1 | ; Project name : XTIDE Universal BIOS
|
---|
2 | ; Description : Serial Device Command functions.
|
---|
3 |
|
---|
4 | ; Section containing code
|
---|
5 | SECTION .text
|
---|
6 |
|
---|
7 | ;--------------- UART Equates -----------------------------
|
---|
8 | ;
|
---|
9 | ; Serial Programming References:
|
---|
10 | ; http://en.wikibooks.org/wiki/Serial_Programming
|
---|
11 | ;
|
---|
12 |
|
---|
13 | SerialCommand_UART_base EQU 0
|
---|
14 | SerialCommand_UART_transmitByte EQU 0
|
---|
15 | SerialCommand_UART_receiveByte EQU 0
|
---|
16 |
|
---|
17 | ;
|
---|
18 | ; Values for UART_divisorLow:
|
---|
19 | ; 60h = 1200, 30h = 2400, 18h = 4800, 0ch = 9600, 6 = 19200, 4 = 28800, 3 = 38400, 2 = 57600, 1 = 115200
|
---|
20 | ;
|
---|
21 | SerialCommand_UART_divisorLow EQU 0
|
---|
22 |
|
---|
23 | ;
|
---|
24 | ; UART_divisorHigh is zero for all speeds including and above 1200 baud (which is all we do)
|
---|
25 | ;
|
---|
26 | SerialCommand_UART_divisorHigh EQU 1
|
---|
27 |
|
---|
28 | SerialCommand_UART_interruptIdent EQU 2
|
---|
29 | SerialCommand_UART_FIFOControl EQU 2
|
---|
30 |
|
---|
31 | SerialCommand_UART_lineControl EQU 3
|
---|
32 |
|
---|
33 | SerialCommand_UART_modemControl EQU 4
|
---|
34 |
|
---|
35 | SerialCommand_UART_lineStatus EQU 5
|
---|
36 |
|
---|
37 | SerialCommand_UART_modemStatus EQU 6
|
---|
38 |
|
---|
39 | SerialCommand_UART_scratch EQU 7
|
---|
40 |
|
---|
41 | SerialCommand_Protocol_Write EQU 3
|
---|
42 | SerialCommand_Protocol_Read EQU 2
|
---|
43 | SerialCommand_Protocol_Inquire EQU 0
|
---|
44 | SerialCommand_Protocol_Header EQU 0a0h
|
---|
45 |
|
---|
46 | ;--------------------------------------------------------------------
|
---|
47 | ; SerialCommand_OutputWithParameters
|
---|
48 | ; Parameters:
|
---|
49 | ; BH: Non-zero if 48-bit addressing used
|
---|
50 | ; (ignored at present as 48-bit addressing is not supported)
|
---|
51 | ; BL: IDE Status Register bit to poll after command
|
---|
52 | ; (ignored at present, since there is no IDE status register to poll)
|
---|
53 | ; ES:SI: Ptr to buffer (for data transfer commands)
|
---|
54 | ; DS:DI: Ptr to DPT (in RAMVARS segment)
|
---|
55 | ; SS:BP: Ptr to IDEREGS_AND_INTPACK
|
---|
56 | ; Returns:
|
---|
57 | ; AH: INT 13h Error Code
|
---|
58 | ; CF: Cleared if success, Set if error
|
---|
59 | ; Corrupts registers:
|
---|
60 | ; AL, BX, CX, DX, (ES:SI for data transfer commands)
|
---|
61 | ;--------------------------------------------------------------------
|
---|
62 | ALIGN JUMP_ALIGN
|
---|
63 | SerialCommand_OutputWithParameters:
|
---|
64 |
|
---|
65 | mov ah,(SerialCommand_Protocol_Header | SerialCommand_Protocol_Read)
|
---|
66 |
|
---|
67 | mov al,[bp+IDEPACK.bCommand]
|
---|
68 |
|
---|
69 | cmp al,20h ; Read Sectors IDE command
|
---|
70 | jz .readOrWrite
|
---|
71 | inc ah ; now SerialCommand_Protocol_Write
|
---|
72 | cmp al,30h ; Write Sectors IDE command
|
---|
73 | jz .readOrWrite
|
---|
74 |
|
---|
75 | ; all other commands return success
|
---|
76 | ; including function 0ech which should return drive information, this is handled with the identify functions
|
---|
77 | ;
|
---|
78 | xor ah,ah ; also clears carry
|
---|
79 | ret
|
---|
80 |
|
---|
81 | .readOrWrite:
|
---|
82 | mov [bp+IDEPACK.bFeatures],ah ; store protocol command
|
---|
83 |
|
---|
84 | mov dx, [di+DPT_SERIAL.wSerialPortAndBaud]
|
---|
85 |
|
---|
86 | ; fall-through
|
---|
87 |
|
---|
88 | ;--------------------------------------------------------------------
|
---|
89 | ; SerialCommand_OutputWithParameters_DeviceInDX
|
---|
90 | ; Parameters:
|
---|
91 | ; AH: Protocol Command
|
---|
92 | ; DX: Packed I/O port and baud rate
|
---|
93 | ; ES:SI: Ptr to buffer (for data transfer commands)
|
---|
94 | ; SS:BP: Ptr to IDEREGS_AND_INTPACK
|
---|
95 | ; Returns:
|
---|
96 | ; AH: INT 13h Error Code
|
---|
97 | ; CF: Cleared if success, Set if error
|
---|
98 | ; Corrupts registers:
|
---|
99 | ; AL, BX, CX, DX, (ES:SI for data transfer commands)
|
---|
100 | ;--------------------------------------------------------------------
|
---|
101 | SerialCommand_OutputWithParameters_DeviceInDX:
|
---|
102 |
|
---|
103 | push si
|
---|
104 | push di
|
---|
105 | push bp
|
---|
106 |
|
---|
107 | ;
|
---|
108 | ; Unpack I/O port and baud from DPT
|
---|
109 | ; Port to DX for the remainder of the routine (+/- different register offsets)
|
---|
110 | ; Baud in CH until UART initialization is complete
|
---|
111 | ;
|
---|
112 | mov ch,dh
|
---|
113 | xor dh,dh
|
---|
114 | eSHL_IM dx, 2 ; shift from one byte to two
|
---|
115 |
|
---|
116 | mov al,[bp+IDEPACK.bSectorCount]
|
---|
117 |
|
---|
118 | ;
|
---|
119 | ; Command byte and sector count live at the top of the stack, pop/push are used to access
|
---|
120 | ;
|
---|
121 | push ax
|
---|
122 |
|
---|
123 | %if 0
|
---|
124 | cld ; Shouldn't be needed. DF has already been cleared (line 24, Int13h.asm)
|
---|
125 | %endif
|
---|
126 |
|
---|
127 | ;----------------------------------------------------------------------
|
---|
128 | ;
|
---|
129 | ; Initialize UART
|
---|
130 | ;
|
---|
131 | ; We do this each time since DOS (at boot) or another program may have
|
---|
132 | ; decided to reprogram the UART
|
---|
133 | ;
|
---|
134 | mov bl,dl ; setup BL with proper values for read/write loops (BH comes later)
|
---|
135 |
|
---|
136 | mov al,83h
|
---|
137 | add dl,SerialCommand_UART_lineControl
|
---|
138 | out dx,al
|
---|
139 |
|
---|
140 | mov al,ch
|
---|
141 | mov dl,bl ; divisor low
|
---|
142 | out dx,al
|
---|
143 |
|
---|
144 | xor ax,ax
|
---|
145 | inc dx ; divisor high
|
---|
146 | push dx
|
---|
147 | out dx,al
|
---|
148 |
|
---|
149 | mov al,047h
|
---|
150 | inc dx ; fifo
|
---|
151 | out dx,al
|
---|
152 |
|
---|
153 | mov al,03h
|
---|
154 | inc dx ; linecontrol
|
---|
155 | out dx,al
|
---|
156 |
|
---|
157 | mov al,0bh
|
---|
158 | inc dx ; modemcontrol
|
---|
159 | out dx,al
|
---|
160 |
|
---|
161 | inc dx ; linestatus (no output now, just setting up BH for later use)
|
---|
162 | mov bh,dl
|
---|
163 |
|
---|
164 | pop dx ; base, interrupts disabled
|
---|
165 | xor ax,ax
|
---|
166 | out dx,al
|
---|
167 |
|
---|
168 | ;----------------------------------------------------------------------
|
---|
169 | ;
|
---|
170 | ; Send Command
|
---|
171 | ;
|
---|
172 | ; Sends first six bytes of IDEREGS_AND_INTPACK as the command
|
---|
173 | ;
|
---|
174 | push es ; save off real buffer location
|
---|
175 | push si
|
---|
176 |
|
---|
177 | mov si,bp ; point to IDEREGS for command dispatch;
|
---|
178 | push ss
|
---|
179 | pop es
|
---|
180 |
|
---|
181 | mov di,0ffffh ; initialize checksum for write
|
---|
182 | mov bp,di
|
---|
183 |
|
---|
184 | mov cx,4 ; writing 3 words (plus 1)
|
---|
185 |
|
---|
186 | cli ; interrupts off...
|
---|
187 |
|
---|
188 | call SerialCommand_WriteProtocol.entry
|
---|
189 |
|
---|
190 | pop di ; restore real buffer location (note change from SI to DI)
|
---|
191 | ; Buffer is primarily referenced through ES:DI throughout, since
|
---|
192 | ; we need to store (read sector) faster than we read (write sector)
|
---|
193 | pop es
|
---|
194 |
|
---|
195 | %if 0
|
---|
196 | ;;; no longer needed, since the pointer is normalized before we are called and we do not support
|
---|
197 | ;;; more than 128 sectors (and for 128 specifically, the pointer must be segment aligned).
|
---|
198 | ;;; See comments below at the point this entry point was called for more details...
|
---|
199 | .nextSectorNormalize:
|
---|
200 | call Registers_NormalizeESDI
|
---|
201 | %endif
|
---|
202 |
|
---|
203 | pop ax ; load command byte (done before call to .nextSector on subsequent iterations)
|
---|
204 | push ax
|
---|
205 |
|
---|
206 | ;
|
---|
207 | ; Top of the read/write loop, one iteration per sector
|
---|
208 | ;
|
---|
209 | .nextSector:
|
---|
210 | mov si,0ffffh ; initialize checksum for read or write
|
---|
211 | mov bp,si
|
---|
212 |
|
---|
213 | mov cx,0101h ; writing 256 words (plus 1)
|
---|
214 |
|
---|
215 | shr ah,1 ; command byte, are we doing a write?
|
---|
216 | jnc .readEntry
|
---|
217 |
|
---|
218 | xchg si,di
|
---|
219 | call SerialCommand_WriteProtocol.entry
|
---|
220 | xchg si,di
|
---|
221 |
|
---|
222 | inc cx ; CX = 1 now (0 out of WriteProtocol)
|
---|
223 | jmp .readEntry
|
---|
224 |
|
---|
225 | ;----------------------------------------------------------------------
|
---|
226 | ;
|
---|
227 | ; Timeout
|
---|
228 | ;
|
---|
229 | ; To save code space, we use the contents of DL to decide which byte in the word to return for reading.
|
---|
230 | ;
|
---|
231 | .readTimeout:
|
---|
232 | push ax ; not only does this push preserve AX (which we need), but it also
|
---|
233 | ; means the stack has the same number of bytes on it as when we are
|
---|
234 | ; sending a packet, important for error cleanup and exit
|
---|
235 | mov ah,1
|
---|
236 | call SerialCommand_WaitAndPoll_Read
|
---|
237 | pop ax
|
---|
238 | test dl,1
|
---|
239 | jz .readByte1Ready
|
---|
240 | jmp .readByte2Ready
|
---|
241 |
|
---|
242 | ;----------------------------------------------------------------------------
|
---|
243 | ;
|
---|
244 | ; Read Block (without interrupts, used when there is a FIFO, high speed)
|
---|
245 | ;
|
---|
246 | ; NOTE: This loop is very time sensitive. Literally, another instruction
|
---|
247 | ; cannot be inserted into this loop without us falling behind at high
|
---|
248 | ; speed (460.8K baud) on a 4.77Mhz 8088, making it hard to receive
|
---|
249 | ; a full 512 byte block.
|
---|
250 | ;
|
---|
251 | .readLoop:
|
---|
252 | stosw ; store word in caller's data buffer
|
---|
253 |
|
---|
254 | add bp, ax ; update Fletcher's checksum
|
---|
255 | adc bp, 0
|
---|
256 | add si, bp
|
---|
257 | adc si, 0
|
---|
258 |
|
---|
259 | .readEntry:
|
---|
260 | mov dl,bh
|
---|
261 | in al,dx
|
---|
262 | shr al,1 ; data ready (byte 1)?
|
---|
263 | mov dl,bl ; get ready to read data
|
---|
264 | jnc .readTimeout ; nope not ready, update timeouts
|
---|
265 |
|
---|
266 | ;
|
---|
267 | ; Entry point after initial timeout. We enter here so that the checksum word
|
---|
268 | ; is not stored (and is left in AX after the loop is complete).
|
---|
269 | ;
|
---|
270 | .readByte1Ready:
|
---|
271 | in al, dx ; read data byte 1
|
---|
272 |
|
---|
273 | mov ah, al ; store byte in ah for now
|
---|
274 |
|
---|
275 | ;
|
---|
276 | ; note the placement of this reset of dl to bh, and that it is
|
---|
277 | ; before the return, which is assymetric with where this is done
|
---|
278 | ; above for byte 1. The value of dl is used by the timeout routine
|
---|
279 | ; to know which byte to return to (.read_byte1_ready or
|
---|
280 | ; .read_byte2_ready)
|
---|
281 | ;
|
---|
282 | mov dl,bh
|
---|
283 |
|
---|
284 | in al,dx
|
---|
285 | shr al,1 ; data ready (byte 2)?
|
---|
286 | jnc .readTimeout
|
---|
287 | .readByte2Ready:
|
---|
288 | mov dl,bl
|
---|
289 | in al, dx ; read data byte 2
|
---|
290 |
|
---|
291 | xchg al, ah ; ah was holding byte 1, reverse byte order
|
---|
292 |
|
---|
293 | loop .readLoop
|
---|
294 |
|
---|
295 | sti ; interrupts back on ASAP, between packets
|
---|
296 |
|
---|
297 | ;
|
---|
298 | ; Compare checksums
|
---|
299 | ;
|
---|
300 | xchg ax,bp
|
---|
301 | xor ah,al
|
---|
302 | mov cx,si
|
---|
303 | xor cl,ch
|
---|
304 | mov al,cl
|
---|
305 | cmp ax,bp
|
---|
306 | jnz SerialCommand_OutputWithParameters_Error
|
---|
307 |
|
---|
308 | pop ax ; sector count and command byte
|
---|
309 | dec al ; decrement sector count
|
---|
310 | push ax ; save
|
---|
311 | jz SerialCommand_OutputWithParameters_ReturnCodeInALCF ; CF=0 from "cmp ax,bp" returning Zero above
|
---|
312 |
|
---|
313 | cli ; interrupts back off for ACK byte to host
|
---|
314 | ; (host could start sending data immediately)
|
---|
315 | out dx,al ; ACK with next sector number
|
---|
316 |
|
---|
317 | %if 0
|
---|
318 | ;;; This code is no longer needed as we do not support more than 128 sectors, and for 128 the pointer
|
---|
319 | ;;; must be segment aligned. If we ever do want to support more sectors, the code can help...
|
---|
320 |
|
---|
321 | ;
|
---|
322 | ; Normalize buffer pointer for next go round, if needed.
|
---|
323 | ;
|
---|
324 | ; We need to re-normalize the pointer in ES:DI after processing every 7f sectors. That number could
|
---|
325 | ; have been 80 if we knew the offset was on a segment boundary, but this may not be the case.
|
---|
326 | ;
|
---|
327 | ; We re-normalize based on the sector count (flags from "dec al" above)...
|
---|
328 | ; a) we normalize before the first sector goes out, immediately after sending the command packet (above)
|
---|
329 | ; b) on transitions from FF to FE, very rare case for writing 255 or 256 sectors
|
---|
330 | ; c) on transitions from 80 to 7F, a large read/write
|
---|
331 | ; d) on transitions from 00 to FF, very, very rare case of writing 256 sectors
|
---|
332 | ; We don't need to renormalize in this case, but it isn't worth the memory/effort to not do
|
---|
333 | ; the extra work, and it does no harm.
|
---|
334 | ;
|
---|
335 | ; I really don't care much about (d) because I have not seen cases where any OS makes a request
|
---|
336 | ; for more than 127 sectors. Back in the day, it appears that some BIOS could not support more than 127
|
---|
337 | ; sectors, so that may be the practical limit for OS and application developers. The Extended BIOS
|
---|
338 | ; function also appear to be capped at 127 sectors. So although this can support the full 256 sectors
|
---|
339 | ; if needed, we are optimized for that 1-127 range.
|
---|
340 | ;
|
---|
341 | ; Assume we start with 0000:000f, with 256 sectors to write...
|
---|
342 | ; After first packet, 0000:020f
|
---|
343 | ; First decrement of AL, transition from 00 to FF: renormalize to 0020:000f (unnecessary)
|
---|
344 | ; After second packet, 0020:020f
|
---|
345 | ; Second derement of AL, transition from FF to FE: renormalize to 0040:000f
|
---|
346 | ; After 7f more packets, 0040:fe0f
|
---|
347 | ; Decrement of AL, transition from 80 to 7F: renormalize to 1020:000f
|
---|
348 | ; After 7f more packets, 1020:fe0f or 2000:000f if normalized
|
---|
349 | ; Decrement of AL, from 1 to 0: exit
|
---|
350 | ;
|
---|
351 | jge short .nextSector ; OF=SF, branch for 1-7e, most common case
|
---|
352 | ; (0 kicked out above for return success)
|
---|
353 |
|
---|
354 | add al,2 ; 7f-ff moves to 81-01
|
---|
355 | ; (0-7e kicked out before we get here)
|
---|
356 | ; 7f moves to 81 and OF=1, so OF=SF
|
---|
357 | ; fe moves to 0 and OF=0, SF=0, so OF=SF
|
---|
358 | ; ff moves to 1 and OF=0, SF=0, so OF=SF
|
---|
359 | ; 80-fd moves to 82-ff and OF=0, so OF<>SF
|
---|
360 |
|
---|
361 | jl short .nextSector ; OF<>SF, branch for all cases but 7f, fe, and ff
|
---|
362 |
|
---|
363 | ; jpo short .nextSector ; if we really wanted to avoid normalizing for ff, this
|
---|
364 | ; is one way to do it, but it adds more memory and more
|
---|
365 | ; cycles for the 7f and fe cases. IMHO, given that I've
|
---|
366 | ; never seen a request for more than 7f, this seems unnecessary.
|
---|
367 |
|
---|
368 | jmp short .nextSectorNormalize ; our two renormalization cases (plus one for ff)
|
---|
369 |
|
---|
370 | %else
|
---|
371 |
|
---|
372 | jmp short .nextSector
|
---|
373 |
|
---|
374 | %endif
|
---|
375 |
|
---|
376 | ;---------------------------------------------------------------------------
|
---|
377 | ;
|
---|
378 | ; Cleanup, error reporting, and exit
|
---|
379 | ;
|
---|
380 |
|
---|
381 | ;
|
---|
382 | ; Used in situations where a call is underway, such as with SerialCommand_WaitAndPoll
|
---|
383 | ;
|
---|
384 | ALIGN JUMP_ALIGN
|
---|
385 | SerialCommand_OutputWithParameters_ErrorAndPop4Words:
|
---|
386 | add sp,8
|
---|
387 | ;;; fall-through
|
---|
388 |
|
---|
389 | ALIGN JUMP_ALIGN
|
---|
390 | SerialCommand_OutputWithParameters_Error:
|
---|
391 | ;----------------------------------------------------------------------
|
---|
392 | ;
|
---|
393 | ; Clear read buffer
|
---|
394 | ;
|
---|
395 | ; In case there are extra characters or an error in the FIFO, clear it out.
|
---|
396 | ; In theory the initialization of the UART registers above should have
|
---|
397 | ; taken care of this, but I have seen cases where this is not true.
|
---|
398 | ;
|
---|
399 | xor cx,cx ; timeout this clearing routine, in case the UART isn't there
|
---|
400 | .clearBuffer:
|
---|
401 | mov dl,bh
|
---|
402 | in al,dx
|
---|
403 | mov dl,bl
|
---|
404 | test al,08fh
|
---|
405 | jz .clearBufferComplete
|
---|
406 | test al,1
|
---|
407 | in al,dx
|
---|
408 | loopnz .clearBuffer ; note ZF from test above
|
---|
409 |
|
---|
410 | .clearBufferComplete:
|
---|
411 | stc
|
---|
412 | mov al,1
|
---|
413 |
|
---|
414 | ALIGN JUMP_ALIGN
|
---|
415 | SerialCommand_OutputWithParameters_ReturnCodeInALCF:
|
---|
416 | %if 0
|
---|
417 | sti ; all paths here will already have interrupts turned back on
|
---|
418 | %endif
|
---|
419 | mov ah,al
|
---|
420 |
|
---|
421 | pop bp ; recover ax (command and count) from stack, throw away
|
---|
422 |
|
---|
423 | pop bp
|
---|
424 | pop di
|
---|
425 | pop si
|
---|
426 |
|
---|
427 | ret
|
---|
428 |
|
---|
429 | ;--------------------------------------------------------------------
|
---|
430 | ; SerialCommand_WriteProtocol
|
---|
431 | ;
|
---|
432 | ; NOTE: As with its read counterpart, this loop is very time sensitive.
|
---|
433 | ; Although it will still function, adding additional instructions will
|
---|
434 | ; impact the write throughput, especially on slower machines.
|
---|
435 | ;
|
---|
436 | ; Parameters:
|
---|
437 | ; ES:SI: Ptr to buffer
|
---|
438 | ; CX: Words to write, plus 1
|
---|
439 | ; BP/DI: Initialized for Checksum (-1 in each)
|
---|
440 | ; DH: I/O Port high byte
|
---|
441 | ; BX: LineStatus Register address (BH) and Receive/Transmit Register address (BL)
|
---|
442 | ; Returns:
|
---|
443 | ; BP/DI: Checksum for written bytes, compared against ACK from server in .readLoop
|
---|
444 | ; CX: Zero
|
---|
445 | ; DL: Receive/Transmit Register address
|
---|
446 | ; Corrupts registers:
|
---|
447 | ; AX
|
---|
448 | ;--------------------------------------------------------------------
|
---|
449 | ALIGN JUMP_ALIGN
|
---|
450 | SerialCommand_WriteProtocol:
|
---|
451 | .writeLoop:
|
---|
452 | es lodsw ; fetch next word
|
---|
453 |
|
---|
454 | out dx,al ; output first byte
|
---|
455 |
|
---|
456 | add bp,ax ; update checksum
|
---|
457 | adc bp,0
|
---|
458 | add di,bp
|
---|
459 | adc di,0
|
---|
460 |
|
---|
461 | mov dl,bh ; transmit buffer empty?
|
---|
462 | in al,dx
|
---|
463 | test al,20h
|
---|
464 | jz .writeTimeout2 ; nope, use our polling routine
|
---|
465 |
|
---|
466 | .writeByte2Ready:
|
---|
467 | mov dl,bl
|
---|
468 | mov al,ah ; output second byte
|
---|
469 | out dx,al
|
---|
470 |
|
---|
471 | .entry:
|
---|
472 | mov dl,bh ; transmit buffer empty?
|
---|
473 | in al,dx
|
---|
474 | test al,20h
|
---|
475 | mov dl,bl
|
---|
476 | jz .writeTimeout1 ; nope, use our polling routine
|
---|
477 |
|
---|
478 | .writeByte1Ready:
|
---|
479 | loop .writeLoop
|
---|
480 |
|
---|
481 | mov ax,di ; fold Fletcher's checksum and output
|
---|
482 | xor al,ah
|
---|
483 | out dx,al ; byte 1
|
---|
484 |
|
---|
485 | call SerialCommand_WaitAndPoll_Write
|
---|
486 |
|
---|
487 | mov ax,bp
|
---|
488 | xor al,ah
|
---|
489 | out dx,al ; byte 2
|
---|
490 |
|
---|
491 | ret
|
---|
492 |
|
---|
493 | .writeTimeout2:
|
---|
494 | mov dl,ah ; need to preserve AH, but don't need DL (will be reset upon return)
|
---|
495 | call SerialCommand_WaitAndPoll_Write
|
---|
496 | mov ah,dl
|
---|
497 | jmp .writeByte2Ready
|
---|
498 |
|
---|
499 | .writeTimeout1:
|
---|
500 | %ifndef USE_186
|
---|
501 | mov ax,.writeByte1Ready
|
---|
502 | push ax ; return address for ret at end of SC_writeTimeout2
|
---|
503 | %else
|
---|
504 | push .writeByte1Ready
|
---|
505 | %endif
|
---|
506 | ;;; fall-through
|
---|
507 |
|
---|
508 | ;--------------------------------------------------------------------
|
---|
509 | ; SerialCommand_WaitAndPoll
|
---|
510 | ;
|
---|
511 | ; Parameters:
|
---|
512 | ; AH: UART_LineStatus bit to test (20h for write, or 1h for read)
|
---|
513 | ; One entry point fills in AH with 20h for write
|
---|
514 | ; DX: Port address (OK if already incremented to UART_lineStatus)
|
---|
515 | ; BX:
|
---|
516 | ; Stack: 2 words on the stack below the command/count word
|
---|
517 | ; Returns:
|
---|
518 | ; Returns when desired UART_LineStatus bit is cleared
|
---|
519 | ; Jumps directly to error exit if timeout elapses (and cleans up stack)
|
---|
520 | ; Corrupts registers:
|
---|
521 | ; AX
|
---|
522 | ;--------------------------------------------------------------------
|
---|
523 |
|
---|
524 | SerialCommand_WaitAndPoll_SoftDelayTicks EQU 20
|
---|
525 |
|
---|
526 | ALIGN JUMP_ALIGN
|
---|
527 | SerialCommand_WaitAndPoll_Write:
|
---|
528 | mov ah,20h
|
---|
529 | ;;; fall-through
|
---|
530 |
|
---|
531 | ALIGN JUMP_ALIGN
|
---|
532 | SerialCommand_WaitAndPoll_Read:
|
---|
533 | push cx
|
---|
534 | push dx
|
---|
535 |
|
---|
536 | ;
|
---|
537 | ; We first poll in a tight loop, interrupts off, for the next character to come in/be sent
|
---|
538 | ;
|
---|
539 | xor cx,cx
|
---|
540 | .readTimeoutLoop:
|
---|
541 | mov dl,bh
|
---|
542 | in al,dx
|
---|
543 | test al,ah
|
---|
544 | jnz .readTimeoutComplete
|
---|
545 | loop .readTimeoutLoop
|
---|
546 |
|
---|
547 | ;
|
---|
548 | ; If that loop completes, then we assume there is a long delay involved, turn interrupts back on
|
---|
549 | ; and wait for a given number of timer ticks to pass.
|
---|
550 | ;
|
---|
551 | sti
|
---|
552 | mov cl,SerialCommand_WaitAndPoll_SoftDelayTicks
|
---|
553 | call Timer_InitializeTimeoutWithTicksInCL
|
---|
554 | .WaitAndPoll:
|
---|
555 | call Timer_SetCFifTimeout
|
---|
556 | jc SerialCommand_OutputWithParameters_ErrorAndPop4Words
|
---|
557 | in al,dx
|
---|
558 | test al,ah
|
---|
559 | jz .WaitAndPoll
|
---|
560 | cli
|
---|
561 |
|
---|
562 | .readTimeoutComplete:
|
---|
563 | pop dx
|
---|
564 | pop cx
|
---|
565 | ret
|
---|
566 |
|
---|
567 | ;--------------------------------------------------------------------
|
---|
568 | ; SerialCommand_IdentifyDeviceToBufferInESSIwithDriveSelectByteInBH
|
---|
569 | ; Parameters:
|
---|
570 | ; BH: Drive Select byte for Drive and Head Select Register
|
---|
571 | ; DS: Segment to RAMVARS
|
---|
572 | ; ES:SI: Ptr to buffer to receive 512-byte IDE Information
|
---|
573 | ; CS:BP: Ptr to IDEVARS
|
---|
574 | ; Returns:
|
---|
575 | ; AH: INT 13h Error Code
|
---|
576 | ; NOTE: Not set (or checked) during drive detection
|
---|
577 | ; CF: Cleared if success, Set if error
|
---|
578 | ; Corrupts registers:
|
---|
579 | ; AL, BL, CX, DX, SI, DI, ES
|
---|
580 | ;--------------------------------------------------------------------
|
---|
581 | ALIGN JUMP_ALIGN
|
---|
582 | SerialCommand_IdentifyDeviceToBufferInESSIwithDriveSelectByteInBH:
|
---|
583 | ;
|
---|
584 | ; To improve boot time, we do our best to avoid looking for slave serial drives when we already know the results
|
---|
585 | ; from the looking for a master. This is particularly true when doing a COM port scan, as we will end up running
|
---|
586 | ; through all the COM ports and baud rates a second time.
|
---|
587 | ;
|
---|
588 | ; But drive detection isn't the only case - we also need to get the right drive when called on int13h/25h.
|
---|
589 | ;
|
---|
590 | ; The decision tree:
|
---|
591 | ;
|
---|
592 | ; Master:
|
---|
593 | ; bSerialPackedPortAndBaud Non-Zero: -> Continue with bSerialPackedAndBaud (1)
|
---|
594 | ; bSerialPackedPortAndBaud Zero:
|
---|
595 | ; bLastSerial Zero: -> Scan (2)
|
---|
596 | ; bLastSerial Non-Zero: -> Continue with bLastSerial (3)
|
---|
597 | ;
|
---|
598 | ; Slave:
|
---|
599 | ; bSerialPackedPortAndBaud Non-Zero:
|
---|
600 | ; bLastSerial Zero: -> Error - Not Found (4)
|
---|
601 | ; bLastSerial Non-Zero: -> Continue with bSerialPackedAndBaud (5)
|
---|
602 | ; bSerialPackedPortAndBaud Zero:
|
---|
603 | ; bLastSerial Zero: -> Error - Not Found (4)
|
---|
604 | ; bLastSerial Non-Zero: -> Continue with bLastSerial (6)
|
---|
605 | ;
|
---|
606 | ; (1) This was a port/baud that was explicitly set with the configurator. In the drive detection case, as this
|
---|
607 | ; is the Master, we are checking out a new controller, and so don't care about the value of bLastSerial.
|
---|
608 | ; And as with the int13h/25h case, we just go off and get the needed information using the user's setting.
|
---|
609 | ; (2) We are using the special .ideVarsSerialAuto structure. During drive detection, we would only be here
|
---|
610 | ; if bLastSerial is zero (since we only scan if no explicit drives are set), so we go off to scan.
|
---|
611 | ; (3) We are using the special .ideVarsSerialAuto structure. We won't get here during drive detection, but
|
---|
612 | ; we might get here on an int13h/25h call. If we have scanned COM drives, they are the ONLY serial drives
|
---|
613 | ; in use, and so bLastSerial will reflect the port/baud setting for the scanned COM drives.
|
---|
614 | ; (4) No master has been found yet, therefore no slave should be found. Avoiding the slave reduces boot time,
|
---|
615 | ; especially in the full COM port scan case. Note that this is different from the hardware IDE, where we
|
---|
616 | ; will scan for a slave even if a master is not present. Note that if ANY master had been previously found,
|
---|
617 | ; we will do the slave scan, which isn't harmful, it just wastes time. But the most common case (by a wide
|
---|
618 | ; margin) will be just one serial controller.
|
---|
619 | ; (5) A COM port scan for a master had been previously completed, and a drive was found. In a multiple serial
|
---|
620 | ; controller scenario being called with int13h/25h, we need to use the value in bSerialPackedPortAndBaud
|
---|
621 | ; to make sure we get the proper drive.
|
---|
622 | ; (6) A COM port scan for a master had been previously completed, and a drive was found. We would only get here
|
---|
623 | ; if no serial drive was explicitly set by the user in the configurator or that drive had not been found.
|
---|
624 | ; Instead of performing the full COM port scan for the slave, use the port/baud value stored during the
|
---|
625 | ; master scan.
|
---|
626 | ;
|
---|
627 | mov cx,1 ; 1 sector to move, 0 for non-scan
|
---|
628 | mov dx,[cs:bp+IDEVARS.wSerialPortAndBaud]
|
---|
629 | xor ax,ax
|
---|
630 | push si
|
---|
631 | call FindDPT_ToDSDIforSerialDevice
|
---|
632 | pop si
|
---|
633 | jnc .notfounddpt
|
---|
634 | mov ax,[ds:di+DPT_SERIAL.wSerialPortAndBaud]
|
---|
635 | .notfounddpt:
|
---|
636 |
|
---|
637 | test bh, FLG_DRVNHEAD_DRV
|
---|
638 | jz .master
|
---|
639 |
|
---|
640 | test ax,ax ; Take care of the case that is different between master and slave.
|
---|
641 | jz .error ; Because we do this here, the jz after the "or" below will not be taken
|
---|
642 |
|
---|
643 | ; fall-through
|
---|
644 | .master:
|
---|
645 | test dx,dx
|
---|
646 | jnz .identifyDeviceInDX
|
---|
647 |
|
---|
648 | or dx,ax ; Move bLast into position in dl, as well as test for zero
|
---|
649 | jz .scanSerial
|
---|
650 |
|
---|
651 | ; fall-through
|
---|
652 | .identifyDeviceInDX:
|
---|
653 |
|
---|
654 | push bp ; setup fake IDEREGS_AND_INTPACK
|
---|
655 |
|
---|
656 | push dx
|
---|
657 |
|
---|
658 | push cx
|
---|
659 |
|
---|
660 | mov bl,0a0h ; protocol command to ah and onto stack with bh
|
---|
661 | mov ah,bl
|
---|
662 |
|
---|
663 | push bx
|
---|
664 |
|
---|
665 | mov bp,sp
|
---|
666 | call SerialCommand_OutputWithParameters_DeviceInDX
|
---|
667 |
|
---|
668 | pop bx
|
---|
669 |
|
---|
670 | pop cx
|
---|
671 | pop dx
|
---|
672 |
|
---|
673 | pop bp
|
---|
674 | ;
|
---|
675 | ; place packed port/baud in RAMVARS, read by FinalizeDPT and DetectDrives
|
---|
676 | ;
|
---|
677 | mov [es:si+ATA6.wVendor],dx
|
---|
678 |
|
---|
679 | .notFound:
|
---|
680 | ret
|
---|
681 |
|
---|
682 | ;----------------------------------------------------------------------
|
---|
683 | ;
|
---|
684 | ; SerialCommand_AutoSerial
|
---|
685 | ;
|
---|
686 | ; When the SerialAuto IDEVARS entry is used, scans the COM ports on the machine for a possible serial connection.
|
---|
687 | ;
|
---|
688 |
|
---|
689 | .scanPortAddresses: db DEVICE_SERIAL_COM7 >> 2
|
---|
690 | db DEVICE_SERIAL_COM6 >> 2
|
---|
691 | db DEVICE_SERIAL_COM5 >> 2
|
---|
692 | db DEVICE_SERIAL_COM4 >> 2
|
---|
693 | db DEVICE_SERIAL_COM3 >> 2
|
---|
694 | db DEVICE_SERIAL_COM2 >> 2
|
---|
695 | db DEVICE_SERIAL_COM1 >> 2
|
---|
696 | db 0
|
---|
697 |
|
---|
698 | ALIGN JUMP_ALIGN
|
---|
699 | .scanSerial:
|
---|
700 | mov di,.scanPortAddresses-1
|
---|
701 | mov ch,1 ; tell server that we are scanning
|
---|
702 |
|
---|
703 | .nextPort:
|
---|
704 | inc di ; load next port address
|
---|
705 | xor dh, dh
|
---|
706 | mov dl,[cs:di]
|
---|
707 | eSHL_IM dx, 2 ; shift from one byte to two
|
---|
708 | jz .error
|
---|
709 |
|
---|
710 | ;
|
---|
711 | ; Test for COM port presence, write to and read from registers
|
---|
712 | ;
|
---|
713 | push dx
|
---|
714 | add dl,SerialCommand_UART_lineControl
|
---|
715 | mov al, 09ah
|
---|
716 | out dx, al
|
---|
717 | in al, dx
|
---|
718 | pop dx
|
---|
719 | cmp al, 09ah
|
---|
720 | jnz .nextPort
|
---|
721 |
|
---|
722 | mov al, 0ch
|
---|
723 | out dx, al
|
---|
724 | in al, dx
|
---|
725 | cmp al, 0ch
|
---|
726 | jnz .nextPort
|
---|
727 |
|
---|
728 | ;
|
---|
729 | ; Begin baud rate scan on this port...
|
---|
730 | ;
|
---|
731 | ; On a scan, we support 6 baud rates, starting here and going higher by a factor of two each step, with a
|
---|
732 | ; small jump between 9600 and 38800. These 6 were selected since we wanted to support 9600 baud and 115200,
|
---|
733 | ; *on the server side* if the client side had a 4x clock multiplier, a 2x clock multiplier, or no clock multiplier.
|
---|
734 | ;
|
---|
735 | ; Starting with 30h, that means 30h (2400 baud), 18h (4800 baud), 0ch (9600 baud), and
|
---|
736 | ; 04h (28800 baud), 02h (57600 baud), 01h (115200 baud)
|
---|
737 | ;
|
---|
738 | ; Note: hardware baud multipliers (2x, 4x) will impact the final baud rate and are not known at this level
|
---|
739 | ;
|
---|
740 | mov dh,030h * 2 ; multiply by 2 since we are about to divide by 2
|
---|
741 | mov dl,[cs:di] ; restore single byte port address for scan
|
---|
742 |
|
---|
743 | .nextBaud:
|
---|
744 | shr dh,1
|
---|
745 | jz .nextPort
|
---|
746 | cmp dh,6 ; skip from 6 to 4, to move from the top of the 9600 baud range
|
---|
747 | jnz .testBaud ; to the bottom of the 115200 baud range
|
---|
748 | mov dh,4
|
---|
749 |
|
---|
750 | .testBaud:
|
---|
751 | call .identifyDeviceInDX
|
---|
752 | jc .nextBaud
|
---|
753 |
|
---|
754 | ret
|
---|
755 |
|
---|
756 | .error:
|
---|
757 | stc
|
---|
758 | %if 0
|
---|
759 | mov ah,1 ; setting the error code is unnecessary as this path can only be taken during
|
---|
760 | ; drive detection, and drive detection works off CF and does not check AH
|
---|
761 | %endif
|
---|
762 | ret
|
---|
763 |
|
---|
764 |
|
---|