 2009-05-08 16:27:41 -0700 | [diff] [blame] | 262 | /* Set up the stack */ |
| 263 | leaq boot_stack_end(%rbx), %rsp |
| 264 | |
| 265 | /* Zero EFLAGS */ |
| 266 | pushq $0 |
| 267 | popfq |
| 268 | |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 269 | /* |
| 270 | * Copy the compressed kernel to the end of our buffer |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 271 | * where decompression in place becomes safe. |
| 272 | */ |
H. Peter Anvin | 36d3793 | 2009-05-08 16:45:15 -0700 | [diff] [blame] | 273 | pushq %rsi |
| 274 | leaq (_bss-8)(%rip), %rsi |
| 275 | leaq (_bss-8)(%rbx), %rdi |
H. Peter Anvin | 5b11f1c | 2009-05-08 16:20:34 -0700 | [diff] [blame] | 276 | movq $_bss /* - $startup_32 */, %rcx |
H. Peter Anvin | 36d3793 | 2009-05-08 16:45:15 -0700 | [diff] [blame] | 277 | shrq $3, %rcx |
| 278 | std |
| 279 | rep movsq |
| 280 | cld |
| 281 | popq %rsi |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 282 | |
| 283 | /* |
| 284 | * Jump to the relocated address. |
| 285 | */ |
| 286 | leaq relocated(%rbx), %rax |
| 287 | jmp *%rax |
| 288 | |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 289 | .text |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 290 | relocated: |
| 291 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | /* |
H. Peter Anvin | 0a13773 | 2009-05-08 16:27:41 -0700 | [diff] [blame] | 293 | * Clear BSS (stack is currently empty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | */ |
H. Peter Anvin | 36d3793 | 2009-05-08 16:45:15 -0700 | [diff] [blame] | 295 | xorl %eax, %eax |
| 296 | leaq _bss(%rip), %rdi |
| 297 | leaq _ebss(%rip), %rcx |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 298 | subq %rdi, %rcx |
H. Peter Anvin | 36d3793 | 2009-05-08 16:45:15 -0700 | [diff] [blame] | 299 | shrq $3, %rcx |
| 300 | rep stosq |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 301 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | /* |
H. Peter Anvin | 22a57f5 | 2010-08-02 15:34:44 -0700 | [diff] [blame] | 303 | * Adjust our own GOT |
| 304 | */ |
| 305 | leaq _got(%rip), %rdx |
| 306 | leaq _egot(%rip), %rcx |
| 307 | 1: |
| 308 | cmpq %rcx, %rdx |
| 309 | jae 2f |
| 310 | addq %rbx, (%rdx) |
| 311 | addq $8, %rdx |
| 312 | jmp 1b |
| 313 | 2: |
| 314 | |
| 315 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | * Do the decompression, and jump to the new kernel.. |
| 317 | */ |
H. Peter Anvin | 02a884c | 2009-05-08 17:42:16 -0700 | [diff] [blame] | 318 | pushq %rsi /* Save the real mode argument */ |
| 319 | movq %rsi, %rdi /* real mode address */ |
| 320 | leaq boot_heap(%rip), %rsi /* malloc area for uncompression */ |
| 321 | leaq input_data(%rip), %rdx /* input_data */ |
| 322 | movl $z_input_len, %ecx /* input_len */ |
| 323 | movq %rbp, %r8 /* output target address */ |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 324 | call decompress_kernel |
| 325 | popq %rsi |
| 326 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 327 | /* |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 328 | * Jump to the decompressed kernel. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 329 | */ |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 330 | jmp *%rbp |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 331 | |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 332 | .data |
| 333 | gdt: |
| 334 | .word gdt_end - gdt |
| 335 | .long gdt |
| 336 | .word 0 |
| 337 | .quad 0x0000000000000000 /* NULL descriptor */ |
| 338 | .quad 0x00af9a000000ffff /* __KERNEL_CS */ |
| 339 | .quad 0x00cf92000000ffff /* __KERNEL_DS */ |
Zachary Amsden | 08da5a2 | 2007-08-10 22:31:05 +0200 | [diff] [blame] | 340 | .quad 0x0080890000000000 /* TS descriptor */ |
| 341 | .quad 0x0000000000000000 /* TS continued */ |
Vivek Goyal | 1ab60e0 | 2007-05-02 19:27:07 +0200 | [diff] [blame] | 342 | gdt_end: |
Alexander van Heukelum | 7c53976 | 2008-04-08 12:54:30 +0200 | [diff] [blame] | 343 | |
H. Peter Anvin | b40d68d | 2009-05-08 15:59:13 -0700 | [diff] [blame] | 344 | /* |
| 345 | * Stack and heap for uncompression |
| 346 | */ |
| 347 | .bss |
| 348 | .balign 4 |
Alexander van Heukelum | 7c53976 | 2008-04-08 12:54:30 +0200 | [diff] [blame] | 349 | boot_heap: |
| 350 | .fill BOOT_HEAP_SIZE, 1, 0 |
| 351 | boot_stack: |
| 352 | .fill BOOT_STACK_SIZE, 1, 0 |
| 353 | boot_stack_end: |
H. Peter Anvin | 5b11f1c | 2009-05-08 16:20:34 -0700 | [diff] [blame] | 354 | |
| 355 | /* |
| 356 | * Space for page tables (not in .bss so not zeroed) |
| 357 | */ |
| 358 | .section ".pgtable","a",@nobits |
| 359 | .balign 4096 |
| 360 | pgtable: |
| 361 | .fill 6*4096, 1, 0 |