| 1 | ; Project name : XTIDE Universal BIOS
|
|---|
| 2 | ; Description : Functions for creating Disk Parameter Table.
|
|---|
| 3 |
|
|---|
| 4 | ; Section containing code
|
|---|
| 5 | SECTION .text
|
|---|
| 6 |
|
|---|
| 7 | ;--------------------------------------------------------------------
|
|---|
| 8 | ; Creates new Disk Parameter Table for detected hard disk.
|
|---|
| 9 | ; Drive is then fully accessible using any BIOS function.
|
|---|
| 10 | ;
|
|---|
| 11 | ; CreateDPT_FromAtaInformation
|
|---|
| 12 | ; Parameters:
|
|---|
| 13 | ; BH: Drive Select byte for Drive and Head Register
|
|---|
| 14 | ; ES:SI: Ptr to 512-byte ATA information read from the drive
|
|---|
| 15 | ; CS:BP: Ptr to IDEVARS for the controller
|
|---|
| 16 | ; DS: RAMVARS segment
|
|---|
| 17 | ; ES: BDA Segment
|
|---|
| 18 | ; Returns:
|
|---|
| 19 | ; DL: Drive number for new drive
|
|---|
| 20 | ; DS:DI: Ptr to Disk Parameter Table (if succesfull)
|
|---|
| 21 | ; CF: Cleared if DPT created successfully
|
|---|
| 22 | ; Set if any error
|
|---|
| 23 | ; Corrupts registers:
|
|---|
| 24 | ; AX, BX, CX, DH
|
|---|
| 25 | ;--------------------------------------------------------------------
|
|---|
| 26 | CreateDPT_FromAtaInformation:
|
|---|
| 27 | call FindDPT_ForNewDrive ; Get new DPT to DS:DI
|
|---|
| 28 | ; Fall to .InitializeDPT
|
|---|
| 29 |
|
|---|
| 30 | ;--------------------------------------------------------------------
|
|---|
| 31 | ; .InitializeDPT
|
|---|
| 32 | ; Parameters:
|
|---|
| 33 | ; BH: Drive Select byte for Drive and Head Register
|
|---|
| 34 | ; DS:DI: Ptr to Disk Parameter Table
|
|---|
| 35 | ; CS:BP: Ptr to IDEVARS for the controller
|
|---|
| 36 | ; Returns:
|
|---|
| 37 | ; AX: Zero
|
|---|
| 38 | ; Corrupts registers:
|
|---|
| 39 | ; Nothing
|
|---|
| 40 | ;--------------------------------------------------------------------
|
|---|
| 41 | .InitializeDPT:
|
|---|
| 42 | xor ax, ax
|
|---|
| 43 | mov BYTE [di+DPT.bSize], DPT_size
|
|---|
| 44 | mov [di+DPT.wDrvNumAndFlags], ax
|
|---|
| 45 | mov BYTE [di+DPT.bReset], MASK_RESET_ALL
|
|---|
| 46 | mov [di+DPT.bIdeOff], bp
|
|---|
| 47 | mov [di+DPT.bDrvSel], bh
|
|---|
| 48 | ; Fall to .StoreDriveControlByte
|
|---|
| 49 |
|
|---|
| 50 | ;--------------------------------------------------------------------
|
|---|
| 51 | ; .StoreDriveControlByte
|
|---|
| 52 | ; Parameters:
|
|---|
| 53 | ; AX: Zero
|
|---|
| 54 | ; BH: Drive Select byte for Drive and Head Register
|
|---|
| 55 | ; DS:DI: Ptr to Disk Parameter Table
|
|---|
| 56 | ; ES:SI: Ptr to 512-byte ATA information read from the drive
|
|---|
| 57 | ; CS:BP: Ptr to IDEVARS for the controller
|
|---|
| 58 | ; Returns:
|
|---|
| 59 | ; Nothing
|
|---|
| 60 | ; Corrupts registers:
|
|---|
| 61 | ; AX
|
|---|
| 62 | ;--------------------------------------------------------------------
|
|---|
| 63 | .StoreDriveControlByte:
|
|---|
| 64 | cmp BYTE [cs:bp+IDEVARS.bIRQ], al ; Interrupts enabled?
|
|---|
| 65 | jne SHORT .CheckHeadCount
|
|---|
| 66 | or al, FLG_IDE_CTRL_nIEN ; Disable interrupts
|
|---|
| 67 | .CheckHeadCount:
|
|---|
| 68 | cmp BYTE [es:si+ATA1.wHeadCnt], 8 ; 1...8 heads?
|
|---|
| 69 | jbe SHORT .StoreDrvCtrlByteToDPT
|
|---|
| 70 | or al, FLG_IDE_CTRL_O8H ; Over 8 heads (pre-ATA)
|
|---|
| 71 | .StoreDrvCtrlByteToDPT:
|
|---|
| 72 | mov [di+DPT.bDrvCtrl], al
|
|---|
| 73 | ; Fall to .StorePCHS
|
|---|
| 74 |
|
|---|
| 75 | ;--------------------------------------------------------------------
|
|---|
| 76 | ; .StorePCHS
|
|---|
| 77 | ; Parameters:
|
|---|
| 78 | ; AH: Zero
|
|---|
| 79 | ; BH: Drive Select byte for Drive and Head Register
|
|---|
| 80 | ; DS:DI: Ptr to Disk Parameter Table
|
|---|
| 81 | ; ES:SI: Ptr to 512-byte ATA information read from the drive
|
|---|
| 82 | ; CS:BP: Ptr to IDEVARS for the controller
|
|---|
| 83 | ; Returns:
|
|---|
| 84 | ; AX: P-CHS cylinders
|
|---|
| 85 | ; BL: P-CHS heads
|
|---|
| 86 | ; BH: P-CHS sectors
|
|---|
| 87 | ; Corrupts registers:
|
|---|
| 88 | ; Nothing
|
|---|
| 89 | ;--------------------------------------------------------------------
|
|---|
| 90 | .StorePCHS:
|
|---|
| 91 | mov al, FLG_DRVPARAMS_USERCHS ; User specified CHS?
|
|---|
| 92 | call AccessDPT_TestIdeVarsFlagsForMasterOrSlaveDrive
|
|---|
| 93 | jnz SHORT .GetUserSpecifiedPCHS
|
|---|
| 94 | call AtaID_GetPCHS ; Get from ATA information
|
|---|
| 95 | jmp SHORT .StorePCHStoDPT
|
|---|
| 96 |
|
|---|
| 97 | .GetUserSpecifiedPCHS:
|
|---|
| 98 | call AccessDPT_GetPointerToDRVPARAMStoCSBX
|
|---|
| 99 | mov ax, [cs:bx+DRVPARAMS.wCylinders]
|
|---|
| 100 | mov bx, [cs:bx+DRVPARAMS.wHeadsAndSectors]
|
|---|
| 101 | or BYTE [di+DPT.bFlags], FLG_DPT_USERCHS
|
|---|
| 102 |
|
|---|
| 103 | .StorePCHStoDPT:
|
|---|
| 104 | mov [di+DPT.wPCyls], ax
|
|---|
| 105 | mov [di+DPT.wHeadsAndSectors], bx
|
|---|
| 106 | ; Fall to .StoreLCHS
|
|---|
| 107 |
|
|---|
| 108 | ;--------------------------------------------------------------------
|
|---|
| 109 | ; .StoreLCHS
|
|---|
| 110 | ; Parameters:
|
|---|
| 111 | ; AX: P-CHS cylinders
|
|---|
| 112 | ; BL: P-CHS heads
|
|---|
| 113 | ; DS:DI: Ptr to Disk Parameter Table
|
|---|
| 114 | ; ES:SI: Ptr to 512-byte ATA information read from the drive
|
|---|
| 115 | ; Returns:
|
|---|
| 116 | ; Nothing
|
|---|
| 117 | ; Corrupts registers:
|
|---|
| 118 | ; AX, BX, CX
|
|---|
| 119 | ;--------------------------------------------------------------------
|
|---|
| 120 | .StoreLCHS:
|
|---|
| 121 | xor bh, bh ; BX = P-CHS Heads (1...16)
|
|---|
| 122 | xor cx, cx
|
|---|
| 123 | .ShiftLoop:
|
|---|
| 124 | cmp ax, 1024 ; Need to shift?
|
|---|
| 125 | jbe SHORT .LimitHeadsTo255 ; If not, return
|
|---|
| 126 | inc cx ; Increment shift count
|
|---|
| 127 | shr ax, 1 ; Halve cylinders
|
|---|
| 128 | shl bx, 1 ; Double heads
|
|---|
| 129 | jmp SHORT .ShiftLoop
|
|---|
| 130 |
|
|---|
| 131 | .LimitHeadsTo255:
|
|---|
| 132 | test bh, bh ; 256 heads?
|
|---|
| 133 | jz SHORT .StoreLCHStoDPT ; If less, no correction needed
|
|---|
| 134 | dec bx ; Limit to 255 heads since DOS does not support 256 heads
|
|---|
| 135 | .StoreLCHStoDPT:
|
|---|
| 136 | mov [di+DPT.bShLtoP], cl
|
|---|
| 137 | mov [di+DPT.wLHeads], bx
|
|---|
| 138 | ; Fall to .StoreAddressing
|
|---|
| 139 |
|
|---|
| 140 | ;--------------------------------------------------------------------
|
|---|
| 141 | ; .StoreAddressing
|
|---|
| 142 | ; Parameters:
|
|---|
| 143 | ; DS:DI: Ptr to Disk Parameter Table
|
|---|
| 144 | ; ES:SI: Ptr to 512-byte ATA information read from the drive
|
|---|
| 145 | ; Returns:
|
|---|
| 146 | ; Nothing
|
|---|
| 147 | ; Corrupts registers:
|
|---|
| 148 | ; Nothing
|
|---|
| 149 | ;--------------------------------------------------------------------
|
|---|
| 150 | .StoreAddressing:
|
|---|
| 151 | cmp WORD [di+DPT.wPCyls], 1024 ; L-CHS possible? (no translation needed)
|
|---|
| 152 | jbe SHORT .StoreBlockMode ; If so, nothing needs to be changed
|
|---|
| 153 | test BYTE [di+DPT.bFlags], FLG_DPT_USERCHS
|
|---|
| 154 | jnz SHORT .StorePCHSaddressing ; Use user defined P-CHS
|
|---|
| 155 | test WORD [es:si+ATA1.wCaps], A2_wCaps_LBA
|
|---|
| 156 | jz SHORT .StorePCHSaddressing ; Use P-CHS since LBA not supported
|
|---|
| 157 | test WORD [es:si+ATA6.wSetSup83], A6_wSetSup83_LBA48
|
|---|
| 158 | jz SHORT .StoreLBA28addressing ; Use LBA-28 since LBA-48 not supported
|
|---|
| 159 | or BYTE [di+DPT.bFlags], ADDR_DPT_LBA48<<1
|
|---|
| 160 | .StoreLBA28addressing:
|
|---|
| 161 | or BYTE [di+DPT.bFlags], ADDR_DPT_LBA28<<1
|
|---|
| 162 | or BYTE [di+DPT.bDrvSel], FLG_IDE_DRVHD_LBA
|
|---|
| 163 | jmp SHORT .StoreBlockMode
|
|---|
| 164 | .StorePCHSaddressing:
|
|---|
| 165 | or BYTE [di+DPT.bFlags], ADDR_DPT_PCHS<<1
|
|---|
| 166 | ; Fall to .StoreBlockMode
|
|---|
| 167 |
|
|---|
| 168 | ;--------------------------------------------------------------------
|
|---|
| 169 | ; .StoreBlockMode
|
|---|
| 170 | ; Parameters:
|
|---|
| 171 | ; DS:DI: Ptr to Disk Parameter Table
|
|---|
| 172 | ; ES:SI: Ptr to 512-byte ATA information read from the drive
|
|---|
| 173 | ; Returns:
|
|---|
| 174 | ; Nothing
|
|---|
| 175 | ; Corrupts registers:
|
|---|
| 176 | ; AX
|
|---|
| 177 | ;--------------------------------------------------------------------
|
|---|
| 178 | .StoreBlockMode:
|
|---|
| 179 | mov al, 1 ; Minimum block size is 1 sector
|
|---|
| 180 | mov ah, [es:si+ATA1.bBlckSize] ; Load max block size in sectors
|
|---|
| 181 | mov [di+DPT.wSetAndMaxBlock], ax
|
|---|
| 182 | ; Fall to .StoreEBIOSSupport
|
|---|
| 183 |
|
|---|
| 184 | ;--------------------------------------------------------------------
|
|---|
| 185 | ; .StoreEBIOSSupport
|
|---|
| 186 | ; Parameters:
|
|---|
| 187 | ; DS:DI: Ptr to Disk Parameter Table
|
|---|
| 188 | ; ES:SI: Ptr to 512-byte ATA information read from the drive
|
|---|
| 189 | ; Returns:
|
|---|
| 190 | ; Nothing
|
|---|
| 191 | ; Corrupts registers:
|
|---|
| 192 | ; AX, BX, DX
|
|---|
| 193 | ;--------------------------------------------------------------------
|
|---|
| 194 | .StoreEBIOSSupport:
|
|---|
| 195 | test BYTE [cs:ROMVARS.wFlags], FLG_ROMVARS_FULLMODE
|
|---|
| 196 | jz SHORT .StoreDriveNumberAndUpdateDriveCount ; No EBIOS support since small DPTs needed
|
|---|
| 197 |
|
|---|
| 198 | mov bl, [di+DPT.bFlags]
|
|---|
| 199 | and bx, BYTE MASK_DPT_ADDR ; Addressing mode
|
|---|
| 200 | jmp [cs:bx+.rgwAddrJmp] ; Jump to handle addressing mode
|
|---|
| 201 | .rgwAddrJmp:
|
|---|
| 202 | dw .StoreDriveNumberAndUpdateDriveCount ; ADDR_DPT_LCHS
|
|---|
| 203 | dw .StoreDriveNumberAndUpdateDriveCount ; ADDR_DPT_PCHS
|
|---|
| 204 | dw .SupportForLBA28 ; ADDR_DPT_LBA28
|
|---|
| 205 | dw .SupportForLBA48 ; ADDR_DPT_LBA48
|
|---|
| 206 |
|
|---|
| 207 | .SupportForLBA28:
|
|---|
| 208 | sub BYTE [di+DPT.bSize], 2 ; Only 4 bytes for sector count
|
|---|
| 209 | .SupportForLBA48:
|
|---|
| 210 | add BYTE [di+DPT.bSize], EBDPT_size - DPT_size
|
|---|
| 211 | or BYTE [di+DPT.bFlags], FLG_DPT_EBIOS
|
|---|
| 212 | call AtaID_GetTotalSectorCount
|
|---|
| 213 | mov [di+EBDPT.twCapacity], ax
|
|---|
| 214 | mov [di+EBDPT.twCapacity+2], dx
|
|---|
| 215 | mov [di+EBDPT.twCapacity+4], bx
|
|---|
| 216 | ; Fall to .StoreDriveNumberAndUpdateDriveCount
|
|---|
| 217 |
|
|---|
| 218 | ;--------------------------------------------------------------------
|
|---|
| 219 | ; .StoreDriveNumberAndUpdateDriveCount
|
|---|
| 220 | ; Parameters:
|
|---|
| 221 | ; DS:DI: Ptr to Disk Parameter Table
|
|---|
| 222 | ; ES:SI: Ptr to 512-byte ATA information read from the drive
|
|---|
| 223 | ; ES: BDA Segment
|
|---|
| 224 | ; Returns:
|
|---|
| 225 | ; DL: Drive number for new drive
|
|---|
| 226 | ; CF: Cleared if DPT parameters stored successfully
|
|---|
| 227 | ; Set if any error
|
|---|
| 228 | ; Corrupts registers:
|
|---|
| 229 | ; Nothing
|
|---|
| 230 | ;--------------------------------------------------------------------
|
|---|
| 231 | .StoreDriveNumberAndUpdateDriveCount:
|
|---|
| 232 | ; Make sure that more drives can be accepted
|
|---|
| 233 | mov dl, [es:BDA.bHDCount] ; Load number of hard disks
|
|---|
| 234 | test dl, dl ; Hard disks at maximum?
|
|---|
| 235 | stc ; Assume error
|
|---|
| 236 | js SHORT .TooManyDrives ; If so, return
|
|---|
| 237 |
|
|---|
| 238 | ; Store drive number to DPT
|
|---|
| 239 | or dl, 80h ; Set bit 7 since hard disk
|
|---|
| 240 | mov [di+DPT.bDrvNum], dl ; Store drive number
|
|---|
| 241 |
|
|---|
| 242 | ; Update BDA and RAMVARS
|
|---|
| 243 | inc BYTE [es:BDA.bHDCount] ; Increment drive count to BDA
|
|---|
| 244 | call RamVars_IncrementHardDiskCount
|
|---|
| 245 | clc
|
|---|
| 246 | .TooManyDrives:
|
|---|
| 247 | ret
|
|---|
