source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Initialization/DetectDrives.asm@ 165

Last change on this file since 165 was 150, checked in by Tomi Tilli, 13 years ago

Changes to XTIDE Universal BIOS:

  • Redesigned Disk Parameter Tables.
  • Code generalizations for supporting non-IDE devices in the future.
File size: 3.8 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.DriveDetectLoop:
23 call DetectDrives_WithIDEVARS ; Detect Master and Slave
24 add bp, BYTE IDEVARS_size ; Point to next IDEVARS
25 loop .DriveDetectLoop
26 ret
27
28
29;--------------------------------------------------------------------
30; Detects IDE hard disks by using information from IDEVARS.
31;
32; DetectDrives_WithIDEVARS
33; Parameters:
34; CS:BP: Ptr to IDEVARS
35; DS: RAMVARS segment
36; ES: Zero (BDA segment)
37; Returns:
38; Nothing
39; Corrupts registers:
40; AX, BX, DX, SI, DI
41;--------------------------------------------------------------------
42DetectDrives_WithIDEVARS:
43 push cx
44 mov ax, g_szMaster
45 mov bh, MASK_DRVNHEAD_SET ; Select Master drive
46 call StartDetectionWithDriveSelectByteInBHandStringInAX ; Detect and create DPT + BOOTNFO
47
48 mov ax, g_szSlave
49 mov bh, MASK_DRVNHEAD_SET | FLG_DRVNHEAD_DRV
50 call StartDetectionWithDriveSelectByteInBHandStringInAX
51 pop cx
52 ret
53
54
55;--------------------------------------------------------------------
56; StartDetectionWithDriveSelectByteInBHandStringInAX
57; Parameters:
58; AX: Offset to "Master" or "Slave" string
59; BH: Drive Select byte for Drive and Head Register
60; CS:BP: Ptr to IDEVARS for the drive
61; DS: RAMVARS segment
62; ES: Zero (BDA segment)
63; Returns:
64; Nothing
65; Corrupts registers:
66; AX, BX, CX, DX, SI, DI
67;--------------------------------------------------------------------
68StartDetectionWithDriveSelectByteInBHandStringInAX:
69 call DetectPrint_StartDetectWithMasterOrSlaveStringInAXandIdeVarsInCSBP
70 ; Fall to .ReadAtaInfoFromHardDisk
71
72;--------------------------------------------------------------------
73; .ReadAtaInfoFromHardDisk
74; Parameters:
75; BH: Drive Select byte for Drive and Head Register
76; CS:BP: Ptr to IDEVARS for the drive
77; DS: RAMVARS segment
78; ES: Zero (BDA segment)
79; Returns:
80; CF: Cleared if ATA-information read successfully
81; Set if any error
82; Corrupts registers:
83; AX, BL, CX, DX, SI, DI
84;--------------------------------------------------------------------
85.ReadAtaInfoFromHardDisk:
86 mov si, BOOTVARS.rgbAtaInfo ; ES:SI now points to ATA info location
87 push es
88 push si
89 push bx
90 call Device_IdentifyToBufferInESSIwithDriveSelectByteInBH
91 pop bx
92 pop si
93 pop es
94 jnc SHORT CreateBiosTablesForHardDisk
95 ; Fall to .ReadAtapiInfoFromDrive
96
97.ReadAtapiInfoFromDrive: ; Not yet implemented
98 ;call ReadAtapiInfoFromDrive ; Assume CD-ROM
99 ;jnc SHORT _CreateBiosTablesForCDROM
100 jmp DetectPrint_DriveNotFound
101
102
103;--------------------------------------------------------------------
104; CreateBiosTablesForHardDisk
105; Parameters:
106; BH: Drive Select byte for Drive and Head Register
107; CS:BP: Ptr to IDEVARS for the drive
108; ES:SI Ptr to ATA information for the drive
109; DS: RAMVARS segment
110; ES: BDA/Bootnfo segment
111; Returns:
112; Nothing
113; Corrupts registers:
114; AX, BX, CX, DX, SI, DI
115;--------------------------------------------------------------------
116CreateBiosTablesForHardDisk:
117 call CreateDPT_FromAtaInformation
118 jc SHORT .InvalidAtaInfo
119 call BootInfo_CreateForHardDisk
120 jmp DetectPrint_DriveNameFromBootnfoInESBX
121.InvalidAtaInfo:
122 jmp DetectPrint_DriveNotFound
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