| 1 | ; Project name : XTIDE Universal BIOS
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| 2 | ; Description : Defines for DPT structs containing custom
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| 3 | ; Disk Parameter Table used by this BIOS.
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| 4 | %ifndef CUSTOMDPT_INC
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| 5 | %define CUSTOMDPT_INC
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| 6 |
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| 7 | ; Base DPT for all device types
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| 8 | struc DPT ; 10 bytes
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| 9 | ; General Disk Parameter Table related
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| 10 | .wFlags:
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| 11 | .bFlagsLow resb 1
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| 12 | .bFlagsHigh resb 1
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| 13 | .bIdevarsOffset resb 1 ; Offset to IDEVARS for this drive
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| 14 |
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| 15 | ; IDE Drive related
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| 16 | ; .bLbaHeads and .twLbaSectors are used for LBA addressing only.
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| 17 | .bLbaHeads: resb 1 ; Number of LBA assisted heads (1...255)
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| 18 | .twLbaSectors resb 2 ; 48-bit sector count for LBA addressing
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| 19 |
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| 20 | ; .wPchsCylinders and .bPchsSectors are used for CHS addressing only.
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| 21 | .wPchsCylinders resb 2 ; Number of P-CHS Cylinders (1...16383)
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| 22 | .wPchsHeadsAndSectors:
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| 23 | .bPchsHeads resb 1 ; Number of P-CHS heads (1...16)
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| 24 | .bPchsSectors resb 1 ; Number of P-CHS Sectors per Track (1...63)
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| 25 | endstruc
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| 26 |
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| 27 | ; DPT for ATA devices
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| 28 | struc DPT_ATA ; 10 + 2 bytes = 12 bytes
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| 29 | .dpt resb DPT_size
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| 30 |
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| 31 | ; Block size is specified in sectors (1, 2, 4, 8, 16, 32, 64 or 128)
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| 32 | .wSetAndMaxBlock:
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| 33 | .bSetBlock resb 1 ; Current block size (at least 1)
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| 34 | .bMaxBlock resb 1 ; Maximum block size, 0 = block mode not supported
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| 35 | endstruc
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| 36 |
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| 37 | %ifdef MODULE_SERIAL
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| 38 | ; DPT for Serial devices
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| 39 | struc DPT_SERIAL
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| 40 | .dpt resb DPT_size
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| 41 |
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| 42 | .wSerialPortAndBaud:
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| 43 | .bSerialPort resb 1 ; Serial connection I/O port address, divided by 4
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| 44 | .bSerialBaud resb 1 ; Serial connection baud rate divisor
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| 45 | endstruc
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| 46 | %endif
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| 47 |
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| 48 | LARGEST_DPT_SIZE EQU DPT_ATA_size
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| 49 |
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| 50 |
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| 51 | ; Bit definitions for DPT.bFlagsLow
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| 52 | MASKL_DPT_CHS_SHIFT_COUNT EQU (7<<0) ; Bits 0...3, P-CHS to L-CHS bit shift count (0...4)
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| 53 | FLGL_DPT_SLAVE EQU FLG_DRVNHEAD_DRV ; (1<<4), Drive is slave drive
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| 54 | MASKL_DPT_ADDRESSING_MODE EQU (3<<5) ; Bits 5..6, Addressing Mode (bit 6 == FLG_DRVNHEAD_LBA)
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| 55 | FLGL_DPT_ENABLE_IRQ EQU (1<<7)
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| 56 |
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| 57 | ; Bit definitions for DPT.bFlagsHigh
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| 58 | FLGH_DPT_REVERSED_A0_AND_A3 EQU (1<<0) ; XTIDE mod, Address lines 0 and 3 reversed
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| 59 | FLGH_DPT_BLOCK_MODE_SUPPORTED EQU (1<<1) ; Use block transfer commands (must be bit 1!)
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| 60 | %ifdef MODULE_SERIAL
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| 61 | FLGH_DPT_SERIAL_DEVICE EQU (1<<2) ; Serial Port Device
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| 62 | %endif
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| 63 | FLGH_DPT_INTERRUPT_IN_SERVICE EQU (1<<3) ; Set when waiting for IRQ
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| 64 | FLGH_DPT_RESET_nDRDY EQU (1<<4) ; Drive ready to accept commands
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| 65 | FLGH_DPT_RESET_nINITPRMS EQU (1<<5) ; Initialize Device Parameters successful
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| 66 | FLGH_DPT_RESET_nRECALIBRATE EQU (1<<6) ; Recalibrate successful
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| 67 | FLGH_DPT_RESET_nSETBLOCK EQU (1<<7) ; Initialize Block Mode successful
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| 68 | MASKH_DPT_RESET EQU 0F0h
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| 69 |
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| 70 | FLGH_DPT_SERIAL_FLOPPY EQU (1<<4)
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| 71 | FLGH_DPT_SERIAL_FLOPPY_TYPE_MASK EQU 0e0h
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| 72 | FLGH_DPT_SERIAL_FLOPPY_TYPE_FIELD_POSITION EQU 5
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| 73 |
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| 74 | ; Addressing modes for DPT.wFlags
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| 75 | ADDRESSING_MODE_FIELD_POSITION EQU 5
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| 76 | ADDRESSING_MODE_LCHS EQU 0 ; L-CHS Addressing Mode (NORMAL in many other BIOSes)
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| 77 | ADDRESSING_MODE_PCHS EQU 1 ; P-CHS Addressing Mode (LARGE in many other BIOSes)
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| 78 | ADDRESSING_MODE_LBA28 EQU 2 ; 28-bit LBA Addressing Mode
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| 79 | ADDRESSING_MODE_LBA48 EQU 3 ; 48-bit LBA Addressing Mode
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| 80 |
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| 81 | ; Number of Sectors per Track is fixed to 63 for LBA assist calculation.
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| 82 | ; 1024 cylinders, 256 heads, 63 sectors = 8.4 GB limit (but DOS does not support more than 255 heads)
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| 83 | MAX_LCHS_CYLINDERS EQU 1024
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| 84 | LBA_ASSIST_SPT EQU 63
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| 85 |
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| 86 |
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| 87 | ;--------------------------------------------------------------------
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| 88 | ; LIMIT_LBA_CYLINDERS_IN_DXAX_TO_LCHS_CYLINDERS
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| 89 | ; Parameters:
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| 90 | ; DX:AX: Number of LBA cylinders
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| 91 | ; Returns:
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| 92 | ; AX: Number of L-CHS cylinders
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| 93 | ; Corrupts registers:
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| 94 | ; Nothing
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| 95 | ;--------------------------------------------------------------------
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| 96 | %macro LIMIT_LBA_CYLINDERS_IN_DXAX_TO_LCHS_CYLINDERS 0
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| 97 | test dx, dx
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| 98 | jnz SHORT %%LoadMaxValueToAX
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| 99 | cmp ax, MAX_LCHS_CYLINDERS
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| 100 | jbe SHORT %%NoNeedToModify
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| 101 | %%LoadMaxValueToAX:
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| 102 | mov ax, MAX_LCHS_CYLINDERS
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| 103 | %%NoNeedToModify:
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| 104 | %endmacro
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| 105 |
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| 106 |
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| 107 | %endif ; CUSTOMDPT_INC
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