EMILE/first/first.S
2004-12-07 00:35:33 +00:00

351 lines
7.2 KiB
ArmAsm

/*
*
* (c) 2004 Laurent Vivier <LaurentVivier@wanadoo.fr>
*
*/
.equ sector_size, 512
.equ first_level_size, 2 * sector_size
.ifdef SCSI_SUPPORT
/* SCSI constants */
.equ _SCSIGet, 0x0001
.equ _SCSISelect, 0x0002
.equ _SCSICmd, 0x0003
.equ _SCSIComplete, 0x0004
.equ _SCSIRead, 0x0005
.equ COMPLETION_TIMEOUT, 300
/* SCSI macros */
.macro SCSIDispatch selector
move.w #\selector, -(%sp)
dc.w 0xA815 /* _SCSIDispatch */
move.w (%sp)+, %d0
.endm
.else /* SCSI_SUPPORT */
/* floppy constants */
.equ drive_num, 1
.equ fsFromStart, 1
.equ sectors_per_track, 18
.equ sides, 2
.equ track_size, sector_size * sectors_per_track
.equ track_number, 80
.equ floppy_size, sides * track_size * track_number
.equ second_level_size, floppy_size - first_level_size
/* floppy macros */
.macro PBReadSync
.short 0xA002
.endm
.endif /* SCSI_SUPPORT */
.equ ROMBase, 0x2ae
.macro StripAddress
.short 0xA055
.endm
.macro ReadXPRam
.short 0xA051
.endm
.macro WriteXPRam
.short 0xA052
.endm
.macro NewPtr
.short 0xA11E
.endm
.macro SysError
.short 0xA9C9
.endm
/* Pascal string : length, string */
.macro pString string
pstring_begin_\@:
.byte pstring_end_\@ - pstring_string_\@ - 1
pstring_string_\@:
.string "\string"
pstring_end_\@:
.fill 16 - (pstring_end_\@ - pstring_begin_\@) , 1, 0
.endm
/******************************************************************************
*
* Structure: "Inside Macintosh: Files", p. 2-57
*
*****************************************************************************/
begin:
ID: .short 0x4C4B /* boot blocks signature */
Entry: bra start /* entry point to bootcode */
Version: .short 0x4418 /* boot blocks version number */
PageFlags: .short 0x00 /* used internally */
SysName: pString "Mac Bootloader" /* System filename */
ShellName: pstring "Copyright 2004" /* Finder filename */
Dbg1Name: pString "Laurent Vivier" /* debugger filename */
Dbg2Name: pString "Distributed " /* debugger filename */
ScreenName: pString "under GNU GPL " /* name of startup screen */
HelloName: pString "first level " /* name of startup program */
ScrapName: pString "version 1.2 " /* name of system scrap file */
CntFCBs: .short 10 /* number of FCBs to allocate */
CntEvts: .short 20 /* number of event queue elements */
Heap128K: .long 0x00004300 /* system heap size on 128K Mac */
Heap256K: .long 0x00008000 /* used internally */
SysHeapSize: .long 0x00020000 /* system heap size on all machines */
.ifdef SCSI_SUPPORT
.equ READ_10, 0x28
.equ CDB_offset, 2
.equ CDB_nb_blocks, 7
.align 4
CDB:
.byte READ_10
.byte 0
.long 0 /* offset to read, big-endian, like m68k */
.byte 0
.short 0 /* number of blocks to read, big-endian */
.byte 0
.equ op_inc, 1
.equ op_no_inc, 2
.equ op_stop, 7
.equ TIB_buffer, 2
.equ TIB_size, 6
.align 4
TIB:
.short op_inc
.long 0
.long 0
.short op_stop
.long 0
.long 0
/* SCSI complete result */
stat: .short 0
message: .short 0
.else /* SCSI_SUPPORT */
/******************************************************************************
*
* param block used to load second stage from floppy
*
*****************************************************************************/
param_block:
.long 0 /* qLink : next queue entry */
.short 0 /* qType : queue type */
.short 0 /* ioTrap : routine trap */
.long 0 /* ioCmdAddr: routine address */
.long 0 /* ioCompletion : pointer to completion routine */
.short 0 /* ioResult : result code */
.long 0 /* ioNamePtr : pointer to pathname */
.short drive_num /* ioVRefNum : volume specification */
.short -5 /* ioRefNum: file reference number */
.byte 0 /* ioVersNum : version number */
.byte 0 /* ioPermssn : read/write permission */
.long 0 /* ioMisc : miscellaneaous */
ioBuffer: /* ioBuffer : data buffer */
.long 0
ioReqCount: /* ioReqCount : requested number of bytes */
.long second_level_size
.long 0 /* ioActCount : actual number of bytes */
.short fsFromStart /* ioPosMode : positioning mode and newline char */
ioPosOffset: /* ioPosOffset : positionning offset */
.long first_level_size
.endif /* SCSI_SUPPORT */
/******************************************************************************
*
* start : load the second stage
*
* start is called from the boot block header
*
* call PBReadSync() to read blocks from floppy
* as described in param_block
*
*****************************************************************************/
.align 4
start:
movea.l ROMBase,%a0
move.w 8(%a0), %d1 /* read ROM id */
cmp.w #0x0178, %d1 /* only 24bit ROM */
bls.S bit32_ok
/* test if we are in 32bit mode */
move.l #-1, %d0
StripAddress
cmp.l #-1, %d0
beq.S bit32_ok
/* Switch to 32bit mode */
lea PRAM_buffer(%pc), %a0 /* where to store data */
move.w #1, %d0 /* size of data */
swap %d0
move.w #0x08A, %d0 /* offset in PRAM */
ReadXPRam
lea PRAM_buffer(%pc), %a0
or.b #0x05, (%a0)
move.w #1, %d0 /* size of data */
swap %d0
move.w #0x08A, %d0 /* offset in PRAM */
WriteXPRam
/* jump to reset function in ROM */
movea.l ROMBase,%a0
jmp 0x90(%a0)
bit32_ok:
/* Allocate Memory for second stage loader */
.ifdef SCSI_SUPPORT
/* buffer size to store second level booter */
move.l second_size(%pc), %d0
.else
lea ioReqCount(%pc),%a0
move.l (%a0), %d0
.endif
add.l #4, %d0
NewPtr
move.l %a0, %d0
bne malloc_ok
move.l #1, %d0
SysError
malloc_ok:
add.l #3, %d0
and.l #0xFFFFFFFC.l, %d0
.ifdef SCSI_SUPPORT
lea container_end(%pc), %a6
lea TIB(%pc), %a0 /* TIB */
move.l %d0, TIB_buffer(%a0)
lea PRAM_buffer(%pc), %a0
move.l %d0, (%a0)
scsi_loop:
/* prepare CDB */
lea CDB(%pc), %a0
move.w -(%a6), %d2
beq exit_scsi
move.w %d2, CDB_nb_blocks(%a0)
move.l -(%a6), CDB_offset(%a0)
/* compute # of bytes to transfer = block size * # of blocks */
move.w block_size(%pc), %d1
mulu %d2, %d1
/* prepare TIB */
lea TIB(%pc), %a0 /* TIB */
move.l %d1, TIB_size(%a0)
/* SCSI sequence */
/* SCSIGet */
clr.w -(%sp)
SCSIDispatch(_SCSIGet)
/* SCSISelect */
clr.w -(%sp)
move.w #0, -(%sp)
SCSIDispatch(_SCSISelect)
/* SCSICmd */
clr.w -(%sp)
pea CDB(%pc)
move.w #10, -(%sp)
SCSIDispatch(_SCSICmd)
/* SCSIRead */
clr.w -(%sp)
pea TIB(%pc)
SCSIDispatch(_SCSIRead)
/* SCSIComplete */
clr.w -(%sp)
pea stat(%pc)
pea message(%pc)
move.l #COMPLETION_TIMEOUT, -(%sp)
SCSIDispatch(_SCSIComplete)
bra scsi_loop
exit_scsi:
lea PRAM_buffer(%pc), %a0
move.l (%a0), %a0
.else
/* save result in the ParamBlockRec.ioBuffer */
lea ioBuffer(%pc),%a0
move.l %d0,(%a0)
/* Now, we load the second stage loader */
lea param_block(%pc),%a0
PBReadSync
tst.l %d0
beq read_ok
move.l #2, %d0
SysError
read_ok:
move.l ioBuffer(%pc),%a0
.endif /* SCSI_SUPPORT */
/* call second stage bootloader */
jmp (%a0)
PRAM_buffer:
.long 0
end:
/******************************************************************************
*
* Filler: the boot block is 2 floppy blocks
* as seen on the disk of utilities of MacOS 7.6, we fill with 0xda
*
*****************************************************************************/
.ifdef SCSI_SUPPORT
.fill first_level_size - (end - begin) - 10, 1, 0xda
container_end:
block_size: .short 0
unit_id: .short 0
second_size: .long 0
max_blocks: .short container_end - end
.else
.fill first_level_size - (end - begin), 1, 0xda
.endif