source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/Tools/Prepare.asm@ 477

Last change on this file since 477 was 477, checked in by aitotat@…, 12 years ago

Changes to XTIDE Universal BIOS:

  • Added non-working DMA transfer code.
File size: 5.6 KB
Line 
1; Project name : XTIDE Universal BIOS
2; Description : Functions for preparing data buffer for transfer.
3
4;
5; XTIDE Universal BIOS and Associated Tools
6; Copyright (C) 2009-2010 by Tomi Tilli, 2011-2012 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; Prepare_ByLoadingDapToESSIandVerifyingForTransfer
25; Parameters:
26; SI: Offset to DAP
27; DS:DI: Ptr to DPT
28; SS:BP: Ptr to IDEPACK
29; Parameters on INTPACK:
30; DS:SI: Ptr to Disk Address Packet
31; Returns:
32; BX: Index to command lookup table
33; ES:SI: Ptr to Disk Address Packet (DAP)
34; Exits from INT 13h if invalid DAP
35; Corrupts registers:
36; AX, DX
37;--------------------------------------------------------------------
38%ifdef MODULE_EBIOS
39ALIGN JUMP_ALIGN
40Prepare_ByLoadingDapToESSIandVerifyingForTransfer:
41 ; Load pointer to DAP to ES:SI and make sure it is valid
42 mov es, [bp+IDEPACK.intpack+INTPACK.ds] ; ES:SI to point Disk Address Packet
43 cmp BYTE [es:si+DAP.bSize], MINIMUM_DAP_SIZE
44 jb SHORT InvalidDAP
45
46 ; Make sure that sector count is valid
47 mov ax, [es:si+DAP.wSectorCount]
48 test ax, ax
49 jz SHORT ZeroSectorsRequestedSoNoErrors
50 cmp ax, BYTE 127
51 ja SHORT InvalidNumberOfSectorsRequested
52
53 ; Get EBIOS command index to BX
54 ; LBA28 or LBA48 command
55 call Prepare_GetOldInt13hCommandIndexToBX
56 mov al, [di+DPT.bFlagsLow]
57 eSHL_IM al, 1 ; Set CF if LBA48 supported
58 adc bl, bh ; LBA48 EXT commands
59 ret
60%endif ; MODULE_EBIOS
61
62
63;--------------------------------------------------------------------
64; Prepare_GetOldInt13hCommandIndexToBX
65; Parameters:
66; DS:DI: Ptr to DPT
67; Returns:
68; BX: Index to command lookup table
69; Corrupts registers:
70; Nothing
71;--------------------------------------------------------------------
72ALIGN JUMP_ALIGN
73Prepare_GetOldInt13hCommandIndexToBX:
74 ; Block mode or single sector
75 mov bl, [di+DPT.bFlagsHigh]
76 and bx, BYTE FLGH_DPT_BLOCK_MODE_SUPPORTED ; Bit 1
77 ret
78
79
80;---------------------------------------------------------------------
81; Prepare_BufferToESSIforOldInt13hTransfer
82; Parameters:
83; AL: Number of sectors to transfer
84; DS:DI: Ptr to DPT (in RAMVARS segment)
85; SS:BP: Ptr to IDEPACK
86; Parameters on INTPACK:
87; ES:BX: Ptr to data buffer
88; Returns:
89; ES:SI: Ptr to normalized data buffer
90; Exits INT 13h if error
91; Corrupts registers:
92; BX
93;--------------------------------------------------------------------
94ALIGN JUMP_ALIGN
95Prepare_BufferToESSIforOldInt13hTransfer:
96 mov si, [bp+IDEPACK.intpack+INTPACK.bx] ; Load offset
97
98%ifdef MODULE_8BIT_IDE
99 cmp BYTE [di+DPT_ATA.bDevice], DEVICE_8BIT_XTCF_DMA
100 jne SHORT .NormalizeForSmallestPossibleOffset
101
102 ; DMA transfers do not need to normalize pointer
103 ; (it will be converted to physical address in IdeDmaTransfer.asm)
104 mov es, [bp+IDEPACK.intpack+INTPACK.es]
105 jmp SHORT Prepare_ByValidatingSectorsInALforOldInt13h
106%endif ; MODULE_8BIT_IDE
107
108 ; Normalize segment for 16b pages
109.NormalizeForSmallestPossibleOffset:
110 mov bx, si
111 eSHR_IM bx, 4 ; Divide offset by 16
112 add bx, [bp+IDEPACK.intpack+INTPACK.es]
113 mov es, bx ; Segment normalized
114 and si, BYTE 0Fh ; Offset normalized
115 ; Fall to Prepare_ByValidatingSectorsInALforOldInt13h
116
117
118;---------------------------------------------------------------------
119; Prepare_ByValidatingSectorsInALforOldInt13h
120; Parameters:
121; AL: Number of sectors to transfer
122; Returns:
123; Exits INT 13h if invalid number of sectors in AL
124; Corrupts registers:
125; Nothing
126;--------------------------------------------------------------------
127Prepare_ByValidatingSectorsInALforOldInt13h:
128 test al, al
129 js SHORT .CheckZeroOffsetFor128Sectors ; 128 or more
130 jz SHORT InvalidNumberOfSectorsRequested ; Zero not allowed for old INT 13h
131 ret ; Continue with transfer
132
133ALIGN JUMP_ALIGN
134.CheckZeroOffsetFor128Sectors:
135 cmp al, 128
136 ja SHORT InvalidNumberOfSectorsRequested
137 test si, si ; Offset must be zero to xfer 128 sectors
138 jnz SHORT CannotAlignPointerProperly
139 ret ; Continue with transfer
140
141InvalidDAP:
142InvalidNumberOfSectorsRequested:
143Prepare_ReturnFromInt13hWithInvalidFunctionError:
144 mov ah, RET_HD_INVALID
145 SKIP2B f
146CannotAlignPointerProperly:
147 mov ah, RET_HD_BOUNDARY
148ZeroSectorsRequestedSoNoErrors:
149 jmp Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
150
151
152
153; Command lookup tables
154g_rgbReadCommandLookup:
155 db COMMAND_READ_SECTORS ; 00b, CHS or LBA28 single sector
156 db COMMAND_READ_SECTORS_EXT ; 01b, LBA48 single sector
157 db COMMAND_READ_MULTIPLE ; 10b, CHS or LBA28 block mode
158%ifdef MODULE_EBIOS
159 db COMMAND_READ_MULTIPLE_EXT ; 11b, LBA48 block mode
160%endif
161
162g_rgbWriteCommandLookup:
163 db COMMAND_WRITE_SECTORS
164 db COMMAND_WRITE_SECTORS_EXT
165 db COMMAND_WRITE_MULTIPLE
166%ifdef MODULE_EBIOS
167 db COMMAND_WRITE_MULTIPLE_EXT
168%endif
169
170g_rgbVerifyCommandLookup:
171 db COMMAND_VERIFY_SECTORS
172 db COMMAND_VERIFY_SECTORS_EXT
173 db COMMAND_VERIFY_SECTORS
174%ifdef MODULE_EBIOS
175 db COMMAND_VERIFY_SECTORS_EXT
176%endif
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