source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/CreateDPT.asm@ 562

Last change on this file since 562 was 558, checked in by krille_n_@…, 11 years ago

Changes:

  • Building the BIOS Drive Information Tool now works again.
  • Moved all XT-CF related code to MODULE_8BIT_IDE_ADVANCED. I don't see how an XT-CF card could work without *_ADVANCED anyway but if I'm wrong, feel free to undo this. Note! The autodetection code in XTIDECFG has NOT been changed to reflect this (still relies on MODULE_8BIT_IDE).
  • Optimizations and fixes in general.
File size: 9.7 KB
Line 
1; Project name : XTIDE Universal BIOS
2; Description : Functions for creating Disk Parameter Table.
3
4;
5; XTIDE Universal BIOS and Associated Tools
6; Copyright (C) 2009-2010 by Tomi Tilli, 2011-2013 by XTIDE Universal BIOS Team.
7;
8; This program is free software; you can redistribute it and/or modify
9; it under the terms of the GNU General Public License as published by
10; the Free Software Foundation; either version 2 of the License, or
11; (at your option) any later version.
12;
13; This program is distributed in the hope that it will be useful,
14; but WITHOUT ANY WARRANTY; without even the implied warranty of
15; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16; GNU General Public License for more details.
17; Visit http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
18;
19
20; Section containing code
21SECTION .text
22
23;--------------------------------------------------------------------
24; Creates new Disk Parameter Table for detected hard disk.
25; Drive is then fully accessible using any BIOS function.
26;
27; CreateDPT_FromAtaInformation
28; Parameters:
29; BH: Drive Select byte for Drive and Head Register
30; DX: Autodetected port (for devices that support autodetection)
31; ES:SI: Ptr to 512-byte ATA information read from the drive
32; CS:BP: Ptr to IDEVARS for the controller
33; DS: RAMVARS segment
34; ES: BDA Segment
35; Returns:
36; DS:DI: Ptr to Disk Parameter Table
37; CF: Cleared
38; Corrupts registers:
39; AX, BX, CX, DX
40;--------------------------------------------------------------------
41CreateDPT_FromAtaInformation:
42 call FindDPT_ForNewDriveToDSDI
43 ; Fall to .InitializeDPT
44
45;--------------------------------------------------------------------
46; .InitializeDPT
47; Parameters:
48; BH: Drive Select byte for Drive and Head Register
49; DX: Autodetected port (for devices that support autodetection)
50; DS:DI: Ptr to Disk Parameter Table
51; CS:BP: Ptr to IDEVARS for the controller
52; Returns:
53; Nothing
54; Corrupts registers:
55; AX
56;--------------------------------------------------------------------
57.InitializeDPT:
58 call CreateDPT_StoreIdevarsOffsetAndBasePortFromCSBPtoDPTinDSDI
59 ; Fall to .StoreDriveSelectAndDriveControlByte
60
61;--------------------------------------------------------------------
62; .StoreDriveSelectAndDriveControlByte
63; Parameters:
64; BH: Drive Select byte for Drive and Head Register
65; DS:DI: Ptr to Disk Parameter Table
66; ES:SI: Ptr to 512-byte ATA information read from the drive
67; CS:BP: Ptr to IDEVARS for the controller
68; Returns:
69; Nothing
70; Corrupts registers:
71; AX
72;--------------------------------------------------------------------
73.StoreDriveSelectAndDriveControlByte:
74 mov al, bh
75 and ax, BYTE FLG_DRVNHEAD_DRV ; AL now has Master/Slave bit
76%ifdef MODULE_IRQ
77 cmp [cs:bp+IDEVARS.bIRQ], ah ; Interrupts enabled?
78 jz SHORT .StoreFlags ; If not, do not set interrupt flag
79 or al, FLGL_DPT_ENABLE_IRQ
80.StoreFlags:
81%endif
82 mov [di+DPT.wFlags], ax
83 ; Fall to .StoreCHSparametersAndAddressingMode
84
85;--------------------------------------------------------------------
86; .StoreCHSparametersAndAddressingMode
87; Parameters:
88; DS:DI: Ptr to Disk Parameter Table
89; ES:SI: Ptr to 512-byte ATA information read from the drive
90; CS:BP: Ptr to IDEVARS for the controller
91; Returns:
92; Nothing
93; Corrupts registers:
94; AX, BX, CX, DX
95;--------------------------------------------------------------------
96.StoreCHSparametersAndAddressingMode:
97 ; Apply any user limited values to ATA ID
98 call AtaID_ModifyESSIforUserDefinedLimitsAndReturnTranslateModeInDX
99
100 ; Translate P-CHS to L-CHS
101 call AtaGeometry_GetLCHStoAXBLBHfromAtaInfoInESSIwithTranslateModeInDX
102 mov [di+DPT.wLchsCylinders], ax
103 mov [di+DPT.wLchsHeadsAndSectors], bx
104 mov al, dl
105 eSHL_IM al, TRANSLATEMODE_FIELD_POSITION
106 or cl, al
107
108 ; Store P-CHS and flags
109 call AtaGeometry_GetPCHStoAXBLBHfromAtaInfoInESSI
110 dec dl ; Set ZF if TRANSLATEMODE_LARGE, SF if TRANSLATEMODE_NORMAL
111 js SHORT .NothingToChange
112 jz SHORT .LimitHeadsForLargeAddressingMode
113
114 ; Set LBA bit for Assisted LBA
115 or cl, FLGL_DPT_LBA
116 jmp SHORT .NothingToChange
117
118.LimitHeadsForLargeAddressingMode:
119 ; We cannot have 16 P-Heads heads in Revised ECHS mode (8193 or more cylinders)
120 ; but 16 heads are allowed when there are 8192 or less cylinders (ECHS).
121 ; Both of these are LARGE modes so do not confuse with NORMAL mode.
122 call AtaGeometry_IsDriveSmallEnoughForECHS
123 jc SHORT .NothingToChange
124 dec bx ; Adjust 16 P-Heads to 15
125
126.NothingToChange:
127 or [di+DPT.bFlagsLow], cl ; Shift count and addressing mode
128 mov [di+DPT.wPchsHeadsAndSectors], bx
129%ifdef MODULE_COMPATIBLE_TABLES OR MODULE_EBIOS
130 ; Store P-Cylinders here for Compatible DPTs when FLGL_DPT_LBA is not set
131 ; or when drive has over 15,482,880 sectors
132 mov [di+DPT.wPchsCylinders], ax
133%endif
134
135%ifdef MODULE_EBIOS
136 test cl, FLGL_DPT_LBA
137 jz SHORT .NoLbaSoNoEBIOS
138
139 ; Store P-Cylinders but only if we have 15,482,880 or less sectors since
140 ; we only need P-Cylinders so we can return it from AH=48h
141 call AtaGeometry_GetLbaSectorCountToBXDXAXfromAtaInfoInESSI
142 sub ax, (MAX_SECTOR_COUNT_TO_RETURN_PCHS+1) & 0FFFFh
143 sbb dx, (MAX_SECTOR_COUNT_TO_RETURN_PCHS+1) >> 16
144 sbb bx, BYTE 0
145 jnc SHORT .StoreNumberOfLbaSectors
146
147 ; Since we might have altered the default P-CHS parameters to be
148 ; presented to the drive (AH=09h), we need to calculate new
149 ; P-Cylinders. It could be read from the ATA ID after
150 ; COMMAND_INITIALIZE_DEVICE_PARAMETERS but that is too much trouble.
151 ; P-Cyls = MIN(16383*16*63, LBA sector count) / (P-Heads * P-Sectors per track)
152 call AtaGeometry_GetLbaSectorCountToBXDXAXfromAtaInfoInESSI
153 xchg cx, ax ; Sector count to DX:CX
154 mov al, [di+DPT.bPchsHeads]
155 mul BYTE [di+DPT.bPchsSectorsPerTrack]
156 xchg cx, ax
157 div cx ; AX = new P-Cylinders
158
159 ; We could remove wPchsCylinders from DPT if we calculate it on AH=48h
160 ; (and for compatible DPTs) but that would require extra code so we save ROM space instead.
161 mov [di+DPT.wPchsCylinders], ax
162
163 ; Store CHS sector count as total sector count. We must not use
164 ; LBA sector count if it is 15,482,880 or less.
165 mul cx
166 xor bx, bx
167 jmp SHORT .StoreTotalSectorsFromBXDXAX
168
169
170;--------------------------------------------------------------------
171; .StoreNumberOfLbaSectors
172; Parameters:
173; DS:DI: Ptr to Disk Parameter Table
174; ES:SI: Ptr to 512-byte ATA information read from the drive
175; CS:BP: Ptr to IDEVARS for the controller
176; Returns:
177; Nothing
178; Corrupts registers:
179; AX, BX, CX, DX
180;--------------------------------------------------------------------
181.StoreNumberOfLbaSectors:
182 ; Store LBA 28/48 total sector count
183 call AtaGeometry_GetLbaSectorCountToBXDXAXfromAtaInfoInESSI
184 or [di+DPT.bFlagsLow], cl ; LBA48 flag
185.StoreTotalSectorsFromBXDXAX:
186 mov [di+DPT.twLbaSectors], ax
187 mov [di+DPT.twLbaSectors+2], dx
188 mov [di+DPT.twLbaSectors+4], bx
189.NoLbaSoNoEBIOS:
190%endif ; MODULE_EBIOS
191 ; Fall to .StoreDeviceSpecificParameters
192
193;--------------------------------------------------------------------
194; .StoreDeviceSpecificParameters
195; Parameters:
196; DS:DI: Ptr to Disk Parameter Table
197; ES:SI: Ptr to 512-byte ATA information read from the drive
198; CS:BP: Ptr to IDEVARS for the controller
199; Returns:
200; Nothing
201; Corrupts registers:
202; AX, BX, CX, DX
203;--------------------------------------------------------------------
204.StoreDeviceSpecificParameters:
205 call Device_FinalizeDPT
206
207;----------------------------------------------------------------------
208; Update drive counts (hard and floppy)
209;----------------------------------------------------------------------
210%ifdef MODULE_SERIAL
211; Device_FinalizeDPT returns with CF set only when a floppy was found which can't happen without MODULE_SERIAL
212%ifdef MODULE_SERIAL_FLOPPY
213;
214; These two instructions serve two purposes:
215; 1. If the drive is a floppy drive (CF set), then we effectively increment the counter.
216; 2. If this is a hard disk, and there have been any floppy drives previously added, then the hard disk is
217; effectively discarded. This is more of a safety check then code that should ever normally be hit (see below).
218; Since the floppy DPT's come after the hard disk DPT's, without expensive (code size) code to relocate a DPT,
219; this was necessary. Now, this situation shouldn't happen in normal operation, for a couple of reasons:
220; A. xtidecfg always puts configured serial ports at the end of the IDEVARS list
221; B. the auto serial code is always executed last
222; C. the serial server always returns floppy drives last
223;
224 adc byte [RAMVARS.xlateVars+XLATEVARS.bFlopCreateCnt], 0
225 jnz .AllDone
226%else ; ~MODULE_SERIAL_FLOPPY
227;
228; Even without floppy support enabled, we shouldn't try to mount a floppy image as a hard disk, which
229; could lead to unpredictable results since no MBR will be present, etc. The server doesn't know that
230; floppies are supported, so it is important to still fail here if a floppy is seen during the drive scan.
231;
232 jc .AllDone
233%endif ; MODULE_SERIAL_FLOPPY
234%endif ; MODULE_SERIAL
235
236 inc BYTE [RAMVARS.bDrvCnt] ; Increment drive count to RAMVARS
237
238%ifdef MODULE_SERIAL
239.AllDone:
240 clc
241%endif
242
243 ret
244
245
246;--------------------------------------------------------------------
247; CreateDPT_StoreIdevarsOffsetAndBasePortFromCSBPtoDPTinDSDI
248; Parameters:
249; DX: Autodetected port (for devices that support autodetection)
250; DS:DI: Ptr to Disk Parameter Table
251; CS:BP: Ptr to IDEVARS for the controller
252; Returns:
253; Nothing
254; Corrupts registers:
255; AX
256;--------------------------------------------------------------------
257CreateDPT_StoreIdevarsOffsetAndBasePortFromCSBPtoDPTinDSDI:
258 mov [di+DPT.bIdevarsOffset], bp ; IDEVARS must start in first 256 bytes of ROM
259 mov ax, [cs:bp+IDEVARS.wBasePort]
260 mov [di+DPT.wBasePort], ax
261 ret
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