source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AH0h_HReset.asm@ 28

Last change on this file since 28 was 28, checked in by Tomi Tilli, 14 years ago
  • v1.1.1 broke booting from foreign drives, it is now fixed.
  • Improved error handling a bit.
  • Longer DRQ and IRQ timeouts to minimize write timouts with some (bad) CF cards.
  • Default boot menu drive should now be properly selected.
File size: 5.8 KB
RevLine 
[3]1; File name : AH0h_HReset.asm
2; Project name : IDE BIOS
3; Created date : 27.9.2007
[28]4; Last update : 29.7.2010
[3]5; Author : Tomi Tilli
6; Description : Int 13h function AH=0h, Disk Controller Reset.
7
8RETRIES_IF_RESET_FAILS EQU 3
9TIMEOUT_BEFORE_RESET_RETRY EQU 5 ; System timer ticks
10
11; Section containing code
12SECTION .text
13
14;--------------------------------------------------------------------
15; Int 13h function AH=0h, Disk Controller Reset.
16;
17; AH0h_HandlerForDiskControllerReset
18; Parameters:
19; AH: Bios function 0h
20; DL: Drive number (ignored so all drives are reset)
21; If bit 7 is set all hard disks and floppy disks reset.
22; Parameters loaded by Int13h_Jump:
23; DS: RAMVARS segment
24; Returns:
[23]25; AH: Int 13h return status (from drive requested in DL)
[3]26; CF: 0 if succesfull, 1 if error
27; IF: 1
28; Corrupts registers:
29; Flags
30;--------------------------------------------------------------------
31ALIGN JUMP_ALIGN
32AH0h_HandlerForDiskControllerReset:
33 push dx
34 push cx
35 push bx
36 push ax
37
[23]38 eMOVZX bx, dl ; Copy requested drive to BL, zero BH to assume no errors
[26]39 call ResetFloppyDrivesWithInt40h
40 test bl, 80h
41 jz SHORT .SkipHardDiskReset
42 call ResetForeignHardDisks
[27]43 call AH0h_ResetHardDisksHandledByOurBIOS
[23]44ALIGN JUMP_ALIGN
[26]45.SkipHardDiskReset:
[23]46 mov ah, bh ; Copy error code to AH
47 xor al, al ; Zero AL...
[27]48 cmp al, bh ; ...and set CF if error
[28]49 jmp Int13h_StoreErrorCodeToBDAandPopXRegsAndReturn
[3]50
51
52;--------------------------------------------------------------------
[26]53; ResetFloppyDrivesWithInt40h
[3]54; Parameters:
[23]55; BL: Requested drive (DL when entering AH=00h)
56; Returns:
57; BH: Error code from requested drive (if available)
58; Corrupts registers:
[27]59; AX, DL, DI
[23]60;--------------------------------------------------------------------
61ALIGN JUMP_ALIGN
[26]62ResetFloppyDrivesWithInt40h:
[27]63 call GetDriveNumberForForeignBiosesToDL
64 and dl, 7Fh ; Clear hard disk bit
[26]65 xor ah, ah ; Disk Controller Reset
[23]66 int INTV_FLOPPY_FUNC
[26]67 jmp SHORT BackupErrorCodeFromTheRequestedDriveToBH
[23]68
69
70;--------------------------------------------------------------------
[26]71; ResetForeignHardDisks
[23]72; Parameters:
73; BL: Requested drive (DL when entering AH=00h)
[3]74; DS: RAMVARS segment
75; Returns:
[23]76; BH: Error code from requested drive (if available)
[3]77; Corrupts registers:
[27]78; AX, DL, DI
[23]79;--------------------------------------------------------------------
80ALIGN JUMP_ALIGN
[26]81ResetForeignHardDisks:
[27]82 call GetDriveNumberForForeignBiosesToDL
83 xor ah, ah ; Disk Controller Reset
[23]84 pushf ; Push flags to simulate INT
85 cli ; Disable interrupts since INT does that
86 call FAR [RAMVARS.fpOldI13h]
87 sti ; Make sure interrupts are enabled again (some BIOSes fails to enable it)
[26]88 jmp SHORT BackupErrorCodeFromTheRequestedDriveToBH
[23]89
[26]90
[3]91;--------------------------------------------------------------------
[27]92; GetDriveNumberForForeignBiosesToDL
93; Parameters:
94; BL: Requested drive (DL when entering AH=00h)
95; DS: RAMVARS segment
96; Returns:
97; DL: BL if foreign drive
98; 80h if our drive
99; Corrupts registers:
100; DI
101;--------------------------------------------------------------------
102ALIGN JUMP_ALIGN
103GetDriveNumberForForeignBiosesToDL:
104 mov dl, bl
105 call RamVars_IsDriveHandledByThisBIOS
106 jc SHORT .GetFirstDriveForForeignBios
107 ret ; Return what was in BL unmodified
108ALIGN JUMP_ALIGN
109.GetFirstDriveForForeignBios:
110 mov dl, 80h
111 ret
112
113
114;--------------------------------------------------------------------
[26]115; ResetHardDisksHandledByOurBIOS
[23]116; Parameters:
117; BL: Requested drive (DL when entering AH=00h)
118; DS: RAMVARS segment
119; Returns:
120; BH: Error code from requested drive (if available)
121; Corrupts registers:
[27]122; AX, CX, DX, DI
[23]123;--------------------------------------------------------------------
[3]124ALIGN JUMP_ALIGN
[27]125AH0h_ResetHardDisksHandledByOurBIOS:
[26]126 mov dh, [RAMVARS.bDrvCnt] ; Load drive count to DH
127 test dh, dh
128 jz SHORT .AllDrivesReset ; Return if no drives
129 mov dl, [RAMVARS.bFirstDrv] ; Load number of first our drive
130 add dh, dl ; DH = one past last drive to reset
[3]131ALIGN JUMP_ALIGN
[26]132.DriveResetLoop:
133 call AHDh_ResetDrive
[27]134 call .BackupErrorCodeFromMasterOrSlaveToBH
[26]135 inc dx
136 cmp dl, dh ; All done?
137 jb SHORT .DriveResetLoop ; If not, reset next drive
138.AllDrivesReset:
[3]139 ret
140
141;--------------------------------------------------------------------
[27]142; .BackupErrorCodeFromMasterOrSlaveToBH
[3]143; Parameters:
[27]144; AH: Error code for drive DL reset
145; BL: Requested drive (DL when entering AH=00h)
[26]146; DL: Drive just resetted
[3]147; DS: RAMVARS segment
148; Returns:
[27]149; BH: Backuped error code
[26]150; DL: Incremented if next drive is slave drive
151; (=already resetted)
[3]152; Corrupts registers:
[27]153; CX, DI
[3]154;--------------------------------------------------------------------
155ALIGN JUMP_ALIGN
[27]156.BackupErrorCodeFromMasterOrSlaveToBH:
157 call BackupErrorCodeFromTheRequestedDriveToBH
158 mov cx, [RAMVARS.wIdeBase] ; Load base port for resetted drive
[26]159
[27]160 inc dx ; DL to next drive
161 call FindDPT_ForDriveNumber ; Get DPT to DS:DI, store port to RAMVARS
162 jnc SHORT .NoMoreDrivesOrNoSlaveDrive
163 cmp cx, [RAMVARS.wIdeBase] ; Next drive is from same controller?
164 je SHORT BackupErrorCodeFromTheRequestedDriveToBH
165.NoMoreDrivesOrNoSlaveDrive:
166 dec dx
[3]167 ret
168
169
170;--------------------------------------------------------------------
[26]171; BackupErrorCodeFromTheRequestedDriveToBH
[3]172; Parameters:
[23]173; AH: Error code from the last resetted drive
174; DL: Drive last resetted
175; BL: Requested drive (DL when entering AH=00h)
[3]176; Returns:
[23]177; BH: Backuped error code
[3]178; Corrupts registers:
179; Nothing
180;--------------------------------------------------------------------
181ALIGN JUMP_ALIGN
[26]182BackupErrorCodeFromTheRequestedDriveToBH:
183 cmp dl, bl ; Requested drive?
[23]184 jne SHORT .Return
185 mov bh, ah
186ALIGN JUMP_ALIGN
187.Return:
[3]188 ret
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