source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AH24h_HSetBlocks.asm@ 612

Last change on this file since 612 was 588, checked in by krille_n_@…, 9 years ago

Changes:

  • Fixed a bug in AH24h_HSetBlocks.asm from r550. Trying to set a too large block size with an XT-CF card in DMA transfer mode would corrupt the stack.
  • Fixed a bug from r545 where the list of devices under g_szDeviceTypeValues in Strings.asm was no longer up to date causing the boot menu to display the wrong string for devices numbered higher than DEVICE_8BIT_XTCF_PIO8.
  • Made some fairly significant changes to the XT-CF code to reduce size. Two changes in functionality; 1) Added a simple check to validate the request for a change of the XT-CF transfer mode. 2) Changing transfer mode to use DMA no longer calls AH24h_SetBlockSize if the block size already is within the limits of DMA transfers. UNTESTED
  • XTIDECFG now clears IDEVARS.bIRQ when changing IDE controller to a serial device to keep the boot menu from displaying it since the serial device doesn't use IRQs at all.
  • Other minor optimizations.
File size: 3.8 KB
Line 
1; Project name : XTIDE Universal BIOS
2; Description : Int 13h function AH=24h, Set Multiple Blocks.
3
4;
5; XTIDE Universal BIOS and Associated Tools
6; Copyright (C) 2009-2010 by Tomi Tilli, 2011-2013 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; Int 13h function AH=24h, Set Multiple Blocks.
25;
26; AH24h_HandlerForSetMultipleBlocks
27; Parameters:
28; AL: Same as in INTPACK
29; DL: Translated Drive number
30; DS:DI: Ptr to DPT (in RAMVARS segment)
31; SS:BP: Ptr to IDEPACK
32; Parameters on INTPACK:
33; AL: Number of Sectors per Block (1, 2, 4, 8, 16, 32, 64 or 128)
34; Returns with INTPACK:
35; AH: Int 13h return status
36; CF: 0 if successful, 1 if error
37;--------------------------------------------------------------------
38AH24h_HandlerForSetMultipleBlocks:
39%ifndef USE_186
40 call AH24h_SetBlockSize
41 jmp Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
42%else
43 push Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
44 ; Fall to AH24h_SetBlockSize
45%endif
46
47
48;--------------------------------------------------------------------
49; AH24h_SetBlockSize
50; Parameters:
51; AL: Number of Sectors per Block (1, 2, 4, 8, 16, 32, 64 or 128)
52; DS:DI: Ptr to DPT (in RAMVARS segment)
53; SS:BP: Ptr to IDEPACK
54; Returns:
55; AH: Int 13h return status
56; CF: 0 if successful, 1 if error
57; Corrupts registers:
58; AL, CX, DX
59;--------------------------------------------------------------------
60AH24h_SetBlockSize:
61%ifdef MODULE_8BIT_IDE_ADVANCED
62 ; XT-CF does not support largest block size in DMA mode.
63 cmp al, XTCF_DMA_MODE_MAX_BLOCK_SIZE
64 jbe SHORT .NoNeedToLimitBlockSize
65
66 ; Return error if we tried too large block for XT-CF.
67 ; Do not limit it to maximum supported since software calling AH=24h
68 ; must know what the actual block size is.
69 cmp BYTE [di+DPT_ATA.bDevice], DEVICE_8BIT_XTCF_DMA
70 je SHORT ProcessXTCFsubcommandFromAL.AH1Eh_LoadInvalidCommandToAHandSetCF
71.NoNeedToLimitBlockSize:
72%endif ; MODULE_8BIT_IDE_ADVANCED
73
74 push bx
75
76 push ax ; Store block size for later use
77 xchg dx, ax ; DL = Block size (Sector Count Register)
78 mov al, COMMAND_SET_MULTIPLE_MODE
79 mov bx, TIMEOUT_AND_STATUS_TO_WAIT(TIMEOUT_DRDY, FLG_STATUS_DRDY)
80 call Idepack_StoreNonExtParametersAndIssueCommandFromAL
81
82 ; Disable block mode if failure or if called with block size of 1 sector.
83 ; Some drives allow block mode commands for 1 sector blocks and some do not.
84 pop bx ; Pop block size to BL
85 jc SHORT .DisableBlockMode
86
87 ; All valid block sizes are powers of 2 which means BL have just one bit set (parity odd).
88 ; Incrementing BX will cause all block sizes except 1 to have two bits set (parity even).
89 ; Note that PF reflects only the lowest 8 bits of any register being modified.
90 inc bx ; 1 -> 2 ?
91 jpo SHORT .DisableBlockMode ; Jump if BL = 2
92 dec bx ; Restore block size (was larger than 1)
93
94 ; Enable block mode and store block size
95 or BYTE [di+DPT.bFlagsHigh], FLGH_DPT_USE_BLOCK_MODE_COMMANDS
96 jmp SHORT .StoreBlockSizeFromBLandReturn
97
98.DisableBlockMode:
99 and BYTE [di+DPT.bFlagsHigh], ~FLGH_DPT_USE_BLOCK_MODE_COMMANDS
100 mov bl, 1
101 stc
102.StoreBlockSizeFromBLandReturn:
103 mov [di+DPT_ATA.bBlockSize], bl
104 pop bx
105 ret
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