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rulimine/stage1/gdt.asm

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Some work on ACPI and use EBDA start as end of usable conventional memory
2020-09-17 13:06:35 +03:00
gdt:
gpt: Embed stage2 code within GPT structures so an extra partition is not needed
2020-12-06 18:43:38 +03:00
dw .size - 1 + 8 ; GDT size
dd .start - 8 ; GDT start address
Enable A20 line and enter 'unreal mode' in the bootsect
2019-05-30 17:25:23 +03:00
Some work on ACPI and use EBDA start as end of usable conventional memory
2020-09-17 13:06:35 +03:00
.start:
; 32-bit code
dw 0xffff ; Limit
dw 0x0000 ; Base (low 16 bits)
db 0x00 ; Base (mid 8 bits)
stage1/gdt: Mark accessed flag in descriptors
2023-09-09 17:45:47 +03:00
db 10011011b ; Access
Some work on ACPI and use EBDA start as end of usable conventional memory
2020-09-17 13:06:35 +03:00
db 11001111b ; Granularity
db 0x00 ; Base (high 8 bits)
Enable A20 line and enter 'unreal mode' in the bootsect
2019-05-30 17:25:23 +03:00
Some work on ACPI and use EBDA start as end of usable conventional memory
2020-09-17 13:06:35 +03:00
; 32-bit data
dw 0xffff ; Limit
dw 0x0000 ; Base (low 16 bits)
db 0x00 ; Base (mid 8 bits)
stage1/gdt: Mark accessed flag in descriptors
2023-09-09 17:45:47 +03:00
db 10010011b ; Access
Some work on ACPI and use EBDA start as end of usable conventional memory
2020-09-17 13:06:35 +03:00
db 11001111b ; Granularity
db 0x00 ; Base (high 8 bits)
Enable A20 line and enter 'unreal mode' in the bootsect
2019-05-30 17:25:23 +03:00
Some work on ACPI and use EBDA start as end of usable conventional memory
2020-09-17 13:06:35 +03:00
.end:
elf: Add support for higher half kernels
2020-03-25 06:38:23 +03:00
Some work on ACPI and use EBDA start as end of usable conventional memory
2020-09-17 13:06:35 +03:00
.size: equ .end - .start