Changeset 173 in xtideuniversalbios for trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs
- Timestamp:
- Sep 18, 2011, 11:41:29 AM (13 years ago)
- google:author:
- aitotat@gmail.com
- Location:
- trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs
- Files:
-
- 2 edited
-
AccessDPT.asm (modified) (2 diffs)
-
CreateDPT.asm (modified) (1 diff)
Legend:
- Unmodified
- Added
- Removed
-
trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/AccessDPT.asm
r161 r173 59 59 60 60 ;-------------------------------------------------------------------- 61 ; AccessDPT_GetLCHS fromPCHS61 ; AccessDPT_GetLCHS 62 62 ; Parameters: 63 63 ; DS:DI: Ptr to Disk Parameter Table … … 67 67 ; DX: Number of L-CHS heads 68 68 ; Corrupts registers: 69 ; CX 70 ;-------------------------------------------------------------------- 71 AccessDPT_GetLCHS: 72 ; Load CHS from DPT 73 eMOVZX ax, BYTE [di+DPT.bSectors] 74 mov bx, [di+DPT.dwCylinders] 75 cwd 76 mov dl, [di+DPT.bHeads] 77 78 ; Only need to limit sectors for LBA assist 79 test BYTE [di+DPT.bFlagsLow], FLG_DRVNHEAD_LBA 80 jnz SHORT .ReturnLbaAssistedLCHS 81 82 ; P-CHS to L-CHS translation when necessary 83 jmp SHORT AccessDPT_ShiftPCHinBXDXtoLCH 84 85 .ReturnLbaAssistedLCHS: 86 cmp WORD [di+DPT.dwCylinders+2], BYTE 0 87 jz SHORT .LimitCylindersTo1024 88 mov bx, MAX_LCHS_CYLINDERS 89 .LimitCylindersTo1024: 90 MIN_U bx, MAX_LCHS_CYLINDERS 91 ret 92 93 94 ;-------------------------------------------------------------------- 95 ; AccessDPT_ShiftPCHinBXDXtoLCH 96 ; Parameters: 97 ; BX: P-CHS cylinders (1...16383) 98 ; DX: P-CHS heads (1...16) 99 ; Returns: 100 ; BX: Number of L-CHS cylinders (1...1024) 101 ; DX: Number of L-CHS heads (1...255) 102 ; CX: Number of bits shifted 103 ; Corrupts registers: 69 104 ; Nothing 70 105 ;-------------------------------------------------------------------- 71 ALIGN JUMP_ALIGN 72 AccessDPT_GetLCHSfromPCHS: 73 mov al, [di+DPT.bFlagsLow] 74 and al, MASKL_DPT_CHS_SHIFT_COUNT ; Load shift count 75 xchg cx, ax 76 mov bx, [di+DPT.wPchsCylinders] ; Load P-CHS cylinders 77 shr bx, cl ; Shift to L-CHS cylinders 78 xchg cx, ax 79 eMOVZX ax, BYTE [di+DPT.bPchsSectors] ; Load Sectors per track 80 cwd 81 mov dl, [di+DPT.bLchsHeads] ; Load L-CHS heads 106 AccessDPT_ShiftPCHinBXDXtoLCH: 107 xor cx, cx 108 .ShiftLoop: 109 cmp bx, MAX_LCHS_CYLINDERS ; Need to shift? 110 jbe SHORT .LimitHeadsTo255 ; If not, return 111 inc cx ; Increment shift count 112 shr bx, 1 ; Halve cylinders 113 shl dx, 1 ; Double heads 114 jmp SHORT .ShiftLoop 115 .LimitHeadsTo255: ; DOS does not support drives with 256 heads 116 sub dl, dh ; BH set only when 256 logical heads 117 xor dh, dh 82 118 ret 83 119 -
trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/CreateDPT.asm
r169 r173 63 63 .StoreFlags: 64 64 mov [di+DPT.wFlags], ax 65 ; Fall to .Store PCHS66 67 ;-------------------------------------------------------------------- 68 ; .Store PCHS69 ; Parameters: 70 ; BH: Drive Select byte for Drive and Head Register71 ; DS:DI: Ptr to Disk Parameter Table72 ; ES:SI: Ptr to 512-byte ATA information read from the drive73 ; CS:BP: Ptr to IDEVARS for the controller74 ; Returns:75 ; AX: P-CHS cylinders76 ; BL: P-CHSheads77 ; BH: P-CHS sectors78 ; Corrupts registers:79 ; Nothing80 ;-------------------------------------------------------------------- 81 .StorePCHS: 65 ; Fall to .StoreAddressing 66 67 ;-------------------------------------------------------------------- 68 ; .StoreAddressing 69 ; Parameters: 70 ; DS:DI: Ptr to Disk Parameter Table 71 ; ES:SI: Ptr to 512-byte ATA information read from the drive 72 ; CS:BP: Ptr to IDEVARS for the controller 73 ; Returns: 74 ; DX:AX or AX: Number of cylinders 75 ; BH: Number of sectors per track 76 ; BL: Number of heads 77 ; Corrupts registers: 78 ; CX, (DX) 79 ;-------------------------------------------------------------------- 80 .StoreAddressing: 81 ; Check if CHS defined in ROMVARS 82 82 mov al, FLG_DRVPARAMS_USERCHS ; User specified CHS? 83 83 call AccessDPT_TestIdeVarsFlagsForMasterOrSlaveDrive 84 jnz SHORT .GetUserSpecifiedPCHS 84 jnz SHORT .StoreUserDefinedCHSaddressing 85 86 ; Check if LBA supported 85 87 call AtaID_GetPCHStoAXBLBHfromAtaInfoInESSI 86 jmp SHORT .StorePCHStoDPT 87 88 .GetUserSpecifiedPCHS: 88 test BYTE [es:si+ATA1.wCaps+1], A1_wCaps_LBA>>8 89 jz SHORT .StoreCHSaddressing 90 91 ; Check if 48-bit LBA supported 92 test BYTE [es:si+ATA6.wSetSup83+1], A6_wSetSup83_LBA48>>8 93 jz SHORT .StoreLBA28addressing 94 or BYTE [di+DPT.bFlagsLow], ADDRESSING_MODE_LBA48<<ADDRESSING_MODE_FIELD_POSITION 95 .StoreLBA28addressing: 96 or BYTE [di+DPT.bFlagsLow], ADDRESSING_MODE_LBA28<<ADDRESSING_MODE_FIELD_POSITION 97 call AtaID_GetTotalSectorCountToBXDXAXfromAtaInfoInESSI 98 call AtaID_GetLbaAssistedCHStoDXAXBLBH 99 jmp SHORT .StoreChsFromDXAXBX 100 101 ; Check if P-CHS to L-CHS translation required 102 .StoreUserDefinedCHSaddressing: 89 103 call AccessDPT_GetPointerToDRVPARAMStoCSBX 90 104 mov ax, [cs:bx+DRVPARAMS.wCylinders] 91 105 mov bx, [cs:bx+DRVPARAMS.wHeadsAndSectors] 92 93 .StorePCHStoDPT: 94 mov [di+DPT.wPchsCylinders], ax 95 mov [di+DPT.wPchsHeadsAndSectors], bx 96 ; Fall to .StoreLCHS 97 98 ;-------------------------------------------------------------------- 99 ; .StoreLCHS 100 ; Parameters: 101 ; AX: P-CHS cylinders 102 ; BL: P-CHS heads 103 ; DS:DI: Ptr to Disk Parameter Table 104 ; ES:SI: Ptr to 512-byte ATA information read from the drive 105 ; CS:BP: Ptr to IDEVARS for the controller 106 ; Returns: 107 ; Nothing 108 ; Corrupts registers: 109 ; AX, BX, CX 110 ;-------------------------------------------------------------------- 111 .StoreLCHS: 112 xor bh, bh ; BX = P-CHS Heads (1...16) 113 xor cx, cx 114 .ShiftLoop: 115 cmp ax, 1024 ; Need to shift? 116 jbe SHORT .LimitHeadsTo255 ; If not, return 117 inc cx ; Increment shift count 118 shr ax, 1 ; Halve cylinders 119 shl bx, 1 ; Double heads 120 jmp SHORT .ShiftLoop 121 122 .LimitHeadsTo255: ; DOS does not support drives with 256 heads 123 rcr bh, 1 ; Set CF if 256 heads 124 sbb bl, 0 ; Decrement to 255 if 256 heads 125 or [di+DPT.wFlags], cl 126 mov [di+DPT.bLchsHeads], bl 127 ; Fall to .StoreAddressing 128 129 ;-------------------------------------------------------------------- 130 ; .StoreAddressing 131 ; Parameters: 132 ; DS:DI: Ptr to Disk Parameter Table 133 ; ES:SI: Ptr to 512-byte ATA information read from the drive 134 ; CS:BP: Ptr to IDEVARS for the controller 135 ; Returns: 136 ; Nothing 137 ; Corrupts registers: 138 ; AX, BX 139 ;-------------------------------------------------------------------- 140 .StoreAddressing: 141 ; Check if L-CHS addressing should be used 142 cmp WORD [di+DPT.wPchsCylinders], 1024 ; L-CHS possible? (no translation needed) 143 jbe SHORT .StoreBlockMode ; If so, nothing needs to be changed 144 145 ; Check if P-CHS addressing should be used 146 mov al, FLG_DRVPARAMS_USERCHS ; User specified CHS? 147 call AccessDPT_TestIdeVarsFlagsForMasterOrSlaveDrive 148 jnz SHORT .StorePCHSaddressing 149 test WORD [es:si+ATA1.wCaps], A2_wCaps_LBA 150 jz SHORT .StorePCHSaddressing ; Use P-CHS since LBA not supported 151 152 ; LBA needs to be used. Check if 48-bit LBA is supported 153 test WORD [es:si+ATA6.wSetSup83], A6_wSetSup83_LBA48 154 jz SHORT .StoreLBA28addressing ; Use LBA-28 since LBA-48 not supported 155 or BYTE [di+DPT.wFlags], ADDRESSING_MODE_LBA48<<ADDRESSING_MODE_FIELD_POSITION 156 .StoreLBA28addressing: 157 or BYTE [di+DPT.wFlags], ADDRESSING_MODE_LBA28<<ADDRESSING_MODE_FIELD_POSITION 158 jmp SHORT .StoreBlockMode 159 .StorePCHSaddressing: 160 or BYTE [di+DPT.wFlags], ADDRESSING_MODE_PCHS<<ADDRESSING_MODE_FIELD_POSITION 106 .StoreCHSaddressing: 107 cmp ax, MAX_LCHS_CYLINDERS 108 jbe SHORT .StoreChsFromAXBX ; No translation required 109 110 ; We need to get number of bits to shift for translation 111 push bx 112 push ax 113 eMOVZX dx, bl ; Heads now in DX 114 xchg bx, ax ; Sectors now in BX 115 call AccessDPT_ShiftPCHinBXDXtoLCH 116 or cl, ADDRESSING_MODE_PCHS<<ADDRESSING_MODE_FIELD_POSITION 117 or [di+DPT.bFlagsLow], cl ; Store bits to shift 118 pop ax 119 pop bx 120 ; Fall to .StoreChsFromAXBX 121 122 ;-------------------------------------------------------------------- 123 ; .StoreChsFromAXBX 124 ; .StoreChsFromDXAXBX 125 ; Parameters: 126 ; DX:AX or AX: Number of cylinders 127 ; BH: Number of sectors per track 128 ; BL: Number of heads 129 ; DS:DI: Ptr to Disk Parameter Table 130 ; ES:SI: Ptr to 512-byte ATA information read from the drive 131 ; CS:BP: Ptr to IDEVARS for the controller 132 ; Returns: 133 ; Nothing 134 ; Corrupts registers: 135 ; DX 136 ;-------------------------------------------------------------------- 137 .StoreChsFromAXBX: 138 xor dx, dx 139 .StoreChsFromDXAXBX: 140 mov [di+DPT.dwCylinders], ax 141 mov [di+DPT.dwCylinders+2], dx 142 mov [di+DPT.wHeadsAndSectors], bx 161 143 ; Fall to .StoreBlockMode 162 144
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