Context Navigation

source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/CreateDPT.asm@ 412

Visit:

Last change on this file since 412 was 411, checked in by aitotat@…, 13 years ago

Changes to XTIDE Universal BIOS:

Moved some IRQ and LBA48 code to related modules.

File size: 10.8 KB

Rev	Line
[99]	1	; Project name : XTIDE Universal BIOS
[3]	2	; Description : Functions for creating Disk Parameter Table.
	3
[376]	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
[3]	20	; Section containing code
	21	SECTION .text
	22
	23	;--------------------------------------------------------------------
	24	; Creates new Disk Parameter Table for detected hard disk.
	25	; Drive is then fully accessible using any BIOS function.
	26	;
	27	; CreateDPT_FromAtaInformation
	28	; Parameters:
	29	; BH: Drive Select byte for Drive and Head Register
	30	; ES:SI: Ptr to 512-byte ATA information read from the drive
	31	; CS:BP: Ptr to IDEVARS for the controller
	32	; DS: RAMVARS segment
	33	; ES: BDA Segment
	34	; Returns:
	35	; DL: Drive number for new drive
[294]	36	; DS:DI: Ptr to Disk Parameter Table (if successful)
[3]	37	; CF: Cleared if DPT created successfully
	38	; Set if any error
	39	; Corrupts registers:
[99]	40	; AX, BX, CX, DH
[3]	41	;--------------------------------------------------------------------
	42	CreateDPT_FromAtaInformation:
[150]	43	call FindDPT_ForNewDriveToDSDI
[99]	44	; Fall to .InitializeDPT
[3]	45
	46	;--------------------------------------------------------------------
[99]	47	; .InitializeDPT
[3]	48	; Parameters:
	49	; BH: Drive Select byte for Drive and Head Register
	50	; DS:DI: Ptr to Disk Parameter Table
	51	; CS:BP: Ptr to IDEVARS for the controller
	52	; Returns:
[150]	53	; Nothing
[3]	54	; Corrupts registers:
[150]	55	; AX
[3]	56	;--------------------------------------------------------------------
[99]	57	.InitializeDPT:
[150]	58	mov [di+DPT.bIdevarsOffset], bp ; IDEVARS must start in first 256 bytes of ROM
	59	; Fall to .StoreDriveSelectAndDriveControlByte
[3]	60
	61	;--------------------------------------------------------------------
[150]	62	; .StoreDriveSelectAndDriveControlByte
[3]	63	; Parameters:
	64	; BH: Drive Select byte for Drive and Head Register
	65	; DS:DI: Ptr to Disk Parameter Table
	66	; ES:SI: Ptr to 512-byte ATA information read from the drive
	67	; CS:BP: Ptr to IDEVARS for the controller
	68	; Returns:
[99]	69	; Nothing
[3]	70	; Corrupts registers:
	71	; AX
	72	;--------------------------------------------------------------------
[150]	73	.StoreDriveSelectAndDriveControlByte:
	74	mov al, bh
	75	and ax, BYTE FLG_DRVNHEAD_DRV ; AL now has Master/Slave bit
[411]	76	%ifdef MODULE_IRQ
[150]	77	cmp [cs:bp+IDEVARS.bIRQ], ah ; Interrupts enabled?
	78	jz SHORT .StoreFlags ; If not, do not set interrupt flag
[158]	79	or al, FLGL_DPT_ENABLE_IRQ
[150]	80	.StoreFlags:
[411]	81	%endif
[150]	82	mov [di+DPT.wFlags], ax
[173]	83	; Fall to .StoreAddressing
[3]	84
	85	;--------------------------------------------------------------------
[173]	86	; .StoreAddressing
[3]	87	; Parameters:
	88	; DS:DI: Ptr to Disk Parameter Table
	89	; ES:SI: Ptr to 512-byte ATA information read from the drive
	90	; CS:BP: Ptr to IDEVARS for the controller
	91	; Returns:
[227]	92	; Nothing
[3]	93	; Corrupts registers:
[227]	94	; AX, BX, CX, DX
[3]	95	;--------------------------------------------------------------------
[173]	96	.StoreAddressing:
	97	; Check if CHS defined in ROMVARS
[193]	98	call AccessDPT_GetPointerToDRVPARAMStoCSBX
	99	test byte [cs:bx+DRVPARAMS.wFlags], FLG_DRVPARAMS_USERCHS ; User specified CHS?
[227]	100	jnz SHORT .StoreUserDefinedPCHS
[173]	101
	102	; Check if LBA supported
[169]	103	call AtaID_GetPCHStoAXBLBHfromAtaInfoInESSI
[173]	104	test BYTE [es:si+ATA1.wCaps+1], A1_wCaps_LBA>>8
[227]	105	jz SHORT .StoreCHSfromAXBHBL ; Small old drive with CHS addressing only
[3]	106
[324]	107	; Store LBA 28/48 addressing and total sector count
[173]	108	call AtaID_GetTotalSectorCountToBXDXAXfromAtaInfoInESSI
[324]	109	call StoreLbaAddressingAndTotalSectorCountFromBXDXAX
	110
	111	; Replace sector count with user defined if necessary
	112	call AccessDPT_GetPointerToDRVPARAMStoCSBX
	113	test BYTE [cs:bx+DRVPARAMS.wFlags], FLG_DRVPARAMS_USERLBA
	114	jz SHORT .KeepTotalSectorsFromAtaID
	115	mov ax, [cs:bx+DRVPARAMS.dwMaximumLBA]
	116	mov dx, [cs:bx+DRVPARAMS.dwMaximumLBA+2]
	117	xor bx, bx
	118
	119	; Compare user defined and ATA-ID sector count and select smaller
	120	cmp bx, [di+DPT.twLbaSectors+4]
	121	jb SHORT .StoreUserDefinedSectorCountToDPT
	122	cmp dx, [di+DPT.twLbaSectors+2]
	123	jb SHORT .StoreUserDefinedSectorCountToDPT
	124	ja SHORT .KeepTotalSectorsFromAtaID
	125	cmp ax, [di+DPT.twLbaSectors]
	126	jae SHORT .KeepTotalSectorsFromAtaID
	127	.StoreUserDefinedSectorCountToDPT:
	128	call StoreLbaAddressingAndTotalSectorCountFromBXDXAX
	129
	130	; Calculate L-CHS for old INT 13h
	131	.KeepTotalSectorsFromAtaID:
	132	mov bx, [di+DPT.twLbaSectors+4] ; Restore BX
[358]	133	call LbaAssist_ConvertSectorCountFromBXDXAXtoLbaAssistedCHSinDXAXBLBH
[227]	134	mov [di+DPT.bLbaHeads], bl
	135	jmp SHORT .StoreBlockMode
[173]	136
[227]	137	;--------------------------------------------------------------------
	138	; .StoreUserDefinedPCHS
	139	; Parameters:
	140	; DS:DI: Ptr to Disk Parameter Table
	141	; ES:SI: Ptr to 512-byte ATA information read from the drive
	142	; CS:BP: Ptr to IDEVARS for the controller
	143	; Returns:
	144	; AX: Number of P-CHS cylinders
	145	; BH: Number of P-CHS sectors per track
	146	; BL: Number of P-CHS heads
	147	; Corrupts registers:
	148	; Nothing
	149	;--------------------------------------------------------------------
	150	.StoreUserDefinedPCHS:
[3]	151	call AccessDPT_GetPointerToDRVPARAMStoCSBX
	152	mov ax, [cs:bx+DRVPARAMS.wCylinders]
[99]	153	mov bx, [cs:bx+DRVPARAMS.wHeadsAndSectors]
[227]	154	; Fall to .StoreCHSfromAXBHBL
[3]	155
[227]	156	;--------------------------------------------------------------------
	157	; .StoreCHSfromAXBHBL
	158	; Parameters:
	159	; AX: Number of P-CHS cylinders
	160	; BH: Number of P-CHS sectors per track
	161	; BL: Number of P-CHS heads
	162	; DS:DI: Ptr to Disk Parameter Table
	163	; ES:SI: Ptr to 512-byte ATA information read from the drive
	164	; CS:BP: Ptr to IDEVARS for the controller
	165	; Returns:
	166	; AX: Number of P-CHS cylinders
	167	; BH: Number of P-CHS sectors per track
	168	; BL: Number of P-CHS heads
	169	; Corrupts registers:
	170	; CX
	171	;--------------------------------------------------------------------
	172	.StoreCHSfromAXBHBL:
[173]	173	push ax
[227]	174	push bx
	175	call AccessDPT_ShiftPCHinAXBLtoLCH ; Get number of bits to shift
	176	pop bx
[173]	177	pop ax
[227]	178	jcxz .StorePCHSfromAXDX ; Small drive so use L-CHS addressing
[3]	179
[227]	180	; Store P-CHS addressing mode and number of bits to shift in L-CHS to P-CHS translation
	181	or cl, ADDRESSING_MODE_PCHS<<ADDRESSING_MODE_FIELD_POSITION
	182	or [di+DPT.bFlagsLow], cl
	183	; Fall to .StoreChsFromAXBLBH
	184
[3]	185	;--------------------------------------------------------------------
[227]	186	; .StoreChsFromAXBLBH
[3]	187	; Parameters:
[227]	188	; AX: Number of P-CHS cylinders
	189	; BH: Number of P-CHS sectors per track
	190	; BL: Number of P-CHS heads
[3]	191	; DS:DI: Ptr to Disk Parameter Table
	192	; ES:SI: Ptr to 512-byte ATA information read from the drive
[160]	193	; CS:BP: Ptr to IDEVARS for the controller
[3]	194	; Returns:
[99]	195	; Nothing
[3]	196	; Corrupts registers:
[227]	197	; Nothing
[3]	198	;--------------------------------------------------------------------
[227]	199	.StorePCHSfromAXDX:
	200	mov [di+DPT.wPchsCylinders], ax
	201	mov [di+DPT.wPchsHeadsAndSectors], bx
[99]	202	; Fall to .StoreBlockMode
[3]	203
	204	;--------------------------------------------------------------------
[99]	205	; .StoreBlockMode
[3]	206	; Parameters:
	207	; DS:DI: Ptr to Disk Parameter Table
	208	; ES:SI: Ptr to 512-byte ATA information read from the drive
[160]	209	; CS:BP: Ptr to IDEVARS for the controller
[3]	210	; Returns:
[99]	211	; Nothing
[3]	212	; Corrupts registers:
[150]	213	; Nothing
[3]	214	;--------------------------------------------------------------------
[99]	215	.StoreBlockMode:
[150]	216	cmp BYTE [es:si+ATA1.bBlckSize], 1 ; Max block size in sectors
	217	jbe SHORT .BlockModeTransfersNotSupported
[158]	218	or BYTE [di+DPT.bFlagsHigh], FLGH_DPT_BLOCK_MODE_SUPPORTED
[150]	219	.BlockModeTransfersNotSupported:
	220	; Fall to .StoreDeviceSpecificParameters
[3]	221
	222	;--------------------------------------------------------------------
[150]	223	; .StoreDeviceSpecificParameters
[3]	224	; Parameters:
	225	; DS:DI: Ptr to Disk Parameter Table
	226	; ES:SI: Ptr to 512-byte ATA information read from the drive
[160]	227	; CS:BP: Ptr to IDEVARS for the controller
[3]	228	; Returns:
[99]	229	; Nothing
[3]	230	; Corrupts registers:
[150]	231	; AX, BX, CX, DX
[3]	232	;--------------------------------------------------------------------
[150]	233	.StoreDeviceSpecificParameters:
	234	call Device_FinalizeDPT
[258]	235
[262]	236	;----------------------------------------------------------------------
	237	; Update drive counts (hard and floppy)
[294]	238	;----------------------------------------------------------------------
	239
[258]	240	%ifdef MODULE_SERIAL_FLOPPY
	241	;
	242	; These two instructions serve two purposes:
	243	; 1. If the drive is a floppy drive (CF set), then we effectively increment the counter.
[294]	244	; 2. If this is a hard disk, and there have been any floppy drives previously added, then the hard disk is
[258]	245	; effectively discarded. This is more of a safety check then code that should ever normally be hit (see below).
[294]	246	; Since the floppy DPT's come after the hard disk DPT's, without expensive (code size) code to relocate a DPT,
[258]	247	; this was necessary. Now, this situation shouldn't happen in normal operation, for a couple of reasons:
[294]	248	; A. xtidecfg always puts configured serial ports at the end of the IDEVARS list
[258]	249	; B. the auto serial code is always executed last
	250	; C. the serial server always returns floppy drives last
	251	;
	252	adc byte [RAMVARS.xlateVars+XLATEVARS.bFlopCreateCnt], 0
[294]	253	jnz .AllDone
[258]	254	%else
	255	;
	256	; Even without floppy support enabled, we shouldn't try to mount a floppy image as a hard disk, which
[294]	257	; could lead to unpredictable results since no MBR will be present, etc. The server doesn't know that
[258]	258	; floppies are supported, so it is important to still fail here if a floppy is seen during the drive scan.
	259	;
	260	jc .AllDone
	261	%endif
	262
[150]	263	inc BYTE [RAMVARS.bDrvCnt] ; Increment drive count to RAMVARS
[294]	264
	265	.AllDone:
[162]	266	clc
[3]	267	ret
[258]	268
[324]	269
	270	;--------------------------------------------------------------------
	271	; StoreLbaAddressingAndTotalSectorCountFromBXDXAX
	272	; Parameters:
	273	; BX:DX:AX: Total Sector Count
	274	; DS:DI: Ptr to Disk Parameter Table
	275	; Returns:
	276	; Nothing
	277	; Corrupts registers:
	278	; CX
	279	;--------------------------------------------------------------------
	280	StoreLbaAddressingAndTotalSectorCountFromBXDXAX:
	281	mov [di+DPT.twLbaSectors], ax
	282	mov [di+DPT.twLbaSectors+2], dx
	283	mov [di+DPT.twLbaSectors+4], bx
	284
[411]	285	%ifdef MODULE_EBIOS
[324]	286	and BYTE [di+DPT.bFlagsLow], ~MASKL_DPT_ADDRESSING_MODE
	287	test bx, bx
[346]	288	jnz SHORT .SetLba48AddressingToDPT ; Must be LBA48
	289
	290	; Drives can report at most 0FFF FFFFh LBA28 sectors according to ATA specification.
	291	; That is (2^28)-1 so we can simply check if DH is zero or not.
	292	test dh, dh
[324]	293	jz SHORT .SetLba28AddressingToDPT
	294	.SetLba48AddressingToDPT:
	295	or BYTE [di+DPT.bFlagsLow], ADDRESSING_MODE_LBA48<<ADDRESSING_MODE_FIELD_POSITION
	296	.SetLba28AddressingToDPT:
[411]	297	%endif
[324]	298	or BYTE [di+DPT.bFlagsLow], ADDRESSING_MODE_LBA28<<ADDRESSING_MODE_FIELD_POSITION
	299	ret

Note: See TracBrowser for help on using the repository browser.

Download in other formats: