source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/CreateDPT.asm@ 541

Last change on this file since 541 was 535, checked in by aitotat@…, 12 years ago

Changes to XTIDE Universal BIOS:

  • AH=48h now returns Device Parameter Table Extension when RETURN_DPTE_ON_AH48H is defined.
  • Removed few unnecessary instructions from hardware interrupt handler.
  • P-Cylinders returned by AH=48h are no longer calculated from L-CHS capacity.
File size: 12.1 KB
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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 (if successful)
37; CF: Cleared if DPT created successfully
38; Set if any error
39; Corrupts registers:
40; AX, BX, CX, DH
41;--------------------------------------------------------------------
42CreateDPT_FromAtaInformation:
43 call FindDPT_ForNewDriveToDSDI
44 ; Fall to .InitializeDPT
45
46;--------------------------------------------------------------------
47; .InitializeDPT
48; Parameters:
49; BH: Drive Select byte for Drive and Head Register
50; DX: Autodetected port (for devices that support autodetection)
51; DS:DI: Ptr to Disk Parameter Table
52; CS:BP: Ptr to IDEVARS for the controller
53; Returns:
54; Nothing
55; Corrupts registers:
56; AX
57;--------------------------------------------------------------------
58.InitializeDPT:
59 call CreateDPT_StoreIdevarsOffsetAndBasePortFromCSBPtoDPTinDSDI
60 ; Fall to .StoreDriveSelectAndDriveControlByte
61
62;--------------------------------------------------------------------
63; .StoreDriveSelectAndDriveControlByte
64; Parameters:
65; BH: Drive Select byte for Drive and Head Register
66; DS:DI: Ptr to Disk Parameter Table
67; ES:SI: Ptr to 512-byte ATA information read from the drive
68; CS:BP: Ptr to IDEVARS for the controller
69; Returns:
70; Nothing
71; Corrupts registers:
72; AX
73;--------------------------------------------------------------------
74.StoreDriveSelectAndDriveControlByte:
75 mov al, bh
76 and ax, BYTE FLG_DRVNHEAD_DRV ; AL now has Master/Slave bit
77%ifdef MODULE_IRQ
78 cmp [cs:bp+IDEVARS.bIRQ], ah ; Interrupts enabled?
79 jz SHORT .StoreFlags ; If not, do not set interrupt flag
80 or al, FLGL_DPT_ENABLE_IRQ
81.StoreFlags:
82%endif
83 mov [di+DPT.wFlags], ax
84 ; Fall to .StoreCHSparametersAndAddressingMode
85
86;--------------------------------------------------------------------
87; .StoreCHSparametersAndAddressingMode
88; Parameters:
89; DS:DI: Ptr to Disk Parameter Table
90; ES:SI: Ptr to 512-byte ATA information read from the drive
91; CS:BP: Ptr to IDEVARS for the controller
92; Returns:
93; Nothing
94; Corrupts registers:
95; AX, BX, CX, DX
96;--------------------------------------------------------------------
97.StoreCHSparametersAndAddressingMode:
98 ; Check if CHS defined in ROMVARS
99 call GetUserDefinedCapacityToBXAXandFlagsToCXandModeToDXfromROMVARS
100 test cl, FLG_DRVPARAMS_USERCHS
101 jz SHORT .AutodetectPCHSvalues
102
103 ; Translate P-CHS to L-CHS
104 call AtaGeometry_GetLCHStoAXBLBHfromPCHSinAXBLBHandTranslateModeInDX
105 jmp SHORT .StoreLCHStoDPT
106.AutodetectPCHSvalues:
107 call AtaGeometry_GetLCHStoAXBLBHfromAtaInfoInESSIandTranslateModeInDX
108
109.StoreLCHStoDPT:
110 eSHL_IM dl, TRANSLATEMODE_FIELD_POSITION
111 or cl, dl
112 or [di+DPT.bFlagsLow], cl ; Shift count and addressing mode
113 mov [di+DPT.wLchsCylinders], ax
114 mov [di+DPT.wLchsHeadsAndSectors], bx
115
116 ; Store P-CHS to DPT
117 call AtaGeometry_GetPCHStoAXBLBHfromAtaInfoInESSI
118 mov [di+DPT.bPchsHeads], bl
119%ifdef MODULE_EBIOS
120 mov [di+DPT.bPchsSectorsPerTrack], bh
121
122; This is what Award BIOS from 1997 Pentium motherboard does. I can't think
123; of any good reason to do the same but let's keep this here just in case,
124; at least for a while.
125%if 0
126%ifdef RESERVE_DIAGNOSTIC_CYLINDER
127 ; Do not store P-Cylinders, instead calculate it from L-CHS total sector count.
128 ; Read AH=48h_GetExtendedDriveParameters.asm for more info.
129 xchg ax, bx
130 mul ah
131 push ax ; P-Heads * P-Sectors per track
132 call AH15h_GetSectorCountToBXDXAX
133 pop bx
134 div bx ; AX = Calculated cylinders
135%endif ; RESERVE_DIAGNOSTIC_CYLINDER
136%endif ; 0
137
138 mov [di+DPT.wPchsCylinders], ax
139 ; Fall to .StoreNumberOfLbaSectors
140
141;--------------------------------------------------------------------
142; .StoreNumberOfLbaSectors
143; Parameters:
144; DS:DI: Ptr to Disk Parameter Table
145; ES:SI: Ptr to 512-byte ATA information read from the drive
146; CS:BP: Ptr to IDEVARS for the controller
147; Returns:
148; Nothing
149; Corrupts registers:
150; AX, BX, CX, DX
151;--------------------------------------------------------------------
152 ; Check if LBA supported
153 test BYTE [es:si+ATA1.wCaps+1], A1_wCaps_LBA>>8
154 jz SHORT .NoLbaSupportedSoNoEBIOS
155
156 ; Store LBA 28/48 total sector count
157 call AtaGeometry_GetLbaSectorCountToBXDXAXfromAtaInfoInESSI
158 call StoreLba48AddressingFromCLandTotalSectorCountFromBXDXAX
159
160 ; If we have 15,482,880 or less sectors, we multiply P-CHS values
161 ; and use that as total sector count.
162 ; Read AH=48h_GetExtendedDriveParameters.asm for more info.
163 sub ax, 4001h
164 sbb dx, 0ECh
165 sbb bx, BYTE 0
166 jnc SHORT .NoNeedToUseCHSsectorCount ; More than EC4000h
167
168 mov al, [di+DPT.bPchsHeads]
169 mul BYTE [di+DPT.bPchsSectorsPerTrack]
170 mul WORD [di+DPT.wPchsCylinders]
171 xor bx, bx
172 call StoreLba48AddressingFromCLandTotalSectorCountFromBXDXAX
173
174 ; Load user defined LBA
175.NoNeedToUseCHSsectorCount:
176 call GetUserDefinedCapacityToBXAXandFlagsToCXandModeToDXfromROMVARS
177 test cl, FLG_DRVPARAMS_USERLBA
178 jz SHORT .KeepTotalSectorsFromAtaID
179
180 ; Compare user defined and ATA-ID sector count and select smaller
181 mov dx, bx
182 xor bx, bx ; User defined LBA now in BX:DX:AX
183 cmp bx, [di+DPT.twLbaSectors+4]
184 jb SHORT .StoreUserDefinedSectorCountToDPT
185 cmp dx, [di+DPT.twLbaSectors+2]
186 jb SHORT .StoreUserDefinedSectorCountToDPT
187 ja SHORT .KeepTotalSectorsFromAtaID
188 cmp ax, [di+DPT.twLbaSectors]
189 jae SHORT .KeepTotalSectorsFromAtaID
190.StoreUserDefinedSectorCountToDPT:
191 ; CL bit FLGL_DPT_LBA48 is clear at this point
192 call StoreLba48AddressingFromCLandTotalSectorCountFromBXDXAX
193
194.KeepTotalSectorsFromAtaID:
195.NoLbaSupportedSoNoEBIOS:
196%endif ; MODULE_EBIOS
197 ; Fall to .StoreBlockMode
198
199;--------------------------------------------------------------------
200; .StoreBlockMode
201; Parameters:
202; DS:DI: Ptr to Disk Parameter Table
203; ES:SI: Ptr to 512-byte ATA information read from the drive
204; CS:BP: Ptr to IDEVARS for the controller
205; Returns:
206; Nothing
207; Corrupts registers:
208; Nothing
209;--------------------------------------------------------------------
210.StoreBlockMode:
211 cmp BYTE [es:si+ATA1.bBlckSize], 1 ; Max block size in sectors
212 jbe SHORT .BlockModeTransfersNotSupported
213 or BYTE [di+DPT.bFlagsHigh], FLGH_DPT_BLOCK_MODE_SUPPORTED
214.BlockModeTransfersNotSupported:
215 ; Fall to .StoreDeviceSpecificParameters
216
217;--------------------------------------------------------------------
218; .StoreDeviceSpecificParameters
219; Parameters:
220; DS:DI: Ptr to Disk Parameter Table
221; ES:SI: Ptr to 512-byte ATA information read from the drive
222; CS:BP: Ptr to IDEVARS for the controller
223; Returns:
224; Nothing
225; Corrupts registers:
226; AX, BX, CX, DX
227;--------------------------------------------------------------------
228.StoreDeviceSpecificParameters:
229 call Device_FinalizeDPT
230
231;----------------------------------------------------------------------
232; Update drive counts (hard and floppy)
233;----------------------------------------------------------------------
234
235%ifdef MODULE_SERIAL_FLOPPY
236;
237; These two instructions serve two purposes:
238; 1. If the drive is a floppy drive (CF set), then we effectively increment the counter.
239; 2. If this is a hard disk, and there have been any floppy drives previously added, then the hard disk is
240; effectively discarded. This is more of a safety check then code that should ever normally be hit (see below).
241; Since the floppy DPT's come after the hard disk DPT's, without expensive (code size) code to relocate a DPT,
242; this was necessary. Now, this situation shouldn't happen in normal operation, for a couple of reasons:
243; A. xtidecfg always puts configured serial ports at the end of the IDEVARS list
244; B. the auto serial code is always executed last
245; C. the serial server always returns floppy drives last
246;
247 adc byte [RAMVARS.xlateVars+XLATEVARS.bFlopCreateCnt], 0
248 jnz .AllDone
249%else
250;
251; Even without floppy support enabled, we shouldn't try to mount a floppy image as a hard disk, which
252; could lead to unpredictable results since no MBR will be present, etc. The server doesn't know that
253; floppies are supported, so it is important to still fail here if a floppy is seen during the drive scan.
254;
255 jc .AllDone
256%endif
257
258 inc BYTE [RAMVARS.bDrvCnt] ; Increment drive count to RAMVARS
259
260.AllDone:
261 clc
262 ret
263
264
265;--------------------------------------------------------------------
266; CreateDPT_StoreIdevarsOffsetAndBasePortFromCSBPtoDPTinDSDI
267; Parameters:
268; DX: Autodetected port (for devices that support autodetection)
269; DS:DI: Ptr to Disk Parameter Table
270; CS:BP: Ptr to IDEVARS for the controller
271; Returns:
272; Nothing
273; Corrupts registers:
274; AX
275;--------------------------------------------------------------------
276CreateDPT_StoreIdevarsOffsetAndBasePortFromCSBPtoDPTinDSDI:
277 mov [di+DPT.bIdevarsOffset], bp ; IDEVARS must start in first 256 bytes of ROM
278
279%ifdef MODULE_8BIT_IDE_ADVANCED
280 call DetectDrives_DoesIdevarsInCSBPbelongToXTCF
281 jne SHORT .DeviceUsesPortSpecifiedInIDEVARS
282 mov [di+DPT.wBasePort], dx
283 ret
284.DeviceUsesPortSpecifiedInIDEVARS:
285%endif ; MODULE_8BIT_IDE_ADVANCED
286
287 mov ax, [cs:bp+IDEVARS.wBasePort]
288 mov [di+DPT.wBasePort], ax
289 ret
290
291
292;--------------------------------------------------------------------
293; GetUserDefinedCapacityToBXAXandFlagsToCXandModeToDXfromROMVARS
294; Parameters:
295; DS:DI: Ptr to Disk Parameter Table
296; Returns:
297; AX: User defined P-CHS Cylinders or LBA low word
298; BX: User defined P-CHS Heads and Sectors or LBA high word
299; DX: Translate mode or TRANSLATEMODE_AUTO
300; CX: FLG_DRVPARAMS_USERCHS if user defined CHS in BX:AX
301; FLG_DRVPARAMS_USERLBA if user defined LBA in BX:AX
302; Zero if user has not defined capacity
303; Corrupts registers:
304; Nothing
305;--------------------------------------------------------------------
306GetUserDefinedCapacityToBXAXandFlagsToCXandModeToDXfromROMVARS:
307 call AccessDPT_GetPointerToDRVPARAMStoCSBX
308
309 ; Get settings
310 mov cx, [cs:bx+DRVPARAMS.wFlags]
311 mov dx, cx
312 and cx, BYTE FLG_DRVPARAMS_USERCHS | FLG_DRVPARAMS_USERLBA
313 and dx, BYTE MASK_DRVPARAMS_TRANSLATEMODE
314 eSHR_IM dx, TRANSLATEMODE_FIELD_POSITION
315
316 ; Get capacity
317 mov ax, [cs:bx+DRVPARAMS.wCylinders] ; Or .dwMaximumLBA
318 mov bx, [cs:bx+DRVPARAMS.wHeadsAndSectors] ; Or .dwMaximumLBA+2
319 ret
320
321
322%ifdef MODULE_EBIOS
323;--------------------------------------------------------------------
324; StoreLba48AddressingFromCLandTotalSectorCountFromBXDXAX
325; Parameters:
326; BX:DX:AX: Total Sector Count
327; CL: FLGL_DPT_LBA48 if LBA48 supported
328; DS:DI: Ptr to Disk Parameter Table
329; Returns:
330; Nothing
331; Corrupts registers:
332; CL
333;--------------------------------------------------------------------
334StoreLba48AddressingFromCLandTotalSectorCountFromBXDXAX:
335 or cl, FLGL_DPT_LBA_AND_EBIOS_SUPPORTED
336 and BYTE [di+DPT.bFlagsLow], ~FLGL_DPT_LBA48
337 or [di+DPT.bFlagsLow], cl
338 mov [di+DPT.twLbaSectors], ax
339 mov [di+DPT.twLbaSectors+2], dx
340 mov [di+DPT.twLbaSectors+4], bx
341 ret
342%endif ; MODULE_EBIOS
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