xref: /netbsd-src/sys/arch/atari/dev/atari5380.c (revision 76dfffe33547c37f8bdd446e3e4ab0f3c16cea4b)
1 /*	$NetBSD: atari5380.c,v 1.20 1996/10/13 04:10:50 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1995 Leo Weppelman.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *      This product includes software developed by Leo Weppelman.
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/device.h>
37 #include <sys/buf.h>
38 #include <scsi/scsi_all.h>
39 #include <scsi/scsi_message.h>
40 #include <scsi/scsiconf.h>
41 
42 #include <m68k/asm_single.h>
43 
44 #include <atari/atari/stalloc.h>
45 
46 /*
47  * Include the driver definitions
48  */
49 #include <atari/dev/ncr5380reg.h>
50 
51 #include <machine/stdarg.h>
52 #include <machine/iomap.h>
53 #include <machine/mfp.h>
54 
55 #if defined(FALCON_SCSI)
56 #include <machine/dma.h>
57 #endif
58 
59 /*
60  * Set the various driver options
61  */
62 #define	NREQ		18	/* Size of issue queue			*/
63 #define	AUTO_SENSE	1	/* Automatically issue a request-sense 	*/
64 
65 #define	DRNAME		ncrscsi	/* used in various prints		*/
66 #undef	DBG_SEL			/* Show the selection process		*/
67 #undef	DBG_REQ			/* Show enqueued/ready requests		*/
68 #undef	DBG_ERR_RET		/* Show requests with != 0 return code	*/
69 #undef	DBG_NOWRITE		/* Do not allow writes to the targets	*/
70 #undef	DBG_PIO			/* Show the polled-I/O process		*/
71 #undef	DBG_INF			/* Show information transfer process	*/
72 #define	DBG_NOSTATIC		/* No static functions, all in DDB trace*/
73 #define	DBG_PID		15	/* Keep track of driver			*/
74 #define	REAL_DMA		/* Use DMA if sensible			*/
75 #if defined(FALCON_SCSI)
76 #define	REAL_DMA_POLL	1	/* 1: Poll for end of DMA-transfer	*/
77 #else
78 #define	REAL_DMA_POLL	0	/* 1: Poll for end of DMA-transfer	*/
79 #endif
80 #undef	USE_PDMA		/* Use special pdma-transfer function	*/
81 #define MIN_PHYS	65536	/*BARF!!!!*/
82 
83 /*
84  * Include more driver definitions
85  */
86 #include <atari/dev/ncr5380var.h>
87 
88 
89 /*
90  * This is crap, but because the interrupts now run at MFP spl-level (6),
91  * splbio() is not enough at some places. The code should be checked to
92  * find out where splhigh() is needed and where splbio() should be used.
93  * Now that I use this interrupt sceme, the spl values are fake!
94  */
95 #undef splbio()
96 #define splbio()	splhigh()
97 
98 /*
99  * The atari specific driver options
100  */
101 #undef	NO_TTRAM_DMA		/* Do not use DMA to TT-ram. This	*/
102 				/*    fails on older atari's		*/
103 #define	ENABLE_NCR5380(sc)	cur_softc = sc;
104 
105 static u_char	*alloc_bounceb __P((u_long));
106 static void	free_bounceb __P((u_char *));
107 static int	machine_match __P((struct device *, void *, void *,
108 							struct cfdriver *));
109        void	scsi_ctrl __P((int));
110        void	scsi_dma __P((int));
111 
112 /*
113  * Functions that do nothing on the atari
114  */
115 #define	pdma_ready()		0
116 
117 #if defined(TT_SCSI)
118 
119 void	ncr5380_drq_intr __P((void));
120 
121 /*
122  * Define all the things we need of the DMA-controller
123  */
124 #define	SCSI_DMA	((struct scsi_dma *)AD_SCSI_DMA)
125 #define	SCSI_5380	((struct scsi_5380 *)AD_NCR5380)
126 
127 struct scsi_dma {
128 	volatile u_char		s_dma_ptr[8];	/* use only the odd bytes */
129 	volatile u_char		s_dma_cnt[8];	/* use only the odd bytes */
130 	volatile u_char		s_dma_res[4];	/* data residue register  */
131 	volatile u_char		s_dma_gap;	/* not used		  */
132 	volatile u_char		s_dma_ctrl;	/* control register	  */
133 	volatile u_char		s_dma_gap2;	/* not used		  */
134 	volatile u_char		s_hdma_ctrl;	/* Hades control register */
135 };
136 
137 #define	set_scsi_dma(addr, val)	(void)(					\
138 	{								\
139 	u_char	*address = (u_char*)addr+1;				\
140 	u_long	nval	 = (u_long)val;					\
141 	__asm("movepl	%0, %1@(0)": :"d" (nval), "a" (address));	\
142 	})
143 
144 #define	get_scsi_dma(addr, res)	(					\
145 	{								\
146 	u_char	*address = (u_char*)addr+1;				\
147 	u_long	nval;							\
148 	__asm("movepl	%1@(0), %0": "=d" (nval) : "a" (address));	\
149 	res = (u_long)nval;						\
150 	})
151 
152 /*
153  * Defines for TT-DMA control register
154  */
155 #define	SD_BUSERR	0x80		/* 1 = transfer caused bus error*/
156 #define	SD_ZERO		0x40		/* 1 = byte counter is zero	*/
157 #define	SD_ENABLE	0x02		/* 1 = Enable DMA		*/
158 #define	SD_OUT		0x01		/* Direction: memory to SCSI	*/
159 #define	SD_IN		0x00		/* Direction: SCSI to memory	*/
160 
161 /*
162  * Defines for Hades-DMA control register
163  */
164 #define	SDH_BUSERR	0x02		/* 1 = Bus error		*/
165 #define SDH_EOP		0x01		/* 1 = Signal EOP on 5380	*/
166 #define	SDH_ZERO	0x40		/* 1 = Byte counter is zero	*/
167 
168 /*
169  * Define the 5380 register set
170  */
171 struct scsi_5380 {
172 	volatile u_char	scsi_5380[16];	/* use only the odd bytes	*/
173 };
174 #endif /* TT_SCSI */
175 
176 /**********************************************
177  * Variables present for both TT and Falcon.  *
178  **********************************************/
179 
180 /*
181  * Softc of currently active controller (a bit of fake; we only have one)
182  */
183 static struct ncr_softc	*cur_softc;
184 
185 #if defined(TT_SCSI) && !defined(FALCON_SCSI)
186 /*
187  * We can be more efficient for some functions when only TT_SCSI is selected
188  */
189 #define	GET_5380_REG(rnum)	SCSI_5380->scsi_5380[(rnum << 1) | 1]
190 #define	SET_5380_REG(rnum,val)	(SCSI_5380->scsi_5380[(rnum << 1) | 1] = val)
191 
192 #define scsi_mach_init(sc)	scsi_tt_init(sc)
193 #define scsi_ienable()		scsi_tt_ienable()
194 #define scsi_idisable()		scsi_tt_idisable()
195 #define	scsi_clr_ipend()	scsi_tt_clr_ipend()
196 #define scsi_ipending()		(GET_5380_REG(NCR5380_DMSTAT) & SC_IRQ_SET)
197 #define scsi_dma_setup(r,p,m)	scsi_tt_dmasetup(r, p, m)
198 #define wrong_dma_range(r,d)	tt_wrong_dma_range(r, d)
199 #define poll_edma(reqp)		tt_poll_edma(reqp)
200 #define get_dma_result(r, b)	tt_get_dma_result(r, b)
201 #define	can_access_5380()	1
202 #define emulated_dma()		((machineid & ATARI_HADES) ? 1 : 0)
203 
204 #define fair_to_keep_dma()	1
205 #define claimed_dma()		1
206 #define reconsider_dma()
207 
208 #endif /* defined(TT_SCSI) && !defined(FALCON_SCSI) */
209 
210 #if defined(TT_SCSI)
211 
212 /*
213  * Prototype functions defined below
214  */
215 #ifdef NO_TTRAM_DMA
216 static int tt_wrong_dma_range __P((SC_REQ *, struct dma_chain *));
217 #endif
218 static void	scsi_tt_init __P((struct ncr_softc *));
219 static u_char	get_tt_5380_reg __P((u_short));
220 static void	set_tt_5380_reg __P((u_short, u_short));
221 static void	scsi_tt_dmasetup __P((SC_REQ *, u_int, u_char));
222 static int	tt_poll_edma __P((SC_REQ *));
223 static u_char	*ptov __P((SC_REQ *, u_long*));
224 static int	tt_get_dma_result __P((SC_REQ *, u_long *));
225        void	scsi_tt_ienable __P((void));
226        void	scsi_tt_idisable __P((void));
227        void	scsi_tt_clr_ipend __P((void));
228 
229 /*
230  * Define these too, so we can use them locally...
231  */
232 #define	GET_TT_REG(rnum)	SCSI_5380->scsi_5380[(rnum << 1) | 1]
233 #define	SET_TT_REG(rnum,val)	(SCSI_5380->scsi_5380[(rnum << 1) | 1] = val)
234 
235 #ifdef NO_TTRAM_DMA
236 static int
237 tt_wrong_dma_range(reqp, dm)
238 SC_REQ			*reqp;
239 struct dma_chain	*dm;
240 {
241 	if (dm->dm_addr & 0xff000000) {
242 		reqp->dr_flag |= DRIVER_BOUNCING;
243 		return(1);
244 	}
245 	return(0);
246 }
247 #else
248 #define	tt_wrong_dma_range(reqp, dm)	0
249 #endif
250 
251 static void
252 scsi_tt_init(struct ncr_softc *sc)
253 {
254 	/*
255 	 * Enable SCSI-related interrupts
256 	 */
257 	MFP2->mf_aer  |= 0x80;		/* SCSI IRQ goes HIGH!!!!!	*/
258 
259 	if (machineid & ATARI_TT) {
260 		/* SCSI-dma interrupts		*/
261 		MFP2->mf_ierb |= IB_SCDM;
262 		MFP2->mf_iprb &= ~IB_SCDM;
263 		MFP2->mf_imrb |= IB_SCDM;
264 	}
265 	else SCSI_DMA->s_hdma_ctrl = 0;
266 
267 	MFP2->mf_iera |= IA_SCSI;	/* SCSI-5380 interrupts		*/
268 	MFP2->mf_ipra &= ~IA_SCSI;
269 	MFP2->mf_imra |= IA_SCSI;
270 
271 	/*
272 	 * LWP: DMA transfers to TT-ram causes data to be garbeled
273 	 * without notice on some revisons of the TT-mainboard.
274 	 * When program's generate misterious Segmentations faults,
275 	 * try turning on NO_TTRAM_DMA.
276 	 */
277 #ifdef NO_TTRAM_DMA
278 	printf(": DMA to TT-RAM is disabled!");
279 #endif
280 }
281 
282 static u_char
283 get_tt_5380_reg(u_short rnum)
284 {
285 	return(SCSI_5380->scsi_5380[(rnum << 1) | 1]);
286 }
287 
288 static void
289 set_tt_5380_reg(u_short rnum, u_short val)
290 {
291 	SCSI_5380->scsi_5380[(rnum << 1) | 1] = val;
292 }
293 
294 extern __inline__ void
295 scsi_tt_ienable(void)
296 {
297 	if (machineid & ATARI_TT)
298 		single_inst_bset_b(MFP2->mf_imrb, IB_SCDM);
299 	single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
300 }
301 
302 extern __inline__ void
303 scsi_tt_idisable(void)
304 {
305 	if (machineid & ATARI_TT)
306 		single_inst_bclr_b(MFP2->mf_imrb, IB_SCDM);
307 	single_inst_bclr_b(MFP2->mf_imra, IA_SCSI);
308 }
309 
310 extern __inline__ void
311 scsi_tt_clr_ipend(void)
312 {
313 	int	tmp;
314 
315 	SCSI_DMA->s_dma_ctrl = 0;
316 	tmp = GET_TT_REG(NCR5380_IRCV);
317 	if (machineid & ATARI_TT)
318 		single_inst_bclr_b(MFP2->mf_iprb, IB_SCDM);
319 	single_inst_bclr_b(MFP2->mf_ipra, IA_SCSI);
320 }
321 
322 static void
323 scsi_tt_dmasetup(SC_REQ *reqp, u_int phase, u_char	mode)
324 {
325 	if (PH_IN(phase)) {
326 		SCSI_DMA->s_dma_ctrl = SD_IN;
327 		if (machineid & ATARI_HADES)
328 		    SCSI_DMA->s_hdma_ctrl &= ~(SDH_BUSERR|SDH_EOP);
329 		set_scsi_dma(&(SCSI_DMA->s_dma_ptr), reqp->dm_cur->dm_addr);
330 		set_scsi_dma(&(SCSI_DMA->s_dma_cnt), reqp->dm_cur->dm_count);
331 		SET_TT_REG(NCR5380_ICOM, 0);
332 		SET_TT_REG(NCR5380_MODE, mode);
333 		SCSI_DMA->s_dma_ctrl = SD_ENABLE;
334 		SET_TT_REG(NCR5380_IRCV, 0);
335 	}
336 	else {
337 		SCSI_DMA->s_dma_ctrl = SD_OUT;
338 		if (machineid & ATARI_HADES)
339 		    SCSI_DMA->s_hdma_ctrl &= ~(SDH_BUSERR|SDH_EOP);
340 		set_scsi_dma(&(SCSI_DMA->s_dma_ptr), reqp->dm_cur->dm_addr);
341 		set_scsi_dma(&(SCSI_DMA->s_dma_cnt), reqp->dm_cur->dm_count);
342 		SET_TT_REG(NCR5380_MODE, mode);
343 		SET_TT_REG(NCR5380_ICOM, SC_ADTB);
344 		SET_TT_REG(NCR5380_DMSTAT, 0);
345 		SCSI_DMA->s_dma_ctrl = SD_ENABLE|SD_OUT;
346 	}
347 }
348 
349 static int
350 tt_poll_edma(SC_REQ *reqp)
351 {
352 	u_char	dmstat, dmastat;
353 	int	timeout = 9000; /* XXX */
354 
355 	/*
356 	 * We wait here until the DMA has finished. This can be
357 	 * achieved by checking the following conditions:
358 	 *   - 5380:
359 	 *	- End of DMA flag is set
360 	 *	- We lost BSY (error!!)
361 	 *	- A phase mismatch has occured (partial transfer)
362 	 *   - DMA-controller:
363 	 *	- A bus error occurred (Kernel error!!)
364 	 *	- All bytes are transferred
365 	 * If one of the terminating conditions was met, we call
366 	 * 'dma_ready' to check errors and perform the bookkeeping.
367 	 */
368 
369 	for (;;) {
370 		delay(20);
371 		if (--timeout <= 0) {
372 			ncr_tprint(reqp, "timeout on polled transfer\n");
373 			reqp->xs->error = XS_TIMEOUT;
374 			return(0);
375 		}
376 		dmstat  = GET_TT_REG(NCR5380_DMSTAT);
377 		dmastat = SCSI_DMA->s_dma_ctrl;
378 		if (dmstat & (SC_END_DMA|SC_BSY_ERR|SC_IRQ_SET))
379 			break;
380 		if (!(dmstat & SC_PHS_MTCH))
381 			break;
382 		if (dmastat & (SD_BUSERR|SD_ZERO))
383 			break;
384 	}
385 	return(1);
386 }
387 
388 /*
389  * Convert physical DMA address to a virtual address.
390  */
391 static u_char *
392 ptov(SC_REQ *reqp, u_long *phaddr)
393 {
394 	struct dma_chain	*dm;
395 	u_char			*vaddr;
396 
397 	dm = reqp->dm_chain;
398 	vaddr = reqp->xdata_ptr;
399 	for(; dm < reqp->dm_cur; dm++)
400 		vaddr += dm->dm_count;
401 	vaddr += (u_long)phaddr - dm->dm_addr;
402 	return(vaddr);
403 }
404 
405 static int
406 tt_get_dma_result(SC_REQ *reqp, u_long *bytes_left)
407 {
408 	int	dmastat, dmstat;
409 	u_char	*byte_p;
410 	u_long	leftover;
411 
412 	dmastat = SCSI_DMA->s_dma_ctrl;
413 	dmstat  = GET_TT_REG(NCR5380_DMSTAT);
414 	get_scsi_dma(SCSI_DMA->s_dma_cnt, leftover);
415 	get_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)byte_p);
416 
417 	if (dmastat & SD_BUSERR) {
418 		/*
419 		 * The DMA-controller seems to access 8 bytes beyond
420 		 * it's limits on output. Therefore check also the byte
421 		 * count. If it's zero, ignore the bus error.
422 		 */
423 		if (leftover != 0) {
424 			ncr_tprint(reqp,
425 				"SCSI-DMA buserror - accessing 0x%x\n", byte_p);
426 			reqp->xs->error = XS_DRIVER_STUFFUP;
427 		}
428 	}
429 
430 	/*
431 	 * We handle the following special condition below:
432 	 *  -- The device disconnects in the middle of a write operation --
433 	 * In this case, the 5380 has already pre-fetched the next byte from
434 	 * the DMA-controller before the phase mismatch occurs. Therefore,
435 	 * leftover is 1 too low.
436 	 * This does not always happen! Therefore, we only do this when
437 	 * leftover is odd. This assumes that DMA transfers are _even_! This
438 	 * is normally the case on disks and types but might not always be.
439 	 * XXX: Check if ACK is consistently high on these occasions LWP
440 	 */
441 	if ((leftover & 1) && !(dmstat & SC_PHS_MTCH) && PH_OUT(reqp->phase))
442 		leftover++;
443 
444 	/*
445 	 * Check if there are some 'restbytes' left in the DMA-controller.
446 	 */
447 	if ((machineid & ATARI_TT) && ((u_long)byte_p & 3)
448 	    && PH_IN(reqp->phase)) {
449 		u_char	*p, *q;
450 
451 		p = ptov(reqp, (u_long *)((u_long)byte_p & ~3));
452 		q = (u_char*)&(SCSI_DMA->s_dma_res);
453 		switch ((u_long)byte_p & 3) {
454 			case 3: *p++ = *q++;
455 			case 2: *p++ = *q++;
456 			case 1: *p++ = *q++;
457 		}
458 	}
459 	*bytes_left = leftover;
460 	return ((dmastat & (SD_BUSERR|SD_ZERO)) ? 1 : 0);
461 }
462 
463 static u_char *dma_ptr;
464 static int dbgflag = 3;
465 void
466 ncr5380_drq_intr()
467 {
468 extern	int			*nofault;
469 	label_t			faultbuf;
470 	int			write;
471 	u_long	 		count;
472 	u_char			*data_p = (u_char*)(stio_addr+0x741);
473 
474 	/*
475 	 * Block SCSI interrupts while emulating DMA. They come
476 	 * at a higher priority.
477 	 */
478 	single_inst_bclr_b(MFP2->mf_imra, ~IA_SCSI);
479 
480 	/*
481 	 * Setup for a possible bus error caused by SCSI controller
482 	 * switching out of DATA-IN/OUT before we're done with the
483 	 * current transfer.
484 	 */
485 	nofault = (int *) &faultbuf;
486 
487 	if (setjmp((label_t *) nofault)) {
488 		u_char	*ptr;
489 		u_long	cnt, tmp;
490 
491 		PID("drq berr");
492 		nofault = (int *) 0;
493 
494 		/*
495 		 * Determine number of bytes transferred
496 		 */
497 		get_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)ptr);
498 		cnt = dma_ptr - ptr;
499 
500 		if (cnt != 0) {
501 			/*
502 			 * Update the dma pointer/count fields
503 			 */
504 			set_scsi_dma(SCSI_DMA->s_dma_ptr, dma_ptr);
505 			get_scsi_dma(SCSI_DMA->s_dma_cnt, tmp);
506 			set_scsi_dma(SCSI_DMA->s_dma_cnt, tmp - cnt);
507 
508 			if (tmp > cnt) {
509 				/*
510 				 * Still more to transfer
511 				 */
512 				single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
513 				return;
514 			}
515 
516 			/*
517 			 * Signal EOP to 5380
518 			 */
519 			SCSI_DMA->s_hdma_ctrl |= SDH_EOP;
520 		}
521 		else {
522 			/*
523 			 * Set the bus-error bit
524 			 */
525 			SCSI_DMA->s_hdma_ctrl |= SDH_BUSERR;
526 		}
527 
528 		/*
529 		 * Schedule an interrupt
530 		 */
531 		if (SCSI_DMA->s_dma_ctrl & SD_ENABLE)
532 		    add_sicallback((si_farg)ncr_dma_intr, (void *)cur_softc, 0);
533 
534 		/*
535 		 * Clear DMA-mode
536 		 */
537 		SCSI_DMA->s_dma_ctrl &= ~SD_ENABLE;
538 		single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
539 
540 		return;
541 	}
542 
543 	write = (SCSI_DMA->s_dma_ctrl & SD_OUT) ? 1 : 0;
544 #if DBG_PID
545 	if (write) {
546 		PID("drq (in)");
547 	} else {
548 		PID("drq (out)");
549 	}
550 #endif
551 
552 	get_scsi_dma(SCSI_DMA->s_dma_cnt, count);
553 	get_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)dma_ptr);
554 
555 	/*
556 	 * Keep pushing bytes until we're done or a bus-error
557 	 * signals that the SCSI controller is not ready.
558 	 * NOTE: I tried some optimalizations in these loops,
559 	 *       but they had no effect on transfer speed.
560 	 */
561 	if (write) {
562 		while(count--) {
563 			*data_p = *dma_ptr++;
564 		}
565 	}
566 	else {
567 		while(count--) {
568 			*dma_ptr++ = *data_p;
569 		}
570 	}
571 
572 	/*
573 	 * Schedule an interrupt
574 	 */
575 	if (SCSI_DMA->s_dma_ctrl & SD_ENABLE)
576 	    add_sicallback((si_farg)ncr_dma_intr, (void *)cur_softc, 0);
577 
578 	/*
579 	 * Clear DMA-mode
580 	 */
581 	SCSI_DMA->s_dma_ctrl &= ~SD_ENABLE;
582 
583 	/*
584 	 * OK.  No bus error occurred above.  Clear the nofault flag
585 	 * so we no longer short-circuit bus errors.
586 	 */
587 	nofault = (int *) 0;
588 
589 	/*
590 	 * Update the DMA 'registers' to reflect that all bytes
591 	 * have been transfered and tell this to the 5380 too.
592 	 */
593 	set_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)dma_ptr);
594 	set_scsi_dma(SCSI_DMA->s_dma_cnt, 0);
595 	SCSI_DMA->s_hdma_ctrl |= SDH_EOP;
596 
597 	PID("end drq");
598 	single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
599 
600 	return;
601 }
602 
603 #endif /* defined(TT_SCSI) */
604 
605 #if defined(FALCON_SCSI) && !defined(TT_SCSI)
606 
607 #define	GET_5380_REG(rnum)	get_falcon_5380_reg(rnum)
608 #define	SET_5380_REG(rnum,val)	set_falcon_5380_reg(rnum, val)
609 #define scsi_mach_init(sc)	scsi_falcon_init(sc)
610 #define scsi_ienable()		scsi_falcon_ienable()
611 #define scsi_idisable()		scsi_falcon_idisable()
612 #define	scsi_clr_ipend()	scsi_falcon_clr_ipend()
613 #define	scsi_ipending()		scsi_falcon_ipending()
614 #define scsi_dma_setup(r,p,m)	scsi_falcon_dmasetup(r, p, m)
615 #define wrong_dma_range(r,d)	falcon_wrong_dma_range(r, d)
616 #define poll_edma(reqp)		falcon_poll_edma(reqp)
617 #define get_dma_result(r, b)	falcon_get_dma_result(r, b)
618 #define	can_access_5380()	falcon_can_access_5380()
619 #define	emulated_dma()		0
620 
621 #define fair_to_keep_dma()	(!st_dmawanted())
622 #define claimed_dma()		falcon_claimed_dma()
623 #define reconsider_dma()	falcon_reconsider_dma()
624 
625 #endif /* defined(FALCON_SCSI) && !defined(TT_SCSI) */
626 
627 #if defined(FALCON_SCSI)
628 
629 /*
630  * Prototype functions defined below
631  */
632 static void	scsi_falcon_init __P((struct ncr_softc *));
633 static u_char	get_falcon_5380_reg __P((u_short));
634 static void	set_falcon_5380_reg __P((u_short, u_short));
635 static int	falcon_wrong_dma_range __P((SC_REQ *, struct dma_chain *));
636 static void	fal1_dma __P((u_int, u_int, SC_REQ *));
637 static void	scsi_falcon_dmasetup __P((SC_REQ  *, u_int, u_char));
638 static int	falcon_poll_edma __P((SC_REQ  *));
639 static int	falcon_get_dma_result __P((SC_REQ  *, u_long *));
640        int	falcon_can_access_5380 __P((void));
641        void	scsi_falcon_clr_ipend __P((void));
642        void	scsi_falcon_idisable __P((void));
643        void	scsi_falcon_ienable __P((void));
644        int	scsi_falcon_ipending __P((void));
645        int	falcon_claimed_dma __P((void));
646        void	falcon_reconsider_dma __P((void));
647 
648 static void
649 scsi_falcon_init(sc)
650 struct ncr_softc	*sc;
651 {
652 	/*
653 	 * Enable disk related interrupts
654 	 */
655 	MFP->mf_ierb  |= IB_DINT;
656 	MFP->mf_iprb  &= ~IB_DINT;
657 	MFP->mf_imrb  |= IB_DINT;
658 }
659 
660 static u_char
661 get_falcon_5380_reg(rnum)
662 u_short	rnum;
663 {
664 	DMA->dma_mode = DMA_SCSI + rnum;
665 	return(DMA->dma_data);
666 }
667 
668 static void
669 set_falcon_5380_reg(rnum, val)
670 u_short	rnum, val;
671 {
672 	DMA->dma_mode = DMA_SCSI + rnum;
673 	DMA->dma_data = val;
674 }
675 
676 extern __inline__ void
677 scsi_falcon_ienable()
678 {
679 	single_inst_bset_b(MFP->mf_ierb, IB_DINT);
680 }
681 
682 extern __inline__ void
683 scsi_falcon_idisable()
684 {
685 	single_inst_bclr_b(MFP->mf_ierb, ~IB_DINT);
686 }
687 
688 extern __inline__ void
689 scsi_falcon_clr_ipend()
690 {
691 	int	tmp;
692 
693 	tmp = get_falcon_5380_reg(NCR5380_IRCV);
694 	rem_sicallback((si_farg)ncr_ctrl_intr);
695 }
696 
697 extern __inline__ int
698 scsi_falcon_ipending()
699 {
700 	if (connected && (connected->dr_flag & DRIVER_IN_DMA)) {
701 		/*
702 		 *  XXX: When DMA is running, we are only allowed to
703 		 *       check the 5380 when DMA _might_ be finished.
704 		 */
705 		if (MFP->mf_gpip & IO_DINT)
706 		    return (0); /* XXX: Actually: we're not allowed to check */
707 
708 		/* LWP: 28-06, must be a dma interrupt! should the
709 		 * ST-DMA unit be taken out of dma mode?????
710 		 */
711 		DMA->dma_mode = 0x90;
712 
713 	}
714 	return(get_falcon_5380_reg(NCR5380_DMSTAT) & SC_IRQ_SET);
715 }
716 
717 static int
718 falcon_wrong_dma_range(reqp, dm)
719 SC_REQ			*reqp;
720 struct dma_chain	*dm;
721 {
722 	/*
723 	 * Do not allow chains yet! See also comment with
724 	 * falcon_poll_edma() !!!
725 	 */
726 	if (((dm - reqp->dm_chain) > 0) || (dm->dm_addr & 0xff000000)) {
727 		reqp->dr_flag |= DRIVER_BOUNCING;
728 		return(1);
729 	}
730 	/*
731 	 * Never allow DMA to happen on a Falcon when the transfer
732 	 * size is no multiple of 512. This is the transfer unit of the
733 	 * ST DMA-controller.
734 	 */
735 	if(dm->dm_count & 511)
736 		return(1);
737 	return(0);
738 }
739 
740 static	int falcon_lock = 0;
741 
742 extern __inline__ int
743 falcon_claimed_dma()
744 {
745 	if (falcon_lock != DMA_LOCK_GRANT) {
746 		if (falcon_lock == DMA_LOCK_REQ) {
747 			/*
748 			 * DMA access is being claimed.
749 			 */
750 			return(0);
751 		}
752 		if (!st_dmagrab((dma_farg)ncr_ctrl_intr, (dma_farg)run_main,
753 						cur_softc, &falcon_lock, 1))
754 			return(0);
755 	}
756 	return(1);
757 }
758 
759 extern __inline__ void
760 falcon_reconsider_dma()
761 {
762 	if (falcon_lock && (connected == NULL) && (discon_q == NULL)) {
763 		/*
764 		 * No need to keep DMA locked by us as we are not currently
765 		 * connected and no disconnected jobs are pending.
766 		 */
767 		rem_sicallback((si_farg)ncr_ctrl_intr);
768 		st_dmafree(cur_softc, &falcon_lock);
769 	}
770 
771 	if (!falcon_lock && (issue_q != NULL)) {
772 		/*
773 		 * We must (re)claim DMA access as there are jobs
774 		 * waiting in the issue queue.
775 		 */
776 		st_dmagrab((dma_farg)ncr_ctrl_intr, (dma_farg)run_main,
777 						cur_softc, &falcon_lock, 0);
778 	}
779 }
780 
781 static void
782 fal1_dma(dir, nsects, reqp)
783 u_int	dir, nsects;
784 SC_REQ	*reqp;
785 {
786 	dir <<= 8;
787 	st_dmaaddr_set((caddr_t)reqp->dm_cur->dm_addr);
788 	DMA->dma_mode = 0x90 | dir;
789 	DMA->dma_mode = 0x90 | (dir ^ DMA_WRBIT);
790 	DMA->dma_mode = 0x90 | dir;
791 	DMA->dma_data = nsects;
792 	delay(2);	/* _really_ needed (Thomas Gerner) */
793 	DMA->dma_mode = 0x10 | dir;
794 }
795 
796 static void
797 scsi_falcon_dmasetup(reqp, phase, mode)
798 SC_REQ	*reqp;
799 u_int	phase;
800 u_char	mode;
801 {
802 	int	nsects = reqp->dm_cur->dm_count / 512; /* XXX */
803 
804 	/*
805 	 * XXX: We should probably clear the fifo before putting the
806 	 *      5380 into DMA-mode.
807 	 */
808 	if (PH_IN(phase)) {
809 		set_falcon_5380_reg(NCR5380_ICOM, 0);
810 		set_falcon_5380_reg(NCR5380_MODE, mode);
811 		set_falcon_5380_reg(NCR5380_IRCV, 0);
812 		fal1_dma(0, nsects, reqp);
813 	}
814 	else {
815 		set_falcon_5380_reg(NCR5380_MODE, mode);
816 		set_falcon_5380_reg(NCR5380_ICOM, SC_ADTB);
817 		set_falcon_5380_reg(NCR5380_DMSTAT, 0);
818 		fal1_dma(1, nsects, reqp);
819 	}
820 }
821 
822 static int
823 falcon_poll_edma(reqp)
824 SC_REQ	*reqp;
825 {
826 	int	timeout = 9000; /* XXX */
827 
828 	/*
829 	 * Because of the Falcon hardware, it is impossible to reach
830 	 * the 5380 while doing DMA-transfers. So we have to rely on
831 	 * the interrupt line to determine if DMA-has finished. the
832 	 * DMA-controller itself will never fire an interrupt. This means
833 	 * that 'broken-up' DMA transfers are not (yet) possible on the
834 	 * Falcon.
835 	 */
836 	for (;;) {
837 		delay(20);
838 		if (--timeout <= 0) {
839 			ncr_tprint(reqp, "Timeout on polled transfer\n");
840 			reqp->xs->error = XS_TIMEOUT;
841 			return(0);
842 		}
843 		if (!(MFP->mf_gpip & IO_DINT))
844 			break;
845 	}
846 	return(1);
847 }
848 
849 static int
850 falcon_get_dma_result(reqp, bytes_left)
851 SC_REQ	*reqp;
852 u_long	*bytes_left;
853 {
854 	int	rv = 0;
855 	int	st_dmastat;
856 	u_long	bytes_done;
857 
858 	/*
859 	 * Select sector counter register first (See Atari docu.)
860 	 */
861 	DMA->dma_mode = 0x90;
862 	if (!(st_dmastat = DMA->dma_stat) & 0x01) {
863 		/*
864 		 * Misc. DMA-error according to Atari...
865 		 */
866 		ncr_tprint(reqp, "Unknow ST-SCSI error near 0x%x\n",
867 							st_dmaaddr_get());
868 		reqp->xs->error = XS_DRIVER_STUFFUP;
869 		rv = 1;
870 	}
871 	/*
872 	 * Because we NEVER start DMA on the Falcon when the data size
873 	 * is not a multiple of 512 bytes, we can safely round down the
874 	 * byte count on writes. We need to because in case of a disconnect,
875 	 * the DMA has already prefetched the next couple of bytes.
876 	 * On read, these byte counts are an error. They are logged and
877 	 * should be handled by the mi-part of the driver.
878 	 * NOTE: We formerly did this by using the 'byte-count-zero' bit
879 	 *       of the DMA controller, but this didn't seem to work???
880          *       [lwp 29/06/96]
881 	 */
882 	bytes_done = st_dmaaddr_get() - reqp->dm_cur->dm_addr;
883 	if (bytes_done & 511) {
884 		if (PH_IN(reqp->phase)) {
885 			ncr_tprint(reqp, "Byte count on read not a multiple "
886 					 "of 512 (%ld)\n", bytes_done);
887 		}
888 		bytes_done &= ~511;
889 	}
890 	if ((*bytes_left = reqp->dm_cur->dm_count - bytes_done) == 0)
891 		rv = 1;
892 	return(rv);
893 }
894 
895 static int
896 falcon_can_access_5380()
897 {
898 	if (connected && (connected->dr_flag & DRIVER_IN_DMA)
899 		&& (MFP->mf_gpip & IO_DINT))
900 			return(0);
901 	return(1);
902 }
903 
904 #endif /* defined(FALCON_SCSI) */
905 
906 #if defined(TT_SCSI) && defined(FALCON_SCSI)
907 /*
908  * Define some functions to support _both_ TT and Falcon SCSI
909  */
910 
911 /*
912  * The prototypes first...
913  */
914 static void	scsi_mach_init __P((struct ncr_softc *));
915        void	scsi_ienable __P((void));
916        void	scsi_idisable __P((void));
917        void	scsi_clr_ipend __P((void));
918        int	scsi_ipending __P((void));
919        void	scsi_dma_setup __P((SC_REQ *, u_int, u_char));
920        int	wrong_dma_range __P((SC_REQ *, struct dma_chain *));
921        int	poll_edma __P((SC_REQ *));
922        int	get_dma_result __P((SC_REQ *, u_long *));
923        int	can_access_5380 __P((void));
924 
925 /*
926  * Register access will be done through the following 2 function pointers.
927  */
928 static u_char	(*get_5380_reg) __P((u_short));
929 static void	(*set_5380_reg) __P((u_short, u_short));
930 
931 #define	GET_5380_REG	(*get_5380_reg)
932 #define	SET_5380_REG	(*set_5380_reg)
933 
934 static void
935 scsi_mach_init(sc)
936 struct ncr_softc	*sc;
937 {
938 	if (machineid & ATARI_FALCON) {
939 		get_5380_reg = get_falcon_5380_reg;
940 		set_5380_reg = set_falcon_5380_reg;
941 		scsi_falcon_init(sc);
942 	}
943 	else {
944 		get_5380_reg = get_tt_5380_reg;
945 		set_5380_reg = set_tt_5380_reg;
946 		scsi_tt_init(sc);
947 	}
948 }
949 
950 extern __inline__ void
951 scsi_ienable()
952 {
953 	if (machineid & ATARI_FALCON)
954 		scsi_falcon_ienable();
955 	else scsi_tt_ienable();
956 }
957 
958 extern __inline__ void
959 scsi_idisable()
960 {
961 	if (machineid & ATARI_FALCON)
962 		scsi_falcon_idisable();
963 	else scsi_tt_idisable();
964 }
965 
966 extern __inline__ void
967 scsi_clr_ipend()
968 {
969 	if (machineid & ATARI_FALCON)
970 		scsi_falcon_clr_ipend();
971 	else scsi_tt_clr_ipend();
972 }
973 
974 extern __inline__ int
975 scsi_ipending()
976 {
977 	if (machineid & ATARI_FALCON)
978 		return(scsi_falcon_ipending());
979 	else return (GET_TT_REG(NCR5380_DMSTAT) & SC_IRQ_SET);
980 }
981 
982 extern __inline__ void
983 scsi_dma_setup(reqp, phase, mbase)
984 SC_REQ	*reqp;
985 u_int	phase;
986 u_char	mbase;
987 {
988 	if (machineid & ATARI_FALCON)
989 		scsi_falcon_dmasetup(reqp, phase, mbase);
990 	else scsi_tt_dmasetup(reqp, phase, mbase);
991 }
992 
993 extern __inline__ int
994 wrong_dma_range(reqp, dm)
995 SC_REQ			*reqp;
996 struct dma_chain	*dm;
997 {
998 	if (machineid & ATARI_FALCON)
999 		return(falcon_wrong_dma_range(reqp, dm));
1000 	else return(tt_wrong_dma_range(reqp, dm));
1001 }
1002 
1003 extern __inline__ int
1004 poll_edma(reqp)
1005 SC_REQ	*reqp;
1006 {
1007 	if (machineid & ATARI_FALCON)
1008 		return(falcon_poll_edma(reqp));
1009 	else return(tt_poll_edma(reqp));
1010 }
1011 
1012 extern __inline__ int
1013 get_dma_result(reqp, bytes_left)
1014 SC_REQ	*reqp;
1015 u_long	*bytes_left;
1016 {
1017 	if (machineid & ATARI_FALCON)
1018 		return(falcon_get_dma_result(reqp, bytes_left));
1019 	else return(tt_get_dma_result(reqp, bytes_left));
1020 }
1021 
1022 extern __inline__ int
1023 can_access_5380()
1024 {
1025 	if (machineid & ATARI_FALCON)
1026 		return(falcon_can_access_5380());
1027 	return(1);
1028 }
1029 
1030 #define emulated_dma()		((machineid & ATARI_HADES) ? 1 : 0)
1031 
1032 /*
1033  * Locking stuff. All turns into NOP's on the TT.
1034  */
1035 #define	fair_to_keep_dma()	((machineid & ATARI_FALCON) ?		\
1036 						!st_dmawanted() : 1)
1037 #define	claimed_dma()		((machineid & ATARI_FALCON) ?		\
1038 						falcon_claimed_dma() : 1)
1039 #define reconsider_dma()	{					\
1040 					if(machineid & ATARI_FALCON)	\
1041 						falcon_reconsider_dma();\
1042 				}
1043 #endif /* defined(TT_SCSI) && defined(FALCON_SCSI) */
1044 
1045 /**********************************************
1046  * Functions present for both TT and Falcon.  *
1047  **********************************************/
1048 /*
1049  * Our autoconfig matching function
1050  */
1051 static int
1052 machine_match(struct device *pdp, void *match, void *auxp,
1053 						struct cfdriver *cd)
1054 {
1055 	struct cfdata *cdp = match;
1056 
1057 	if (strcmp(auxp, cd->cd_name))
1058 		return(0);
1059 	if (cdp->cf_unit != 0)	/* Only one unit	*/
1060 		return(0);
1061 	return(1);
1062 }
1063 
1064 /*
1065  * Bounce buffer (de)allocation. Those buffers are gotten from the ST-mem
1066  * pool. Allocation here is both contiguous and in the lower 16Mb of
1067  * the address space. Thus being DMA-able for all controllers.
1068  */
1069 static u_char *
1070 alloc_bounceb(u_long len)
1071 {
1072 	void	*tmp;
1073 
1074 	return((u_char *)alloc_stmem(len, &tmp));
1075 }
1076 
1077 static void
1078 free_bounceb(u_char *bounceb)
1079 {
1080 	free_stmem(bounceb);
1081 }
1082 
1083 /*
1084  * 5380 interrupt.
1085  */
1086 void
1087 scsi_ctrl(int sr)
1088 {
1089 	if (GET_5380_REG(NCR5380_DMSTAT) & SC_IRQ_SET) {
1090 		scsi_idisable();
1091 		if (!BASEPRI(sr))
1092 			add_sicallback((si_farg)ncr_ctrl_intr,
1093 						(void *)cur_softc, 0);
1094 		else {
1095 			spl1();
1096 			ncr_ctrl_intr(cur_softc);
1097 			spl0();
1098 		}
1099 	}
1100 }
1101 
1102 /*
1103  * DMA controller interrupt
1104  */
1105 void
1106 scsi_dma(int sr)
1107 {
1108 	SC_REQ	*reqp;
1109 
1110 	if ((reqp = connected) && (reqp->dr_flag & DRIVER_IN_DMA)) {
1111 		scsi_idisable();
1112 		if (!BASEPRI(sr))
1113 			add_sicallback((si_farg)ncr_dma_intr,
1114 					(void *)cur_softc, 0);
1115 		else {
1116 			spl1();
1117 			ncr_dma_intr(cur_softc);
1118 			spl0();
1119 		}
1120 	}
1121 }
1122 
1123 /*
1124  * Last but not least... Include the general driver code
1125  */
1126 #include <atari/dev/ncr5380.c>
1127