source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Initialization/DetectDrives.asm@ 263

Last change on this file since 263 was 263, checked in by gregli@…, 13 years ago

Oops, forgot to check if it still compiled without floppy support, fixed up a couple of typos and put an ifdef back into place.

File size: 6.6 KB
Line 
1; Project name : XTIDE Universal BIOS
2; Description : Functions for detecting drive for the BIOS.
3
4; Section containing code
5SECTION .text
6
7;--------------------------------------------------------------------
8; Detects all IDE hard disks to be controlled by this BIOS.
9;
10; DetectDrives_FromAllIDEControllers
11; Parameters:
12; DS: RAMVARS segment
13; ES: BDA segment (zero)
14; Returns:
15; Nothing
16; Corrupts registers:
17; All (not segments)
18;--------------------------------------------------------------------
19DetectDrives_FromAllIDEControllers:
20 call RamVars_GetIdeControllerCountToCX
21 mov bp, ROMVARS.ideVars0 ; CS:BP now points to first IDEVARS
22
23.DriveDetectLoop: ; Loop through IDEVARS
24 push cx
25
26 mov cx, g_szDetectMaster
27 mov bh, MASK_DRVNHEAD_SET ; Select Master drive
28 call StartDetectionWithDriveSelectByteInBHandStringInAX ; Detect and create DPT + BOOTNFO
29
30 mov cx, g_szDetectSlave
31 mov bh, MASK_DRVNHEAD_SET | FLG_DRVNHEAD_DRV
32 call StartDetectionWithDriveSelectByteInBHandStringInAX
33
34 pop cx
35
36 add bp, BYTE IDEVARS_size ; Point to next IDEVARS
37
38%ifdef MODULE_SERIAL
39 jcxz .AddHardDisks ; Set to zero on .ideVarsSerialAuto iteration (if any)
40%endif
41
42 loop .DriveDetectLoop
43
44%ifdef MODULE_SERIAL
45;----------------------------------------------------------------------
46;
47; if serial drive detected, do not scan (avoids duplicate drives and isn't needed - we already have a connection)
48;
49 call FindDPT_ToDSDIforSerialDevice
50 jnc .AddHardDisks
51
52 mov bp, ROMVARS.ideVarsSerialAuto ; Point to our special IDEVARS structure, just for serial scans
53
54 mov al,[cs:ROMVARS.wFlags] ; Configurator set to always scan?
55 or al,[es:BDA.bKBFlgs1] ; Or, did the user hold down the ALT key?
56 and al,8 ; 8 = alt key depressed, same as FLG_ROMVARS_SERIAL_ALWAYSDETECT
57 jnz .DriveDetectLoop
58%endif
59
60.AddHardDisks:
61;----------------------------------------------------------------------
62;
63; Add in hard disks to BDA, finalize our Count and First variables
64;
65 mov cx, [RAMVARS.wDrvCntAndFlopCnt] ; Our count of hard disks
66 test cl, cl
67 jz .AddFloppies ; If none, nothing more to do
68
69 mov al, [es:BDA.bHDCount]
70 add cl, al ; Add our drives to the system count
71 mov [es:BDA.bHDCount], cl
72 or al, 80h ; Or in hard disk flag
73 mov [RAMVARS.bFirstDrv], al ; Store first drive number
74
75
76.AddFloppies:
77%ifdef MODULE_SERIAL_FLOPPY
78;----------------------------------------------------------------------
79;
80; Add in any emulated serial floppy drives, finalize our packed Count and First variables
81;
82 dec ch
83 mov al, ch
84 js .NoFloppies ; if no drives are present, we store 0ffh
85
86 call FloppyDrive_GetCountFromBIOS_or_BDA
87
88 push ax
89
90 add al, ch ; Add our drives to existing drive count
91 cmp al, 3 ; For BDA, max out at 4 drives (ours is zero based)
92 jl .MaxBDAFloppiesExceeded
93 mov al, 3
94.MaxBDAFloppiesExceeded:
95 eROR_IM al, 2 ; move to bits 6-7
96 inc ax ; low order bit, indicating floppy drive exists
97
98 mov ah, [es:BDA.wEquipment] ; Load Equipment WORD low byte
99 and ah, 03eh ; Mask off drive number and drives present bit
100 or al, ah ; Or in new values
101 mov [es:BDA.wEquipment], al ; and store
102
103 mov al, 1eh ; BDA pointer to Floppy DPT
104 mov si, AH8h_FloppyDPT
105 call Interrupts_InstallHandlerToVectorInALFromCSSI
106
107 pop ax
108
109 shr ch, 1 ; number of drives, 1 or 2 only, to CF flag (clear=1, set=2)
110 rcl al, 1 ; starting drive number in upper 7 bits, number of drives in low bit
111.NoFloppies:
112 mov [RAMVARS.xlateVars+XLATEVARS.bFlopCntAndFirst], al
113%endif
114
115 ret
116
117%ifndef CHECK_FOR_UNUSED_ENTRYPOINTS
118 %if FLG_ROMVARS_SERIAL_SCANDETECT != 8
119 %error "DetectDrives is currently coded to assume that FLG_ROMVARS_SERIAL_SCANDETECT is the same bit as the ALT key code in the BDA. Changes in the code will be needed if these values are no longer the same."
120 %endif
121%endif
122
123
124;--------------------------------------------------------------------
125; StartDetectionWithDriveSelectByteInBHandStringInAX
126; Parameters:
127; BH: Drive Select byte for Drive and Head Register
128; CX: Offset to "Master" or "Slave" string
129; CS:BP: Ptr to IDEVARS for the drive
130; DS: RAMVARS segment
131; ES: Zero (BDA segment)
132; Returns:
133; None
134; Corrupts registers:
135; AX, BX, CX, DX, SI, DI
136;--------------------------------------------------------------------
137StartDetectionWithDriveSelectByteInBHandStringInAX:
138 call DetectPrint_StartDetectWithMasterOrSlaveStringInAXandIdeVarsInCSBP
139 ; Fall to .ReadAtaInfoFromHardDisk
140
141;--------------------------------------------------------------------
142; .ReadAtaInfoFromHardDisk
143; Parameters:
144; BH: Drive Select byte for Drive and Head Register
145; CS:BP: Ptr to IDEVARS for the drive
146; DS: RAMVARS segment
147; ES: Zero (BDA segment)
148; Returns:
149; CF: Cleared if ATA-information read successfully
150; Set if any error
151; Corrupts registers:
152; AX, BL, CX, DX, SI, DI
153;--------------------------------------------------------------------
154.ReadAtaInfoFromHardDisk:
155 mov si, BOOTVARS.rgbAtaInfo ; ES:SI now points to ATA info location
156 push es
157 push si
158 push bx
159 call Device_IdentifyToBufferInESSIwithDriveSelectByteInBH
160 pop bx
161 pop si
162 pop es
163 jnc SHORT CreateBiosTablesForHardDisk
164 ; Fall to .ReadAtapiInfoFromDrive
165
166.ReadAtapiInfoFromDrive: ; Not yet implemented
167 ;call ReadAtapiInfoFromDrive ; Assume CD-ROM
168 ;jnc SHORT _CreateBiosTablesForCDROM
169
170 ;jmp short DetectDrives_DriveNotFound
171;;; fall-through instead of previous jmp instruction
172;--------------------------------------------------------------------
173; DetectDrives_DriveNotFound
174; Parameters:
175; Nothing
176; Returns:
177; CF: Set (from BootMenuPrint_NullTerminatedStringFromCSSIandSetCF)
178; Corrupts registers:
179; AX, SI
180;--------------------------------------------------------------------
181DetectDrives_DriveNotFound:
182 mov si, g_szNotFound
183 jmp BootMenuPrint_NullTerminatedStringFromCSSIandSetCF
184
185
186;--------------------------------------------------------------------
187; CreateBiosTablesForHardDisk
188; Parameters:
189; BH: Drive Select byte for Drive and Head Register
190; CS:BP: Ptr to IDEVARS for the drive
191; ES:SI Ptr to ATA information for the drive
192; DS: RAMVARS segment
193; ES: BDA/Bootnfo segment
194; Returns:
195; Nothing
196; Corrupts registers:
197; AX, BX, CX, DX, SI, DI
198;--------------------------------------------------------------------
199CreateBiosTablesForHardDisk:
200 call CreateDPT_FromAtaInformation
201 jc SHORT DetectDrives_DriveNotFound
202 call BootMenuInfo_CreateForHardDisk
203 jmp short DetectPrint_DriveNameFromBootnfoInESBX
204
205
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