source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/Common/HPIO.asm@ 96

Last change on this file since 96 was 86, checked in by krille_n_@…, 14 years ago

Size optimizations in various files in the XTIDE BIOS.
Also added a new include file for generic macros (macros.inc).
File size: 9.3 KB
Line 
1; Project name : IDE BIOS
2; Description : PIO transfer functions.
3
4; Structure containing variables for PIO transfer functions
5struc PIOVARS, -6
6 .fnXfer resb 2 ; Offset to transfer function
7 .wBlockSize resb 2 ; Block size in WORDs
8 .wWordsLeft resb 2 ; Number of WORDs left to transfer
9 ; (full sectors, can be partial block)
10endstruc
11
12
13; Section containing code
14SECTION .text
15
16;--------------------------------------------------------------------
17; Normalizes far pointer to that offset overflows won't happen
18; when transferring data using PIO.
19;
20; HPIO_NORMALIZE_PTR
21; Parameters:
22; %1:%2: Far pointer to normalize
23; %3: Scratch register
24; %4: Scratch register
25; Returns:
26; %1:%2: Normalized far pointer
27; Corrupts registers:
28; %3, %4
29;--------------------------------------------------------------------
30%macro HPIO_NORMALIZE_PTR 4
31 mov %4, %2 ; Copy offset to scratch reg
32 and %2, BYTE 0Fh ; Clear offset bits 15...4
33 eSHR_IM %4, 4 ; Divide offset by 16
34 mov %3, %1 ; Copy segment to scratch reg
35 add %3, %4 ; Add shifted offset to segment
36 mov %1, %3 ; Set normalized segment
37%endmacro
38
39
40;--------------------------------------------------------------------
41; Reads sectors from hard disk using PIO transfer mode.
42;
43; HPIO_ReadBlock
44; Parameters:
45; AL: Number of sectors to read (1...255)
46; ES:BX: Pointer to buffer to recieve data
47; DS:DI: Ptr to Disk Parameter Table
48; Returns:
49; AH: BIOS Error code
50; CF: 0 if transfer succesfull
51; 1 if any error
52; Corrupts registers:
53; AL, BX, CX, DX
54;--------------------------------------------------------------------
55ALIGN JUMP_ALIGN
56HPIO_ReadBlock:
57 push es
58
59 ; Create PIOVARS to stack
60 eENTER PIOVARS_size, 0
61
62 push si
63 mov si, g_rgfnPioRead ; Offset to read function lookup
64 call HPIO_InitializePIOVARS ; Store word count and block size
65 pop si
66
67 ; Start to read data
68 xchg bx, di ; DS:BX points DPT, ES:DI points buffer
69 mov dx, [RAMVARS.wIdeBase] ; Load IDE Base Port address
70 call HPIO_ReadFromDrive
71
72 ; Destroy stack frame
73 eLEAVE
74 mov di, bx ; Restore DI
75 pop es
76 ret
77
78
79;--------------------------------------------------------------------
80; Initializes PIOVARS members.
81;
82; HPIO_InitializePIOVARS
83; Parameters:
84; AL: Number of sectors to transfer (1...255)
85; SI: Offset to transfer function lookup table
86; DS:DI: Ptr to Disk Parameter Table
87; ES:BX: Ptr to source or destination data buffer
88; SS:BP: Ptr to PIOVARS
89; Returns:
90; ES:BX: Normalized pointer to data buffer
91; Corrupts registers:
92; AX, CX
93;--------------------------------------------------------------------
94ALIGN JUMP_ALIGN
95HPIO_InitializePIOVARS:
96 ; Store number of WORDs to transfer
97 mov ah, al ; Number of WORDs to transfer...
98 xor al, al ; ...to AX
99 mov [bp+PIOVARS.wWordsLeft], ax ; Store WORD count
100
101 ; Store block size in WORDs
102 mov ah, [di+DPT.bSetBlock] ; AX = block size in WORDs
103 mov [bp+PIOVARS.wBlockSize], ax ; Store block size
104
105 ; Get transfer function based on bus type
106 xchg ax, bx ; Backup BX
107 eMOVZX bx, BYTE [di+DPT.bIdeOff] ; CS:BX now points to IDEVARS
108 mov bl, BYTE [cs:bx+IDEVARS.bBusType] ; Load bus type to BX
109 mov bx, [cs:bx+si] ; Load offset to transfer function
110 mov [bp+PIOVARS.fnXfer], bx ; Store offset to transfer function
111 xchg bx, ax
112 ; Fall to HPIO_NormalizePtr
113
114;--------------------------------------------------------------------
115; Initializes PIOVARS members.
116;
117; HPIO_InitializePIOVARS
118; Parameters:
119; ES:BX: Ptr to source or destination data buffer
120; Returns:
121; ES:BX: Normalized pointer to data buffer
122; Corrupts registers:
123; AX, CX
124;--------------------------------------------------------------------
125;ALIGN JUMP_ALIGN
126HPIO_NormalizeDataPointer:
127 HPIO_NORMALIZE_PTR es, bx, ax, cx
128 ret
129
130
131;--------------------------------------------------------------------
132; Reads blocks using PIO transfers.
133;
134; HPIO_ReadFromDrive
135; Parameters:
136; DX: IDE Data port address
137; DS:BX: Ptr to DPT (in RAMVARS segment)
138; ES:DI: Normalized ptr to buffer to recieve data
139; SS:BP: Ptr to PIOVARS
140; Returns:
141; AH: BIOS Error code
142; CF: 0 if transfer succesfull
143; 1 if any error
144; Corrupts registers:
145; AL, CX, DX, DI
146;--------------------------------------------------------------------
147ALIGN JUMP_ALIGN
148HPIO_ReadFromDrive:
149 cld ; INS to increment DI
150ALIGN JUMP_ALIGN
151.BlockLoop:
152 call HStatus_WaitIrqOrDrq ; Wait until ready to transfer
153 jc SHORT HPIO_WriteToDrive.RetError ; Return if error (code in AH)
154 mov cx, [bp+PIOVARS.wBlockSize] ; Load block size
155 sub [bp+PIOVARS.wWordsLeft], cx ; Transferring last (possibly partial) block?
156 jbe SHORT .XferLastBlock ; If so, jump to transfer
157 call [bp+PIOVARS.fnXfer] ; Transfer full block
158 jmp SHORT .BlockLoop ; Loop while blocks left
159ALIGN JUMP_ALIGN
160.XferLastBlock:
161 add cx, [bp+PIOVARS.wWordsLeft] ; CX to partial block size
162 call [bp+PIOVARS.fnXfer] ; Transfer possibly partial block
163 jmp HStatus_WaitBsyDefTime ; Check for errors
164
165
166;--------------------------------------------------------------------
167; Writes sectors to hard disk using PIO transfer mode.
168;
169; HPIO_WriteBlock
170; Parameters:
171; AL: Number of sectors to write (1...255)
172; ES:BX: Pointer to buffer containing data
173; DS:DI: Ptr to Disk Parameter Table
174; Returns:
175; AH: BIOS Error code
176; CF: 0 if transfer successfull
177; 1 if any error
178; Corrupts registers:
179; AL, BX, CX, DX
180;--------------------------------------------------------------------
181ALIGN JUMP_ALIGN
182HPIO_WriteBlock:
183 push es
184 push si
185
186 ; Create PIOVARS to stack
187 eENTER PIOVARS_size, 0
188
189 mov si, g_rgfnPioWrite ; Offset to write function lookup
190 call HPIO_InitializePIOVARS ; Store word count and block size
191
192 ; Prepare pointers and start transfer
193 mov si, bx ; ES:SI now points source buffer
194 mov bx, di ; DS:BX now points DPT
195 call HPIO_WriteToDrive
196
197 ; Destroy stack frame
198 eLEAVE
199
200 pop si
201 pop es
202 ret
203
204
205;--------------------------------------------------------------------
206; Writes blocks using PIO transfers.
207;
208; HPIO_WriteToDrive
209; Parameters:
210; DS:BX: Ptr to DPT (in RAMVARS segment)
211; ES:SI: Normalized ptr to buffer containing data
212; SS:BP: Ptr to PIOVARS
213; Returns:
214; AH: BIOS Error code
215; CF: 0 if transfer succesfull
216; 1 if any error
217; Corrupts registers:
218; AL, CX, DX, SI
219;--------------------------------------------------------------------
220ALIGN JUMP_ALIGN
221HPIO_WriteToDrive:
222 cld ; OUTS to increment SI
223 call HStatus_WaitDrqDefTime ; Always poll DRQ for first block, get status reg to DX
224 jc SHORT .RetError ; Return if error (code in AH)
225 sub dx, BYTE REGR_IDE_ST ; DX to Data Port address
226ALIGN JUMP_ALIGN
227.BlockLoop:
228 mov cx, [bp+PIOVARS.wBlockSize] ; Load block size
229 sub [bp+PIOVARS.wWordsLeft], cx ; Transferring last (possibly partial) block?
230 jbe SHORT .XferLastBlock ; If so, jump to transfer
231 call [bp+PIOVARS.fnXfer] ; Transfer full block
232 call HStatus_WaitIrqOrDrq ; Wait until ready to transfer
233 jnc SHORT .BlockLoop ; If no error, loop while blocks left
234.RetError:
235 ret ; This ret is shared with HPIO_ReadFromDrive
236ALIGN JUMP_ALIGN
237.XferLastBlock:
238 add cx, [bp+PIOVARS.wWordsLeft] ; CX to partial block size
239 call [bp+PIOVARS.fnXfer] ; Transfer possibly partial block
240 jmp HStatus_WaitIrqOrRdy ; Check for errors
241
242
243;--------------------------------------------------------------------
244; Bus specific transfer functions and lookup table.
245;
246; HPIO_DualByteRead Dual port 8-bit XTIDE PIO read transfer
247; HPIO_WordRead Normal 16-bit IDE PIO read transfer
248; HPIO_DualByteWrite Dual port 8-bit XTIDE PIO write transfer
249; HPIO_WordWrite Normal 16-bit IDE PIO write transfer
250; Parameters:
251; CX: Block size in WORDs
252; DX: IDE Data port address
253; ES:DI: Normalized ptr to buffer to recieve data (read only)
254; ES:SI: Normalized ptr to buffer containing data (write only)
255; Returns:
256; Nothing
257; Corrupts registers:
258; AX, CX
259;--------------------------------------------------------------------
260ALIGN JUMP_ALIGN
261HPIO_DualByteRead:
262 eREP_DUAL_BYTE_PORT_INSW
263 ret
264ALIGN JUMP_ALIGN
265HPIO_WordRead:
266 rep
267 db 6Dh ; INSW
268 ret
269ALIGN JUMP_ALIGN
270HPIO_DWordRead:
271 shr cx, 1 ; WORD count to DWORD count
272 rep
273 db 66h ; Override operand size to 32-bit
274 db 6Dh ; INSW/INSD
275 ret
276ALIGN JUMP_ALIGN
277HPIO_SingleByteRead:
278 eREP_SINGLE_BYTE_PORT_INSW
279 ret
280
281ALIGN JUMP_ALIGN
282HPIO_DualByteWrite:
283 eREP_DUAL_BYTE_PORT_OUTSW
284 ret
285ALIGN JUMP_ALIGN
286HPIO_WordWrite:
287 eSEG es ; Source is ES segment
288 rep
289 db 6Fh ; OUTSW
290 ret
291ALIGN JUMP_ALIGN
292HPIO_DWordWrite:
293 shr cx, 1 ; WORD count to DWORD count
294 eSEG es ; Source is ES segment
295 rep
296 db 66h ; Override operand size to 32-bit
297 db 6Fh ; OUTSW/OUTSD
298 ret
299ALIGN JUMP_ALIGN
300HPIO_SingleByteWrite:
301 eREP_SINGLE_BYTE_PORT_OUTSW
302 ret
303
304ALIGN WORD_ALIGN
305g_rgfnPioRead:
306 dw HPIO_DualByteRead ; 8-bit dual port reads
307 dw HPIO_WordRead ; 16-bit reads
308 dw HPIO_DWordRead ; 32-bit reads
309 dw HPIO_SingleByteRead ; 8-bit single port reads
310g_rgfnPioWrite:
311 dw HPIO_DualByteWrite ; 8-bit dual port writes
312 dw HPIO_WordWrite ; 16-bit writes
313 dw HPIO_DWordWrite ; 32-bit writes
314 dw HPIO_SingleByteWrite ; 8-bit single port writes
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