xref: /netbsd-src/sys/arch/atari/dev/atari5380.c (revision fdecd6a253f999ae92b139670d9e15cc9df4497c)
1 /*	$NetBSD: atari5380.c,v 1.26 1997/06/04 14:34:03 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 #include <m68k/cpu.h>
44 #include <m68k/cacheops.h>
45 
46 #include <atari/atari/stalloc.h>
47 
48 /*
49  * Include the driver definitions
50  */
51 #include <atari/dev/ncr5380reg.h>
52 
53 #include <machine/stdarg.h>
54 #include <machine/iomap.h>
55 #include <machine/mfp.h>
56 
57 #include <atari/atari/intr.h>
58 
59 #if defined(FALCON_SCSI)
60 #include <machine/dma.h>
61 #endif
62 
63 /*
64  * Set the various driver options
65  */
66 #define	NREQ		18	/* Size of issue queue			*/
67 #define	AUTO_SENSE	1	/* Automatically issue a request-sense 	*/
68 
69 #define	DRNAME		ncrscsi	/* used in various prints		*/
70 #undef	DBG_SEL			/* Show the selection process		*/
71 #undef	DBG_REQ			/* Show enqueued/ready requests		*/
72 #undef	DBG_ERR_RET		/* Show requests with != 0 return code	*/
73 #undef	DBG_NOWRITE		/* Do not allow writes to the targets	*/
74 #undef	DBG_PIO			/* Show the polled-I/O process		*/
75 #undef	DBG_INF			/* Show information transfer process	*/
76 #define	DBG_NOSTATIC		/* No static functions, all in DDB trace*/
77 #define	DBG_PID		15	/* Keep track of driver			*/
78 #define	REAL_DMA		/* Use DMA if sensible			*/
79 #if defined(FALCON_SCSI)
80 #define	REAL_DMA_POLL	1	/* 1: Poll for end of DMA-transfer	*/
81 #else
82 #define	REAL_DMA_POLL	0	/* 1: Poll for end of DMA-transfer	*/
83 #endif
84 #undef	USE_PDMA		/* Use special pdma-transfer function	*/
85 #define MIN_PHYS	65536	/*BARF!!!!*/
86 
87 /*
88  * Include more driver definitions
89  */
90 #include <atari/dev/ncr5380var.h>
91 
92 /*
93  * The atari specific driver options
94  */
95 #undef	NO_TTRAM_DMA		/* Do not use DMA to TT-ram. This	*/
96 				/*    fails on older atari's		*/
97 #define	ENABLE_NCR5380(sc)	cur_softc = sc;
98 
99 static u_char	*alloc_bounceb __P((u_long));
100 static void	free_bounceb __P((u_char *));
101 static int	machine_match __P((struct device *, void *, void *,
102 							struct cfdriver *));
103        void	scsi_ctrl __P((int));
104        void	scsi_dma __P((int));
105 
106 /*
107  * Functions that do nothing on the atari
108  */
109 #define	pdma_ready()		0
110 
111 #if defined(TT_SCSI)
112 
113 void	ncr5380_drq_intr __P((void));
114 
115 /*
116  * Define all the things we need of the DMA-controller
117  */
118 #define	SCSI_DMA	((struct scsi_dma *)AD_SCSI_DMA)
119 #define	SCSI_5380	((struct scsi_5380 *)AD_NCR5380)
120 
121 struct scsi_dma {
122 	volatile u_char		s_dma_ptr[8];	/* use only the odd bytes */
123 	volatile u_char		s_dma_cnt[8];	/* use only the odd bytes */
124 	volatile u_char		s_dma_res[4];	/* data residue register  */
125 	volatile u_char		s_dma_gap;	/* not used		  */
126 	volatile u_char		s_dma_ctrl;	/* control register	  */
127 	volatile u_char		s_dma_gap2;	/* not used		  */
128 	volatile u_char		s_hdma_ctrl;	/* Hades control register */
129 };
130 
131 #define	set_scsi_dma(addr, val)	(void)(					\
132 	{								\
133 	u_char	*address = (u_char*)addr+1;				\
134 	u_long	nval	 = (u_long)val;					\
135 	__asm("movepl	%0, %1@(0)": :"d" (nval), "a" (address));	\
136 	})
137 
138 #define	get_scsi_dma(addr, res)	(					\
139 	{								\
140 	u_char	*address = (u_char*)addr+1;				\
141 	u_long	nval;							\
142 	__asm("movepl	%1@(0), %0": "=d" (nval) : "a" (address));	\
143 	res = (u_long)nval;						\
144 	})
145 
146 /*
147  * Defines for TT-DMA control register
148  */
149 #define	SD_BUSERR	0x80		/* 1 = transfer caused bus error*/
150 #define	SD_ZERO		0x40		/* 1 = byte counter is zero	*/
151 #define	SD_ENABLE	0x02		/* 1 = Enable DMA		*/
152 #define	SD_OUT		0x01		/* Direction: memory to SCSI	*/
153 #define	SD_IN		0x00		/* Direction: SCSI to memory	*/
154 
155 /*
156  * Defines for Hades-DMA control register
157  */
158 #define	SDH_BUSERR	0x02		/* 1 = Bus error		*/
159 #define SDH_EOP		0x01		/* 1 = Signal EOP on 5380	*/
160 #define	SDH_ZERO	0x40		/* 1 = Byte counter is zero	*/
161 
162 /*
163  * Define the 5380 register set
164  */
165 struct scsi_5380 {
166 	volatile u_char	scsi_5380[16];	/* use only the odd bytes	*/
167 };
168 #endif /* TT_SCSI */
169 
170 /**********************************************
171  * Variables present for both TT and Falcon.  *
172  **********************************************/
173 
174 /*
175  * Softc of currently active controller (a bit of fake; we only have one)
176  */
177 static struct ncr_softc	*cur_softc;
178 
179 #if defined(TT_SCSI) && !defined(FALCON_SCSI)
180 /*
181  * We can be more efficient for some functions when only TT_SCSI is selected
182  */
183 #define	GET_5380_REG(rnum)	SCSI_5380->scsi_5380[(rnum << 1) | 1]
184 #define	SET_5380_REG(rnum,val)	(SCSI_5380->scsi_5380[(rnum << 1) | 1] = val)
185 
186 #define scsi_mach_init(sc)	scsi_tt_init(sc)
187 #define scsi_ienable()		scsi_tt_ienable()
188 #define scsi_idisable()		scsi_tt_idisable()
189 #define	scsi_clr_ipend()	scsi_tt_clr_ipend()
190 #define scsi_ipending()		(GET_5380_REG(NCR5380_DMSTAT) & SC_IRQ_SET)
191 #define scsi_dma_setup(r,p,m)	scsi_tt_dmasetup(r, p, m)
192 #define wrong_dma_range(r,d)	tt_wrong_dma_range(r, d)
193 #define poll_edma(reqp)		tt_poll_edma(reqp)
194 #define get_dma_result(r, b)	tt_get_dma_result(r, b)
195 #define	can_access_5380()	1
196 #define emulated_dma()		((machineid & ATARI_HADES) ? 1 : 0)
197 
198 #define fair_to_keep_dma()	1
199 #define claimed_dma()		1
200 #define reconsider_dma()
201 
202 #endif /* defined(TT_SCSI) && !defined(FALCON_SCSI) */
203 
204 #if defined(TT_SCSI)
205 
206 /*
207  * Prototype functions defined below
208  */
209 #ifdef NO_TTRAM_DMA
210 static int tt_wrong_dma_range __P((SC_REQ *, struct dma_chain *));
211 #endif
212 static void	scsi_tt_init __P((struct ncr_softc *));
213 static u_char	get_tt_5380_reg __P((u_short));
214 static void	set_tt_5380_reg __P((u_short, u_short));
215 static void	scsi_tt_dmasetup __P((SC_REQ *, u_int, u_char));
216 static int	tt_poll_edma __P((SC_REQ *));
217 static u_char	*ptov __P((SC_REQ *, u_long*));
218 static int	tt_get_dma_result __P((SC_REQ *, u_long *));
219        void	scsi_tt_ienable __P((void));
220        void	scsi_tt_idisable __P((void));
221        void	scsi_tt_clr_ipend __P((void));
222 
223 /*
224  * Define these too, so we can use them locally...
225  */
226 #define	GET_TT_REG(rnum)	SCSI_5380->scsi_5380[(rnum << 1) | 1]
227 #define	SET_TT_REG(rnum,val)	(SCSI_5380->scsi_5380[(rnum << 1) | 1] = val)
228 
229 #ifdef NO_TTRAM_DMA
230 static int
231 tt_wrong_dma_range(reqp, dm)
232 SC_REQ			*reqp;
233 struct dma_chain	*dm;
234 {
235 	if (dm->dm_addr & 0xff000000) {
236 		reqp->dr_flag |= DRIVER_BOUNCING;
237 		return(1);
238 	}
239 	return(0);
240 }
241 #else
242 #define	tt_wrong_dma_range(reqp, dm)	0
243 #endif
244 
245 static void
246 scsi_tt_init(struct ncr_softc *sc)
247 {
248 	/*
249 	 * Enable SCSI-related interrupts
250 	 */
251 	MFP2->mf_aer  |= 0x80;		/* SCSI IRQ goes HIGH!!!!!	*/
252 
253 	if (machineid & ATARI_TT) {
254 		/* SCSI-dma interrupts		*/
255 		MFP2->mf_ierb |= IB_SCDM;
256 		MFP2->mf_iprb &= ~IB_SCDM;
257 		MFP2->mf_imrb |= IB_SCDM;
258 	}
259 	else if (machineid & ATARI_HADES) {
260 		SCSI_DMA->s_hdma_ctrl = 0;
261 
262 		if (intr_establish(2, AUTO_VEC, 0,
263 					(hw_ifun_t)ncr5380_drq_intr,
264 					NULL) == NULL)
265 		panic("scsi_tt_init: Can't establish drq-interrupt");
266 	}
267 	else panic("scsi_tt_init: should not come here");
268 
269 	MFP2->mf_iera |= IA_SCSI;	/* SCSI-5380 interrupts		*/
270 	MFP2->mf_ipra &= ~IA_SCSI;
271 	MFP2->mf_imra |= IA_SCSI;
272 
273 	/*
274 	 * LWP: DMA transfers to TT-ram causes data to be garbeled
275 	 * without notice on some revisons of the TT-mainboard.
276 	 * When program's generate misterious Segmentations faults,
277 	 * try turning on NO_TTRAM_DMA.
278 	 */
279 #ifdef NO_TTRAM_DMA
280 	printf(": DMA to TT-RAM is disabled!");
281 #endif
282 }
283 
284 static u_char
285 get_tt_5380_reg(u_short rnum)
286 {
287 	return(SCSI_5380->scsi_5380[(rnum << 1) | 1]);
288 }
289 
290 static void
291 set_tt_5380_reg(u_short rnum, u_short val)
292 {
293 	SCSI_5380->scsi_5380[(rnum << 1) | 1] = val;
294 }
295 
296 extern __inline__ void
297 scsi_tt_ienable(void)
298 {
299 	if (machineid & ATARI_TT)
300 		single_inst_bset_b(MFP2->mf_imrb, IB_SCDM);
301 	single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
302 }
303 
304 extern __inline__ void
305 scsi_tt_idisable(void)
306 {
307 	if (machineid & ATARI_TT)
308 		single_inst_bclr_b(MFP2->mf_imrb, IB_SCDM);
309 	single_inst_bclr_b(MFP2->mf_imra, IA_SCSI);
310 }
311 
312 extern __inline__ void
313 scsi_tt_clr_ipend(void)
314 {
315 	int	tmp;
316 
317 	SCSI_DMA->s_dma_ctrl = 0;
318 	tmp = GET_TT_REG(NCR5380_IRCV);
319 	if (machineid & ATARI_TT)
320 		single_inst_bclr_b(MFP2->mf_iprb, IB_SCDM);
321 	single_inst_bclr_b(MFP2->mf_ipra, IA_SCSI);
322 
323 	/*
324 	 * Remove interrupts already scheduled.
325 	 */
326 	rem_sicallback((si_farg)ncr_ctrl_intr);
327 	rem_sicallback((si_farg)ncr_dma_intr);
328 }
329 
330 static void
331 scsi_tt_dmasetup(SC_REQ *reqp, u_int phase, u_char	mode)
332 {
333 	if (PH_IN(phase)) {
334 		SCSI_DMA->s_dma_ctrl = SD_IN;
335 		if (machineid & ATARI_HADES)
336 		    SCSI_DMA->s_hdma_ctrl &= ~(SDH_BUSERR|SDH_EOP);
337 		set_scsi_dma(&(SCSI_DMA->s_dma_ptr), reqp->dm_cur->dm_addr);
338 		set_scsi_dma(&(SCSI_DMA->s_dma_cnt), reqp->dm_cur->dm_count);
339 		SET_TT_REG(NCR5380_ICOM, 0);
340 		SET_TT_REG(NCR5380_MODE, mode);
341 		SCSI_DMA->s_dma_ctrl = SD_ENABLE;
342 		SET_TT_REG(NCR5380_IRCV, 0);
343 	}
344 	else {
345 		SCSI_DMA->s_dma_ctrl = SD_OUT;
346 		if (machineid & ATARI_HADES)
347 		    SCSI_DMA->s_hdma_ctrl &= ~(SDH_BUSERR|SDH_EOP);
348 		set_scsi_dma(&(SCSI_DMA->s_dma_ptr), reqp->dm_cur->dm_addr);
349 		set_scsi_dma(&(SCSI_DMA->s_dma_cnt), reqp->dm_cur->dm_count);
350 		SET_TT_REG(NCR5380_MODE, mode);
351 		SET_TT_REG(NCR5380_ICOM, SC_ADTB);
352 		SET_TT_REG(NCR5380_DMSTAT, 0);
353 		SCSI_DMA->s_dma_ctrl = SD_ENABLE|SD_OUT;
354 	}
355 }
356 
357 static int
358 tt_poll_edma(SC_REQ *reqp)
359 {
360 	u_char	dmstat, dmastat;
361 	int	timeout = 9000; /* XXX */
362 
363 	/*
364 	 * We wait here until the DMA has finished. This can be
365 	 * achieved by checking the following conditions:
366 	 *   - 5380:
367 	 *	- End of DMA flag is set
368 	 *	- We lost BSY (error!!)
369 	 *	- A phase mismatch has occured (partial transfer)
370 	 *   - DMA-controller:
371 	 *	- A bus error occurred (Kernel error!!)
372 	 *	- All bytes are transferred
373 	 * If one of the terminating conditions was met, we call
374 	 * 'dma_ready' to check errors and perform the bookkeeping.
375 	 */
376 
377 	for (;;) {
378 		delay(20);
379 		if (--timeout <= 0) {
380 			ncr_tprint(reqp, "timeout on polled transfer\n");
381 			reqp->xs->error = XS_TIMEOUT;
382 			return(0);
383 		}
384 		dmstat  = GET_TT_REG(NCR5380_DMSTAT);
385 
386 		if ((machineid & ATARI_HADES) && (dmstat & SC_DMA_REQ)) {
387 			ncr5380_drq_intr();
388 			dmstat  = GET_TT_REG(NCR5380_DMSTAT);
389 		}
390 
391 		dmastat = SCSI_DMA->s_dma_ctrl;
392 		if (dmstat & (SC_END_DMA|SC_BSY_ERR|SC_IRQ_SET))
393 			break;
394 		if (!(dmstat & SC_PHS_MTCH))
395 			break;
396 		if (dmastat & (SD_BUSERR|SD_ZERO))
397 			break;
398 	}
399 	return(1);
400 }
401 
402 /*
403  * Convert physical DMA address to a virtual address.
404  */
405 static u_char *
406 ptov(SC_REQ *reqp, u_long *phaddr)
407 {
408 	struct dma_chain	*dm;
409 	u_char			*vaddr;
410 
411 	dm = reqp->dm_chain;
412 	vaddr = reqp->xdata_ptr;
413 	for(; dm < reqp->dm_cur; dm++)
414 		vaddr += dm->dm_count;
415 	vaddr += (u_long)phaddr - dm->dm_addr;
416 	return(vaddr);
417 }
418 
419 static int
420 tt_get_dma_result(SC_REQ *reqp, u_long *bytes_left)
421 {
422 	int	dmastat, dmstat;
423 	u_char	*byte_p;
424 	u_long	leftover;
425 
426 	dmastat = SCSI_DMA->s_dma_ctrl;
427 	dmstat  = GET_TT_REG(NCR5380_DMSTAT);
428 	get_scsi_dma(SCSI_DMA->s_dma_cnt, leftover);
429 	get_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)byte_p);
430 
431 	if (dmastat & SD_BUSERR) {
432 		/*
433 		 * The DMA-controller seems to access 8 bytes beyond
434 		 * it's limits on output. Therefore check also the byte
435 		 * count. If it's zero, ignore the bus error.
436 		 */
437 		if (leftover != 0) {
438 			ncr_tprint(reqp,
439 				"SCSI-DMA buserror - accessing 0x%x\n", byte_p);
440 			reqp->xs->error = XS_DRIVER_STUFFUP;
441 		}
442 	}
443 
444 	/*
445 	 * We handle the following special condition below:
446 	 *  -- The device disconnects in the middle of a write operation --
447 	 * In this case, the 5380 has already pre-fetched the next byte from
448 	 * the DMA-controller before the phase mismatch occurs. Therefore,
449 	 * leftover is 1 too low.
450 	 * This does not always happen! Therefore, we only do this when
451 	 * leftover is odd. This assumes that DMA transfers are _even_! This
452 	 * is normally the case on disks and types but might not always be.
453 	 * XXX: Check if ACK is consistently high on these occasions LWP
454 	 */
455 	if ((leftover & 1) && !(dmstat & SC_PHS_MTCH) && PH_OUT(reqp->phase))
456 		leftover++;
457 
458 	/*
459 	 * Check if there are some 'restbytes' left in the DMA-controller.
460 	 */
461 	if ((machineid & ATARI_TT) && ((u_long)byte_p & 3)
462 	    && PH_IN(reqp->phase)) {
463 		u_char	*p, *q;
464 
465 		p = ptov(reqp, (u_long *)((u_long)byte_p & ~3));
466 		q = (u_char*)&(SCSI_DMA->s_dma_res);
467 		switch ((u_long)byte_p & 3) {
468 			case 3: *p++ = *q++;
469 			case 2: *p++ = *q++;
470 			case 1: *p++ = *q++;
471 		}
472 	}
473 	*bytes_left = leftover;
474 	return ((dmastat & (SD_BUSERR|SD_ZERO)) ? 1 : 0);
475 }
476 
477 static u_char *dma_ptr;
478 void
479 ncr5380_drq_intr()
480 {
481 extern	int			*nofault;
482 	label_t			faultbuf;
483 	int			write;
484 	u_long	 		count;
485 	u_char			*data_p = (u_char*)(stio_addr+0x741);
486 
487 	/*
488 	 * Block SCSI interrupts while emulating DMA. They come
489 	 * at a higher priority.
490 	 */
491 	single_inst_bclr_b(MFP2->mf_imra, IA_SCSI);
492 
493 	/*
494 	 * Setup for a possible bus error caused by SCSI controller
495 	 * switching out of DATA-IN/OUT before we're done with the
496 	 * current transfer.
497 	 */
498 	nofault = (int *) &faultbuf;
499 
500 	if (setjmp((label_t *) nofault)) {
501 		u_char	*ptr;
502 		u_long	cnt, tmp;
503 
504 		PID("drq berr");
505 		nofault = (int *) 0;
506 
507 		/*
508 		 * Determine number of bytes transferred
509 		 */
510 		get_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)ptr);
511 		cnt = dma_ptr - ptr;
512 
513 		if (cnt != 0) {
514 			/*
515 			 * Update the dma pointer/count fields
516 			 */
517 			set_scsi_dma(SCSI_DMA->s_dma_ptr, dma_ptr);
518 			get_scsi_dma(SCSI_DMA->s_dma_cnt, tmp);
519 			set_scsi_dma(SCSI_DMA->s_dma_cnt, tmp - cnt);
520 
521 			if (tmp > cnt) {
522 				/*
523 				 * Still more to transfer
524 				 */
525 				single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
526 				return;
527 			}
528 
529 			/*
530 			 * Signal EOP to 5380
531 			 */
532 			SCSI_DMA->s_hdma_ctrl |= SDH_EOP;
533 		}
534 		else {
535 			nofault = (int *) &faultbuf;
536 
537 			/*
538 			 * Try to figure out if the byte-count was
539 			 * zero because there was no (more) data or
540 			 * because the dma_ptr is bogus.
541 			 */
542 			if (setjmp((label_t *) nofault)) {
543 				/*
544 				 * Set the bus-error bit
545 				 */
546 				SCSI_DMA->s_hdma_ctrl |= SDH_BUSERR;
547 			}
548 			__asm __volatile ("tstb	%0@(0)": : "a" (dma_ptr));
549 			nofault = (int *)0;
550 		}
551 
552 		/*
553 		 * Schedule an interrupt
554 		 */
555 		if (SCSI_DMA->s_dma_ctrl & SD_ENABLE)
556 		    add_sicallback((si_farg)ncr_dma_intr, (void *)cur_softc, 0);
557 
558 		/*
559 		 * Clear DMA-mode
560 		 */
561 		SCSI_DMA->s_dma_ctrl &= ~SD_ENABLE;
562 		single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
563 
564 		return;
565 	}
566 
567 	write = (SCSI_DMA->s_dma_ctrl & SD_OUT) ? 1 : 0;
568 #if DBG_PID
569 	if (write) {
570 		PID("drq (in)");
571 	} else {
572 		PID("drq (out)");
573 	}
574 #endif
575 
576 	get_scsi_dma(SCSI_DMA->s_dma_cnt, count);
577 	get_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)dma_ptr);
578 
579 	/*
580 	 * Keep pushing bytes until we're done or a bus-error
581 	 * signals that the SCSI controller is not ready.
582 	 * NOTE: I tried some optimalizations in these loops,
583 	 *       but they had no effect on transfer speed.
584 	 */
585 	if (write) {
586 		while(count--) {
587 			*data_p = *dma_ptr++;
588 		}
589 	}
590 	else {
591 		while(count--) {
592 			*dma_ptr++ = *data_p;
593 		}
594 	}
595 
596 	/*
597 	 * Schedule an interrupt
598 	 */
599 	if (SCSI_DMA->s_dma_ctrl & SD_ENABLE)
600 	    add_sicallback((si_farg)ncr_dma_intr, (void *)cur_softc, 0);
601 
602 	/*
603 	 * Clear DMA-mode
604 	 */
605 	SCSI_DMA->s_dma_ctrl &= ~SD_ENABLE;
606 
607 	/*
608 	 * OK.  No bus error occurred above.  Clear the nofault flag
609 	 * so we no longer short-circuit bus errors.
610 	 */
611 	nofault = (int *) 0;
612 
613 	/*
614 	 * Update the DMA 'registers' to reflect that all bytes
615 	 * have been transfered and tell this to the 5380 too.
616 	 */
617 	set_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)dma_ptr);
618 	set_scsi_dma(SCSI_DMA->s_dma_cnt, 0);
619 	SCSI_DMA->s_hdma_ctrl |= SDH_EOP;
620 
621 	PID("end drq");
622 	single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
623 
624 	return;
625 }
626 
627 #endif /* defined(TT_SCSI) */
628 
629 #if defined(FALCON_SCSI) && !defined(TT_SCSI)
630 
631 #define	GET_5380_REG(rnum)	get_falcon_5380_reg(rnum)
632 #define	SET_5380_REG(rnum,val)	set_falcon_5380_reg(rnum, val)
633 #define scsi_mach_init(sc)	scsi_falcon_init(sc)
634 #define scsi_ienable()		scsi_falcon_ienable()
635 #define scsi_idisable()		scsi_falcon_idisable()
636 #define	scsi_clr_ipend()	scsi_falcon_clr_ipend()
637 #define	scsi_ipending()		scsi_falcon_ipending()
638 #define scsi_dma_setup(r,p,m)	scsi_falcon_dmasetup(r, p, m)
639 #define wrong_dma_range(r,d)	falcon_wrong_dma_range(r, d)
640 #define poll_edma(reqp)		falcon_poll_edma(reqp)
641 #define get_dma_result(r, b)	falcon_get_dma_result(r, b)
642 #define	can_access_5380()	falcon_can_access_5380()
643 #define	emulated_dma()		0
644 
645 #define fair_to_keep_dma()	(!st_dmawanted())
646 #define claimed_dma()		falcon_claimed_dma()
647 #define reconsider_dma()	falcon_reconsider_dma()
648 
649 #endif /* defined(FALCON_SCSI) && !defined(TT_SCSI) */
650 
651 #if defined(FALCON_SCSI)
652 
653 /*
654  * Prototype functions defined below
655  */
656 static void	scsi_falcon_init __P((struct ncr_softc *));
657 static u_char	get_falcon_5380_reg __P((u_short));
658 static void	set_falcon_5380_reg __P((u_short, u_short));
659 static int	falcon_wrong_dma_range __P((SC_REQ *, struct dma_chain *));
660 static void	fal1_dma __P((u_int, u_int, SC_REQ *));
661 static void	scsi_falcon_dmasetup __P((SC_REQ  *, u_int, u_char));
662 static int	falcon_poll_edma __P((SC_REQ  *));
663 static int	falcon_get_dma_result __P((SC_REQ  *, u_long *));
664        int	falcon_can_access_5380 __P((void));
665        void	scsi_falcon_clr_ipend __P((void));
666        void	scsi_falcon_idisable __P((void));
667        void	scsi_falcon_ienable __P((void));
668        int	scsi_falcon_ipending __P((void));
669        int	falcon_claimed_dma __P((void));
670        void	falcon_reconsider_dma __P((void));
671 
672 static void
673 scsi_falcon_init(sc)
674 struct ncr_softc	*sc;
675 {
676 	/*
677 	 * Enable disk related interrupts
678 	 */
679 	MFP->mf_ierb  |= IB_DINT;
680 	MFP->mf_iprb  &= ~IB_DINT;
681 	MFP->mf_imrb  |= IB_DINT;
682 }
683 
684 static u_char
685 get_falcon_5380_reg(rnum)
686 u_short	rnum;
687 {
688 	DMA->dma_mode = DMA_SCSI + rnum;
689 	return(DMA->dma_data);
690 }
691 
692 static void
693 set_falcon_5380_reg(rnum, val)
694 u_short	rnum, val;
695 {
696 	DMA->dma_mode = DMA_SCSI + rnum;
697 	DMA->dma_data = val;
698 }
699 
700 extern __inline__ void
701 scsi_falcon_ienable()
702 {
703 	single_inst_bset_b(MFP->mf_imrb, IB_DINT);
704 }
705 
706 extern __inline__ void
707 scsi_falcon_idisable()
708 {
709 	single_inst_bclr_b(MFP->mf_imrb, IB_DINT);
710 }
711 
712 extern __inline__ void
713 scsi_falcon_clr_ipend()
714 {
715 	int	tmp;
716 
717 	tmp = get_falcon_5380_reg(NCR5380_IRCV);
718 	rem_sicallback((si_farg)ncr_ctrl_intr);
719 }
720 
721 extern __inline__ int
722 scsi_falcon_ipending()
723 {
724 	if (connected && (connected->dr_flag & DRIVER_IN_DMA)) {
725 		/*
726 		 *  XXX: When DMA is running, we are only allowed to
727 		 *       check the 5380 when DMA _might_ be finished.
728 		 */
729 		if (MFP->mf_gpip & IO_DINT)
730 		    return (0); /* XXX: Actually: we're not allowed to check */
731 
732 		/* LWP: 28-06, must be a dma interrupt! should the
733 		 * ST-DMA unit be taken out of dma mode?????
734 		 */
735 		DMA->dma_mode = 0x90;
736 
737 	}
738 	return(get_falcon_5380_reg(NCR5380_DMSTAT) & SC_IRQ_SET);
739 }
740 
741 static int
742 falcon_wrong_dma_range(reqp, dm)
743 SC_REQ			*reqp;
744 struct dma_chain	*dm;
745 {
746 	/*
747 	 * Do not allow chains yet! See also comment with
748 	 * falcon_poll_edma() !!!
749 	 */
750 	if (((dm - reqp->dm_chain) > 0) || (dm->dm_addr & 0xff000000)) {
751 		reqp->dr_flag |= DRIVER_BOUNCING;
752 		return(1);
753 	}
754 	/*
755 	 * Never allow DMA to happen on a Falcon when the transfer
756 	 * size is no multiple of 512. This is the transfer unit of the
757 	 * ST DMA-controller.
758 	 */
759 	if(dm->dm_count & 511)
760 		return(1);
761 	return(0);
762 }
763 
764 static	int falcon_lock = 0;
765 
766 extern __inline__ int
767 falcon_claimed_dma()
768 {
769 	if (falcon_lock != DMA_LOCK_GRANT) {
770 		if (falcon_lock == DMA_LOCK_REQ) {
771 			/*
772 			 * DMA access is being claimed.
773 			 */
774 			return(0);
775 		}
776 		if (!st_dmagrab((dma_farg)ncr_ctrl_intr, (dma_farg)run_main,
777 						cur_softc, &falcon_lock, 1))
778 			return(0);
779 	}
780 	return(1);
781 }
782 
783 extern __inline__ void
784 falcon_reconsider_dma()
785 {
786 	if (falcon_lock && (connected == NULL) && (discon_q == NULL)) {
787 		/*
788 		 * No need to keep DMA locked by us as we are not currently
789 		 * connected and no disconnected jobs are pending.
790 		 */
791 		rem_sicallback((si_farg)ncr_ctrl_intr);
792 		st_dmafree(cur_softc, &falcon_lock);
793 	}
794 
795 	if (!falcon_lock && (issue_q != NULL)) {
796 		/*
797 		 * We must (re)claim DMA access as there are jobs
798 		 * waiting in the issue queue.
799 		 */
800 		st_dmagrab((dma_farg)ncr_ctrl_intr, (dma_farg)run_main,
801 						cur_softc, &falcon_lock, 0);
802 	}
803 }
804 
805 static void
806 fal1_dma(dir, nsects, reqp)
807 u_int	dir, nsects;
808 SC_REQ	*reqp;
809 {
810 	dir <<= 8;
811 	st_dmaaddr_set((caddr_t)reqp->dm_cur->dm_addr);
812 	DMA->dma_mode = 0x90 | dir;
813 	DMA->dma_mode = 0x90 | (dir ^ DMA_WRBIT);
814 	DMA->dma_mode = 0x90 | dir;
815 	DMA->dma_data = nsects;
816 	delay(2);	/* _really_ needed (Thomas Gerner) */
817 	DMA->dma_mode = 0x10 | dir;
818 }
819 
820 static void
821 scsi_falcon_dmasetup(reqp, phase, mode)
822 SC_REQ	*reqp;
823 u_int	phase;
824 u_char	mode;
825 {
826 	int	nsects = reqp->dm_cur->dm_count / 512; /* XXX */
827 
828 	/*
829 	 * XXX: We should probably clear the fifo before putting the
830 	 *      5380 into DMA-mode.
831 	 */
832 	if (PH_IN(phase)) {
833 		set_falcon_5380_reg(NCR5380_ICOM, 0);
834 		set_falcon_5380_reg(NCR5380_MODE, mode);
835 		set_falcon_5380_reg(NCR5380_IRCV, 0);
836 		fal1_dma(0, nsects, reqp);
837 	}
838 	else {
839 		set_falcon_5380_reg(NCR5380_MODE, mode);
840 		set_falcon_5380_reg(NCR5380_ICOM, SC_ADTB);
841 		set_falcon_5380_reg(NCR5380_DMSTAT, 0);
842 		fal1_dma(1, nsects, reqp);
843 	}
844 }
845 
846 static int
847 falcon_poll_edma(reqp)
848 SC_REQ	*reqp;
849 {
850 	int	timeout = 9000; /* XXX */
851 
852 	/*
853 	 * Because of the Falcon hardware, it is impossible to reach
854 	 * the 5380 while doing DMA-transfers. So we have to rely on
855 	 * the interrupt line to determine if DMA-has finished. the
856 	 * DMA-controller itself will never fire an interrupt. This means
857 	 * that 'broken-up' DMA transfers are not (yet) possible on the
858 	 * Falcon.
859 	 */
860 	for (;;) {
861 		delay(20);
862 		if (--timeout <= 0) {
863 			ncr_tprint(reqp, "Timeout on polled transfer\n");
864 			reqp->xs->error = XS_TIMEOUT;
865 			return(0);
866 		}
867 		if (!(MFP->mf_gpip & IO_DINT))
868 			break;
869 	}
870 	return(1);
871 }
872 
873 static int
874 falcon_get_dma_result(reqp, bytes_left)
875 SC_REQ	*reqp;
876 u_long	*bytes_left;
877 {
878 	int	rv = 0;
879 	int	st_dmastat;
880 	u_long	bytes_done;
881 
882 	/*
883 	 * Select sector counter register first (See Atari docu.)
884 	 */
885 	DMA->dma_mode = 0x90;
886 	if (!(st_dmastat = DMA->dma_stat) & 0x01) {
887 		/*
888 		 * Misc. DMA-error according to Atari...
889 		 */
890 		ncr_tprint(reqp, "Unknow ST-SCSI error near 0x%x\n",
891 							st_dmaaddr_get());
892 		reqp->xs->error = XS_DRIVER_STUFFUP;
893 		rv = 1;
894 	}
895 	/*
896 	 * Because we NEVER start DMA on the Falcon when the data size
897 	 * is not a multiple of 512 bytes, we can safely round down the
898 	 * byte count on writes. We need to because in case of a disconnect,
899 	 * the DMA has already prefetched the next couple of bytes.
900 	 * On read, these byte counts are an error. They are logged and
901 	 * should be handled by the mi-part of the driver.
902 	 * NOTE: We formerly did this by using the 'byte-count-zero' bit
903 	 *       of the DMA controller, but this didn't seem to work???
904          *       [lwp 29/06/96]
905 	 */
906 	bytes_done = st_dmaaddr_get() - reqp->dm_cur->dm_addr;
907 	if (bytes_done & 511) {
908 		if (PH_IN(reqp->phase)) {
909 			ncr_tprint(reqp, "Byte count on read not a multiple "
910 					 "of 512 (%ld)\n", bytes_done);
911 		}
912 		bytes_done &= ~511;
913 	}
914 	if ((*bytes_left = reqp->dm_cur->dm_count - bytes_done) == 0)
915 		rv = 1;
916 	return(rv);
917 }
918 
919 static int
920 falcon_can_access_5380()
921 {
922 	if (connected && (connected->dr_flag & DRIVER_IN_DMA)
923 		&& (MFP->mf_gpip & IO_DINT))
924 			return(0);
925 	return(1);
926 }
927 
928 #endif /* defined(FALCON_SCSI) */
929 
930 #if defined(TT_SCSI) && defined(FALCON_SCSI)
931 /*
932  * Define some functions to support _both_ TT and Falcon SCSI
933  */
934 
935 /*
936  * The prototypes first...
937  */
938 static void	scsi_mach_init __P((struct ncr_softc *));
939        void	scsi_ienable __P((void));
940        void	scsi_idisable __P((void));
941        void	scsi_clr_ipend __P((void));
942        int	scsi_ipending __P((void));
943        void	scsi_dma_setup __P((SC_REQ *, u_int, u_char));
944        int	wrong_dma_range __P((SC_REQ *, struct dma_chain *));
945        int	poll_edma __P((SC_REQ *));
946        int	get_dma_result __P((SC_REQ *, u_long *));
947        int	can_access_5380 __P((void));
948 
949 /*
950  * Register access will be done through the following 2 function pointers.
951  */
952 static u_char	(*get_5380_reg) __P((u_short));
953 static void	(*set_5380_reg) __P((u_short, u_short));
954 
955 #define	GET_5380_REG	(*get_5380_reg)
956 #define	SET_5380_REG	(*set_5380_reg)
957 
958 static void
959 scsi_mach_init(sc)
960 struct ncr_softc	*sc;
961 {
962 	if (machineid & ATARI_FALCON) {
963 		get_5380_reg = get_falcon_5380_reg;
964 		set_5380_reg = set_falcon_5380_reg;
965 		scsi_falcon_init(sc);
966 	}
967 	else {
968 		get_5380_reg = get_tt_5380_reg;
969 		set_5380_reg = set_tt_5380_reg;
970 		scsi_tt_init(sc);
971 	}
972 }
973 
974 extern __inline__ void
975 scsi_ienable()
976 {
977 	if (machineid & ATARI_FALCON)
978 		scsi_falcon_ienable();
979 	else scsi_tt_ienable();
980 }
981 
982 extern __inline__ void
983 scsi_idisable()
984 {
985 	if (machineid & ATARI_FALCON)
986 		scsi_falcon_idisable();
987 	else scsi_tt_idisable();
988 }
989 
990 extern __inline__ void
991 scsi_clr_ipend()
992 {
993 	if (machineid & ATARI_FALCON)
994 		scsi_falcon_clr_ipend();
995 	else scsi_tt_clr_ipend();
996 }
997 
998 extern __inline__ int
999 scsi_ipending()
1000 {
1001 	if (machineid & ATARI_FALCON)
1002 		return(scsi_falcon_ipending());
1003 	else return (GET_TT_REG(NCR5380_DMSTAT) & SC_IRQ_SET);
1004 }
1005 
1006 extern __inline__ void
1007 scsi_dma_setup(reqp, phase, mbase)
1008 SC_REQ	*reqp;
1009 u_int	phase;
1010 u_char	mbase;
1011 {
1012 	if (machineid & ATARI_FALCON)
1013 		scsi_falcon_dmasetup(reqp, phase, mbase);
1014 	else scsi_tt_dmasetup(reqp, phase, mbase);
1015 }
1016 
1017 extern __inline__ int
1018 wrong_dma_range(reqp, dm)
1019 SC_REQ			*reqp;
1020 struct dma_chain	*dm;
1021 {
1022 	if (machineid & ATARI_FALCON)
1023 		return(falcon_wrong_dma_range(reqp, dm));
1024 	else return(tt_wrong_dma_range(reqp, dm));
1025 }
1026 
1027 extern __inline__ int
1028 poll_edma(reqp)
1029 SC_REQ	*reqp;
1030 {
1031 	if (machineid & ATARI_FALCON)
1032 		return(falcon_poll_edma(reqp));
1033 	else return(tt_poll_edma(reqp));
1034 }
1035 
1036 extern __inline__ int
1037 get_dma_result(reqp, bytes_left)
1038 SC_REQ	*reqp;
1039 u_long	*bytes_left;
1040 {
1041 	if (machineid & ATARI_FALCON)
1042 		return(falcon_get_dma_result(reqp, bytes_left));
1043 	else return(tt_get_dma_result(reqp, bytes_left));
1044 }
1045 
1046 extern __inline__ int
1047 can_access_5380()
1048 {
1049 	if (machineid & ATARI_FALCON)
1050 		return(falcon_can_access_5380());
1051 	return(1);
1052 }
1053 
1054 #define emulated_dma()		((machineid & ATARI_HADES) ? 1 : 0)
1055 
1056 /*
1057  * Locking stuff. All turns into NOP's on the TT.
1058  */
1059 #define	fair_to_keep_dma()	((machineid & ATARI_FALCON) ?		\
1060 						!st_dmawanted() : 1)
1061 #define	claimed_dma()		((machineid & ATARI_FALCON) ?		\
1062 						falcon_claimed_dma() : 1)
1063 #define reconsider_dma()	{					\
1064 					if(machineid & ATARI_FALCON)	\
1065 						falcon_reconsider_dma();\
1066 				}
1067 #endif /* defined(TT_SCSI) && defined(FALCON_SCSI) */
1068 
1069 /**********************************************
1070  * Functions present for both TT and Falcon.  *
1071  **********************************************/
1072 /*
1073  * Our autoconfig matching function
1074  */
1075 static int
1076 machine_match(struct device *pdp, void *match, void *auxp,
1077 						struct cfdriver *cd)
1078 {
1079 	struct cfdata *cdp = match;
1080 
1081 	if (strcmp(auxp, cd->cd_name))
1082 		return(0);
1083 	if (cdp->cf_unit != 0)	/* Only one unit	*/
1084 		return(0);
1085 	return(1);
1086 }
1087 
1088 /*
1089  * Bounce buffer (de)allocation. Those buffers are gotten from the ST-mem
1090  * pool. Allocation here is both contiguous and in the lower 16Mb of
1091  * the address space. Thus being DMA-able for all controllers.
1092  */
1093 static u_char *
1094 alloc_bounceb(u_long len)
1095 {
1096 	void	*tmp;
1097 
1098 	return((u_char *)alloc_stmem(len, &tmp));
1099 }
1100 
1101 static void
1102 free_bounceb(u_char *bounceb)
1103 {
1104 	free_stmem(bounceb);
1105 }
1106 
1107 /*
1108  * 5380 interrupt.
1109  */
1110 void
1111 scsi_ctrl(int sr)
1112 {
1113 	if (GET_5380_REG(NCR5380_DMSTAT) & SC_IRQ_SET) {
1114 		scsi_idisable();
1115 		if (!BASEPRI(sr))
1116 			add_sicallback((si_farg)ncr_ctrl_intr,
1117 						(void *)cur_softc, 0);
1118 		else {
1119 			spl1();
1120 			ncr_ctrl_intr(cur_softc);
1121 			spl0();
1122 		}
1123 	}
1124 }
1125 
1126 /*
1127  * DMA controller interrupt
1128  */
1129 void
1130 scsi_dma(int sr)
1131 {
1132 	SC_REQ	*reqp;
1133 
1134 	if ((reqp = connected) && (reqp->dr_flag & DRIVER_IN_DMA)) {
1135 		scsi_idisable();
1136 		if (!BASEPRI(sr))
1137 			add_sicallback((si_farg)ncr_dma_intr,
1138 					(void *)cur_softc, 0);
1139 		else {
1140 			spl1();
1141 			ncr_dma_intr(cur_softc);
1142 			spl0();
1143 		}
1144 	}
1145 }
1146 
1147 /*
1148  * Last but not least... Include the general driver code
1149  */
1150 #include <atari/dev/ncr5380.c>
1151