i2p/haiku-beta6
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Large cleanup of the bootloader shell code. Replaced the x86 comment.

Browse Source 
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@43182 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
François Revol
2011-11-04 17:22:01 +00:00
parent 55ea3ed849
commit e5081da48c
1 changed files with 68 additions and 155 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/system/boot/platform/atari_m68k/shell.S
+68 -155
View File
@@ -1,29 +1,40 @@
/*
* Copyright 2008-2010, François Revol, revol@free.fr. All rights reserved.
* Copyright 2008-2011, François Revol, revol@free.fr. All rights reserved.
* Copyright 2004-2005, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
* Copyright 2005, Ingo Weinhold, bonefish@users.sf.net.
* Copyright 2007, Haiku, Inc. All Rights Reserved.
* Distributed under the terms of the MIT license.
*/
/** This file contains the boot floppy and BFS boot block entry points for
* the stage 2 boot loader.
* x86 ahead:
* The floppy entry point is at offset 0. It's loaded at 0x07c0:0x000. It
* will load the rest of the loader to 0x1000:0x0200 and execute it.
* The BFS boot block will load the whole stage 2 loader to 0x1000:0x0000
* and will then jump to 0x1000:0x0200 as its entry point.
* This code will then switch to protected mode and will directly call
* the entry function of the embedded ELF part of the loader.
*/
/*
* generate boot floppy:
* cd src/system/boot/platform/atari_m68k/ ; make fixup_tos_floppy_chksum; cd -
* dd if=generated/objects/haiku/m68k/release/system/boot/haiku_loader of=~/floppy.img bs=512 count=20 conv=notrunc
* src/system/boot/platform/atari_m68k/fixup_tos_floppy_chksum ~/floppy.img
* generate .prg:
* generated.m68k/cross-tools/bin/m68k-unknown-haiku-ld -o haiku.prg -T src/system/ldscripts/m68k/boot_prg_atari_m68k.ld generated/objects/haiku/m68k/release/system/boot/boot_loader_atari_m68k
/** This file contains the boot floppy, .PRG and BFS boot block entry points
* for the stage 2 boot loader. All 3 entry points load and relocate the
* loader so that it ends up being at ATARI_ZBEOS_BASE.
* This file is built as PIC so it works wherever it is executed.
* Some arithmetic is thus needed to set variables in the relocated code.
* The loader .PRG file is created from the bootloader by a custom ldscript.
*
* Known load addresses:
* floppy: 0x00a34c (EmuTOS in ARAnyM)
* .prg: 0x03543e (depends on the TOS memory)
* BFS: is set in the MBR code.
*
* The floppy and .PRG code is entered at _bs_entry, which jumps further on
* to skip some fake FAT descriptor.
* It first determines which way it was loaded (floppy boot happens in
* supervisor mode, while .PRG are loaded as user code), and jumps to
* the specific part.
*
* The floppy code comes first as it must be in the first sector,
* and loads the rest of the loader at ATARI_ZBEOS_BASE+0x200,
* sets up the new stack and jumps to _start after setting some variables.
* The end of the floppy code contains a placeholder for a checksum which
* is calculated at build-time by the <build>fixup_tos_floppy_chksum tool.
*
* The .PRG code switches to supervisor mode, copies the whole loader
* which is already in memory to ATARI_ZBEOS_BASE. It then sets up the new
* stack and some variables and jumps to _start.
*
* The BFS code is yet to be fully written.
*/
/*
@@ -76,11 +87,10 @@ _fat_spt:
// we're done
sNumSectors:
// this location will contain the length of the boot loader as
// written by the "makeflop" command in 512 byte blocks
// 0x180 is the allowed maximum, as the zipped TAR with the
// kernel and the boot module might start at offset 192 kB
//.word 0x0300 //0x0180
// This location will contain the max length of the boot loader
// as written by the build system in 512 byte blocks and depends
// on the offset of the zipped TAR with the kernel and the boot
// modules will start at offset BOOT_ARCHIVE_IMAGE_OFFSET kB.
.word BOOT_ARCHIVE_IMAGE_OFFSET*2
real_entry:
@@ -89,11 +99,16 @@ real_entry:
// http://ftp.netbsd.org/pub/NetBSD/NetBSD-release-3-0/src/sys/arch/atari/stand/xxboot/fdboot/fdboot.S
movem.l %d1-%d7/%a0-%a6,-(%sp)
//DEBUG: determine load location
// lea _bs_entry(%pc),%a0
// move.l %a0,%d0
// bsr putx
lea str,%a0
bsr puts
// first, determine if .prg (user) or bootsect (super)
// Super()
// Super(SUP_INQUIRE)
move.l #SUP_INQUIRE,-(%sp)
move.w #0x20,-(%sp)
trap #GEMDOS_TRAP
@@ -108,46 +123,39 @@ real_entry:
*/
floppy_start:
lea label_floppy,%a0
bsr puts
//bra floppy_start
//lea label_floppy,%a0
//bsr puts
// no interrupt
//or.w #0x0700,%sr
//XXX: check for enough RAM
// load the rest
//move.w sNumSectors,%d2
// load at base + this code.
//move.l #(ATARI_ZBEOS_BASE+512),%a2
//move.l %a2,%d0
//bsr putx
bsr load_sectors
tst.w %d0
bne load_failed
floppy_done:
// setup stack
move.l #ATARI_ZBEOS_STACK_END,%sp
//jmp ATARI_ZBEOS_BASE+512
floppy_done:
move.b #ATARI_BOOT_DRVAPI_FLOPPY,ATARI_ZBEOS_BASE + gBootDriveAPI - _bs_entry
move.w TOSVAR_bootdev,%d0
// XXX: use uint16 ??
move.b %d0,ATARI_ZBEOS_BASE + gBootDriveID - _bs_entry
move.b #1,ATARI_ZBEOS_BASE + gBootedFromImage - _bs_entry
all_done:
// setup stack
move.l #ATARI_ZBEOS_STACK_END,%sp
// say goodbye to TOS
lea msg_j1,%a0
bsr puts
move.l #0,%d0
//bra spin
// say hello to haiku_loader
jmp _start
load_failed:
//bra _exit
spin:
//bra spin
bra spin
_exit: /* */
lea failure_string,%a0
bsr puts
@@ -163,43 +171,6 @@ _exit: /* */
load_sectors:
#if 0
/* it seems to skip 9 every 9 sectors, buggy side handling ? */
// Rwabs
//move.l #1,-(%sp)
move.w #0,-(%sp) // A:
//move.w #2,-(%sp) // C:
//move.w #-1,-(%sp) // 2nd sector
move.w #1,-(%sp) // 2nd sector
move.w %d2,-(%sp)
move.l %a2,-(%sp)
//move.w #RW_READ+RW_NOTRANSLATE,-(%sp)
move.w #RW_READ+RW_NOMEDIACH,-(%sp)
move.w #4,-(%sp)
trap #13
add.l #14,%sp
#endif
#if 0
// d2:
//move.w %d2,-(%sp)
move.w #1,-(%sp) // count
move.w #0,-(%sp) // sideno
move.w #0,-(%sp) // trackno
move.w #1,-(%sp) // sectno
move.w TOSVAR_bootdev,-(%sp) // devno
clr.l -(%sp) // filler
//move.w #0,-(%sp)
//move.l %a2,-(%sp)
move.l #ATARI_ZBEOS_BASE,-(%sp)
move.w #8,-(%sp) // floprd
trap #XBIOS_TRAP
add.l #20,%sp
#endif
//bsr putx
//rts
/*
* %d3: remaining sects
* %d4: sectno
@@ -233,19 +204,6 @@ read_sectors_loop:
// compute next track/side/sector
read_sectors_next:
#if 0 //DEBUG
// [TRAK][SIDE]
move.w %d5,%d0
swap %d0
move.w %d6,%d0
bsr putx
// [SECT][S/TK]
move.w %d4,%d0
swap %d0
move.w %d7,%d0
bsr putx
//bsr getc
#endif //!DEBUG
add.l #SECTSIZE,%a5
addq.w #1,%d4 // sectno++
cmp.w %d7,%d4 // if (sectno == spt)
@@ -286,12 +244,7 @@ read_sect: /* read 1 sector */
* %a5: buffer
*
*/
#if 1
//move.w %d2,-(%sp)
//move.w #1,-(%sp) // count
//move.w #0,-(%sp) // sideno
//move.w #0,-(%sp) // trackno
//move.w #2,-(%sp) // sectno
move.w #1,-(%sp)
movem.w %d4-%d6,-(%sp)
move.w TOSVAR_bootdev,-(%sp) // devno
@@ -301,8 +254,6 @@ read_sect: /* read 1 sector */
trap #XBIOS_TRAP
add.l #20,%sp
tst.l %d0
#endif
rts
floppy_end:
@@ -312,10 +263,6 @@ failure_string:
.string " Loading failed! Press key.\r\n"
// .string "FAIL"
// .org DOT_STRING
// .string "."
putx:
@@ -325,15 +272,11 @@ putx:
putxloop:
move.l %d1,%d0
lsl.l #4,%d1
//swap %d0
//lsr.l #8,%d0
//lsr.l #4,%d0
rol.l #4,%d0
and.l #0x0f,%d0
cmp.b #9,%d0
ble putx0
add.b #'a'-'0'-10,%d0
//bra putxdisp
putx0:
add.b #'0',%d0
putxdisp:
@@ -382,35 +325,36 @@ getc:
str:
.string "Haiku!"
label_prg:
.string "P" //"RG boot"
label_floppy:
.string "F" //"loppy boot"
h4:
.string "H4"
h5:
.string "H5"
//label_prg:
// .string "P" //"RG boot"
//label_floppy:
// .string "F" //"loppy boot"
msg_j1:
.string "Jumping to haiku_loader."
shell_end:
//.fill (0x01fe - shell_end), 1, 0x55
.org 0x01fe
boot_code_checksum:
.word 0xaa55-1 // will be replaced by the one calculated by the build.
// we make sure PCs don't try to execute it.
// this bumps the "start" label to offset 0x0200 as
// expected by the BFS boot loader, and also marks
// this block as valid boot block for the BIOS
//XXX: put bfs_start here
bfs_start:
//FIXME:write BFS code
/*
* \AUTO\HAIKU.PRG and ARAnyM BOOTSTRAP() support code
*/
prg_start:
lea label_prg,%a0
bsr puts
//lea label_prg,%a0
//bsr puts
// .prg:
// we need to switch to supervisor mode anyway
@@ -420,34 +364,9 @@ prg_start:
addq.l #6,%sp
move.l %d0,saved_super_stack
#if 0
//_membot
move.l #0x432,%a0
move.l (%a0),%d0
bsr putx
//_memtop
move.l #0x436,%a0
move.l (%a0),%d0
bsr putx
//_v_bas_ad
move.l #0x44e,%a0
move.l (%a0),%d0
bsr putx
#endif
// disable interrupts
//or.w #0x0700,%sr
// setup stack
move.l #ATARI_ZBEOS_STACK_END,%sp
lea h5,%a0
bsr puts
lea _bs_entry,%a0
move.l %a0,%d0
bsr putx
// copy the rest of the prg
// load counter
@@ -467,22 +386,16 @@ copysect_loop:
//bsr putx
dbf %d0,nextsect
lea msg_j1,%a0
bsr puts
// all done
super_done:
// XXX: copy the rest !
#if 1
// XXX: force floppy boot for testing to get the kernel tgz for now
move.b #ATARI_BOOT_DRVAPI_FLOPPY,ATARI_ZBEOS_BASE + gBootDriveAPI - _bs_entry
move.b #0,ATARI_ZBEOS_BASE + gBootDriveID - _bs_entry
move.b #1,ATARI_ZBEOS_BASE + gBootedFromImage - _bs_entry
#endif
move.l #0,%d0
//jmp ATARI_ZBEOS_BASE+512
jmp _start
// all done, go to _start
bra all_done
saved_super_stack:
.long 0