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Shorten boot assembly

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This commit is contained in:
Frans Kaashoek 2011-08-09 21:51:17 -04:00
parent 5460667c9c
commit 22c73411ca
1 changed files with 0 additions and 15 deletions
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15
multiboot.S
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@ -37,23 +37,8 @@ multiboot_header:
.long multiboot_entry .long multiboot_entry
# Multiboot entry point. Machine is mostly set up. # Multiboot entry point. Machine is mostly set up.
# Configure the GDT to match the environment that our usual
# boot loader - bootasm.S - sets up.
.globl multiboot_entry .globl multiboot_entry
multiboot_entry: multiboot_entry:
# lgdt V2P_WO(gdtdesc)
# ljmp $(SEG_KCODE<<3), $mbstart32
mbstart32:
# Set up the protected-mode data segment registers
movw $(SEG_KDATA<<3), %ax # Our data segment selector
movw %ax, %ds # -> DS: Data Segment
movw %ax, %es # -> ES: Extra Segment
movw %ax, %ss # -> SS: Stack Segment
movw $0, %ax # Zero segments not ready for use
movw %ax, %fs # -> FS
movw %ax, %gs # -> GS
movl $(V2P_WO(bootpgdir)), %eax movl $(V2P_WO(bootpgdir)), %eax
movl %eax, %cr3 movl %eax, %cr3
# Turn on paging. # Turn on paging.