rev |
line source |
pascal@18140
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1 BOOTSEG = 0x07C0 /* original address of boot-sector */
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pascal@18140
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2 SYSSEG = 0x1000 /* historical load address >> 4 */
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pascal@18140
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3 INITSEG = 0x9000 /* boot address >> 4 */
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pascal@18140
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4 SETUPSEG = 0x9020 /* setup address >> 4 */
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pascal@18140
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5 ASK_VGA = -3
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pascal@18140
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6
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pascal@18140
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7 #ifndef SVGA_MODE
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pascal@18140
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8 #define SVGA_MODE ASK_VGA
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pascal@18140
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9 #endif
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pascal@18140
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10
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pascal@18140
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11 #ifndef RAMDISK
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pascal@18140
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12 #define RAMDISK 0
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pascal@18140
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13 #endif
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pascal@18140
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14
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pascal@18140
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15 #ifndef ROOT_RDONLY
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pascal@18140
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16 #define ROOT_RDONLY 1
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pascal@18140
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17 #endif
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pascal@18140
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18
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pascal@18140
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19 /* some extra features */
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pascal@18140
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20 #define CMDLINE kernel >= 2.4
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pascal@18140
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21 #define OLDCMDLINE kernel < 2.4
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pascal@18140
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22 #define HELP display version for ? argument
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pascal@18140
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23 #define MORETHAN16M up to 4Gb RAM, not 16Mb
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pascal@18140
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24 #define KEYBOARDLESS_SUPPORT scan floppy swap each 5 seconds
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pascal@18140
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25
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pascal@18140
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26 #define EDIT_CMDLINE
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pascal@18140
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27 #define CMDLINE_SUPPORT
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pascal@18140
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28 #define MOVE_CMDLINE
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pascal@18140
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29 #define INITRD_SUPPORT
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pascal@18140
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30 #define INITRD_AUTOADDR
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pascal@18140
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31 #define MULTI_INITRD many in one support
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pascal@18140
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32
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pascal@18140
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33 .code16
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pascal@18140
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34 .org 0
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pascal@18140
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35
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pascal@18140
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36 bootsect_start:
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pascal@18140
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37
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pascal@18140
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38 cur_initrd_size_ofs = 494
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pascal@18140
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39 ramdisk_image_ofs = 0x218
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pascal@18140
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40 ramdisk_image = bootsect_start+ramdisk_image_ofs
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pascal@18140
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41 ramdisk_size_ofs = 0x21C
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pascal@18140
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42 ramdisk_size = bootsect_start+ramdisk_size_ofs
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pascal@18140
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43 cmd_line_ptr_ofs = 0x228
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pascal@18140
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44 cmd_line_ptr = bootsect_start+cmd_line_ptr_ofs
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pascal@18140
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45 setup_sects = bootsect_start+497
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pascal@18140
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46 syssize = bootsect_start+500
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pascal@18140
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47 boot_flag_ofs = 510
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pascal@18140
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48 boot_flag = bootsect_start+boot_flag_ofs
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pascal@18140
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49
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pascal@18140
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50
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pascal@18140
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51 stacktop = 0x9E00 # in 0x8000 .. 0xA000
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pascal@18140
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52 zeroed = 48+10 # gdt + zeroed registers
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pascal@18140
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53 .macro INIT_REGS
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pascal@18140
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54 movw $stacktop-zeroed, %di # stacktop is an arbitrary value >=
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pascal@18140
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55 # length of bootsect + length of
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pascal@18140
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56 # setup + room for stack;
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pascal@18140
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57 # 12 is disk parm size.
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pascal@18140
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58 pushw $INITSEG
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pascal@18140
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59 popw %ss # %ss contain INITSEG
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pascal@18140
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60 movw %di, %sp # put stack at INITSEG:stacktop-...
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pascal@18140
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61 pushw %ss
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pascal@18140
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62 popw %es # %es = %ss = INITSEG
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pascal@18140
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63 xorw %ax, %ax # %ax = 0
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pascal@18140
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64 #if defined(CMDLINE)
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pascal@18140
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65 movw $zeroed+1, %cx # clear gdt + offset, %ds, limits, cmdline=""
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pascal@18140
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66 rep # don't worry about cld
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pascal@18140
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67 stosb # already done above
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pascal@18140
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68 decw %di
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pascal@18140
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69 #else
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pascal@18140
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70 movw $zeroed/2, %cx # clear gdt + offset, %ds, limits
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pascal@18140
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71 rep # don't worry about cld
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pascal@18140
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72 stosw # already done above
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pascal@18140
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73 #endif
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pascal@18140
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74 popw %bx # offset = 0
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pascal@18140
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75 .endm
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pascal@18140
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76
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pascal@18140
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77 LOADSEG = 0x8000 # 0x1000 multiple, up to 512K zImage
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pascal@18140
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78 LOADSZ = 0x10000
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pascal@18140
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79
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pascal@18140
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80 # bootsect_start:
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pascal@18140
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81 INIT_REGS
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pascal@18140
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82 popw %ds # %ds = 0
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pascal@18140
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83 movb setup_sects+0x7C00, %al # read bootsector + setup
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pascal@18140
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84 incw %ax # %ax = setup_sects+bootsect
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pascal@18140
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85 popw %fs # %fs = 0
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pascal@18140
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86
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pascal@18140
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87 # Many BIOS's default disk parameter tables will not recognize
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pascal@18140
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88 # multi-sector reads beyond the maximum sector number specified
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pascal@18140
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89 # in the default diskette parameter tables - this may mean 7
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pascal@18140
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90 # sectors in some cases.
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pascal@18140
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91 #
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pascal@18140
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92 # Since single sector reads are slow and out of the question,
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pascal@18140
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93 # we must take care of this by creating new parameter tables
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pascal@18140
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94 # (for the first disk) in RAM. We can set the maximum sector
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pascal@18140
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95 # count to 36 - the most we will encounter on an ED 2.88.
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pascal@18140
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96 #
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pascal@18140
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97 # High doesn't hurt. Low does. Let's use the max: 63
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pascal@18140
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98
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pascal@18140
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99 ldsw 0x78(%bx), %si # %ds:%bx+0x78 is parameter table address
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pascal@18140
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100 popw %di
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pascal@18140
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101 pushw %es
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pascal@18140
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102 pushw %di
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pascal@18140
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103 #ifdef CMDLINE_SUPPORT
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pascal@18140
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104 movw $0, %bp # patched by installer (7C22)
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pascal@18140
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105 skipcmdline:
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pascal@18140
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106 #define cmd_line_ptr 0x22
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pascal@18140
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107 #endif
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pascal@18140
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108 movb $6, %cl # copy 12 bytes
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pascal@18140
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109 rep # don't worry about cld
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pascal@18140
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110 movsw # already done above
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pascal@18140
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111 pushw %ss
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pascal@18140
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112 popw %ds # now %ds = %es = %ss = INITSEG
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pascal@18140
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113 popl %fs:0x78(%bx) # update parameter table address
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pascal@18140
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114 movb $63, 0x4-12(%di) # patch sector count, %di = stacktop
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pascal@18140
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115 cli
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pascal@18140
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116
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pascal@18140
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117 xchg %ax, %di # sector count
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pascal@18140
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118 popw %ax # limits = 0
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pascal@18140
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119 incw %cx # cylinder 0, sector 1, clear Z
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pascal@18140
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120 call read_first_sectors # read setup
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pascal@18140
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121 loadsys:
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pascal@18140
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122 movw $0x200,%si
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pascal@18140
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123 type_of_loader = 0x10
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pascal@18140
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124 loadflags = 0x11
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pascal@18140
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125 heap_end_ptr = 0x24
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pascal@18140
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126 orw $0x8020, type_of_loader(%si) # loader type = 0x20 = bootsect-loader
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pascal@18140
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127 movb $(stacktop-0x300)/256, heap_end_ptr+1(%si)
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pascal@18140
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128 call puts_version # show which kernel we are loading
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pascal@18140
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129
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pascal@18140
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130 #ifdef CMDLINE_SUPPORT
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pascal@18140
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131 # The cmdline can be entered and modifed at boot time.
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pascal@18140
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132 # Only characters before the cursor are passed to the kernel.
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pascal@18140
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133
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pascal@18140
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134 xorw %si, %si
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pascal@18140
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135 orw cmd_line_ptr-7(%bx), %si
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pascal@18140
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136 jz nocmdline
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pascal@18140
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137 #ifdef OLDCMDLINE
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pascal@18140
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138 movw $0xA33F, cmd_line_ptr-2-7(%bx)
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pascal@18140
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139 #endif
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pascal@18140
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140 call puts
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pascal@18140
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141 #if defined(MOVE_CMDLINE) || (defined(EDIT_CMDLINE) && defined(KEYBOARDLESS_SUPPORT))
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pascal@18140
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142 pushw %di
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pascal@18140
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143 #endif
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pascal@18140
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144 #ifdef EDIT_CMDLINE
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pascal@18140
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145 cmdlp:
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pascal@18140
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146 movb $0x20, %al # clear end of line
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pascal@18140
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147 cmdlpz:
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pascal@18140
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148 call putc # with Space
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pascal@18140
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149 subb $0x18, %al # and BackSpace
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pascal@18140
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150 jnc cmdlpz
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pascal@18140
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151 decw %si
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pascal@18140
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152 cmdget:
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pascal@18140
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153 #ifdef KEYBOARDLESS_SUPPORT
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pascal@18140
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154 call wait4key
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pascal@18140
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155 #else
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pascal@18140
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156 int $0x16
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pascal@18140
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157 #endif
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pascal@18140
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158 cbw # %ah = 0, get keyboard character
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pascal@18140
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159 cmpb $8, %al # BackSpace ?
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pascal@18140
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160 je cmdbs
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pascal@18140
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161 movb %al, (%si) # store char
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pascal@18140
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162 lodsw # %si += 2
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pascal@18140
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163 cmdbs:
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pascal@18140
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164 cmpw %si, cmd_line_ptr-7(%bx)
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pascal@18140
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165 je cmdget
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pascal@18140
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166 call putc
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pascal@18140
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167 cmpb $10, %al # Enter/linefeed ?
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pascal@18140
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168 jne cmdlp
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pascal@18140
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169 movb %bh,-2(%si) # set end of string and remove CR
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pascal@18140
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170 endcmdline:
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pascal@18140
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171 #endif
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pascal@18140
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172 #ifdef MOVE_CMDLINE
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pascal@18140
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173 pushw %ss
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pascal@18140
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174 popw %es
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pascal@18140
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175 movw $0x8000, %di
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pascal@18140
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176 movw %di, %si
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pascal@18140
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177 xchgw %si, cmd_line_ptr-7(%bx)
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pascal@18140
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178 movb $0x2, %ch
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pascal@18140
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179 rep
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pascal@18140
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180 movsb
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pascal@18140
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181 #endif
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pascal@18140
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182 #if defined(EDIT_CMDLINE) || (defined(MOVE_CMDLINE) && defined(KEYBOARD_TIMEOUT))
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pascal@18140
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183 popw %di
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pascal@18140
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184 #endif
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pascal@18140
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185 nocmdline:
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pascal@18140
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186 #endif
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pascal@18140
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187
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pascal@18140
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188 # This routine loads the system at address LOADSEG, making sure
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pascal@18140
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189 # no 64kB boundaries are crossed. We try to load it as fast as
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pascal@18140
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190 # possible, loading whole tracks whenever we can.
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pascal@18140
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191
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pascal@18140
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192 .macro autoaddr base
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pascal@18140
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193 #ifdef INITRD_AUTOADDR
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pascal@18140
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194 movb $0x88, %ah
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pascal@18140
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195 int $0x15
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pascal@18140
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196 //jc NeedMoreRAM # error code 80 or 86
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pascal@18140
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197 cmpw $0xC000, %ax # more than 49M ?
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pascal@18140
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198 jb NeedMoreRAM
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pascal@18140
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199 movb %ch, bootsect_dst_base_hi(%si) # initramfs @ 32M
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pascal@18140
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200 movb %ch, ramdisk_image_ofs+3-\base
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pascal@18140
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201 NeedMoreRAM:
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pascal@18140
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202 #endif
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pascal@18140
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203 .endm
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pascal@18140
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204
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pascal@18140
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205 bootsect_src_limit = 16
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pascal@18140
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206 bootsect_dst_limit = 24
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pascal@18140
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207 bootsect_src_base = 18
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pascal@18140
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208 bootsect_dst_base = 26 # bits 0..23
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pascal@18140
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209 bootsect_dst_base_hi = 31 # bits 24..31
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pascal@18140
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210 popw %bx # clear %bx
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pascal@18140
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211 movw %sp, %si # for bootsect_gdt
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pascal@18140
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212 init_gdt:
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pascal@18140
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213 decw bootsect_src_limit(%bx,%si) # max 64Kb
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pascal@18140
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214 movw $0x9300+(LOADSEG/0x1000), bootsect_src_base+2(%bx,%si)
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pascal@18140
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215 xorb $bootsect_dst_limit-bootsect_src_limit, %bl
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pascal@18140
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216 jne init_gdt
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pascal@18140
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217 #ifdef INITRD_SUPPORT
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pascal@18140
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218 movw $syssize, %bx
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pascal@18140
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219 movb $5, %cl
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pascal@18140
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220 code32_start = 0x214
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pascal@18140
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221 movw code32_start+1, %ax # destination = 0x00100000 or 0x00010000
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pascal@18140
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222 initrdlp:
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pascal@18140
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223 movl (%bx), %ebx
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pascal@18140
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224 decl %ebx
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pascal@18140
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225 shrl %cl, %ebx
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pascal@18140
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226 #else
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pascal@18140
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227 code32_start = 0x214
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pascal@18140
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228 movw code32_start+1, %ax # destination = 0x00100000 or 0x00010000
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pascal@18140
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229 movl syssize, %ebx
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pascal@18140
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230 decl %ebx
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pascal@18140
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231 shrl $5, %ebx
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pascal@18140
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232 #endif
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pascal@18140
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233 #ifdef MORETHAN16M
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pascal@18140
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234 incl %ebx
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pascal@18140
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235 #else
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pascal@18140
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236 incw %bx
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pascal@18140
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237 #endif
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pascal@18140
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238 syslp:
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pascal@18140
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239 movw %ax, bootsect_dst_base+1(%si)
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pascal@18140
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240 #ifdef MORETHAN16M
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pascal@18140
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241 movl $LOADSZ/512, %edi # size in sectors
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pascal@18140
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242 subl %edi, %ebx
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pascal@18140
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243 #else
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pascal@18140
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244 movw $LOADSZ/512, %di # size in sectors
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pascal@18140
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245 subw %di, %bx
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pascal@18140
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246 #endif
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pascal@18140
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247 pushf
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pascal@18140
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248 jnc not_last
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pascal@18140
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249 addw %bx, %di
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pascal@18140
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250 not_last:
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pascal@18140
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251 #ifdef MULTI_INITRD
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pascal@18140
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252 pushw %di
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pascal@18140
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253 #endif
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pascal@18140
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254 pushw %ax
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pascal@18140
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255 pushw %bx
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pascal@18140
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256 pushw %si
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pascal@18140
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257 xorw %bx,%bx
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pascal@18140
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258 pushw $LOADSEG
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pascal@18140
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259 popw %es
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pascal@18140
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260 patchcall:
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pascal@18140
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261 call read_sectors # update %bp
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pascal@18140
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262 popw %si
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pascal@18140
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263 popw %bx
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pascal@18140
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264 movw %es, %cx # word count = LOADSZ/2 (= LOADSEG)
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pascal@18140
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265 movb $0x87, %ah
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pascal@18140
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266 pushw %ss
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pascal@18140
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267 popw %es # restore es
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pascal@18140
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268 int $0x15 # max 16M, maybe more...
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pascal@18140
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269 popw %ax
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pascal@18140
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270 #ifdef MULTI_INITRD
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pascal@18140
|
271 popw %di
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pascal@18140
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272 shlw $1,%di # sectors to pages
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pascal@18140
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273 addw %di, %ax
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pascal@18140
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274 #ifdef MORETHAN16M
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pascal@18140
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275 adcb %cl, bootsect_dst_base_hi(%si) # breaks 16M limit ?
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pascal@18140
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276 #endif
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pascal@18140
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277 #else
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pascal@18140
|
278 #ifdef MORETHAN16M
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pascal@18140
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279 addw $0x100, %ax # next dest (ax+=LOADSZ/256)
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pascal@18140
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280 adcb %cl, bootsect_dst_base_hi(%si) # breaks 16M limit ?
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pascal@18140
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281 #else
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pascal@18140
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282 incb %ah # next dest (ax+=LOADSZ/256)
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pascal@18140
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283 #endif
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pascal@18140
|
284 #endif
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pascal@18140
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285 popf
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pascal@18140
|
286 ja syslp
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pascal@18140
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287 #ifdef INITRD_SUPPORT
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pascal@18140
|
288 initrdlp2:
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pascal@18140
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289 #ifdef INITRD_AUTOADDR
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pascal@18140
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290 movw $0x209, %cx
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pascal@18140
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291 #else
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pascal@18140
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292 movb $9, %cl
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pascal@18140
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293 #endif
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pascal@18140
|
294 #ifdef MULTI_INITRD
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pascal@18140
|
295 movw $cur_initrd_size_ofs, %di
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pascal@18140
|
296 movw (%di), %bx
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pascal@18140
|
297 addw $4, (%di)
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pascal@18140
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298 shrw %cl, boot_flag_ofs-cur_initrd_size_ofs(%di)
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pascal@18140
|
299 je nextInitrd
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pascal@18140
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300 orw %bx, %bx
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pascal@18140
|
301 je bootit # no initrd
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pascal@18140
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302 autoaddr cur_initrd_size_ofs(%di)
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pascal@18140
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303 movw ramdisk_image+1,%ax
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pascal@18140
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304 jmp initrdlp
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pascal@18140
|
305 nextInitrd:
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pascal@18140
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306 pushw %bx
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pascal@18140
|
307 movl -4(%bx), %ebx
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pascal@18140
|
308 addl %ebx, ramdisk_size_ofs-cur_initrd_size_ofs(%di)
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pascal@18140
|
309 popw %bx
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pascal@18140
|
310 cmpb 2(%di), %bl
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pascal@18140
|
311 jb initrdlp
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pascal@18140
|
312 #else
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pascal@18140
|
313 movw $ramdisk_size, %bx
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pascal@18140
|
314 autoaddr ramdisk_size_ofs(%bx)
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pascal@18140
|
315 movw ramdisk_image+1,%ax
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pascal@18140
|
316 #ifdef MORETHAN16M
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pascal@18140
|
317 cmpb %cl, ramdisk_image+2-ramdisk_size(%bx)
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pascal@18140
|
318 jb bootit
|
pascal@18140
|
319 shrw %cl, boot_flag-ramdisk_size(%bx)
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pascal@18140
|
320 jne initrdlp
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pascal@18140
|
321 #else
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pascal@18140
|
322 cmpw %ax, bootsect_dst_base+1(%si)
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pascal@18140
|
323 jb initrdlp
|
pascal@18140
|
324 #endif
|
pascal@18140
|
325 #endif
|
pascal@18140
|
326 #endif
|
pascal@18140
|
327 #ifdef MULTI_INITRD
|
pascal@18140
|
328 bootit:
|
pascal@18140
|
329 jcxz read_sectorslp
|
pascal@18140
|
330 #endif
|
pascal@18140
|
331
|
pascal@18140
|
332 # This procedure turns off the floppy drive motor, so
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pascal@18140
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333 # that we enter the kernel in a known state, and
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pascal@18140
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334 # don't have to worry about it later.
|
pascal@18140
|
335
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pascal@18140
|
336 kill_motor:
|
pascal@18140
|
337 xchgw %ax, %di # reset FDC (%di < 128)
|
pascal@18140
|
338 int $0x13
|
pascal@18140
|
339
|
pascal@18140
|
340 # After that (everything loaded), we jump to the setup-routine
|
pascal@18140
|
341 # loaded directly after the bootblock:
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pascal@18140
|
342 # Segments are as follows: %ds = %ss = INITSEG
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pascal@18140
|
343
|
pascal@18140
|
344 ljmp $SETUPSEG, $0
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pascal@18140
|
345
|
pascal@18140
|
346 # read_sectors reads %di sectors into %es:0 buffer.
|
pascal@18140
|
347 # %es:0 is updated to the next memory location.
|
pascal@18140
|
348 # First, sectors are read sector by sector until
|
pascal@18140
|
349 # sector per track count is known. Then they are
|
pascal@18140
|
350 # read track by track.
|
pascal@18140
|
351 # Assume no error on first track.
|
pascal@18140
|
352
|
pascal@18140
|
353 #define FLOPPY_CYLINDERS 80
|
pascal@18140
|
354 #define FLOPPY_HEADS 2
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pascal@18140
|
355
|
pascal@18140
|
356 check_limits:
|
pascal@18140
|
357 popw %dx
|
pascal@18140
|
358 cmpb %al, %cl # max sector known ?
|
pascal@18140
|
359 ja next_head # no -> store it
|
pascal@18140
|
360 pushaw
|
pascal@18140
|
361 int $0x13 # reset controler
|
pascal@18140
|
362 stc
|
pascal@18140
|
363 call putcdot # print '-'
|
pascal@18140
|
364 read_sectorslp:
|
pascal@18140
|
365 popaw
|
pascal@18140
|
366 bdendlp:
|
pascal@18140
|
367 pushw %dx # some bios break dx...
|
pascal@18140
|
368 pushw %ax # limits
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pascal@18140
|
369 subb %cl, %al # sectors remaining in track
|
pascal@18140
|
370 ja tolastsect
|
pascal@18140
|
371 movb $1, %al # 1 sector mini
|
pascal@18140
|
372 tolastsect:
|
pascal@18140
|
373 cmpw %di, %ax
|
pascal@18140
|
374 jb more1trk
|
pascal@18140
|
375 movw %di, %ax # sectors to read
|
pascal@18140
|
376 more1trk:
|
pascal@18140
|
377 pushw %ax # save context
|
pascal@18140
|
378 movb $2, %ah # cmd: read chs
|
pascal@18140
|
379 int $0x13
|
pascal@18140
|
380 popw %dx # save %ax
|
pascal@18140
|
381 popw %ax # limits
|
pascal@18140
|
382 jc check_limits
|
pascal@18140
|
383 xchgw %ax, %bp
|
pascal@18140
|
384 addw %dx,%cx # next sector
|
pascal@18140
|
385 movw %cx, %gs
|
pascal@18140
|
386 addb %dl,%bh
|
pascal@18140
|
387 addb %dl,%bh # next location
|
pascal@18140
|
388 subw %dx,%di # update sector counter
|
pascal@18140
|
389 popw %dx
|
pascal@18140
|
390 jz putcdot
|
pascal@18140
|
391 read_sectors:
|
pascal@18140
|
392 movw %gs, %cx
|
pascal@18140
|
393 # al is last sector+1
|
pascal@18140
|
394 # ah is 0
|
pascal@18140
|
395 xchgw %ax, %bp
|
pascal@18140
|
396 cmpb %al,%cl # reach sector limit ?
|
pascal@18140
|
397 jne bdendlp
|
pascal@18140
|
398 next_head:
|
pascal@18140
|
399 movb %cl,%al
|
pascal@18140
|
400 movb $1, %cl # first sector
|
pascal@18140
|
401 inc_head:
|
pascal@18140
|
402 xorb %cl, %dh # next head
|
pascal@18140
|
403 jne bdendlp # reach head limit ?
|
pascal@18140
|
404 incb %ch # next cylinder
|
pascal@18140
|
405 read_first_sectors:
|
pascal@18140
|
406 cmpb $FLOPPY_CYLINDERS,%ch # reach cylinder limit ?
|
pascal@18140
|
407 jne bdendlp
|
pascal@18140
|
408 next_floppy:
|
pascal@18140
|
409 movb $0,%ch # first cylinder
|
pascal@18140
|
410 pushaw
|
pascal@18140
|
411 movw $swap_floppy,%si
|
pascal@18140
|
412 #ifdef KEYBOARDLESS_SUPPORT
|
pascal@18140
|
413 pushw %bx
|
pascal@18140
|
414 call puts
|
pascal@18140
|
415 popw %bx
|
pascal@18140
|
416 movw %si, %bp
|
pascal@18140
|
417 waitfloppy:
|
pascal@18140
|
418 call wait
|
pascal@18140
|
419 jne waitfloppydone
|
pascal@18140
|
420 #ifdef MULTI_INITRD
|
pascal@18140
|
421 decb (%si) # max_timeouts
|
pascal@18140
|
422 jz gobootit
|
pascal@18140
|
423 #endif
|
pascal@18140
|
424 pushw %dx # some bios break dx...
|
pascal@18140
|
425 cbw
|
pascal@18140
|
426 int $0x13 # reset FDC
|
pascal@18140
|
427 movw $0x201,%ax
|
pascal@18140
|
428 int $0x13 # read first sector
|
pascal@18140
|
429 popw %dx
|
pascal@18140
|
430 rclb $1,%ah # floppy changed 06=>0D no error 00
|
pascal@18140
|
431 cmpb -2(%bp), %ah # 0D then 00
|
pascal@18140
|
432 jne waitfloppy # no => try again
|
pascal@18140
|
433 incw %bp
|
pascal@18140
|
434 decw %ax # was 0001 ?
|
pascal@18140
|
435 jne waitfloppy
|
pascal@18140
|
436 waitfloppydone:
|
pascal@18140
|
437 #else
|
pascal@18140
|
438 call puts
|
pascal@18140
|
439 cbw # %ah = 0, get keyboard character
|
pascal@18140
|
440 int $0x16
|
pascal@18140
|
441 #endif
|
pascal@18140
|
442 #ifdef MULTI_INITRD
|
pascal@18140
|
443 orb $0x20, %al
|
pascal@18140
|
444 cmp $'b', %al
|
pascal@18140
|
445 jnz read_sectorslp
|
pascal@18140
|
446 gobootit:
|
pascal@18140
|
447 //movw ramdisk_size+2-max_timeouts(%si), %cx
|
pascal@18140
|
448 .byte 0x8B, 0x4C, ramdisk_size+2-max_timeouts
|
pascal@18140
|
449 jmp bootit
|
pascal@18140
|
450 #else
|
pascal@18140
|
451 jmp read_sectorslp
|
pascal@18140
|
452 #endif
|
pascal@18140
|
453
|
pascal@18140
|
454 putcdot:
|
pascal@18140
|
455 movb $'.'+3, %al // . = success, - = failure
|
pascal@18140
|
456 putclf:
|
pascal@18140
|
457 sbbb $3, %al
|
pascal@18140
|
458 putc:
|
pascal@18140
|
459 movb $0xe, %ah
|
pascal@18140
|
460 movw $7, %bx # one dot each 64k
|
pascal@18140
|
461 int $0x10
|
pascal@18140
|
462 cmp $0xd, %al # CR ?
|
pascal@18140
|
463 je putclf
|
pascal@18140
|
464 ret
|
pascal@18140
|
465
|
pascal@18140
|
466 #ifdef KEYBOARDLESS_SUPPORT
|
pascal@18140
|
467 clock = 0x46C
|
pascal@18140
|
468 wait:
|
pascal@18140
|
469 wait4key:
|
pascal@18140
|
470 movw $clock, %di
|
pascal@18140
|
471 #define DELAY 5
|
pascal@18140
|
472 movb $257-(DELAY*182)/10, %fs:(%di)
|
pascal@18140
|
473 waitkbd:
|
pascal@18140
|
474 movw $0x10D, %ax # test keyboard, timeout => CR
|
pascal@18140
|
475 cmpb %fs:(%di),%ah
|
pascal@18140
|
476 je waitdone
|
pascal@18140
|
477 int $0x16
|
pascal@18140
|
478 jz waitkbd
|
pascal@18140
|
479 cbw
|
pascal@18140
|
480 int $0x16 # eat char
|
pascal@18140
|
481 movw %di, %fs # disable timeout
|
pascal@18140
|
482 incw %di # clear Z
|
pascal@18140
|
483 waitdone:
|
pascal@18140
|
484 ret
|
pascal@18140
|
485 #endif
|
pascal@18140
|
486
|
pascal@18140
|
487 #define kernel_version_offset 0xE
|
pascal@18140
|
488 puts_version:
|
pascal@18140
|
489 addw kernel_version_offset(%si),%si # starting protocol 2.00, Kernel 1.3.73
|
pascal@18140
|
490 puts:
|
pascal@18140
|
491 movb $0xd, %al # CR
|
pascal@18140
|
492 putcs:
|
pascal@18140
|
493 call putc
|
pascal@18140
|
494 lodsb
|
pascal@18140
|
495 cmpb $0, %al # end of string is any byte <= 0
|
pascal@18140
|
496 jg putcs
|
pascal@18140
|
497 ret
|
pascal@18140
|
498
|
pascal@18140
|
499 swap_floppy:
|
pascal@18140
|
500 #ifdef MULTI_INITRD
|
pascal@18140
|
501 .ascii "B or "
|
pascal@18140
|
502 #endif
|
pascal@18140
|
503 .ascii "Next!"
|
pascal@18140
|
504 .byte 7,13,0 # swap detection needs 13, 0
|
pascal@18140
|
505 #ifdef MULTI_INITRD
|
pascal@18140
|
506 max_timeouts:
|
pascal@18140
|
507 .byte 20
|
pascal@18140
|
508 table:
|
pascal@18140
|
509 .org cur_initrd_size_ofs
|
pascal@18140
|
510 cur_initrd_size:
|
pascal@18140
|
511 .word table
|
pascal@18140
|
512 .byte table+4-256
|
pascal@18140
|
513 #endif
|
pascal@18140
|
514 .org 0x1F1
|