EMILE/first/first.S
2005-05-20 00:24:13 +00:00

374 lines
7.5 KiB
ArmAsm

/*
*
* (c) 2004 Laurent Vivier <LaurentVivier@wanadoo.fr>
*
*/
.chip 68000
.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
.equ SysZone, 0x2a6
.equ TheZone, 0x2a6
.macro SetApplBase
.short 0xa057
.endm
.equ CPUFlag, 0x012F
.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:
moveal SysZone,%a0
addal %pc@(SysHeapSize),%a0
SetApplBase
movel SysZone,TheZone
/* is a 32bit aware ROM ? */
movea.l ROMBase,%a0
move.w 8(%a0), %d1 /* read ROM id */
cmp.w #0x0178, %d1 /* only 24bit ROM */
bls.S bit32_ok
/* is a 32bit aware processor ? */
cmp.w #1, CPUFlags /* Is 68000 or 68010 */
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