xref: /netbsd-src/sys/arch/atari/dev/atari5380.c (revision d0fed6c87ddc40a8bffa6f99e7433ddfc864dd83)
1 /*	$NetBSD: atari5380.c,v 1.25 1997/04/06 12:42:44 leo 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 #include <atari/atari/intr.h>
56 
57 #if defined(FALCON_SCSI)
58 #include <machine/dma.h>
59 #endif
60 
61 /*
62  * Set the various driver options
63  */
64 #define	NREQ		18	/* Size of issue queue			*/
65 #define	AUTO_SENSE	1	/* Automatically issue a request-sense 	*/
66 
67 #define	DRNAME		ncrscsi	/* used in various prints		*/
68 #undef	DBG_SEL			/* Show the selection process		*/
69 #undef	DBG_REQ			/* Show enqueued/ready requests		*/
70 #undef	DBG_ERR_RET		/* Show requests with != 0 return code	*/
71 #undef	DBG_NOWRITE		/* Do not allow writes to the targets	*/
72 #undef	DBG_PIO			/* Show the polled-I/O process		*/
73 #undef	DBG_INF			/* Show information transfer process	*/
74 #define	DBG_NOSTATIC		/* No static functions, all in DDB trace*/
75 #define	DBG_PID		15	/* Keep track of driver			*/
76 #define	REAL_DMA		/* Use DMA if sensible			*/
77 #if defined(FALCON_SCSI)
78 #define	REAL_DMA_POLL	1	/* 1: Poll for end of DMA-transfer	*/
79 #else
80 #define	REAL_DMA_POLL	0	/* 1: Poll for end of DMA-transfer	*/
81 #endif
82 #undef	USE_PDMA		/* Use special pdma-transfer function	*/
83 #define MIN_PHYS	65536	/*BARF!!!!*/
84 
85 /*
86  * Include more driver definitions
87  */
88 #include <atari/dev/ncr5380var.h>
89 
90 /*
91  * The atari specific driver options
92  */
93 #undef	NO_TTRAM_DMA		/* Do not use DMA to TT-ram. This	*/
94 				/*    fails on older atari's		*/
95 #define	ENABLE_NCR5380(sc)	cur_softc = sc;
96 
97 static u_char	*alloc_bounceb __P((u_long));
98 static void	free_bounceb __P((u_char *));
99 static int	machine_match __P((struct device *, void *, void *,
100 							struct cfdriver *));
101        void	scsi_ctrl __P((int));
102        void	scsi_dma __P((int));
103 
104 /*
105  * Functions that do nothing on the atari
106  */
107 #define	pdma_ready()		0
108 
109 #if defined(TT_SCSI)
110 
111 void	ncr5380_drq_intr __P((void));
112 
113 /*
114  * Define all the things we need of the DMA-controller
115  */
116 #define	SCSI_DMA	((struct scsi_dma *)AD_SCSI_DMA)
117 #define	SCSI_5380	((struct scsi_5380 *)AD_NCR5380)
118 
119 struct scsi_dma {
120 	volatile u_char		s_dma_ptr[8];	/* use only the odd bytes */
121 	volatile u_char		s_dma_cnt[8];	/* use only the odd bytes */
122 	volatile u_char		s_dma_res[4];	/* data residue register  */
123 	volatile u_char		s_dma_gap;	/* not used		  */
124 	volatile u_char		s_dma_ctrl;	/* control register	  */
125 	volatile u_char		s_dma_gap2;	/* not used		  */
126 	volatile u_char		s_hdma_ctrl;	/* Hades control register */
127 };
128 
129 #define	set_scsi_dma(addr, val)	(void)(					\
130 	{								\
131 	u_char	*address = (u_char*)addr+1;				\
132 	u_long	nval	 = (u_long)val;					\
133 	__asm("movepl	%0, %1@(0)": :"d" (nval), "a" (address));	\
134 	})
135 
136 #define	get_scsi_dma(addr, res)	(					\
137 	{								\
138 	u_char	*address = (u_char*)addr+1;				\
139 	u_long	nval;							\
140 	__asm("movepl	%1@(0), %0": "=d" (nval) : "a" (address));	\
141 	res = (u_long)nval;						\
142 	})
143 
144 /*
145  * Defines for TT-DMA control register
146  */
147 #define	SD_BUSERR	0x80		/* 1 = transfer caused bus error*/
148 #define	SD_ZERO		0x40		/* 1 = byte counter is zero	*/
149 #define	SD_ENABLE	0x02		/* 1 = Enable DMA		*/
150 #define	SD_OUT		0x01		/* Direction: memory to SCSI	*/
151 #define	SD_IN		0x00		/* Direction: SCSI to memory	*/
152 
153 /*
154  * Defines for Hades-DMA control register
155  */
156 #define	SDH_BUSERR	0x02		/* 1 = Bus error		*/
157 #define SDH_EOP		0x01		/* 1 = Signal EOP on 5380	*/
158 #define	SDH_ZERO	0x40		/* 1 = Byte counter is zero	*/
159 
160 /*
161  * Define the 5380 register set
162  */
163 struct scsi_5380 {
164 	volatile u_char	scsi_5380[16];	/* use only the odd bytes	*/
165 };
166 #endif /* TT_SCSI */
167 
168 /**********************************************
169  * Variables present for both TT and Falcon.  *
170  **********************************************/
171 
172 /*
173  * Softc of currently active controller (a bit of fake; we only have one)
174  */
175 static struct ncr_softc	*cur_softc;
176 
177 #if defined(TT_SCSI) && !defined(FALCON_SCSI)
178 /*
179  * We can be more efficient for some functions when only TT_SCSI is selected
180  */
181 #define	GET_5380_REG(rnum)	SCSI_5380->scsi_5380[(rnum << 1) | 1]
182 #define	SET_5380_REG(rnum,val)	(SCSI_5380->scsi_5380[(rnum << 1) | 1] = val)
183 
184 #define scsi_mach_init(sc)	scsi_tt_init(sc)
185 #define scsi_ienable()		scsi_tt_ienable()
186 #define scsi_idisable()		scsi_tt_idisable()
187 #define	scsi_clr_ipend()	scsi_tt_clr_ipend()
188 #define scsi_ipending()		(GET_5380_REG(NCR5380_DMSTAT) & SC_IRQ_SET)
189 #define scsi_dma_setup(r,p,m)	scsi_tt_dmasetup(r, p, m)
190 #define wrong_dma_range(r,d)	tt_wrong_dma_range(r, d)
191 #define poll_edma(reqp)		tt_poll_edma(reqp)
192 #define get_dma_result(r, b)	tt_get_dma_result(r, b)
193 #define	can_access_5380()	1
194 #define emulated_dma()		((machineid & ATARI_HADES) ? 1 : 0)
195 
196 #define fair_to_keep_dma()	1
197 #define claimed_dma()		1
198 #define reconsider_dma()
199 
200 #endif /* defined(TT_SCSI) && !defined(FALCON_SCSI) */
201 
202 #if defined(TT_SCSI)
203 
204 /*
205  * Prototype functions defined below
206  */
207 #ifdef NO_TTRAM_DMA
208 static int tt_wrong_dma_range __P((SC_REQ *, struct dma_chain *));
209 #endif
210 static void	scsi_tt_init __P((struct ncr_softc *));
211 static u_char	get_tt_5380_reg __P((u_short));
212 static void	set_tt_5380_reg __P((u_short, u_short));
213 static void	scsi_tt_dmasetup __P((SC_REQ *, u_int, u_char));
214 static int	tt_poll_edma __P((SC_REQ *));
215 static u_char	*ptov __P((SC_REQ *, u_long*));
216 static int	tt_get_dma_result __P((SC_REQ *, u_long *));
217        void	scsi_tt_ienable __P((void));
218        void	scsi_tt_idisable __P((void));
219        void	scsi_tt_clr_ipend __P((void));
220 
221 /*
222  * Define these too, so we can use them locally...
223  */
224 #define	GET_TT_REG(rnum)	SCSI_5380->scsi_5380[(rnum << 1) | 1]
225 #define	SET_TT_REG(rnum,val)	(SCSI_5380->scsi_5380[(rnum << 1) | 1] = val)
226 
227 #ifdef NO_TTRAM_DMA
228 static int
229 tt_wrong_dma_range(reqp, dm)
230 SC_REQ			*reqp;
231 struct dma_chain	*dm;
232 {
233 	if (dm->dm_addr & 0xff000000) {
234 		reqp->dr_flag |= DRIVER_BOUNCING;
235 		return(1);
236 	}
237 	return(0);
238 }
239 #else
240 #define	tt_wrong_dma_range(reqp, dm)	0
241 #endif
242 
243 static void
244 scsi_tt_init(struct ncr_softc *sc)
245 {
246 	/*
247 	 * Enable SCSI-related interrupts
248 	 */
249 	MFP2->mf_aer  |= 0x80;		/* SCSI IRQ goes HIGH!!!!!	*/
250 
251 	if (machineid & ATARI_TT) {
252 		/* SCSI-dma interrupts		*/
253 		MFP2->mf_ierb |= IB_SCDM;
254 		MFP2->mf_iprb &= ~IB_SCDM;
255 		MFP2->mf_imrb |= IB_SCDM;
256 	}
257 	else if (machineid & ATARI_HADES) {
258 		SCSI_DMA->s_hdma_ctrl = 0;
259 
260 		if (intr_establish(2, AUTO_VEC, 0,
261 					(hw_ifun_t)ncr5380_drq_intr,
262 					NULL) == NULL)
263 		panic("scsi_tt_init: Can't establish drq-interrupt");
264 	}
265 	else panic("scsi_tt_init: should not come here");
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 	 * Remove interrupts already scheduled.
323 	 */
324 	rem_sicallback((si_farg)ncr_ctrl_intr);
325 	rem_sicallback((si_farg)ncr_dma_intr);
326 }
327 
328 static void
329 scsi_tt_dmasetup(SC_REQ *reqp, u_int phase, u_char	mode)
330 {
331 	if (PH_IN(phase)) {
332 		SCSI_DMA->s_dma_ctrl = SD_IN;
333 		if (machineid & ATARI_HADES)
334 		    SCSI_DMA->s_hdma_ctrl &= ~(SDH_BUSERR|SDH_EOP);
335 		set_scsi_dma(&(SCSI_DMA->s_dma_ptr), reqp->dm_cur->dm_addr);
336 		set_scsi_dma(&(SCSI_DMA->s_dma_cnt), reqp->dm_cur->dm_count);
337 		SET_TT_REG(NCR5380_ICOM, 0);
338 		SET_TT_REG(NCR5380_MODE, mode);
339 		SCSI_DMA->s_dma_ctrl = SD_ENABLE;
340 		SET_TT_REG(NCR5380_IRCV, 0);
341 	}
342 	else {
343 		SCSI_DMA->s_dma_ctrl = SD_OUT;
344 		if (machineid & ATARI_HADES)
345 		    SCSI_DMA->s_hdma_ctrl &= ~(SDH_BUSERR|SDH_EOP);
346 		set_scsi_dma(&(SCSI_DMA->s_dma_ptr), reqp->dm_cur->dm_addr);
347 		set_scsi_dma(&(SCSI_DMA->s_dma_cnt), reqp->dm_cur->dm_count);
348 		SET_TT_REG(NCR5380_MODE, mode);
349 		SET_TT_REG(NCR5380_ICOM, SC_ADTB);
350 		SET_TT_REG(NCR5380_DMSTAT, 0);
351 		SCSI_DMA->s_dma_ctrl = SD_ENABLE|SD_OUT;
352 	}
353 }
354 
355 static int
356 tt_poll_edma(SC_REQ *reqp)
357 {
358 	u_char	dmstat, dmastat;
359 	int	timeout = 9000; /* XXX */
360 
361 	/*
362 	 * We wait here until the DMA has finished. This can be
363 	 * achieved by checking the following conditions:
364 	 *   - 5380:
365 	 *	- End of DMA flag is set
366 	 *	- We lost BSY (error!!)
367 	 *	- A phase mismatch has occured (partial transfer)
368 	 *   - DMA-controller:
369 	 *	- A bus error occurred (Kernel error!!)
370 	 *	- All bytes are transferred
371 	 * If one of the terminating conditions was met, we call
372 	 * 'dma_ready' to check errors and perform the bookkeeping.
373 	 */
374 
375 	for (;;) {
376 		delay(20);
377 		if (--timeout <= 0) {
378 			ncr_tprint(reqp, "timeout on polled transfer\n");
379 			reqp->xs->error = XS_TIMEOUT;
380 			return(0);
381 		}
382 		dmstat  = GET_TT_REG(NCR5380_DMSTAT);
383 
384 		if ((machineid & ATARI_HADES) && (dmstat & SC_DMA_REQ)) {
385 			ncr5380_drq_intr();
386 			dmstat  = GET_TT_REG(NCR5380_DMSTAT);
387 		}
388 
389 		dmastat = SCSI_DMA->s_dma_ctrl;
390 		if (dmstat & (SC_END_DMA|SC_BSY_ERR|SC_IRQ_SET))
391 			break;
392 		if (!(dmstat & SC_PHS_MTCH))
393 			break;
394 		if (dmastat & (SD_BUSERR|SD_ZERO))
395 			break;
396 	}
397 	return(1);
398 }
399 
400 /*
401  * Convert physical DMA address to a virtual address.
402  */
403 static u_char *
404 ptov(SC_REQ *reqp, u_long *phaddr)
405 {
406 	struct dma_chain	*dm;
407 	u_char			*vaddr;
408 
409 	dm = reqp->dm_chain;
410 	vaddr = reqp->xdata_ptr;
411 	for(; dm < reqp->dm_cur; dm++)
412 		vaddr += dm->dm_count;
413 	vaddr += (u_long)phaddr - dm->dm_addr;
414 	return(vaddr);
415 }
416 
417 static int
418 tt_get_dma_result(SC_REQ *reqp, u_long *bytes_left)
419 {
420 	int	dmastat, dmstat;
421 	u_char	*byte_p;
422 	u_long	leftover;
423 
424 	dmastat = SCSI_DMA->s_dma_ctrl;
425 	dmstat  = GET_TT_REG(NCR5380_DMSTAT);
426 	get_scsi_dma(SCSI_DMA->s_dma_cnt, leftover);
427 	get_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)byte_p);
428 
429 	if (dmastat & SD_BUSERR) {
430 		/*
431 		 * The DMA-controller seems to access 8 bytes beyond
432 		 * it's limits on output. Therefore check also the byte
433 		 * count. If it's zero, ignore the bus error.
434 		 */
435 		if (leftover != 0) {
436 			ncr_tprint(reqp,
437 				"SCSI-DMA buserror - accessing 0x%x\n", byte_p);
438 			reqp->xs->error = XS_DRIVER_STUFFUP;
439 		}
440 	}
441 
442 	/*
443 	 * We handle the following special condition below:
444 	 *  -- The device disconnects in the middle of a write operation --
445 	 * In this case, the 5380 has already pre-fetched the next byte from
446 	 * the DMA-controller before the phase mismatch occurs. Therefore,
447 	 * leftover is 1 too low.
448 	 * This does not always happen! Therefore, we only do this when
449 	 * leftover is odd. This assumes that DMA transfers are _even_! This
450 	 * is normally the case on disks and types but might not always be.
451 	 * XXX: Check if ACK is consistently high on these occasions LWP
452 	 */
453 	if ((leftover & 1) && !(dmstat & SC_PHS_MTCH) && PH_OUT(reqp->phase))
454 		leftover++;
455 
456 	/*
457 	 * Check if there are some 'restbytes' left in the DMA-controller.
458 	 */
459 	if ((machineid & ATARI_TT) && ((u_long)byte_p & 3)
460 	    && PH_IN(reqp->phase)) {
461 		u_char	*p, *q;
462 
463 		p = ptov(reqp, (u_long *)((u_long)byte_p & ~3));
464 		q = (u_char*)&(SCSI_DMA->s_dma_res);
465 		switch ((u_long)byte_p & 3) {
466 			case 3: *p++ = *q++;
467 			case 2: *p++ = *q++;
468 			case 1: *p++ = *q++;
469 		}
470 	}
471 	*bytes_left = leftover;
472 	return ((dmastat & (SD_BUSERR|SD_ZERO)) ? 1 : 0);
473 }
474 
475 static u_char *dma_ptr;
476 void
477 ncr5380_drq_intr()
478 {
479 extern	int			*nofault;
480 	label_t			faultbuf;
481 	int			write;
482 	u_long	 		count;
483 	u_char			*data_p = (u_char*)(stio_addr+0x741);
484 
485 	/*
486 	 * Block SCSI interrupts while emulating DMA. They come
487 	 * at a higher priority.
488 	 */
489 	single_inst_bclr_b(MFP2->mf_imra, IA_SCSI);
490 
491 	/*
492 	 * Setup for a possible bus error caused by SCSI controller
493 	 * switching out of DATA-IN/OUT before we're done with the
494 	 * current transfer.
495 	 */
496 	nofault = (int *) &faultbuf;
497 
498 	if (setjmp((label_t *) nofault)) {
499 		u_char	*ptr;
500 		u_long	cnt, tmp;
501 
502 		PID("drq berr");
503 		nofault = (int *) 0;
504 
505 		/*
506 		 * Determine number of bytes transferred
507 		 */
508 		get_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)ptr);
509 		cnt = dma_ptr - ptr;
510 
511 		if (cnt != 0) {
512 			/*
513 			 * Update the dma pointer/count fields
514 			 */
515 			set_scsi_dma(SCSI_DMA->s_dma_ptr, dma_ptr);
516 			get_scsi_dma(SCSI_DMA->s_dma_cnt, tmp);
517 			set_scsi_dma(SCSI_DMA->s_dma_cnt, tmp - cnt);
518 
519 			if (tmp > cnt) {
520 				/*
521 				 * Still more to transfer
522 				 */
523 				single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
524 				return;
525 			}
526 
527 			/*
528 			 * Signal EOP to 5380
529 			 */
530 			SCSI_DMA->s_hdma_ctrl |= SDH_EOP;
531 		}
532 		else {
533 			nofault = (int *) &faultbuf;
534 
535 			/*
536 			 * Try to figure out if the byte-count was
537 			 * zero because there was no (more) data or
538 			 * because the dma_ptr is bogus.
539 			 */
540 			if (setjmp((label_t *) nofault)) {
541 				/*
542 				 * Set the bus-error bit
543 				 */
544 				SCSI_DMA->s_hdma_ctrl |= SDH_BUSERR;
545 			}
546 			__asm __volatile ("tstb	%0@(0)": : "a" (dma_ptr));
547 			nofault = (int *)0;
548 		}
549 
550 		/*
551 		 * Schedule an interrupt
552 		 */
553 		if (SCSI_DMA->s_dma_ctrl & SD_ENABLE)
554 		    add_sicallback((si_farg)ncr_dma_intr, (void *)cur_softc, 0);
555 
556 		/*
557 		 * Clear DMA-mode
558 		 */
559 		SCSI_DMA->s_dma_ctrl &= ~SD_ENABLE;
560 		single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
561 
562 		return;
563 	}
564 
565 	write = (SCSI_DMA->s_dma_ctrl & SD_OUT) ? 1 : 0;
566 #if DBG_PID
567 	if (write) {
568 		PID("drq (in)");
569 	} else {
570 		PID("drq (out)");
571 	}
572 #endif
573 
574 	get_scsi_dma(SCSI_DMA->s_dma_cnt, count);
575 	get_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)dma_ptr);
576 
577 	/*
578 	 * Keep pushing bytes until we're done or a bus-error
579 	 * signals that the SCSI controller is not ready.
580 	 * NOTE: I tried some optimalizations in these loops,
581 	 *       but they had no effect on transfer speed.
582 	 */
583 	if (write) {
584 		while(count--) {
585 			*data_p = *dma_ptr++;
586 		}
587 	}
588 	else {
589 		while(count--) {
590 			*dma_ptr++ = *data_p;
591 		}
592 	}
593 
594 	/*
595 	 * Schedule an interrupt
596 	 */
597 	if (SCSI_DMA->s_dma_ctrl & SD_ENABLE)
598 	    add_sicallback((si_farg)ncr_dma_intr, (void *)cur_softc, 0);
599 
600 	/*
601 	 * Clear DMA-mode
602 	 */
603 	SCSI_DMA->s_dma_ctrl &= ~SD_ENABLE;
604 
605 	/*
606 	 * OK.  No bus error occurred above.  Clear the nofault flag
607 	 * so we no longer short-circuit bus errors.
608 	 */
609 	nofault = (int *) 0;
610 
611 	/*
612 	 * Update the DMA 'registers' to reflect that all bytes
613 	 * have been transfered and tell this to the 5380 too.
614 	 */
615 	set_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)dma_ptr);
616 	set_scsi_dma(SCSI_DMA->s_dma_cnt, 0);
617 	SCSI_DMA->s_hdma_ctrl |= SDH_EOP;
618 
619 	PID("end drq");
620 	single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
621 
622 	return;
623 }
624 
625 #endif /* defined(TT_SCSI) */
626 
627 #if defined(FALCON_SCSI) && !defined(TT_SCSI)
628 
629 #define	GET_5380_REG(rnum)	get_falcon_5380_reg(rnum)
630 #define	SET_5380_REG(rnum,val)	set_falcon_5380_reg(rnum, val)
631 #define scsi_mach_init(sc)	scsi_falcon_init(sc)
632 #define scsi_ienable()		scsi_falcon_ienable()
633 #define scsi_idisable()		scsi_falcon_idisable()
634 #define	scsi_clr_ipend()	scsi_falcon_clr_ipend()
635 #define	scsi_ipending()		scsi_falcon_ipending()
636 #define scsi_dma_setup(r,p,m)	scsi_falcon_dmasetup(r, p, m)
637 #define wrong_dma_range(r,d)	falcon_wrong_dma_range(r, d)
638 #define poll_edma(reqp)		falcon_poll_edma(reqp)
639 #define get_dma_result(r, b)	falcon_get_dma_result(r, b)
640 #define	can_access_5380()	falcon_can_access_5380()
641 #define	emulated_dma()		0
642 
643 #define fair_to_keep_dma()	(!st_dmawanted())
644 #define claimed_dma()		falcon_claimed_dma()
645 #define reconsider_dma()	falcon_reconsider_dma()
646 
647 #endif /* defined(FALCON_SCSI) && !defined(TT_SCSI) */
648 
649 #if defined(FALCON_SCSI)
650 
651 /*
652  * Prototype functions defined below
653  */
654 static void	scsi_falcon_init __P((struct ncr_softc *));
655 static u_char	get_falcon_5380_reg __P((u_short));
656 static void	set_falcon_5380_reg __P((u_short, u_short));
657 static int	falcon_wrong_dma_range __P((SC_REQ *, struct dma_chain *));
658 static void	fal1_dma __P((u_int, u_int, SC_REQ *));
659 static void	scsi_falcon_dmasetup __P((SC_REQ  *, u_int, u_char));
660 static int	falcon_poll_edma __P((SC_REQ  *));
661 static int	falcon_get_dma_result __P((SC_REQ  *, u_long *));
662        int	falcon_can_access_5380 __P((void));
663        void	scsi_falcon_clr_ipend __P((void));
664        void	scsi_falcon_idisable __P((void));
665        void	scsi_falcon_ienable __P((void));
666        int	scsi_falcon_ipending __P((void));
667        int	falcon_claimed_dma __P((void));
668        void	falcon_reconsider_dma __P((void));
669 
670 static void
671 scsi_falcon_init(sc)
672 struct ncr_softc	*sc;
673 {
674 	/*
675 	 * Enable disk related interrupts
676 	 */
677 	MFP->mf_ierb  |= IB_DINT;
678 	MFP->mf_iprb  &= ~IB_DINT;
679 	MFP->mf_imrb  |= IB_DINT;
680 }
681 
682 static u_char
683 get_falcon_5380_reg(rnum)
684 u_short	rnum;
685 {
686 	DMA->dma_mode = DMA_SCSI + rnum;
687 	return(DMA->dma_data);
688 }
689 
690 static void
691 set_falcon_5380_reg(rnum, val)
692 u_short	rnum, val;
693 {
694 	DMA->dma_mode = DMA_SCSI + rnum;
695 	DMA->dma_data = val;
696 }
697 
698 extern __inline__ void
699 scsi_falcon_ienable()
700 {
701 	single_inst_bset_b(MFP->mf_imrb, IB_DINT);
702 }
703 
704 extern __inline__ void
705 scsi_falcon_idisable()
706 {
707 	single_inst_bclr_b(MFP->mf_imrb, IB_DINT);
708 }
709 
710 extern __inline__ void
711 scsi_falcon_clr_ipend()
712 {
713 	int	tmp;
714 
715 	tmp = get_falcon_5380_reg(NCR5380_IRCV);
716 	rem_sicallback((si_farg)ncr_ctrl_intr);
717 }
718 
719 extern __inline__ int
720 scsi_falcon_ipending()
721 {
722 	if (connected && (connected->dr_flag & DRIVER_IN_DMA)) {
723 		/*
724 		 *  XXX: When DMA is running, we are only allowed to
725 		 *       check the 5380 when DMA _might_ be finished.
726 		 */
727 		if (MFP->mf_gpip & IO_DINT)
728 		    return (0); /* XXX: Actually: we're not allowed to check */
729 
730 		/* LWP: 28-06, must be a dma interrupt! should the
731 		 * ST-DMA unit be taken out of dma mode?????
732 		 */
733 		DMA->dma_mode = 0x90;
734 
735 	}
736 	return(get_falcon_5380_reg(NCR5380_DMSTAT) & SC_IRQ_SET);
737 }
738 
739 static int
740 falcon_wrong_dma_range(reqp, dm)
741 SC_REQ			*reqp;
742 struct dma_chain	*dm;
743 {
744 	/*
745 	 * Do not allow chains yet! See also comment with
746 	 * falcon_poll_edma() !!!
747 	 */
748 	if (((dm - reqp->dm_chain) > 0) || (dm->dm_addr & 0xff000000)) {
749 		reqp->dr_flag |= DRIVER_BOUNCING;
750 		return(1);
751 	}
752 	/*
753 	 * Never allow DMA to happen on a Falcon when the transfer
754 	 * size is no multiple of 512. This is the transfer unit of the
755 	 * ST DMA-controller.
756 	 */
757 	if(dm->dm_count & 511)
758 		return(1);
759 	return(0);
760 }
761 
762 static	int falcon_lock = 0;
763 
764 extern __inline__ int
765 falcon_claimed_dma()
766 {
767 	if (falcon_lock != DMA_LOCK_GRANT) {
768 		if (falcon_lock == DMA_LOCK_REQ) {
769 			/*
770 			 * DMA access is being claimed.
771 			 */
772 			return(0);
773 		}
774 		if (!st_dmagrab((dma_farg)ncr_ctrl_intr, (dma_farg)run_main,
775 						cur_softc, &falcon_lock, 1))
776 			return(0);
777 	}
778 	return(1);
779 }
780 
781 extern __inline__ void
782 falcon_reconsider_dma()
783 {
784 	if (falcon_lock && (connected == NULL) && (discon_q == NULL)) {
785 		/*
786 		 * No need to keep DMA locked by us as we are not currently
787 		 * connected and no disconnected jobs are pending.
788 		 */
789 		rem_sicallback((si_farg)ncr_ctrl_intr);
790 		st_dmafree(cur_softc, &falcon_lock);
791 	}
792 
793 	if (!falcon_lock && (issue_q != NULL)) {
794 		/*
795 		 * We must (re)claim DMA access as there are jobs
796 		 * waiting in the issue queue.
797 		 */
798 		st_dmagrab((dma_farg)ncr_ctrl_intr, (dma_farg)run_main,
799 						cur_softc, &falcon_lock, 0);
800 	}
801 }
802 
803 static void
804 fal1_dma(dir, nsects, reqp)
805 u_int	dir, nsects;
806 SC_REQ	*reqp;
807 {
808 	dir <<= 8;
809 	st_dmaaddr_set((caddr_t)reqp->dm_cur->dm_addr);
810 	DMA->dma_mode = 0x90 | dir;
811 	DMA->dma_mode = 0x90 | (dir ^ DMA_WRBIT);
812 	DMA->dma_mode = 0x90 | dir;
813 	DMA->dma_data = nsects;
814 	delay(2);	/* _really_ needed (Thomas Gerner) */
815 	DMA->dma_mode = 0x10 | dir;
816 }
817 
818 static void
819 scsi_falcon_dmasetup(reqp, phase, mode)
820 SC_REQ	*reqp;
821 u_int	phase;
822 u_char	mode;
823 {
824 	int	nsects = reqp->dm_cur->dm_count / 512; /* XXX */
825 
826 	/*
827 	 * XXX: We should probably clear the fifo before putting the
828 	 *      5380 into DMA-mode.
829 	 */
830 	if (PH_IN(phase)) {
831 		set_falcon_5380_reg(NCR5380_ICOM, 0);
832 		set_falcon_5380_reg(NCR5380_MODE, mode);
833 		set_falcon_5380_reg(NCR5380_IRCV, 0);
834 		fal1_dma(0, nsects, reqp);
835 	}
836 	else {
837 		set_falcon_5380_reg(NCR5380_MODE, mode);
838 		set_falcon_5380_reg(NCR5380_ICOM, SC_ADTB);
839 		set_falcon_5380_reg(NCR5380_DMSTAT, 0);
840 		fal1_dma(1, nsects, reqp);
841 	}
842 }
843 
844 static int
845 falcon_poll_edma(reqp)
846 SC_REQ	*reqp;
847 {
848 	int	timeout = 9000; /* XXX */
849 
850 	/*
851 	 * Because of the Falcon hardware, it is impossible to reach
852 	 * the 5380 while doing DMA-transfers. So we have to rely on
853 	 * the interrupt line to determine if DMA-has finished. the
854 	 * DMA-controller itself will never fire an interrupt. This means
855 	 * that 'broken-up' DMA transfers are not (yet) possible on the
856 	 * Falcon.
857 	 */
858 	for (;;) {
859 		delay(20);
860 		if (--timeout <= 0) {
861 			ncr_tprint(reqp, "Timeout on polled transfer\n");
862 			reqp->xs->error = XS_TIMEOUT;
863 			return(0);
864 		}
865 		if (!(MFP->mf_gpip & IO_DINT))
866 			break;
867 	}
868 	return(1);
869 }
870 
871 static int
872 falcon_get_dma_result(reqp, bytes_left)
873 SC_REQ	*reqp;
874 u_long	*bytes_left;
875 {
876 	int	rv = 0;
877 	int	st_dmastat;
878 	u_long	bytes_done;
879 
880 	/*
881 	 * Select sector counter register first (See Atari docu.)
882 	 */
883 	DMA->dma_mode = 0x90;
884 	if (!(st_dmastat = DMA->dma_stat) & 0x01) {
885 		/*
886 		 * Misc. DMA-error according to Atari...
887 		 */
888 		ncr_tprint(reqp, "Unknow ST-SCSI error near 0x%x\n",
889 							st_dmaaddr_get());
890 		reqp->xs->error = XS_DRIVER_STUFFUP;
891 		rv = 1;
892 	}
893 	/*
894 	 * Because we NEVER start DMA on the Falcon when the data size
895 	 * is not a multiple of 512 bytes, we can safely round down the
896 	 * byte count on writes. We need to because in case of a disconnect,
897 	 * the DMA has already prefetched the next couple of bytes.
898 	 * On read, these byte counts are an error. They are logged and
899 	 * should be handled by the mi-part of the driver.
900 	 * NOTE: We formerly did this by using the 'byte-count-zero' bit
901 	 *       of the DMA controller, but this didn't seem to work???
902          *       [lwp 29/06/96]
903 	 */
904 	bytes_done = st_dmaaddr_get() - reqp->dm_cur->dm_addr;
905 	if (bytes_done & 511) {
906 		if (PH_IN(reqp->phase)) {
907 			ncr_tprint(reqp, "Byte count on read not a multiple "
908 					 "of 512 (%ld)\n", bytes_done);
909 		}
910 		bytes_done &= ~511;
911 	}
912 	if ((*bytes_left = reqp->dm_cur->dm_count - bytes_done) == 0)
913 		rv = 1;
914 	return(rv);
915 }
916 
917 static int
918 falcon_can_access_5380()
919 {
920 	if (connected && (connected->dr_flag & DRIVER_IN_DMA)
921 		&& (MFP->mf_gpip & IO_DINT))
922 			return(0);
923 	return(1);
924 }
925 
926 #endif /* defined(FALCON_SCSI) */
927 
928 #if defined(TT_SCSI) && defined(FALCON_SCSI)
929 /*
930  * Define some functions to support _both_ TT and Falcon SCSI
931  */
932 
933 /*
934  * The prototypes first...
935  */
936 static void	scsi_mach_init __P((struct ncr_softc *));
937        void	scsi_ienable __P((void));
938        void	scsi_idisable __P((void));
939        void	scsi_clr_ipend __P((void));
940        int	scsi_ipending __P((void));
941        void	scsi_dma_setup __P((SC_REQ *, u_int, u_char));
942        int	wrong_dma_range __P((SC_REQ *, struct dma_chain *));
943        int	poll_edma __P((SC_REQ *));
944        int	get_dma_result __P((SC_REQ *, u_long *));
945        int	can_access_5380 __P((void));
946 
947 /*
948  * Register access will be done through the following 2 function pointers.
949  */
950 static u_char	(*get_5380_reg) __P((u_short));
951 static void	(*set_5380_reg) __P((u_short, u_short));
952 
953 #define	GET_5380_REG	(*get_5380_reg)
954 #define	SET_5380_REG	(*set_5380_reg)
955 
956 static void
957 scsi_mach_init(sc)
958 struct ncr_softc	*sc;
959 {
960 	if (machineid & ATARI_FALCON) {
961 		get_5380_reg = get_falcon_5380_reg;
962 		set_5380_reg = set_falcon_5380_reg;
963 		scsi_falcon_init(sc);
964 	}
965 	else {
966 		get_5380_reg = get_tt_5380_reg;
967 		set_5380_reg = set_tt_5380_reg;
968 		scsi_tt_init(sc);
969 	}
970 }
971 
972 extern __inline__ void
973 scsi_ienable()
974 {
975 	if (machineid & ATARI_FALCON)
976 		scsi_falcon_ienable();
977 	else scsi_tt_ienable();
978 }
979 
980 extern __inline__ void
981 scsi_idisable()
982 {
983 	if (machineid & ATARI_FALCON)
984 		scsi_falcon_idisable();
985 	else scsi_tt_idisable();
986 }
987 
988 extern __inline__ void
989 scsi_clr_ipend()
990 {
991 	if (machineid & ATARI_FALCON)
992 		scsi_falcon_clr_ipend();
993 	else scsi_tt_clr_ipend();
994 }
995 
996 extern __inline__ int
997 scsi_ipending()
998 {
999 	if (machineid & ATARI_FALCON)
1000 		return(scsi_falcon_ipending());
1001 	else return (GET_TT_REG(NCR5380_DMSTAT) & SC_IRQ_SET);
1002 }
1003 
1004 extern __inline__ void
1005 scsi_dma_setup(reqp, phase, mbase)
1006 SC_REQ	*reqp;
1007 u_int	phase;
1008 u_char	mbase;
1009 {
1010 	if (machineid & ATARI_FALCON)
1011 		scsi_falcon_dmasetup(reqp, phase, mbase);
1012 	else scsi_tt_dmasetup(reqp, phase, mbase);
1013 }
1014 
1015 extern __inline__ int
1016 wrong_dma_range(reqp, dm)
1017 SC_REQ			*reqp;
1018 struct dma_chain	*dm;
1019 {
1020 	if (machineid & ATARI_FALCON)
1021 		return(falcon_wrong_dma_range(reqp, dm));
1022 	else return(tt_wrong_dma_range(reqp, dm));
1023 }
1024 
1025 extern __inline__ int
1026 poll_edma(reqp)
1027 SC_REQ	*reqp;
1028 {
1029 	if (machineid & ATARI_FALCON)
1030 		return(falcon_poll_edma(reqp));
1031 	else return(tt_poll_edma(reqp));
1032 }
1033 
1034 extern __inline__ int
1035 get_dma_result(reqp, bytes_left)
1036 SC_REQ	*reqp;
1037 u_long	*bytes_left;
1038 {
1039 	if (machineid & ATARI_FALCON)
1040 		return(falcon_get_dma_result(reqp, bytes_left));
1041 	else return(tt_get_dma_result(reqp, bytes_left));
1042 }
1043 
1044 extern __inline__ int
1045 can_access_5380()
1046 {
1047 	if (machineid & ATARI_FALCON)
1048 		return(falcon_can_access_5380());
1049 	return(1);
1050 }
1051 
1052 #define emulated_dma()		((machineid & ATARI_HADES) ? 1 : 0)
1053 
1054 /*
1055  * Locking stuff. All turns into NOP's on the TT.
1056  */
1057 #define	fair_to_keep_dma()	((machineid & ATARI_FALCON) ?		\
1058 						!st_dmawanted() : 1)
1059 #define	claimed_dma()		((machineid & ATARI_FALCON) ?		\
1060 						falcon_claimed_dma() : 1)
1061 #define reconsider_dma()	{					\
1062 					if(machineid & ATARI_FALCON)	\
1063 						falcon_reconsider_dma();\
1064 				}
1065 #endif /* defined(TT_SCSI) && defined(FALCON_SCSI) */
1066 
1067 /**********************************************
1068  * Functions present for both TT and Falcon.  *
1069  **********************************************/
1070 /*
1071  * Our autoconfig matching function
1072  */
1073 static int
1074 machine_match(struct device *pdp, void *match, void *auxp,
1075 						struct cfdriver *cd)
1076 {
1077 	struct cfdata *cdp = match;
1078 
1079 	if (strcmp(auxp, cd->cd_name))
1080 		return(0);
1081 	if (cdp->cf_unit != 0)	/* Only one unit	*/
1082 		return(0);
1083 	return(1);
1084 }
1085 
1086 /*
1087  * Bounce buffer (de)allocation. Those buffers are gotten from the ST-mem
1088  * pool. Allocation here is both contiguous and in the lower 16Mb of
1089  * the address space. Thus being DMA-able for all controllers.
1090  */
1091 static u_char *
1092 alloc_bounceb(u_long len)
1093 {
1094 	void	*tmp;
1095 
1096 	return((u_char *)alloc_stmem(len, &tmp));
1097 }
1098 
1099 static void
1100 free_bounceb(u_char *bounceb)
1101 {
1102 	free_stmem(bounceb);
1103 }
1104 
1105 /*
1106  * 5380 interrupt.
1107  */
1108 void
1109 scsi_ctrl(int sr)
1110 {
1111 	if (GET_5380_REG(NCR5380_DMSTAT) & SC_IRQ_SET) {
1112 		scsi_idisable();
1113 		if (!BASEPRI(sr))
1114 			add_sicallback((si_farg)ncr_ctrl_intr,
1115 						(void *)cur_softc, 0);
1116 		else {
1117 			spl1();
1118 			ncr_ctrl_intr(cur_softc);
1119 			spl0();
1120 		}
1121 	}
1122 }
1123 
1124 /*
1125  * DMA controller interrupt
1126  */
1127 void
1128 scsi_dma(int sr)
1129 {
1130 	SC_REQ	*reqp;
1131 
1132 	if ((reqp = connected) && (reqp->dr_flag & DRIVER_IN_DMA)) {
1133 		scsi_idisable();
1134 		if (!BASEPRI(sr))
1135 			add_sicallback((si_farg)ncr_dma_intr,
1136 					(void *)cur_softc, 0);
1137 		else {
1138 			spl1();
1139 			ncr_dma_intr(cur_softc);
1140 			spl0();
1141 		}
1142 	}
1143 }
1144 
1145 /*
1146  * Last but not least... Include the general driver code
1147  */
1148 #include <atari/dev/ncr5380.c>
1149