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base: karlos:43a0d9017c380bf3320ae5cb2d62a792422b0736
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karlos:main
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compare: karlos:b8a175b78fff3fa765bdbfb95f728029049d6ad4
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karlos:main

4 commits
43a0d9017c ... b8a175b78f

Author SHA1 Message Date
Thomas Oltmann
b8a175b78f Setting up a VESA video mode 2025-07-16 04:45:32 +02:00
Thomas Oltmann
cdfef627fa Printing a hex dump of the tftp_open cmd 2025-07-09 20:22:39 +02:00
Thomas Oltmann
093969301e Trying to debug failing TFTP open 2025-07-09 19:29:27 +02:00
Thomas Oltmann
be2d14de91 Increased TX buffer size 2025-07-09 18:49:38 +02:00
1 changed files with 247 additions and 25 deletions
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272
lboot.S
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@ -22,6 +22,7 @@
.code16
.set PACKET_SIZE, 512
.set TX_BUF_SIZE, 4096
.macro pxe_call, opcode
push %eax
@ -38,7 +39,8 @@
lcall *pxe_api
add $6, %sp
or %ss:(%bx), %ax
mov %ss:(%bx), %cx
or %cx, %ax
jnz _pcerr
pop %edx
@ -57,6 +59,8 @@ _start: cli
call init_com1
mov $msg_start, %si
call print
mov $msg_start, %si
call print
@ -76,6 +80,20 @@ _start: cli
call print
call enable_a20
.set PXE_GET_CACHED_INFO, 0x0071
push $0
push %cs
push $tx_buf
push $TX_BUF_SIZE
push $2
push $0
pxe_call PXE_GET_CACHED_INFO
add $12, %sp
mov tx_buf+20, %eax
mov %eax, server_ip
mov tx_buf+24, %eax
mov %eax, gateway_ip
mov $msg_unreal, %si
call print
call unreal
@ -92,26 +110,19 @@ _start: cli
call print
call paging
.set PXE_GET_CACHED_INFO, 0x0071
push $0
push %cs
push $tx_buf
push $PACKET_SIZE
push $2
push $0
pxe_call PXE_GET_CACHED_INFO
add $12, %sp
mov tx_buf+20, %eax
mov %eax, server_ip
mov $msg_read, %si
call print
mov $fn_initrd, %esi
call read_file
mov %ebx, bb_ird_ptr
mov $msg_vbe, %si
call print
call vbe_setup
mov $msg_long, %si
call print
jmp hang // REMOVE ME
call long
jmp hang
@ -321,19 +332,40 @@ tftp_open: push %ecx
push %bp
mov %sp, %bp
mov %esi, %ebx
mov $msg_topen, %si
call print
push $PACKET_SIZE
push $69<<8
mov $128, %ecx
sub %cx, %sp
sub %cx, %sp
mov %ss, %edi
shl $4, %edi
add %esp, %edi
xor %ax, %ax
cld
addr32 rep stosb
mov %ebx, %esi
mov $6, %ecx
mov %ss, %edi
shl $4, %edi
add %esp, %edi
cld
addr32 rep movsb
push $0
push $0
push gateway_ip+2
push gateway_ip
push server_ip+2
push server_ip
push $0
mov %ss, %esi
shl $4, %esi
add %esp, %esi
mov $128, %ecx
call dump
pxe_call PXE_TFTP_OPEN
leave
@ -346,6 +378,9 @@ tftp_open: push %ecx
tftp_close: push %bp
mov %sp, %bp
mov $msg_tclose, %si
call print
push $0
pxe_call PXE_TFTP_CLOSE
@ -357,6 +392,9 @@ tftp_read: push %ebx
push %bp
mov %sp, %bp
mov $msg_tread, %si
call print
push %cs
push $tx_buf
push $0
@ -375,25 +413,201 @@ out_of_mem: mov $msg_memerr, %si
jmp hang
// print: print NUL-terminated string pointed to by SI
print: xor %bx, %bx
print: push %eax
push %si
push %bp
mov %sp, %bp
1: lodsb
or %al, %al
jz 2f
call printch
jmp 1b
2: leave
pop %si
pop %eax
ret
_prnext: mov $COM1+5, %dx
printch: push %eax
push %ebx
push %edx
push %ebp
mov %ax, %bx
1: mov $COM1+5, %dx
inb %dx, %al
test $0x20, %al
jz _prnext
jz 1b
lodsb
or %al, %al
jz _prdone
mov %bx, %ax
mov $COM1, %dx
outb %al, %dx
xor %bx, %bx
mov $0x0E, %ah
int $0x10
jmp _prnext
_prdone: ret
pop %ebp
pop %edx
pop %ebx
pop %eax
ret
dump: push %eax
push %ebx
push %ecx
push %edx
push %esi
push %bp
mov %sp, %bp
xor %dx, %dx
1: cmp %cx, %dx
jae 2f
inc %dx
addr32 lodsb
push %ax
mov %al, %bl
shr $4, %bx
and $0x0F, %bx
mov hex_digits(%bx), %al
call printch
pop %bx
and $0x0F, %bx
mov hex_digits(%bx), %al
call printch
mov $' ', %al
call printch
test $0xF, %dx
jnz 1b
mov $'\r', %al
call printch
mov $'\n', %al
call printch
jmp 1b
2: mov $'\r', %al
call printch
mov $'\n', %al
call printch
leave
pop %esi
pop %edx
pop %ecx
pop %ebx
pop %eax
ret
vbe_setup:
push %ecx
push %esi
push %bp
mov %sp, %bp
call vbe_getinfo
mov vbe_info+14, %si
mov vbe_info+16, %cx
mov %cx, %fs
_vbenext: mov %fs:(%si), %cx
add $2, %si
cmp $0xFFFF, %cx
je _vbedone
call vbe_getmode
testw $0x80, tx_buf
jz _vbenext
mov %cx, %bx
and $0x0FFF, %bx
or $0x4000, %bx
call vbe_setmode
jmp _vbedone
_vbedone:
leave
pop %esi
pop %ecx
ret
vbe_getinfo:
push %eax
push %edi
push %bp
mov %sp, %bp
mov $0x4F00, %ax
mov $vbe_info, %di
int $0x10
cmp $0x4F, %ax
je 1f
mov $msg_vbeerr, %si
call print
jmp hang
1:
cmpl $0x41534556, vbe_info // "VESA"
je 1f
mov $msg_vbeerr, %si
call print
jmp hang
1: leave
pop %edi
pop %eax
ret
vbe_getmode:
push %eax
push %edi
push %bp
mov %sp, %bp
mov $0x4F01, %ax
mov $tx_buf, %di
int $0x10
cmp $0x4F, %ax
je 1f
mov $msg_vbeerr, %si
call print
jmp hang
1: leave
pop %edi
pop %eax
ret
vbe_setmode:
push %eax
push %bp
mov %sp, %bp
mov $0x4F02, %ax
int $0x10
cmp $0x4F, %ax
je 1f
mov $msg_vbeerr, %si
call print
jmp hang
1: leave
pop %eax
ret
vbe_info:
.ascii "VBE2"
.skip 512 - 4
// long: Enter long mode
long:
@ -491,15 +705,21 @@ msg_getmap: .asciz " * Memory Map\r\n"
msg_mkheap: .asciz " * Making Space\r\n"
msg_paging: .asciz " * Paging\r\n"
msg_read: .asciz " * Retrieving\r\n"
msg_vbe: .asciz " * Framebuffer\r\n"
msg_long: .asciz " * Long Mode\r\n"
msg_pserr: .asciz "panic: Missing !PXE structure.\r\n"
msg_pcerr: .asciz "panic: PXE call failed.\r\n"
msg_vbeerr: .asciz "panic: VBE call failed.\r\n"
msg_memerr: .asciz "panic: Out of heap space.\r\n"
msg_topen: .asciz "tftp_open\r\n"
msg_tclose: .asciz "tftp_close\r\n"
msg_tread: .asciz "tftp_read\r\n"
fn_initrd: .asciz "initrd"
pxe_api: .long 0
server_ip: .space 4
gateway_ip: .space 4
heap_ptr: .long 0
heap_end: .long 0
@ -513,7 +733,7 @@ pml4_ptr: .long 0
// Points to the end of the memory map
memmap_end: .short 0
tx_buf: .space PACKET_SIZE
tx_buf: .space TX_BUF_SIZE
.code64
// trampo64: Trampoline function to load long-mode segments
@ -579,6 +799,8 @@ type_table: .byte 0
// - Sanitizing the memmap
// - Parsing a config file
hex_digits: .ascii "0123456789ABCDEF"
.section .data.bootboot
bootboot: .ascii "BOOT"
bb_size: .long 128