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1/*
2 * linux/boot/head.S
3 *
4 * Copyright (C) 1991, 1992, 1993 Linus Torvalds
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/*
22 * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
23 */
24 .code32
25 .text
26
27#include <linux/init.h>
28#include <linux/linkage.h>
29#include <asm/segment.h>
30#include <asm/pgtable_types.h>
31#include <asm/page_types.h>
32#include <asm/boot.h>
33#include <asm/msr.h>
34#include <asm/processor-flags.h>
35#include <asm/asm-offsets.h>
36
37 __HEAD
38 .code32
39ENTRY(startup_32)
40 cld
41 /*
42 * Test KEEP_SEGMENTS flag to see if the bootloader is asking
43 * us to not reload segments
44 */
45 testb $(1<<6), BP_loadflags(%esi)
46 jnz 1f
47
48 cli
49 movl $(__KERNEL_DS), %eax
50 movl %eax, %ds
51 movl %eax, %es
52 movl %eax, %ss
531:
54
55/*
56 * Calculate the delta between where we were compiled to run
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
60 * data at 0x1e4 (defined as a scratch field) are used as the stack
61 * for this calculation. Only 4 bytes are needed.
62 */
63 leal (BP_scratch+4)(%esi), %esp
64 call 1f
651: popl %ebp
66 subl $1b, %ebp
67
68/* setup a stack and make sure cpu supports long mode. */
69 movl $boot_stack_end, %eax
70 addl %ebp, %eax
71 movl %eax, %esp
72
73 call verify_cpu
74 testl %eax, %eax
75 jnz no_longmode
76
77/*
78 * Compute the delta between where we were compiled to run at
79 * and where the code will actually run at.
80 *
81 * %ebp contains the address we are loaded at by the boot loader and %ebx
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
88 movl BP_kernel_alignment(%esi), %eax
89 decl %eax
90 addl %eax, %ebx
91 notl %eax
92 andl %eax, %ebx
93#else
94 movl $LOAD_PHYSICAL_ADDR, %ebx
95#endif
96
97 /* Target address to relocate to for decompression */
98 addl $z_extract_offset, %ebx
99
100/*
101 * Prepare for entering 64 bit mode
102 */
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 */
110 movl $(X86_CR4_PAE), %eax
111 movl %eax, %cr4
112
113 /*
114 * Build early 4G boot pagetable
115 */
116 /* Initialize Page tables to 0 */
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
1311: 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
1411: 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
157 /*
158 * Setup for the jump to 64bit mode
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 */
172 movl $(X86_CR0_PG | X86_CR0_PE), %eax /* Enable Paging and Protected mode */
173 movl %eax, %cr0
174
175 /* Jump from 32bit compatibility mode into 64bit mode. */
176 lret
177ENDPROC(startup_32)
178
179no_longmode:
180 /* This isn't an x86-64 CPU so hang */
1811:
182 hlt
183 jmp 1b
184
185#include "../../kernel/verify_cpu.S"
186
187 /*
188 * Be careful here startup_64 needs to be at a predictable
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
194 .org 0x200
195ENTRY(startup_64)
196 /*
197 * We come here either from startup_32 or directly from a
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 */
202
203 /* Setup data segments. */
204 xorl %eax, %eax
205 movl %eax, %ds
206 movl %eax, %es
207 movl %eax, %ss
208 movl %eax, %fs
209 movl %eax, %gs
210 lldt %ax
211 movl $0x20, %eax
212 ltr %ax
213
214 /*
215 * Compute the decompressed kernel start address. It is where
216 * we were loaded at aligned to a 2M boundary. %rbp contains the
217 * decompressed kernel start address.
218 *
219 * If it is a relocatable kernel then decompress and run the kernel
220 * from load address aligned to 2MB addr, otherwise decompress and
221 * run the kernel from LOAD_PHYSICAL_ADDR
222 *
223 * We cannot rely on the calculation done in 32-bit mode, since we
224 * may have been invoked via the 64-bit entry point.
225 */
226
227 /* Start with the delta to where the kernel will run at. */
228#ifdef CONFIG_RELOCATABLE
229 leaq startup_32(%rip) /* - $startup_32 */, %rbp
230 movl BP_kernel_alignment(%rsi), %eax
231 decl %eax
232 addq %rax, %rbp
233 notq %rax
234 andq %rax, %rbp
235#else
236 movq $LOAD_PHYSICAL_ADDR, %rbp
237#endif
238
239 /* Target address to relocate to for decompression */
240 leaq z_extract_offset(%rbp), %rbx
241
242 /* Set up the stack */
243 leaq boot_stack_end(%rbx), %rsp
244
245 /* Zero EFLAGS */
246 pushq $0
247 popfq
248
249/*
250 * Copy the compressed kernel to the end of our buffer
251 * where decompression in place becomes safe.
252 */
253 pushq %rsi
254 leaq (_bss-8)(%rip), %rsi
255 leaq (_bss-8)(%rbx), %rdi
256 movq $_bss /* - $startup_32 */, %rcx
257 shrq $3, %rcx
258 std
259 rep movsq
260 cld
261 popq %rsi
262
263/*
264 * Jump to the relocated address.
265 */
266 leaq relocated(%rbx), %rax
267 jmp *%rax
268
269 .text
270relocated:
271
272/*
273 * Clear BSS (stack is currently empty)
274 */
275 xorl %eax, %eax
276 leaq _bss(%rip), %rdi
277 leaq _ebss(%rip), %rcx
278 subq %rdi, %rcx
279 shrq $3, %rcx
280 rep stosq
281
282/*
283 * Adjust our own GOT
284 */
285 leaq _got(%rip), %rdx
286 leaq _egot(%rip), %rcx
2871:
288 cmpq %rcx, %rdx
289 jae 2f
290 addq %rbx, (%rdx)
291 addq $8, %rdx
292 jmp 1b
2932:
294
295/*
296 * Do the decompression, and jump to the new kernel..
297 */
298 pushq %rsi /* Save the real mode argument */
299 movq %rsi, %rdi /* real mode address */
300 leaq boot_heap(%rip), %rsi /* malloc area for uncompression */
301 leaq input_data(%rip), %rdx /* input_data */
302 movl $z_input_len, %ecx /* input_len */
303 movq %rbp, %r8 /* output target address */
304 call decompress_kernel
305 popq %rsi
306
307/*
308 * Jump to the decompressed kernel.
309 */
310 jmp *%rbp
311
312 .data
313gdt:
314 .word gdt_end - gdt
315 .long gdt
316 .word 0
317 .quad 0x0000000000000000 /* NULL descriptor */
318 .quad 0x00af9a000000ffff /* __KERNEL_CS */
319 .quad 0x00cf92000000ffff /* __KERNEL_DS */
320 .quad 0x0080890000000000 /* TS descriptor */
321 .quad 0x0000000000000000 /* TS continued */
322gdt_end:
323
324/*
325 * Stack and heap for uncompression
326 */
327 .bss
328 .balign 4
329boot_heap:
330 .fill BOOT_HEAP_SIZE, 1, 0
331boot_stack:
332 .fill BOOT_STACK_SIZE, 1, 0
333boot_stack_end:
334
335/*
336 * Space for page tables (not in .bss so not zeroed)
337 */
338 .section ".pgtable","a",@nobits
339 .balign 4096
340pgtable:
341 .fill 6*4096, 1, 0
1/*
2 * linux/boot/head.S
3 *
4 * Copyright (C) 1991, 1992, 1993 Linus Torvalds
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/*
22 * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
23 */
24 .code32
25 .text
26
27#include <linux/init.h>
28#include <linux/linkage.h>
29#include <asm/segment.h>
30#include <asm/boot.h>
31#include <asm/msr.h>
32#include <asm/processor-flags.h>
33#include <asm/asm-offsets.h>
34#include <asm/bootparam.h>
35
36/*
37 * Locally defined symbols should be marked hidden:
38 */
39 .hidden _bss
40 .hidden _ebss
41 .hidden _got
42 .hidden _egot
43
44 __HEAD
45 .code32
46ENTRY(startup_32)
47 /*
48 * 32bit entry is 0 and it is ABI so immutable!
49 * If we come here directly from a bootloader,
50 * kernel(text+data+bss+brk) ramdisk, zero_page, command line
51 * all need to be under the 4G limit.
52 */
53 cld
54 /*
55 * Test KEEP_SEGMENTS flag to see if the bootloader is asking
56 * us to not reload segments
57 */
58 testb $KEEP_SEGMENTS, BP_loadflags(%esi)
59 jnz 1f
60
61 cli
62 movl $(__BOOT_DS), %eax
63 movl %eax, %ds
64 movl %eax, %es
65 movl %eax, %ss
661:
67
68/*
69 * Calculate the delta between where we were compiled to run
70 * at and where we were actually loaded at. This can only be done
71 * with a short local call on x86. Nothing else will tell us what
72 * address we are running at. The reserved chunk of the real-mode
73 * data at 0x1e4 (defined as a scratch field) are used as the stack
74 * for this calculation. Only 4 bytes are needed.
75 */
76 leal (BP_scratch+4)(%esi), %esp
77 call 1f
781: popl %ebp
79 subl $1b, %ebp
80
81/* setup a stack and make sure cpu supports long mode. */
82 movl $boot_stack_end, %eax
83 addl %ebp, %eax
84 movl %eax, %esp
85
86 call verify_cpu
87 testl %eax, %eax
88 jnz no_longmode
89
90/*
91 * Compute the delta between where we were compiled to run at
92 * and where the code will actually run at.
93 *
94 * %ebp contains the address we are loaded at by the boot loader and %ebx
95 * contains the address where we should move the kernel image temporarily
96 * for safe in-place decompression.
97 */
98
99#ifdef CONFIG_RELOCATABLE
100 movl %ebp, %ebx
101 movl BP_kernel_alignment(%esi), %eax
102 decl %eax
103 addl %eax, %ebx
104 notl %eax
105 andl %eax, %ebx
106 cmpl $LOAD_PHYSICAL_ADDR, %ebx
107 jge 1f
108#endif
109 movl $LOAD_PHYSICAL_ADDR, %ebx
1101:
111
112 /* Target address to relocate to for decompression */
113 addl $z_extract_offset, %ebx
114
115/*
116 * Prepare for entering 64 bit mode
117 */
118
119 /* Load new GDT with the 64bit segments using 32bit descriptor */
120 leal gdt(%ebp), %eax
121 movl %eax, gdt+2(%ebp)
122 lgdt gdt(%ebp)
123
124 /* Enable PAE mode */
125 movl %cr4, %eax
126 orl $X86_CR4_PAE, %eax
127 movl %eax, %cr4
128
129 /*
130 * Build early 4G boot pagetable
131 */
132 /* Initialize Page tables to 0 */
133 leal pgtable(%ebx), %edi
134 xorl %eax, %eax
135 movl $((4096*6)/4), %ecx
136 rep stosl
137
138 /* Build Level 4 */
139 leal pgtable + 0(%ebx), %edi
140 leal 0x1007 (%edi), %eax
141 movl %eax, 0(%edi)
142
143 /* Build Level 3 */
144 leal pgtable + 0x1000(%ebx), %edi
145 leal 0x1007(%edi), %eax
146 movl $4, %ecx
1471: movl %eax, 0x00(%edi)
148 addl $0x00001000, %eax
149 addl $8, %edi
150 decl %ecx
151 jnz 1b
152
153 /* Build Level 2 */
154 leal pgtable + 0x2000(%ebx), %edi
155 movl $0x00000183, %eax
156 movl $2048, %ecx
1571: movl %eax, 0(%edi)
158 addl $0x00200000, %eax
159 addl $8, %edi
160 decl %ecx
161 jnz 1b
162
163 /* Enable the boot page tables */
164 leal pgtable(%ebx), %eax
165 movl %eax, %cr3
166
167 /* Enable Long mode in EFER (Extended Feature Enable Register) */
168 movl $MSR_EFER, %ecx
169 rdmsr
170 btsl $_EFER_LME, %eax
171 wrmsr
172
173 /* After gdt is loaded */
174 xorl %eax, %eax
175 lldt %ax
176 movl $__BOOT_TSS, %eax
177 ltr %ax
178
179 /*
180 * Setup for the jump to 64bit mode
181 *
182 * When the jump is performend we will be in long mode but
183 * in 32bit compatibility mode with EFER.LME = 1, CS.L = 0, CS.D = 1
184 * (and in turn EFER.LMA = 1). To jump into 64bit mode we use
185 * the new gdt/idt that has __KERNEL_CS with CS.L = 1.
186 * We place all of the values on our mini stack so lret can
187 * used to perform that far jump.
188 */
189 pushl $__KERNEL_CS
190 leal startup_64(%ebp), %eax
191#ifdef CONFIG_EFI_MIXED
192 movl efi32_config(%ebp), %ebx
193 cmp $0, %ebx
194 jz 1f
195 leal handover_entry(%ebp), %eax
1961:
197#endif
198 pushl %eax
199
200 /* Enter paged protected Mode, activating Long Mode */
201 movl $(X86_CR0_PG | X86_CR0_PE), %eax /* Enable Paging and Protected mode */
202 movl %eax, %cr0
203
204 /* Jump from 32bit compatibility mode into 64bit mode. */
205 lret
206ENDPROC(startup_32)
207
208#ifdef CONFIG_EFI_MIXED
209 .org 0x190
210ENTRY(efi32_stub_entry)
211 add $0x4, %esp /* Discard return address */
212 popl %ecx
213 popl %edx
214 popl %esi
215
216 leal (BP_scratch+4)(%esi), %esp
217 call 1f
2181: pop %ebp
219 subl $1b, %ebp
220
221 movl %ecx, efi32_config(%ebp)
222 movl %edx, efi32_config+8(%ebp)
223 sgdtl efi32_boot_gdt(%ebp)
224
225 leal efi32_config(%ebp), %eax
226 movl %eax, efi_config(%ebp)
227
228 jmp startup_32
229ENDPROC(efi32_stub_entry)
230#endif
231
232 .code64
233 .org 0x200
234ENTRY(startup_64)
235 /*
236 * 64bit entry is 0x200 and it is ABI so immutable!
237 * We come here either from startup_32 or directly from a
238 * 64bit bootloader.
239 * If we come here from a bootloader, kernel(text+data+bss+brk),
240 * ramdisk, zero_page, command line could be above 4G.
241 * We depend on an identity mapped page table being provided
242 * that maps our entire kernel(text+data+bss+brk), zero page
243 * and command line.
244 */
245#ifdef CONFIG_EFI_STUB
246 /*
247 * The entry point for the PE/COFF executable is efi_pe_entry, so
248 * only legacy boot loaders will execute this jmp.
249 */
250 jmp preferred_addr
251
252ENTRY(efi_pe_entry)
253 movq %rcx, efi64_config(%rip) /* Handle */
254 movq %rdx, efi64_config+8(%rip) /* EFI System table pointer */
255
256 leaq efi64_config(%rip), %rax
257 movq %rax, efi_config(%rip)
258
259 call 1f
2601: popq %rbp
261 subq $1b, %rbp
262
263 /*
264 * Relocate efi_config->call().
265 */
266 addq %rbp, efi64_config+88(%rip)
267
268 movq %rax, %rdi
269 call make_boot_params
270 cmpq $0,%rax
271 je fail
272 mov %rax, %rsi
273 leaq startup_32(%rip), %rax
274 movl %eax, BP_code32_start(%rsi)
275 jmp 2f /* Skip the relocation */
276
277handover_entry:
278 call 1f
2791: popq %rbp
280 subq $1b, %rbp
281
282 /*
283 * Relocate efi_config->call().
284 */
285 movq efi_config(%rip), %rax
286 addq %rbp, 88(%rax)
2872:
288 movq efi_config(%rip), %rdi
289 call efi_main
290 movq %rax,%rsi
291 cmpq $0,%rax
292 jne 2f
293fail:
294 /* EFI init failed, so hang. */
295 hlt
296 jmp fail
2972:
298 movl BP_code32_start(%esi), %eax
299 leaq preferred_addr(%rax), %rax
300 jmp *%rax
301
302preferred_addr:
303#endif
304
305 /* Setup data segments. */
306 xorl %eax, %eax
307 movl %eax, %ds
308 movl %eax, %es
309 movl %eax, %ss
310 movl %eax, %fs
311 movl %eax, %gs
312
313 /*
314 * Compute the decompressed kernel start address. It is where
315 * we were loaded at aligned to a 2M boundary. %rbp contains the
316 * decompressed kernel start address.
317 *
318 * If it is a relocatable kernel then decompress and run the kernel
319 * from load address aligned to 2MB addr, otherwise decompress and
320 * run the kernel from LOAD_PHYSICAL_ADDR
321 *
322 * We cannot rely on the calculation done in 32-bit mode, since we
323 * may have been invoked via the 64-bit entry point.
324 */
325
326 /* Start with the delta to where the kernel will run at. */
327#ifdef CONFIG_RELOCATABLE
328 leaq startup_32(%rip) /* - $startup_32 */, %rbp
329 movl BP_kernel_alignment(%rsi), %eax
330 decl %eax
331 addq %rax, %rbp
332 notq %rax
333 andq %rax, %rbp
334 cmpq $LOAD_PHYSICAL_ADDR, %rbp
335 jge 1f
336#endif
337 movq $LOAD_PHYSICAL_ADDR, %rbp
3381:
339
340 /* Target address to relocate to for decompression */
341 leaq z_extract_offset(%rbp), %rbx
342
343 /* Set up the stack */
344 leaq boot_stack_end(%rbx), %rsp
345
346 /* Zero EFLAGS */
347 pushq $0
348 popfq
349
350/*
351 * Copy the compressed kernel to the end of our buffer
352 * where decompression in place becomes safe.
353 */
354 pushq %rsi
355 leaq (_bss-8)(%rip), %rsi
356 leaq (_bss-8)(%rbx), %rdi
357 movq $_bss /* - $startup_32 */, %rcx
358 shrq $3, %rcx
359 std
360 rep movsq
361 cld
362 popq %rsi
363
364/*
365 * Jump to the relocated address.
366 */
367 leaq relocated(%rbx), %rax
368 jmp *%rax
369
370#ifdef CONFIG_EFI_STUB
371 .org 0x390
372ENTRY(efi64_stub_entry)
373 movq %rdi, efi64_config(%rip) /* Handle */
374 movq %rsi, efi64_config+8(%rip) /* EFI System table pointer */
375
376 leaq efi64_config(%rip), %rax
377 movq %rax, efi_config(%rip)
378
379 movq %rdx, %rsi
380 jmp handover_entry
381ENDPROC(efi64_stub_entry)
382#endif
383
384 .text
385relocated:
386
387/*
388 * Clear BSS (stack is currently empty)
389 */
390 xorl %eax, %eax
391 leaq _bss(%rip), %rdi
392 leaq _ebss(%rip), %rcx
393 subq %rdi, %rcx
394 shrq $3, %rcx
395 rep stosq
396
397/*
398 * Adjust our own GOT
399 */
400 leaq _got(%rip), %rdx
401 leaq _egot(%rip), %rcx
4021:
403 cmpq %rcx, %rdx
404 jae 2f
405 addq %rbx, (%rdx)
406 addq $8, %rdx
407 jmp 1b
4082:
409
410/*
411 * Do the decompression, and jump to the new kernel..
412 */
413 pushq %rsi /* Save the real mode argument */
414 movq $z_run_size, %r9 /* size of kernel with .bss and .brk */
415 pushq %r9
416 movq %rsi, %rdi /* real mode address */
417 leaq boot_heap(%rip), %rsi /* malloc area for uncompression */
418 leaq input_data(%rip), %rdx /* input_data */
419 movl $z_input_len, %ecx /* input_len */
420 movq %rbp, %r8 /* output target address */
421 movq $z_output_len, %r9 /* decompressed length, end of relocs */
422 call decompress_kernel /* returns kernel location in %rax */
423 popq %r9
424 popq %rsi
425
426/*
427 * Jump to the decompressed kernel.
428 */
429 jmp *%rax
430
431 .code32
432no_longmode:
433 /* This isn't an x86-64 CPU so hang */
4341:
435 hlt
436 jmp 1b
437
438#include "../../kernel/verify_cpu.S"
439
440 .data
441gdt:
442 .word gdt_end - gdt
443 .long gdt
444 .word 0
445 .quad 0x0000000000000000 /* NULL descriptor */
446 .quad 0x00af9a000000ffff /* __KERNEL_CS */
447 .quad 0x00cf92000000ffff /* __KERNEL_DS */
448 .quad 0x0080890000000000 /* TS descriptor */
449 .quad 0x0000000000000000 /* TS continued */
450gdt_end:
451
452#ifdef CONFIG_EFI_STUB
453efi_config:
454 .quad 0
455
456#ifdef CONFIG_EFI_MIXED
457 .global efi32_config
458efi32_config:
459 .fill 11,8,0
460 .quad efi64_thunk
461 .byte 0
462#endif
463
464 .global efi64_config
465efi64_config:
466 .fill 11,8,0
467 .quad efi_call
468 .byte 1
469#endif /* CONFIG_EFI_STUB */
470
471/*
472 * Stack and heap for uncompression
473 */
474 .bss
475 .balign 4
476boot_heap:
477 .fill BOOT_HEAP_SIZE, 1, 0
478boot_stack:
479 .fill BOOT_STACK_SIZE, 1, 0
480boot_stack_end:
481
482/*
483 * Space for page tables (not in .bss so not zeroed)
484 */
485 .section ".pgtable","a",@nobits
486 .balign 4096
487pgtable:
488 .fill 6*4096, 1, 0