8daa12f7e0
* Add support for loading GDT on x86_64. * Add x86_64 assembly code to do the same as the x86_32 code. * Separate x86_32 and x86_64 code. Tested on qemu x86_32 and x86_64 using additional MTRRs. Tested on Lenovo T410 with additional x86_64 patches. Change-Id: I1c190627f5f0ed6f82738cb99423892382899d7b Signed-off-by: Patrick Rudolph <siro@das-labor.org> Reviewed-on: https://review.coreboot.org/c/coreboot/+/30500 Reviewed-by: Arthur Heymans <arthur@aheymans.xyz> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
54 lines
999 B
ArmAsm
54 lines
999 B
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
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.code32
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.section ".text._gdt_", "ax", @progbits
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.globl gdt_init
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gdt_init:
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lgdt %cs:gdtptr
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ret
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.previous
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.align 4
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.globl gdtptr
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gdtptr:
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.word gdt_end - gdt -1 /* compute the table limit */
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.long gdt /* we know the offset */
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#ifdef __x86_64__
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.code64
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.section ".text._gdt64_", "ax", @progbits
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.globl gdt_init64
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gdt_init64:
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lgdt gdtptr64
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ret
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.previous
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.align 4
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.globl gdtptr64
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gdtptr64:
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.word gdt_end - gdt -1 /* compute the table limit */
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.quad gdt /* we know the offset */
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#endif
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.align 4
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gdt:
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/* selgdt 0, unused */
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.word 0x0000, 0x0000 /* dummy */
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.byte 0x00, 0x00, 0x00, 0x00
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/* selgdt 0x08, flat code segment */
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.word 0xffff, 0x0000
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.byte 0x00, 0x9b, 0xcf, 0x00 /* G=1 and 0x0f, So we get 4Gbytes
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for limit */
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/* selgdt 0x10,flat data segment */
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.word 0xffff, 0x0000
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.byte 0x00, 0x93, 0xcf, 0x00
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/* selgdt 0x18, flat code segment (64-bit) */
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.word 0xffff, 0x0000
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.byte 0x00, 0x9b, 0xaf, 0x00
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gdt_end:
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