; $Id$
; ****************************************************************************
;
-; pxelinux.asm
+; isolinux.asm
;
-; A program to boot Linux kernels off a TFTP server using the Intel PXE
-; network booting API. It is based on the SYSLINUX boot loader for
-; MS-DOS floppies.
+; A program to boot Linux kernels off a CD-ROM using the El Torito
+; boot standard in "no emulation" mode, making the entire filesystem
+; available. It is based on the SYSLINUX boot loader for MS-DOS
+; floppies.
;
; Copyright (C) 1994-2001 H. Peter Anvin
;
;
; ****************************************************************************
-
-%include "pxe.inc"
-
-;
-; Macros for byte order of constants
-;
-%define htons(x) ( ( ((x) & 0FFh) << 8 ) + ( ((x) & 0FF00h) >> 8 ) )
-%define ntohs(x) htons(x)
-%define htonl(x) ( ( ((x) & 0FFh) << 24) + ( ((x) & 0FF00h) << 8 ) + ( ((x) & 0FF0000h) >> 8 ) + ( ((x) & 0FF000000h) >> 24) )
-%define ntohl(x) htonl(x)
+; NOTE TO SELF: Based on pxelinux.asm,v 1.48 2001/03/30 02:52:17 hpa
+; Integrate PXELINUX changes since that version, please
;
; Some semi-configurable constants... change on your own risk. Most are imposed
; by the kernel.
;
max_cmd_len equ 255 ; Must be odd; 255 is the kernel limit
-FILENAME_MAX_LG2 equ 5 ; log2(Max filename size Including final null)
+FILENAME_MAX_LG2 equ 6 ; log2(Max filename size Including final null)
FILENAME_MAX equ (1 << FILENAME_MAX_LG2)
-REBOOT_TIME equ 5*60 ; If failure, time until full reset
HIGHMEM_MAX equ 038000000h ; Highest address for an initrd
HIGHMEM_SLOP equ 128*1024 ; Avoid this much memory near the top
DEFAULT_BAUD equ 9600 ; Default baud rate for serial port
BAUD_DIVISOR equ 115200 ; Serial port parameter
-MAX_SOCKETS_LG2 equ 6 ; log2(Max number of open sockets)
-MAX_SOCKETS equ (1 << MAX_SOCKETS_LG2)
-TFTP_PORT equ htons(69) ; Default TFTP port
-PKT_RETRY equ 6 ; Packet transmit retry count
-PKT_TIMEOUT equ 8 ; Initial timeout, timer ticks @ 55 ms
-TFTP_BLOCKSIZE_LG2 equ 9 ; log2(bytes/block)
-TFTP_BLOCKSIZE equ (1 << TFTP_BLOCKSIZE_LG2)
-
-;
-; TFTP operation codes
-;
-TFTP_RRQ equ htons(1) ; Read request
-TFTP_WRQ equ htons(2) ; Write request
-TFTP_DATA equ htons(3) ; Data packet
-TFTP_ACK equ htons(4) ; ACK packet
-TFTP_ERROR equ htons(5) ; ERROR packet
-TFTP_OACK equ htons(6) ; OACK packet
+MAX_OPEN_LG2 equ 6 ; log2(Max number of open files)
+MAX_OPEN equ (1 << MAX_OPEN_LG2)
;
; Should be updated with every release to avoid bootsector/SYS file mismatch
;
; ID for SYSLINUX (reported to kernel)
;
-syslinux_id equ 032h ; SYSLINUX (3) 2 = PXELINUX
+syslinux_id equ 033h ; SYSLINUX (3) 3 = ISOLINUX
+
;
; Segments used by Linux
;
-; Note: the real_mode_seg is supposed to be 9000h, but PXE uses that
-; memory. Therefore, we load it at 5000:0000h and copy it before starting
-; the Linux kernel.
-;
real_mode_seg equ 5000h
fake_setup_seg equ real_mode_seg+020h
comboot_seg equ 2000h ; COMBOOT image loading zone
;
-; BOOTP/DHCP packet pattern
-;
- struc bootp_t
-bootp:
-.opcode resb 1 ; BOOTP/DHCP "opcode"
-.hardware resb 1 ; ARP hardware type
-.hardlen resb 1 ; Hardware address length
-.gatehops resb 1 ; Used by forwarders
-.ident resd 1 ; Transaction ID
-.seconds resw 1 ; Seconds elapsed
-.flags resw 1 ; Broadcast flags
-.cip resd 1 ; Client IP
-.yip resd 1 ; "Your" IP
-.sip resd 1 ; Next server IP
-.gip resd 1 ; Relay agent IP
-.macaddr resb 16 ; Client MAC address
-.sname resb 64 ; Server name (optional)
-.bootfile resb 128 ; Boot file name
-.option_magic resd 1 ; Vendor option magic cookie
-.options resb 1260 ; Vendor options
- endstruc
-
-BOOTP_OPTION_MAGIC equ htonl(0x63825363) ; See RFC 2132
-
-;
-; TFTP connection data structure. Each one of these corresponds to a local
-; UDP port. The size of this structure must be a power of 2.
-;
- struc tftp_port_t
-tftp_localport resw 1 ; Local port number (0 = not in use)
-tftp_remoteport resw 1 ; Remote port number
-tftp_remoteip resd 1 ; Remote IP address
-tftp_filepos resd 1 ; Position within file
-tftp_filesize resd 1 ; Total file size
+; File structure. This holds the information for each currently open file.
+;
+ struc open_file_t
+file_sector resd 1 ; Sector pointer (0 = structure free)
+file_sectors resd 1 ; Number of sectors left
endstruc
-%if (tftp_port_t_size & (tftp_port_t_size-1))
-%error "tftp_port_t is not a power of 2"
+%if (open_file_t_size & (open_file_t_size-1))
+%error "open_file_t is not a power of 2"
%endif
;
FuncFlag resb 1 ; == 1 if <Ctrl-F> pressed
OverLoad resb 1 ; Set if DHCP packet uses "overloading"
- alignb tftp_port_t_size
-Sockets resb MAX_SOCKETS*tftp_port_t_size
-
- alignb 16
- ; BOOTP/DHCP packet buffer
-
- alignb 16
-packet_buf resb 2048 ; Transfer packet
-packet_buf_size equ $-packet_buf
+ alignb open_file_t_size
+Files resb MAX_OPEN*open_file_t_size
section .text
org 7C00h
+;;
+;; Primary entry point. Because BIOSes are buggy, we only load the first
+;; CD-ROM sector (2K) of the file, so the number one priority is actually
+;; loading the rest.
+;;
+bootsec equ $
+_start: ; Far jump makes sure we canonicalize the address
+ cli ; 1 byte
+ jmp 0:_start1 ; 5 bytes
+ nop
+ nop
+
+ ; This table gets filled in by mkisofs using the
+ ; -boot-info-table option
+bi_pvd: dd 0xdeadbeef ; LBA of primary volume descriptor
+bi_file: dd 0xdeadbeef ; LBA of boot file
+bi_length: dd 0xdeadbeef ; Length of boot file
+bi_csum: dd 0xdeadbeef ; Checksum of boot file
+bi_reserved: times 10 dd 0xdeadbeef ; Reserved
+
+_start1: xor ax,ax
+ mov es,ax
+ mov ss,ax
+ mov ds,ax
+ mov sp,_start ; Set up stack
+ sti
+
+ cld
+ ;
+ ; Before modifying any memory, get the checksum of bytes 64-2048
+ ;
+initial_csum: xor edi,edi
+ mov si,_start1
+ mov cx,(2048-64) >> 2
+.loop: lodsd
+ add edi,eax
+ loop .loop
+ mov [FirstSecSum],edi
+
+ ; Set up boot file sizes
+ mov eax,[bi_length]
+ sub eax,2048-3
+ shr eax,2 ; bytes->dwords
+ mov [ImageDwords],eax ; boot file dwords
+ add eax,(2047 >> 2)
+ shr eax,9 ; dwords->sectors
+ mov [ImageSectors],ax ; boot file sectors
+
+ mov si,startup_msg
+ call writemsg
+ mov [DriveNo],dl
+ mov al,dl
+ call writehex2
+ call crlf
+
+ ; Now figure out what we're actually doing
+ ; Note: use passed-in DL value rather than 7Fh because
+ ; at least some BIOSes will get the wrong value otherwise
+ mov ax,4B01h ; Get disk emulation status
+ mov dl,[DriveNo]
+ mov si,spec_packet
+ int 13h
+ jc near spec_query_failed ; Shouldn't happen (BIOS bug)
+ mov dl,[DriveNo]
+ cmp [sp_drive],dl ; Should contain the drive number
+ jne near spec_query_failed
+
+ mov si,spec_ok_msg
+ call writemsg
+ mov al,byte [sp_drive]
+ call writehex2
+ call crlf
+
+found_drive:
+ ; Get drive information
+ mov ah,48h
+ mov dl,[DriveNo]
+ mov si,drive_params
+ int 13h
+ jnc params_ok
+
+ mov si,nosecsize_msg
+ call writemsg
+
+params_ok:
+ ; Check for the sector size (should be 2048, but
+ ; some BIOSes apparently think we're 512-byte media)
+ mov si,secsize_msg
+ call writemsg
+ mov ax,[dp_secsize]
+ mov [bdib_secsize],ax
+ call writehex4
+ call crlf
+
+load_image:
+ ; Some BIOSes apparently have limitations on the size
+ ; that may be loaded (despite the El Torito spec being very
+ ; clear on the fact that it must all be loaded.) Therefore,
+ ; we load it ourselves, and *bleep* the BIOS.
+
+ mov eax,[bi_file] ; Address of code to load
+ inc eax ; Don't reload bootstrap code
+ mov si,offset_msg
+ call writemsg
+ call writehex8
+ call crlf
+
+ ; Just in case some BIOSes have problems with
+ ; segment wraparound, use the normalized address
+ mov bx,(REALOFF >> 4)
+ mov es,bx
+ xor bx,bx
+ mov bp,[ImageSectors]
+ push ax
+ mov si,size_msg
+ call writemsg
+ mov ax,bp
+ call writehex4
+ call crlf
+ pop ax
+ call getlinsec_cdrom
+
+ mov ax,ds
+ mov es,ax
+
+ mov si,loaded_msg
+ call writemsg
+
+ ; Verify the checksum on the loaded image.
+verify_image:
+ mov si,REALOFF
+ mov bx,es
+ mov ecx,[ImageDwords]
+ mov edi,[FirstSecSum] ; First sector checksum
+.loop es lodsd
+ add edi,eax
+ dec ecx
+ jz .done
+ and si,si
+ jnz .loop
+ ; SI wrapped around, advance ES
+ add bx,1000h
+ mov es,bx
+ jmp short .loop
+.done: mov ax,ds
+ mov es,ax
+ cmp [bi_csum],edi
+ je integrity_ok
+
+ mov si,checkerr_msg
+ call writestr
+
+integrity_ok:
+ ; Copy relevant data to BDIB
+ movzx ax,byte [sp_drive]
+ mov [bdib_unit],ax
+ mov ebx,[bi_pvd]
+ mov [bdib_offset],ebx
+
+ ; Now point to the BDIB and run
+ mov bx,bdib ; Set up BDIB pointer in ES:BX
+
+ mov si,ready_msg
+ call writemsg
+
+ jmp all_read ; Jump to main code
+
+ ; INT 13h, AX=4B01h, DL=7Fh failed. Try to scan the entire 80h-FFh from
+ ; the end.
+spec_query_failed:
+ mov si,spec_err_msg
+ call writemsg
+
+ mov dl,0FFh
+.test_loop: pusha
+ mov ax,4B01h
+ mov si,spec_packet
+ mov byte [si],13 ; Size of buffer
+ int 13h
+ popa
+ jc .still_broken
+
+ mov si,maybe_msg
+ call writemsg
+ mov al,dl
+ call writehex2
+ call crlf
+
+ cmp byte [sp_drive],dl
+ jne .still_broken
+
+ ; Okay, good enough...
+ mov si,alright_msg
+ call writemsg
+ mov [DriveNo],dl
+ jmp found_drive
+
+.still_broken: dec dx
+ cmp dl, 80h
+ jnb .test_loop
+
+fatal_error:
+ mov si,nothing_msg
+ call writemsg
+
+.norge: jmp short .norge
+
+ ; Information message (DS:SI) output
+ ; Prefix with "isoboot: "; first byte is flag if
+ ; we should set the pause in bdib_flags
+writemsg: push ax
+ push si
+ mov si,isoboot_str
+ call writestr
+ pop si
+ lodsb
+ or [bdib_flags],al
+ call writestr
+ pop ax
+ ret
+
+ ; Information string (DS:SI) output
+writestr: pushad
+ pushfd
+.loop: lodsb
+ and al,al
+ jz .done
+ mov ah,0Eh
+ int 10h
+ jmp short .loop
+.done: popfd
+ popad
+ ret
+
+ ; Write value in AL, AX or EAX as hex
+writehex2: pushad
+ mov cx,2
+ shl eax,24
+ jmp short writehex_common
+writehex4: pushad
+ mov cx,4
+ shl eax,16
+ jmp short writehex_common
+writehex8: pushad
+ mov cx,8
+writehex_common:
+ pushfd
+ mov bx,hex_table
+.loop: rol eax,4 ; Move bits in question into bottom bits
+ push eax
+ and al,0Fh
+ xlatb
+ mov ah,0Eh
+ int 10h
+ pop eax
+ loop .loop
+ popfd
+ popad
+ ret
+
+ ; Print newline
+crlf: push si
+ mov si,crlf_str
+ call writestr
+ pop si
+ ret
+
;
-; Primary entry point.
+; Get linear sectors - EBIOS LBA addressing, 2048-byte sectors.
;
-bootsec equ $
-_start:
- jmp 0:_start1 ; Canonicalize address
-_start1:
+; Note that we can't always do this as a single request, because at least
+; Phoenix BIOSes has a 127-sector limit. To be on the safe side, stick
+; to 32 sectors (64K) per request.
+;
+getlinsec_cdrom:
+ mov si,dapa ; Load up the DAPA
+ mov [si+4],bx
+ mov bx,es
+ mov [si+6],bx
+ mov [si+8],eax
+.loop:
+ push bp ; Sectors left
+ cmp bp,byte 32
+ jbe .bp_ok
+ mov bp,32
+.bp_ok:
+ mov [si+2],bp
+ push si
+ mov dl,[DriveNo]
+ mov ah,42h ; Extended Read
+ call xint13
+ pop si
+ pop bp
+ movzx eax,word [si+2] ; Sectors we read
+ add [si+8],eax ; Advance sector pointer
+ sub bp,ax ; Sectors left
+ shl ax,11-4 ; 2048-byte sectors -> segment
+ add [si+6],ax ; Advance buffer pointer
+ and bp,bp
+ jnz .loop
+ mov eax,[si+8] ; Next sector
+ ret
+
+ ; INT 13h with retry
+xint13: mov byte [RetryCount], 6
+.try: pushad
+ int 13h
+ jc .error
+ add sp,byte 8*4 ; Clean up stack
+ ret
+.error: popad
+ dec byte [RetryCount]
+ jnz .try
+
+.real_error: mov si,diskerr_msg
+ call writemsg
+ mov al,ah
+ call writehex2
+ call crlf
+.norge: jmp short .norge
+
+
+rl_checkpt equ $ ; Must be <= 400h
+
+%if (rl_checkpt-$$) > 0x800
+%error "Sector 0 overflow"
+%endif
+
+; ----------------------------------------------------------------------------
+; End of code and data that have to be in the first sector
+; ----------------------------------------------------------------------------
+
+ ;;; ********** THIS STUFF HASN'T BEEN UNIFIED PROPERLY ***********
+
+all_read:
pushad ; Paranoia... in case of return to PXE
pushfd ; ... save as much state as possible
push ds
have_entrypoint:
;
-; Clear Sockets structures
+; Clear Files structures
;
- mov di,Sockets
- mov cx,(MAX_SOCKETS*tftp_port_t_size)/4
+ mov di,Files
+ mov cx,(MAX_OPEN*open_file_t_size)/4
xor eax,eax
rep stosd
;
allocate_socket:
push cx
- mov bx,Sockets
- mov cx,MAX_SOCKETS
+ mov bx,Files
+ mov cx,MAX_OPEN
.check: cmp word [bx], byte 0
je .found
- add bx,tftp_port_t_size
+ add bx,open_file_t_size
loop .check
xor cx,cx ; ZF = 1
pop cx
push ax
mov ax,[NextSocket]
inc ax
- and ax,((1 << (13-MAX_SOCKETS_LG2))-1) | 0xC000
+ and ax,((1 << (13-MAX_OPEN_LG2))-1) | 0xC000
mov [NextSocket],ax
- shl cx,13-MAX_SOCKETS_LG2
+ shl cx,13-MAX_OPEN_LG2
add cx,ax ; ZF = 0
xchg ch,cl ; Convert to network byte order
mov [bx],cx ; Socket in use
projects / profile / ivi / syslinux.git / commitdiff