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source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/CreateDPT.asm@ 380

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Last change on this file since 380 was 376, checked in by gregli@…, 12 years ago
WIDE checkin... Added copyright and license information to sorce files, as per the GPL instructions for usage.
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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
	76	cmp [cs:bp+IDEVARS.bIRQ], ah ; Interrupts enabled?
	77	jz SHORT .StoreFlags ; If not, do not set interrupt flag
[158]	78	or al, FLGL_DPT_ENABLE_IRQ
[150]	79	.StoreFlags:
	80	mov [di+DPT.wFlags], ax
[173]	81	; Fall to .StoreAddressing
[3]	82
	83	;--------------------------------------------------------------------
[173]	84	; .StoreAddressing
[3]	85	; Parameters:
	86	; DS:DI: Ptr to Disk Parameter Table
	87	; ES:SI: Ptr to 512-byte ATA information read from the drive
	88	; CS:BP: Ptr to IDEVARS for the controller
	89	; Returns:
[227]	90	; Nothing
[3]	91	; Corrupts registers:
[227]	92	; AX, BX, CX, DX
[3]	93	;--------------------------------------------------------------------
[173]	94	.StoreAddressing:
	95	; Check if CHS defined in ROMVARS
[193]	96	call AccessDPT_GetPointerToDRVPARAMStoCSBX
	97	test byte [cs:bx+DRVPARAMS.wFlags], FLG_DRVPARAMS_USERCHS ; User specified CHS?
[227]	98	jnz SHORT .StoreUserDefinedPCHS
[173]	99
	100	; Check if LBA supported
[169]	101	call AtaID_GetPCHStoAXBLBHfromAtaInfoInESSI
[173]	102	test BYTE [es:si+ATA1.wCaps+1], A1_wCaps_LBA>>8
[227]	103	jz SHORT .StoreCHSfromAXBHBL ; Small old drive with CHS addressing only
[3]	104
[324]	105	; Store LBA 28/48 addressing and total sector count
[173]	106	call AtaID_GetTotalSectorCountToBXDXAXfromAtaInfoInESSI
[324]	107	call StoreLbaAddressingAndTotalSectorCountFromBXDXAX
	108
	109	; Replace sector count with user defined if necessary
	110	call AccessDPT_GetPointerToDRVPARAMStoCSBX
	111	test BYTE [cs:bx+DRVPARAMS.wFlags], FLG_DRVPARAMS_USERLBA
	112	jz SHORT .KeepTotalSectorsFromAtaID
	113	mov ax, [cs:bx+DRVPARAMS.dwMaximumLBA]
	114	mov dx, [cs:bx+DRVPARAMS.dwMaximumLBA+2]
	115	xor bx, bx
	116
	117	; Compare user defined and ATA-ID sector count and select smaller
	118	cmp bx, [di+DPT.twLbaSectors+4]
	119	jb SHORT .StoreUserDefinedSectorCountToDPT
	120	cmp dx, [di+DPT.twLbaSectors+2]
	121	jb SHORT .StoreUserDefinedSectorCountToDPT
	122	ja SHORT .KeepTotalSectorsFromAtaID
	123	cmp ax, [di+DPT.twLbaSectors]
	124	jae SHORT .KeepTotalSectorsFromAtaID
	125	.StoreUserDefinedSectorCountToDPT:
	126	call StoreLbaAddressingAndTotalSectorCountFromBXDXAX
	127
	128	; Calculate L-CHS for old INT 13h
	129	.KeepTotalSectorsFromAtaID:
	130	mov bx, [di+DPT.twLbaSectors+4] ; Restore BX
[358]	131	call LbaAssist_ConvertSectorCountFromBXDXAXtoLbaAssistedCHSinDXAXBLBH
[227]	132	mov [di+DPT.bLbaHeads], bl
	133	jmp SHORT .StoreBlockMode
[173]	134
[227]	135	;--------------------------------------------------------------------
	136	; .StoreUserDefinedPCHS
	137	; Parameters:
	138	; DS:DI: Ptr to Disk Parameter Table
	139	; ES:SI: Ptr to 512-byte ATA information read from the drive
	140	; CS:BP: Ptr to IDEVARS for the controller
	141	; Returns:
	142	; AX: Number of P-CHS cylinders
	143	; BH: Number of P-CHS sectors per track
	144	; BL: Number of P-CHS heads
	145	; Corrupts registers:
	146	; Nothing
	147	;--------------------------------------------------------------------
	148	.StoreUserDefinedPCHS:
[3]	149	call AccessDPT_GetPointerToDRVPARAMStoCSBX
	150	mov ax, [cs:bx+DRVPARAMS.wCylinders]
[99]	151	mov bx, [cs:bx+DRVPARAMS.wHeadsAndSectors]
[227]	152	; Fall to .StoreCHSfromAXBHBL
[3]	153
[227]	154	;--------------------------------------------------------------------
	155	; .StoreCHSfromAXBHBL
	156	; Parameters:
	157	; AX: Number of P-CHS cylinders
	158	; BH: Number of P-CHS sectors per track
	159	; BL: Number of P-CHS heads
	160	; DS:DI: Ptr to Disk Parameter Table
	161	; ES:SI: Ptr to 512-byte ATA information read from the drive
	162	; CS:BP: Ptr to IDEVARS for the controller
	163	; Returns:
	164	; AX: Number of P-CHS cylinders
	165	; BH: Number of P-CHS sectors per track
	166	; BL: Number of P-CHS heads
	167	; Corrupts registers:
	168	; CX
	169	;--------------------------------------------------------------------
	170	.StoreCHSfromAXBHBL:
[173]	171	push ax
[227]	172	push bx
	173	call AccessDPT_ShiftPCHinAXBLtoLCH ; Get number of bits to shift
	174	pop bx
[173]	175	pop ax
[227]	176	jcxz .StorePCHSfromAXDX ; Small drive so use L-CHS addressing
[3]	177
[227]	178	; Store P-CHS addressing mode and number of bits to shift in L-CHS to P-CHS translation
	179	or cl, ADDRESSING_MODE_PCHS<<ADDRESSING_MODE_FIELD_POSITION
	180	or [di+DPT.bFlagsLow], cl
	181	; Fall to .StoreChsFromAXBLBH
	182
[3]	183	;--------------------------------------------------------------------
[227]	184	; .StoreChsFromAXBLBH
[3]	185	; Parameters:
[227]	186	; AX: Number of P-CHS cylinders
	187	; BH: Number of P-CHS sectors per track
	188	; BL: Number of P-CHS heads
[3]	189	; DS:DI: Ptr to Disk Parameter Table
	190	; ES:SI: Ptr to 512-byte ATA information read from the drive
[160]	191	; CS:BP: Ptr to IDEVARS for the controller
[3]	192	; Returns:
[99]	193	; Nothing
[3]	194	; Corrupts registers:
[227]	195	; Nothing
[3]	196	;--------------------------------------------------------------------
[227]	197	.StorePCHSfromAXDX:
	198	mov [di+DPT.wPchsCylinders], ax
	199	mov [di+DPT.wPchsHeadsAndSectors], bx
[99]	200	; Fall to .StoreBlockMode
[3]	201
	202	;--------------------------------------------------------------------
[99]	203	; .StoreBlockMode
[3]	204	; Parameters:
	205	; DS:DI: Ptr to Disk Parameter Table
	206	; ES:SI: Ptr to 512-byte ATA information read from the drive
[160]	207	; CS:BP: Ptr to IDEVARS for the controller
[3]	208	; Returns:
[99]	209	; Nothing
[3]	210	; Corrupts registers:
[150]	211	; Nothing
[3]	212	;--------------------------------------------------------------------
[99]	213	.StoreBlockMode:
[150]	214	cmp BYTE [es:si+ATA1.bBlckSize], 1 ; Max block size in sectors
	215	jbe SHORT .BlockModeTransfersNotSupported
[158]	216	or BYTE [di+DPT.bFlagsHigh], FLGH_DPT_BLOCK_MODE_SUPPORTED
[150]	217	.BlockModeTransfersNotSupported:
	218	; Fall to .StoreDeviceSpecificParameters
[3]	219
	220	;--------------------------------------------------------------------
[150]	221	; .StoreDeviceSpecificParameters
[3]	222	; Parameters:
	223	; DS:DI: Ptr to Disk Parameter Table
	224	; ES:SI: Ptr to 512-byte ATA information read from the drive
[160]	225	; CS:BP: Ptr to IDEVARS for the controller
[3]	226	; Returns:
[99]	227	; Nothing
[3]	228	; Corrupts registers:
[150]	229	; AX, BX, CX, DX
[3]	230	;--------------------------------------------------------------------
[150]	231	.StoreDeviceSpecificParameters:
	232	call Device_FinalizeDPT
[258]	233
[262]	234	;----------------------------------------------------------------------
	235	; Update drive counts (hard and floppy)
[294]	236	;----------------------------------------------------------------------
	237
[258]	238	%ifdef MODULE_SERIAL_FLOPPY
	239	;
	240	; These two instructions serve two purposes:
	241	; 1. If the drive is a floppy drive (CF set), then we effectively increment the counter.
[294]	242	; 2. If this is a hard disk, and there have been any floppy drives previously added, then the hard disk is
[258]	243	; effectively discarded. This is more of a safety check then code that should ever normally be hit (see below).
[294]	244	; Since the floppy DPT's come after the hard disk DPT's, without expensive (code size) code to relocate a DPT,
[258]	245	; this was necessary. Now, this situation shouldn't happen in normal operation, for a couple of reasons:
[294]	246	; A. xtidecfg always puts configured serial ports at the end of the IDEVARS list
[258]	247	; B. the auto serial code is always executed last
	248	; C. the serial server always returns floppy drives last
	249	;
	250	adc byte [RAMVARS.xlateVars+XLATEVARS.bFlopCreateCnt], 0
[294]	251	jnz .AllDone
[258]	252	%else
	253	;
	254	; Even without floppy support enabled, we shouldn't try to mount a floppy image as a hard disk, which
[294]	255	; could lead to unpredictable results since no MBR will be present, etc. The server doesn't know that
[258]	256	; floppies are supported, so it is important to still fail here if a floppy is seen during the drive scan.
	257	;
	258	jc .AllDone
	259	%endif
	260
[150]	261	inc BYTE [RAMVARS.bDrvCnt] ; Increment drive count to RAMVARS
[294]	262
	263	.AllDone:
[162]	264	clc
[3]	265	ret
[258]	266
[324]	267
	268	;--------------------------------------------------------------------
	269	; StoreLbaAddressingAndTotalSectorCountFromBXDXAX
	270	; Parameters:
	271	; BX:DX:AX: Total Sector Count
	272	; DS:DI: Ptr to Disk Parameter Table
	273	; Returns:
	274	; Nothing
	275	; Corrupts registers:
	276	; CX
	277	;--------------------------------------------------------------------
	278	StoreLbaAddressingAndTotalSectorCountFromBXDXAX:
	279	mov [di+DPT.twLbaSectors], ax
	280	mov [di+DPT.twLbaSectors+2], dx
	281	mov [di+DPT.twLbaSectors+4], bx
	282
	283	and BYTE [di+DPT.bFlagsLow], ~MASKL_DPT_ADDRESSING_MODE
	284	test bx, bx
[346]	285	jnz SHORT .SetLba48AddressingToDPT ; Must be LBA48
	286
	287	; Drives can report at most 0FFF FFFFh LBA28 sectors according to ATA specification.
	288	; That is (2^28)-1 so we can simply check if DH is zero or not.
	289	test dh, dh
[324]	290	jz SHORT .SetLba28AddressingToDPT
	291	.SetLba48AddressingToDPT:
	292	or BYTE [di+DPT.bFlagsLow], ADDRESSING_MODE_LBA48<<ADDRESSING_MODE_FIELD_POSITION
	293	.SetLba28AddressingToDPT:
	294	or BYTE [di+DPT.bFlagsLow], ADDRESSING_MODE_LBA28<<ADDRESSING_MODE_FIELD_POSITION
	295	ret

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