| [88] | 1 | ; Project name : XTIDE Universal BIOS
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| [3] | 2 | ; Description : Functions for generating and accessing drive
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| 3 | ; information to be displayed on boot menu.
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| 4 |
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| 5 | ; Section containing code
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| 6 | SECTION .text
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| 7 |
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| 8 | ;--------------------------------------------------------------------
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| 9 | ; Creates new BOOTNFO struct for detected hard disk.
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| 10 | ;
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| 11 | ; BootInfo_CreateForHardDisk
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| 12 | ; Parameters:
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| 13 | ; DL: Drive number
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| 14 | ; DS:DI: Ptr to Disk Parameter Table
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| 15 | ; ES:SI: Ptr to 512-byte ATA information read from the drive
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| 16 | ; Returns:
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| 17 | ; ES:BX: Ptr to BOOTNFO (if successful)
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| 18 | ; CF: Cleared if BOOTNFO created succesfully
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| 19 | ; Set if any error
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| 20 | ; Corrupts registers:
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| 21 | ; AX, BX, CX, DX
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| 22 | ;--------------------------------------------------------------------
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| 23 | BootInfo_CreateForHardDisk:
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| 24 | call BootInfo_GetOffsetToBX ; ES:BX now points to new BOOTNFO
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| [100] | 25 | ; Fall to .StoreSectorCount
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| [3] | 26 |
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| 27 | ;--------------------------------------------------------------------
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| [100] | 28 | ; .StoreSectorCount
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| [3] | 29 | ; Parameters:
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| 30 | ; ES:BX: Ptr to BOOTNFO
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| 31 | ; ES:SI: Ptr to 512-byte ATA information read from the drive
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| 32 | ; DS:DI: Ptr to Disk Parameter Table
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| 33 | ; Returns:
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| [100] | 34 | ; Nothing
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| [3] | 35 | ; Corrupts registers:
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| 36 | ; AX, CX, DX
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| 37 | ;--------------------------------------------------------------------
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| [100] | 38 | .StoreSectorCount:
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| [3] | 39 | push bx
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| 40 | call AtaID_GetTotalSectorCount ; Get to BX:DX:AX
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| 41 | mov cx, bx ; Now in CX:DX:AX
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| 42 | pop bx
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| 43 | mov [es:bx+BOOTNFO.twSectCnt], ax
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| 44 | mov [es:bx+BOOTNFO.twSectCnt+2], dx
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| 45 | mov [es:bx+BOOTNFO.twSectCnt+4], cx
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| [100] | 46 | ; Fall to .StoreDriveName
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| [3] | 47 |
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| 48 | ;--------------------------------------------------------------------
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| [100] | 49 | ; .StoreDriveName
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| [3] | 50 | ; Parameters:
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| 51 | ; ES:BX: Ptr to BOOTNFO
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| 52 | ; ES:SI: Ptr to 512-byte ATA information read from the drive
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| 53 | ; DS:DI: Ptr to Disk Parameter Table
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| 54 | ; Returns:
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| 55 | ; CF: Cleared if variables stored succesfully
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| 56 | ; Set if any error
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| 57 | ; Corrupts registers:
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| 58 | ; AX, CX
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| 59 | ;--------------------------------------------------------------------
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| [100] | 60 | .StoreDriveName:
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| [3] | 61 | push ds
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| 62 | push si
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| 63 | push di
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| 64 |
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| 65 | push es
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| 66 | pop ds
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| [100] | 67 | add si, BYTE ATA1.strModel ; DS:SI now points drive name
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| 68 | lea di, [bx+BOOTNFO.szDrvName] ; ES:DI now points to name destination
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| [121] | 69 | mov cx, LEN_BOOTNFO_DRV / 2 ; Max number of WORDs allowed
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| 70 | .CopyNextWord:
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| 71 | lodsw
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| 72 | xchg al, ah ; Change endianness
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| 73 | stosw
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| 74 | loop .CopyNextWord
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| [128] | 75 | xor ax, ax ; Zero AX and clear CF
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| [100] | 76 | stosb ; Terminate with NULL
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| [3] | 77 |
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| 78 | pop di
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| 79 | pop si
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| 80 | pop ds
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| 81 | ret
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| 82 |
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| 83 |
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| 84 | ;--------------------------------------------------------------------
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| [100] | 85 | ; Finds BOOTNFO for drive and returns total sector count.
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| [3] | 86 | ;
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| 87 | ; BootInfo_GetTotalSectorCount
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| 88 | ; Parameters:
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| 89 | ; DL: Drive number
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| 90 | ; DS: RAMVARS segment
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| 91 | ; Returns:
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| 92 | ; BX:DX:AX: 48-bit sector count
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| 93 | ; Corrupts registers:
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| 94 | ; Nothing
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| [128] | 95 | ;--------------------------------------------------------------------
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| [3] | 96 | ALIGN JUMP_ALIGN
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| 97 | BootInfo_GetTotalSectorCount:
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| 98 | push ds
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| 99 | call BootInfo_GetOffsetToBX
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| 100 | LOAD_BDA_SEGMENT_TO ds, ax
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| 101 | mov ax, [bx+BOOTNFO.twSectCnt]
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| 102 | mov dx, [bx+BOOTNFO.twSectCnt+2]
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| 103 | mov bx, [bx+BOOTNFO.twSectCnt+4]
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| 104 | pop ds
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| 105 | ret
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| [100] | 106 |
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| 107 |
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| 108 | ;--------------------------------------------------------------------
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| 109 | ; Returns offset to BOOTNFO for wanted drive.
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| 110 | ;
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| 111 | ; BootInfo_GetOffsetToBX
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| 112 | ; Parameters:
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| 113 | ; DL: Drive number
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| 114 | ; DS: RAMVARS segment
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| 115 | ; Returns:
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| 116 | ; BX: Offset to BOOTNFO struct
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| 117 | ; Corrupts registers:
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| 118 | ; AX
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| 119 | ;--------------------------------------------------------------------
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| 120 | ALIGN JUMP_ALIGN
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| 121 | BootInfo_GetOffsetToBX:
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| 122 | mov bl, dl ; Copy drive number to BL
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| 123 | mov al, BOOTNFO_size ; Size of struct
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| 124 | sub bl, [RAMVARS.bFirstDrv] ; Drive number to index
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| 125 | mul bl ; AX = Offset inside BOOTNFO array
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| 126 | add ax, BOOTVARS.rgBootNfo ; Add offset to BOOTNFO array
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| 127 | xchg bx, ax ; Copy result to BX
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| 128 | ret
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