source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AH0h_HReset.asm@ 274

Last change on this file since 274 was 271, checked in by aitotat@…, 13 years ago

Changes to XTIDE Universal BIOS:

  • AH=0h (Reset) should now work but our drives are no longer reset if DL belongs to foreign drive.
File size: 6.5 KB
Line 
1; Project name : XTIDE Universal BIOS
2; Description : Int 13h function AH=0h, Disk Controller Reset.
3
4; Section containing code
5SECTION .text
6
7;--------------------------------------------------------------------
8; Int 13h function AH=0h, Disk Controller Reset.
9;
10; Note: We handle all AH=0h calls, even for drives handled by other
11; BIOSes!
12;
13; AH0h_HandlerForDiskControllerReset
14; Parameters:
15; DL: Translated Drive number (ignored so all drives are reset)
16; If bit 7 is set all hard disks and floppy disks reset.
17; DS:DI: Ptr to DPT (only if DL is our drive)
18; SS:BP: Ptr to IDEPACK
19; Returns with INTPACK:
20; AH: Int 13h return status (from drive requested in DL)
21; CF: 0 if succesfull, 1 if error
22;--------------------------------------------------------------------
23ALIGN JUMP_ALIGN
24AH0h_HandlerForDiskControllerReset:
25 eMOVZX bx, dl ; Copy requested drive to BL, zero BH to assume no errors
26 call ResetFloppyDrivesWithInt40h
27
28%ifdef MODULE_SERIAL_FLOPPY
29;
30; "Reset" emulatd serial floppy drives, if any. There is nothing to actually do for this reset,
31; but record the proper error return code if one of these floppy drives is the drive requested.
32;
33 call RamVars_UnpackFlopCntAndFirstToAL
34 cbw ; Clears AH (there are flop drives) or ffh (there are not)
35 ; Either AH has success code (flop drives are present)
36 ; or it doesn't matter because we won't match drive ffh
37
38 cwd ; clears DX (there are flop drives) or ffffh (there are not)
39
40 adc dl, al ; second drive (CF set) if present
41 ; If no drive is present, this will result in ffh which
42 ; won't match a drive
43 call BackupErrorCodeFromTheRequestedDriveToBH
44 mov dl, al ; We may end up doing the first drive twice (if there is
45 call BackupErrorCodeFromTheRequestedDriveToBH ; only one drive), but doing it again is not harmful.
46%endif
47
48 test bl, bl ; If we were called with a floppy disk, then we are done,
49 jns SHORT .SkipHardDiskReset ; don't do hard disks.
50
51 call ResetForeignHardDisks
52
53 ; Resetting our hard disks will modify dl and bl such that this call must be the last in the list
54 call GetDriveNumberForForeignHardDiskHandlerToDL ; Load DPT for our drive
55 jc SHORT .SkipHardDiskReset ; Our drive not requested so let's not reset them
56 call ResetHardDisksHandledByOurBIOS
57
58.SkipHardDiskReset:
59 mov ah, bh
60 jmp Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
61
62
63;--------------------------------------------------------------------
64; ResetFloppyDrivesWithInt40h
65; Parameters:
66; BL: Requested drive (DL when entering AH=00h)
67; Returns:
68; BH: Error code from requested drive (if available)
69; Corrupts registers:
70; AX, DL, DI
71;--------------------------------------------------------------------
72ResetFloppyDrivesWithInt40h:
73 call GetDriveNumberForForeignHardDiskHandlerToDL
74 and dl, 7Fh ; Clear hard disk bit
75 xor ah, ah ; Disk Controller Reset
76 int BIOS_DISKETTE_INTERRUPT_40h
77 jmp SHORT BackupErrorCodeFromTheRequestedDriveToBH
78
79
80;--------------------------------------------------------------------
81; ResetForeignHardDisks
82; Parameters:
83; BL: Requested drive (DL when entering AH=00h)
84; DS: RAMVARS segment
85; Returns:
86; BH: Error code from requested drive (if available)
87; Corrupts registers:
88; AX, DL, DI
89;--------------------------------------------------------------------
90ResetForeignHardDisks:
91 call GetDriveNumberForForeignHardDiskHandlerToDL
92 xor ah, ah ; Disk Controller Reset
93 call Int13h_CallPreviousInt13hHandler
94;;; fall-through to BackupErrorCodeFromTheRequestedDriveToBH
95
96
97;--------------------------------------------------------------------
98; BackupErrorCodeFromTheRequestedDriveToBH
99; Parameters:
100; AH: Error code from the last resetted drive
101; DL: Drive last resetted
102; BL: Requested drive (DL when entering AH=00h)
103; Returns:
104; BH: Backuped error code
105; Corrupts registers:
106; Nothing
107;--------------------------------------------------------------------
108BackupErrorCodeFromTheRequestedDriveToBH:
109 cmp dl, bl ; Requested drive?
110 eCMOVE bh, ah
111 ret
112
113
114;--------------------------------------------------------------------
115; GetDriveNumberForForeignHardDiskHandlerToDL
116; Parameters:
117; BL: Requested drive (DL when entering AH=00h)
118; DS: RAMVARS segment
119; Returns:
120; DS:DI: Ptr to DPT if our drive
121; DL: BL if foreign drive
122; 80h if our drive
123; CF: Set if foreign drive
124; Cleared if our drive
125; Corrupts registers:
126; (DI)
127;--------------------------------------------------------------------
128GetDriveNumberForForeignHardDiskHandlerToDL:
129 mov dl, bl
130 call FindDPT_ForDriveNumberInDL
131 jc SHORT .ReturnWithForeignDriveInDL
132 mov dl, 80h ; First possible Hard Disk should be safe value
133.ReturnWithForeignDriveInDL:
134 ret
135
136
137;--------------------------------------------------------------------
138; AH0h_ResetAllOurHardDisksAtTheEndOfDriveInitialization
139; Parameters:
140; DS: RAMVARS segment
141; SS:BP: Ptr to IDEPACK
142; Returns:
143; Nothing
144; Corrupts registers:
145; AX, BX, CX, DX, SI, DI
146;--------------------------------------------------------------------
147AH0h_ResetAllOurHardDisksAtTheEndOfDriveInitialization:
148 mov bl, [RAMVARS.bFirstDrv]
149 call GetDriveNumberForForeignHardDiskHandlerToDL
150 ; Fall to ResetHardDisksHandledByOurBIOS
151
152;--------------------------------------------------------------------
153; ResetHardDisksHandledByOurBIOS
154; Parameters:
155; BL: Requested drive (DL when entering AH=00h)
156; DS:DI: Ptr to DPT for requested drive
157; SS:BP: Ptr to IDEPACK
158; Returns:
159; BH: Error code from requested drive (if available)
160; Corrupts registers:
161; AX, CX, DX, SI, DI
162;--------------------------------------------------------------------
163ResetHardDisksHandledByOurBIOS:
164 mov bl, [di+DPT.bIdevarsOffset] ; replace drive number with Idevars pointer for cmp with dl
165 mov dl, ROMVARS.ideVars0 ; starting Idevars offset
166
167 call RamVars_GetIdeControllerCountToCX ; get count of ide controllers
168 jcxz .done ; just in case bIdeCnt is zero (shouldn't be)
169.loop:
170 call FindDPT_ForIdevarsOffsetInDL ; look for the first drive on this controller, if any
171 jc .notFound
172
173 call AHDh_ResetDrive ; reset master and slave on that controller
174 call BackupErrorCodeFromTheRequestedDriveToBH ; save error code if same controller as drive from entry
175
176.notFound:
177 add dl, IDEVARS_size ; move Idevars pointer forward
178 loop .loop
179
180.done:
181 ret
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