removed unused macro for calling read_disk_raw

more simplification of push's

include/BIOS/func/ext_read.nasm

@@ -31,29 +31,6 @@ struc LBAPkt_t
     .lower_lba   resd 1
     .upper_lba   resd 1
 endstruc
-; call_read_disk_raw <word segment> <word offset> <dword lba> <word count> <word drive_num>
-%macro call_read_disk_raw 5
-    movzx ax, %5
-    push ax                                            ; drive_num
-
-    movzx ax, %4
-    push ax                                            ; count
-
-    movzx dword eax, %3
-    push dword eax                                     ; lba
-
-    movzx ax, %2
-    push ax                                            ; offset
-
-    movzx ax, %1
-    push ax                                            ; segment = 0
-
-    ; uint8_t read_stage2_raw(uint16_t buf_segment, uint16_t buf_offset, 
-    ;                         uint32_t lba,
-    ;                         uint16_t count, uint16_t drive_num)
-    call read_disk_raw
-    add sp, 0xC
-%endmacro
 
 ; Wrapper for AH=0x42 INT13h (Extended Read)
 ;
@@ -70,7 +47,6 @@ endstruc
 ; disk address packet's block count field set to number of blocks
 ; successfully transferred
 ;
-;
 ; uint8_t read_stage2_raw(uint16_t buf_segment, uint16_t buf_offset, 
 ;                         uint32_t lba,
 ;                         uint16_t count, uint8_t drive_num)
@@ -78,13 +54,10 @@ ALIGN 4, db 0x90
 read_disk_raw:
     __CDECL16_PROC_ENTRY
 .func:                         
-    mov ax, LBAPkt_t_size
-    push ax                 ; len
-    xor ax, ax
-    push ax                 ; val = 0
-    mov ax, lba_packet
-    push ax                 ; dest = lba_packet address
-    call kmemset        
+    push LBAPkt_t_size        ; len
+    push 0x00                 ; val = 0
+    push lba_packet           ; dest = lba_packet address
+    call kmemset              ; kmemset(dst, val, len)
     add sp, 0x06
 
     mov bx, lba_packet
@@ -97,7 +70,8 @@ read_disk_raw:
     mov dword [bx + LBAPkt_t.lower_lba], eax
 
     ; upper_lba is zero from kmemset
-    ; TODO: possiblly support >32bit LBA addresses in the future, this limits us to 4GiB
+    ; TODO: possiblly support >32bit LBA addresses in the future
+    ; this will limit us to (4GiB * sector size) of readable lba's from the disk
 
     mov ax, [bp + 6]
     mov word [bx + LBAPkt_t.offset], ax