[90] | 1 | ; Project name : XTIDE Universal BIOS |
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[3] | 2 | ; Description : Functions for initializing the BIOS. |
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| 3 | |
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| 4 | ; Section containing code |
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| 5 | SECTION .text |
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| 6 | |
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| 7 | ;-------------------------------------------------------------------- |
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| 8 | ; Initializes the BIOS. |
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| 9 | ; This function is called from main BIOS ROM search routine. |
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| 10 | ; |
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| 11 | ; Initialize_FromMainBiosRomSearch |
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| 12 | ; Parameters: |
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| 13 | ; Nothing |
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| 14 | ; Returns: |
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| 15 | ; Nothing |
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| 16 | ; Corrupts registers: |
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| 17 | ; Nothing |
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| 18 | ;-------------------------------------------------------------------- |
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[194] | 19 | Initialize_FromMainBiosRomSearch: ; unused entrypoint ok |
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[3] | 20 | pushf |
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| 21 | push es |
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| 22 | push ds |
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| 23 | ePUSHA |
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| 24 | |
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[90] | 25 | LOAD_BDA_SEGMENT_TO es, ax |
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[3] | 26 | call Initialize_ShouldSkip |
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[90] | 27 | jnz SHORT .SkipRomInitialization |
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[3] | 28 | |
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[90] | 29 | %ifdef USE_AT ; Early initialization on AT build |
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| 30 | call Initialize_AndDetectDrives |
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| 31 | %else ; Late initialization on XT builds |
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| 32 | call Int19hLate_InitializeInt19h |
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| 33 | %endif |
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| 34 | .SkipRomInitialization: |
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[3] | 35 | ePOPA |
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| 36 | pop ds |
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| 37 | pop es |
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| 38 | popf |
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| 39 | retf |
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| 40 | |
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| 41 | |
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| 42 | ;-------------------------------------------------------------------- |
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| 43 | ; Checks if user wants to skip ROM initialization. |
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| 44 | ; |
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| 45 | ; Initialize_ShouldSkip |
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| 46 | ; Parameters: |
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[90] | 47 | ; ES: BDA segment |
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[3] | 48 | ; Returns: |
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[90] | 49 | ; ZF: Cleared if ROM initialization is to be skipped |
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| 50 | ; Set to continue ROM initialization |
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[3] | 51 | ; Corrupts registers: |
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[90] | 52 | ; Nothing |
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[3] | 53 | ;-------------------------------------------------------------------- |
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| 54 | Initialize_ShouldSkip: |
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[90] | 55 | sti ; Enable interrupts |
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| 56 | test BYTE [es:BDA.bKBFlgs1], (1<<2) ; Clear ZF if CTRL is held down |
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[3] | 57 | ret |
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| 58 | |
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| 59 | |
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| 60 | ;-------------------------------------------------------------------- |
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| 61 | ; Initializes the BIOS variables and detects IDE drives. |
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| 62 | ; |
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| 63 | ; Initialize_AndDetectDrives |
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| 64 | ; Parameters: |
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[90] | 65 | ; ES: BDA Segment |
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[3] | 66 | ; Returns: |
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[97] | 67 | ; DS: RAMVARS segment |
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[3] | 68 | ; Corrupts registers: |
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[97] | 69 | ; All |
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[3] | 70 | ;-------------------------------------------------------------------- |
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| 71 | Initialize_AndDetectDrives: |
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[130] | 72 | call BootMenuPrint_InitializeDisplayContext |
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[3] | 73 | call DetectPrint_RomFoundAtSegment |
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| 74 | call RamVars_Initialize |
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[33] | 75 | call Interrupts_InitializeInterruptVectors |
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[3] | 76 | call DetectDrives_FromAllIDEControllers |
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[98] | 77 | ; Fall to .StoreDptPointersToIntVectors |
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[97] | 78 | |
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| 79 | ;-------------------------------------------------------------------- |
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[98] | 80 | ; .StoreDptPointersToIntVectors |
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[97] | 81 | ; Parameters: |
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| 82 | ; DS: RAMVARS segment |
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| 83 | ; ES: BDA and interrupt vector segment (zero) |
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| 84 | ; Returns: |
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| 85 | ; Nothing |
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| 86 | ; Corrupts registers: |
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| 87 | ; DX, DI |
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| 88 | ;-------------------------------------------------------------------- |
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[98] | 89 | .StoreDptPointersToIntVectors: |
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[97] | 90 | mov dl, 80h |
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[152] | 91 | call RamVars_IsDriveHandledByThisBIOS |
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| 92 | jnc SHORT .FindForDrive81h ; Store nothing if not our drive |
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[97] | 93 | call FindDPT_ForDriveNumber ; DPT to DS:DI |
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[152] | 94 | mov [es:HD0_DPT_POINTER_41h*4], di |
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| 95 | mov [es:HD0_DPT_POINTER_41h*4+2], ds |
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[97] | 96 | .FindForDrive81h: |
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| 97 | inc dx |
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[152] | 98 | call RamVars_IsDriveHandledByThisBIOS |
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| 99 | jnc SHORT .ResetDetectedDrives |
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[97] | 100 | call FindDPT_ForDriveNumber |
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[152] | 101 | mov [es:HD1_DPT_POINTER_46h*4], di |
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| 102 | mov [es:HD1_DPT_POINTER_46h*4+2], ds |
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[33] | 103 | ; Fall to .ResetDetectedDrives |
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[3] | 104 | |
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| 105 | ;-------------------------------------------------------------------- |
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[97] | 106 | ; .ResetDetectedDrives |
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[3] | 107 | ; Parameters: |
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| 108 | ; DS: RAMVARS segment |
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| 109 | ; Returns: |
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| 110 | ; Nothing |
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| 111 | ; Corrupts registers: |
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[150] | 112 | ; All |
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[3] | 113 | ;-------------------------------------------------------------------- |
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[33] | 114 | .ResetDetectedDrives: |
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[150] | 115 | call Idepack_FakeToSSBP |
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| 116 | call AH0h_ResetHardDisksHandledByOurBIOS |
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[158] | 117 | add sp, BYTE EXTRA_BYTES_FOR_INTPACK |
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[150] | 118 | ret |
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