xref: /netbsd-src/sys/arch/atari/dev/atari5380.c (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1 /*	$NetBSD: atari5380.c,v 1.35 2003/05/03 18:10:45 wiz 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 "opt_atariscsi.h"
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/device.h>
39 #include <sys/buf.h>
40 #include <dev/scsipi/scsi_all.h>
41 #include <dev/scsipi/scsipi_all.h>
42 #include <dev/scsipi/scsi_message.h>
43 #include <dev/scsipi/scsiconf.h>
44 
45 #include <uvm/uvm_extern.h>
46 
47 #include <m68k/asm_single.h>
48 #include <m68k/cpu.h>
49 #include <m68k/cacheops.h>
50 
51 #include <atari/atari/stalloc.h>
52 
53 /*
54  * Include the driver definitions
55  */
56 #include <atari/dev/ncr5380reg.h>
57 
58 #include <machine/stdarg.h>
59 #include <machine/iomap.h>
60 #include <machine/mfp.h>
61 
62 #include <atari/atari/intr.h>
63 
64 #if defined(FALCON_SCSI)
65 #include <machine/dma.h>
66 #endif
67 
68 /*
69  * Set the various driver options
70  */
71 #define	NREQ		18	/* Size of issue queue			*/
72 #define	AUTO_SENSE	1	/* Automatically issue a request-sense 	*/
73 
74 #define	DRNAME		ncrscsi	/* used in various prints		*/
75 #undef	DBG_SEL			/* Show the selection process		*/
76 #undef	DBG_REQ			/* Show enqueued/ready requests		*/
77 #undef	DBG_ERR_RET		/* Show requests with != 0 return code	*/
78 #undef	DBG_NOWRITE		/* Do not allow writes to the targets	*/
79 #undef	DBG_PIO			/* Show the polled-I/O process		*/
80 #undef	DBG_INF			/* Show information transfer process	*/
81 #define	DBG_NOSTATIC		/* No static functions, all in DDB trace*/
82 #define	DBG_PID		15	/* Keep track of driver			*/
83 #define	REAL_DMA		/* Use DMA if sensible			*/
84 #if defined(FALCON_SCSI)
85 #define	REAL_DMA_POLL	1	/* 1: Poll for end of DMA-transfer	*/
86 #else
87 #define	REAL_DMA_POLL	0	/* 1: Poll for end of DMA-transfer	*/
88 #endif
89 #undef	USE_PDMA		/* Use special pdma-transfer function	*/
90 #define MIN_PHYS	65536	/*BARF!!!!*/
91 
92 /*
93  * Include more driver definitions
94  */
95 #include <atari/dev/ncr5380var.h>
96 
97 /*
98  * The atari specific driver options
99  */
100 #undef	NO_TTRAM_DMA		/* Do not use DMA to TT-ram. This	*/
101 				/*    fails on older atari's		*/
102 #define	ENABLE_NCR5380(sc)	cur_softc = sc;
103 
104 static u_char	*alloc_bounceb __P((u_long));
105 static void	free_bounceb __P((u_char *));
106 static int	machine_match __P((struct device *, void *, void *,
107 							struct cfdriver *));
108        void	scsi_ctrl __P((int));
109        void	scsi_dma __P((int));
110 
111 /*
112  * Functions that do nothing on the atari
113  */
114 #define	pdma_ready()		0
115 
116 #if defined(TT_SCSI)
117 
118 void	ncr5380_drq_intr __P((int));
119 
120 /*
121  * Define all the things we need of the DMA-controller
122  */
123 #define	SCSI_DMA	((struct scsi_dma *)AD_SCSI_DMA)
124 #define	SCSI_5380	((struct scsi_5380 *)AD_NCR5380)
125 
126 struct scsi_dma {
127 	volatile u_char		s_dma_ptr[8];	/* use only the odd bytes */
128 	volatile u_char		s_dma_cnt[8];	/* use only the odd bytes */
129 	volatile u_char		s_dma_res[4];	/* data residue register  */
130 	volatile u_char		s_dma_gap;	/* not used		  */
131 	volatile u_char		s_dma_ctrl;	/* control register	  */
132 	volatile u_char		s_dma_gap2;	/* not used		  */
133 	volatile u_char		s_hdma_ctrl;	/* Hades control register */
134 };
135 
136 #define	set_scsi_dma(addr, val)	(void)(					\
137 	{								\
138 	u_char	*address = (u_char*)addr+1;				\
139 	u_long	nval	 = (u_long)val;					\
140 	__asm("movepl	%0, %1@(0)": :"d" (nval), "a" (address));	\
141 	})
142 
143 #define	get_scsi_dma(addr, res)	(					\
144 	{								\
145 	u_char	*address = (u_char*)addr+1;				\
146 	u_long	nval;							\
147 	__asm("movepl	%1@(0), %0": "=d" (nval) : "a" (address));	\
148 	res = (u_long)nval;						\
149 	})
150 
151 /*
152  * Defines for TT-DMA control register
153  */
154 #define	SD_BUSERR	0x80		/* 1 = transfer caused bus error*/
155 #define	SD_ZERO		0x40		/* 1 = byte counter is zero	*/
156 #define	SD_ENABLE	0x02		/* 1 = Enable DMA		*/
157 #define	SD_OUT		0x01		/* Direction: memory to SCSI	*/
158 #define	SD_IN		0x00		/* Direction: SCSI to memory	*/
159 
160 /*
161  * Defines for Hades-DMA control register
162  */
163 #define	SDH_BUSERR	0x02		/* 1 = Bus error		*/
164 #define SDH_EOP		0x01		/* 1 = Signal EOP on 5380	*/
165 #define	SDH_ZERO	0x40		/* 1 = Byte counter is zero	*/
166 
167 /*
168  * Define the 5380 register set
169  */
170 struct scsi_5380 {
171 	volatile u_char	scsi_5380[16];	/* use only the odd bytes	*/
172 };
173 #endif /* TT_SCSI */
174 
175 /**********************************************
176  * Variables present for both TT and Falcon.  *
177  **********************************************/
178 
179 /*
180  * Softc of currently active controller (a bit of fake; we only have one)
181  */
182 static struct ncr_softc	*cur_softc;
183 
184 #if defined(TT_SCSI) && !defined(FALCON_SCSI)
185 /*
186  * We can be more efficient for some functions when only TT_SCSI is selected
187  */
188 #define	GET_5380_REG(rnum)	SCSI_5380->scsi_5380[(rnum << 1) | 1]
189 #define	SET_5380_REG(rnum,val)	(SCSI_5380->scsi_5380[(rnum << 1) | 1] = val)
190 
191 #define scsi_mach_init(sc)	scsi_tt_init(sc)
192 #define scsi_ienable()		scsi_tt_ienable()
193 #define scsi_idisable()		scsi_tt_idisable()
194 #define	scsi_clr_ipend()	scsi_tt_clr_ipend()
195 #define scsi_ipending()		(GET_5380_REG(NCR5380_DMSTAT) & SC_IRQ_SET)
196 #define scsi_dma_setup(r,p,m)	scsi_tt_dmasetup(r, p, m)
197 #define wrong_dma_range(r,d)	tt_wrong_dma_range(r, d)
198 #define poll_edma(reqp)		tt_poll_edma(reqp)
199 #define get_dma_result(r, b)	tt_get_dma_result(r, b)
200 #define	can_access_5380()	1
201 #define emulated_dma()		((machineid & ATARI_HADES) ? 1 : 0)
202 
203 #define fair_to_keep_dma()	1
204 #define claimed_dma()		1
205 #define reconsider_dma()
206 
207 #endif /* defined(TT_SCSI) && !defined(FALCON_SCSI) */
208 
209 #if defined(TT_SCSI)
210 
211 /*
212  * Prototype functions defined below
213  */
214 #ifdef NO_TTRAM_DMA
215 static int tt_wrong_dma_range __P((SC_REQ *, struct dma_chain *));
216 #endif
217 static void	scsi_tt_init __P((struct ncr_softc *));
218 static u_char	get_tt_5380_reg __P((u_short));
219 static void	set_tt_5380_reg __P((u_short, u_short));
220 static void	scsi_tt_dmasetup __P((SC_REQ *, u_int, u_char));
221 static int	tt_poll_edma __P((SC_REQ *));
222 static u_char	*ptov __P((SC_REQ *, u_long*));
223 static int	tt_get_dma_result __P((SC_REQ *, u_long *));
224        void	scsi_tt_ienable __P((void));
225        void	scsi_tt_idisable __P((void));
226        void	scsi_tt_clr_ipend __P((void));
227 
228 /*
229  * Define these too, so we can use them locally...
230  */
231 #define	GET_TT_REG(rnum)	SCSI_5380->scsi_5380[(rnum << 1) | 1]
232 #define	SET_TT_REG(rnum,val)	(SCSI_5380->scsi_5380[(rnum << 1) | 1] = val)
233 
234 #ifdef NO_TTRAM_DMA
235 static int
236 tt_wrong_dma_range(reqp, dm)
237 SC_REQ			*reqp;
238 struct dma_chain	*dm;
239 {
240 	if (dm->dm_addr & 0xff000000) {
241 		reqp->dr_flag |= DRIVER_BOUNCING;
242 		return(1);
243 	}
244 	return(0);
245 }
246 #else
247 #define	tt_wrong_dma_range(reqp, dm)	0
248 #endif
249 
250 static void
251 scsi_tt_init(struct ncr_softc *sc)
252 {
253 	/*
254 	 * Enable SCSI-related interrupts
255 	 */
256 	MFP2->mf_aer  |= 0x80;		/* SCSI IRQ goes HIGH!!!!!	*/
257 
258 	if (machineid & ATARI_TT) {
259 		/* SCSI-DMA interrupts		*/
260 		MFP2->mf_ierb |= IB_SCDM;
261 		MFP2->mf_iprb  = (u_int8_t)~IB_SCDM;
262 		MFP2->mf_imrb |= IB_SCDM;
263 	}
264 	else if (machineid & ATARI_HADES) {
265 		SCSI_DMA->s_hdma_ctrl = 0;
266 
267 		if (intr_establish(2, AUTO_VEC, 0,
268 					(hw_ifun_t)ncr5380_drq_intr,
269 					NULL) == NULL)
270 		panic("scsi_tt_init: Can't establish drq-interrupt");
271 	}
272 	else panic("scsi_tt_init: should not come here");
273 
274 	MFP2->mf_iera |= IA_SCSI;	/* SCSI-5380 interrupts		*/
275 	MFP2->mf_ipra  = (u_int8_t)~IA_SCSI;
276 	MFP2->mf_imra |= IA_SCSI;
277 
278 	/*
279 	 * LWP: DMA transfers to TT-ram causes data to be garbeled
280 	 * without notice on some revisons of the TT-mainboard.
281 	 * When program's generate misterious Segmentations faults,
282 	 * try turning on NO_TTRAM_DMA.
283 	 */
284 #ifdef NO_TTRAM_DMA
285 	printf(": DMA to TT-RAM is disabled!");
286 #endif
287 }
288 
289 static u_char
290 get_tt_5380_reg(u_short rnum)
291 {
292 	return(SCSI_5380->scsi_5380[(rnum << 1) | 1]);
293 }
294 
295 static void
296 set_tt_5380_reg(u_short rnum, u_short val)
297 {
298 	SCSI_5380->scsi_5380[(rnum << 1) | 1] = val;
299 }
300 
301 extern __inline__ void
302 scsi_tt_ienable(void)
303 {
304 	if (machineid & ATARI_TT)
305 		single_inst_bset_b(MFP2->mf_imrb, IB_SCDM);
306 	single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
307 }
308 
309 extern __inline__ void
310 scsi_tt_idisable(void)
311 {
312 	if (machineid & ATARI_TT)
313 		single_inst_bclr_b(MFP2->mf_imrb, IB_SCDM);
314 	single_inst_bclr_b(MFP2->mf_imra, IA_SCSI);
315 }
316 
317 extern __inline__ void
318 scsi_tt_clr_ipend(void)
319 {
320 	int	tmp;
321 
322 	SCSI_DMA->s_dma_ctrl = 0;
323 	tmp = GET_TT_REG(NCR5380_IRCV);
324 	if (machineid & ATARI_TT)
325 		MFP2->mf_iprb = (u_int8_t)~IB_SCDM;
326 	MFP2->mf_ipra = (u_int8_t)~IA_SCSI;
327 
328 	/*
329 	 * Remove interrupts already scheduled.
330 	 */
331 	rem_sicallback((si_farg)ncr_ctrl_intr);
332 	rem_sicallback((si_farg)ncr_dma_intr);
333 }
334 
335 static void
336 scsi_tt_dmasetup(SC_REQ *reqp, u_int phase, u_char	mode)
337 {
338 	if (PH_IN(phase)) {
339 		SCSI_DMA->s_dma_ctrl = SD_IN;
340 		if (machineid & ATARI_HADES)
341 		    SCSI_DMA->s_hdma_ctrl &= ~(SDH_BUSERR|SDH_EOP);
342 		set_scsi_dma(&(SCSI_DMA->s_dma_ptr), reqp->dm_cur->dm_addr);
343 		set_scsi_dma(&(SCSI_DMA->s_dma_cnt), reqp->dm_cur->dm_count);
344 		SET_TT_REG(NCR5380_ICOM, 0);
345 		SET_TT_REG(NCR5380_MODE, mode);
346 		SCSI_DMA->s_dma_ctrl = SD_ENABLE;
347 		SET_TT_REG(NCR5380_IRCV, 0);
348 	}
349 	else {
350 		SCSI_DMA->s_dma_ctrl = SD_OUT;
351 		if (machineid & ATARI_HADES)
352 		    SCSI_DMA->s_hdma_ctrl &= ~(SDH_BUSERR|SDH_EOP);
353 		set_scsi_dma(&(SCSI_DMA->s_dma_ptr), reqp->dm_cur->dm_addr);
354 		set_scsi_dma(&(SCSI_DMA->s_dma_cnt), reqp->dm_cur->dm_count);
355 		SET_TT_REG(NCR5380_MODE, mode);
356 		SET_TT_REG(NCR5380_ICOM, SC_ADTB);
357 		SET_TT_REG(NCR5380_DMSTAT, 0);
358 		SCSI_DMA->s_dma_ctrl = SD_ENABLE|SD_OUT;
359 	}
360 }
361 
362 static int
363 tt_poll_edma(SC_REQ *reqp)
364 {
365 	u_char	dmstat, dmastat;
366 	int	timeout = 9000; /* XXX */
367 
368 	/*
369 	 * We wait here until the DMA has finished. This can be
370 	 * achieved by checking the following conditions:
371 	 *   - 5380:
372 	 *	- End of DMA flag is set
373 	 *	- We lost BSY (error!!)
374 	 *	- A phase mismatch has occurred (partial transfer)
375 	 *   - DMA-controller:
376 	 *	- A bus error occurred (Kernel error!!)
377 	 *	- All bytes are transferred
378 	 * If one of the terminating conditions was met, we call
379 	 * 'dma_ready' to check errors and perform the bookkeeping.
380 	 */
381 
382 	scsi_tt_idisable();
383 	for (;;) {
384 		delay(20);
385 		if (--timeout <= 0) {
386 			ncr_tprint(reqp, "timeout on polled transfer\n");
387 			reqp->xs->error = XS_TIMEOUT;
388 			scsi_tt_ienable();
389 			return(0);
390 		}
391 		dmstat  = GET_TT_REG(NCR5380_DMSTAT);
392 
393 		if ((machineid & ATARI_HADES) && (dmstat & SC_DMA_REQ)) {
394 			ncr5380_drq_intr(1);
395 			dmstat  = GET_TT_REG(NCR5380_DMSTAT);
396 		}
397 
398 		dmastat = SCSI_DMA->s_dma_ctrl;
399 		if (dmstat & (SC_END_DMA|SC_BSY_ERR|SC_IRQ_SET))
400 			break;
401 		if (!(dmstat & SC_PHS_MTCH))
402 			break;
403 		if (dmastat & (SD_BUSERR|SD_ZERO))
404 			break;
405 	}
406 	scsi_tt_ienable();
407 	return(1);
408 }
409 
410 /*
411  * Convert physical DMA address to a virtual address.
412  */
413 static u_char *
414 ptov(SC_REQ *reqp, u_long *phaddr)
415 {
416 	struct dma_chain	*dm;
417 	u_char			*vaddr;
418 
419 	dm = reqp->dm_chain;
420 	vaddr = reqp->xdata_ptr;
421 	for(; dm < reqp->dm_cur; dm++)
422 		vaddr += dm->dm_count;
423 	vaddr += (u_long)phaddr - dm->dm_addr;
424 	return(vaddr);
425 }
426 
427 static int
428 tt_get_dma_result(SC_REQ *reqp, u_long *bytes_left)
429 {
430 	int	dmastat, dmstat;
431 	u_char	*byte_p;
432 	u_long	leftover;
433 
434 	dmastat = SCSI_DMA->s_dma_ctrl;
435 	dmstat  = GET_TT_REG(NCR5380_DMSTAT);
436 	get_scsi_dma(SCSI_DMA->s_dma_cnt, leftover);
437 	get_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)byte_p);
438 
439 	if (dmastat & SD_BUSERR) {
440 		/*
441 		 * The DMA-controller seems to access 8 bytes beyond
442 		 * it's limits on output. Therefore check also the byte
443 		 * count. If it's zero, ignore the bus error.
444 		 */
445 		if (leftover != 0) {
446 			ncr_tprint(reqp,
447 				"SCSI-DMA buserror - accessing 0x%x\n", byte_p);
448 			reqp->xs->error = XS_DRIVER_STUFFUP;
449 		}
450 	}
451 
452 	/*
453 	 * We handle the following special condition below:
454 	 *  -- The device disconnects in the middle of a write operation --
455 	 * In this case, the 5380 has already pre-fetched the next byte from
456 	 * the DMA-controller before the phase mismatch occurs. Therefore,
457 	 * leftover is 1 too low.
458 	 * This does not always happen! Therefore, we only do this when
459 	 * leftover is odd. This assumes that DMA transfers are _even_! This
460 	 * is normally the case on disks and types but might not always be.
461 	 * XXX: Check if ACK is consistently high on these occasions LWP
462 	 */
463 	if ((leftover & 1) && !(dmstat & SC_PHS_MTCH) && PH_OUT(reqp->phase))
464 		leftover++;
465 
466 	/*
467 	 * Check if there are some 'restbytes' left in the DMA-controller.
468 	 */
469 	if ((machineid & ATARI_TT) && ((u_long)byte_p & 3)
470 	    && PH_IN(reqp->phase)) {
471 		u_char	*p, *q;
472 
473 		p = ptov(reqp, (u_long *)((u_long)byte_p & ~3));
474 		q = (u_char*)&(SCSI_DMA->s_dma_res);
475 		switch ((u_long)byte_p & 3) {
476 			case 3: *p++ = *q++;
477 			case 2: *p++ = *q++;
478 			case 1: *p++ = *q++;
479 		}
480 	}
481 	*bytes_left = leftover;
482 	return ((dmastat & (SD_BUSERR|SD_ZERO)) ? 1 : 0);
483 }
484 
485 static u_char *dma_ptr;
486 void
487 ncr5380_drq_intr(poll)
488 int poll;
489 {
490 extern	int			*nofault;
491 	label_t			faultbuf;
492 	int			write;
493 	u_long	 		count;
494 	u_char			*data_p = (u_char*)(stio_addr+0x741);
495 
496 	/*
497 	 * Block SCSI interrupts while emulating DMA. They come
498 	 * at a higher priority.
499 	 */
500 	single_inst_bclr_b(MFP2->mf_imra, IA_SCSI);
501 
502 	/*
503 	 * Setup for a possible bus error caused by SCSI controller
504 	 * switching out of DATA-IN/OUT before we're done with the
505 	 * current transfer.
506 	 */
507 	nofault = (int *) &faultbuf;
508 
509 	if (setjmp((label_t *) nofault)) {
510 		u_char	*ptr;
511 		u_long	cnt, tmp;
512 
513 		PID("drq berr");
514 		nofault = (int *) 0;
515 
516 		/*
517 		 * Determine number of bytes transferred
518 		 */
519 		get_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)ptr);
520 		cnt = dma_ptr - ptr;
521 
522 		if (cnt != 0) {
523 			/*
524 			 * Update the DMA pointer/count fields
525 			 */
526 			set_scsi_dma(SCSI_DMA->s_dma_ptr, dma_ptr);
527 			get_scsi_dma(SCSI_DMA->s_dma_cnt, tmp);
528 			set_scsi_dma(SCSI_DMA->s_dma_cnt, tmp - cnt);
529 
530 			if (tmp > cnt) {
531 				/*
532 				 * Still more to transfer
533 				 */
534 				if (!poll)
535 				   single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
536 				return;
537 			}
538 
539 			/*
540 			 * Signal EOP to 5380
541 			 */
542 			SCSI_DMA->s_hdma_ctrl |= SDH_EOP;
543 		}
544 		else {
545 			nofault = (int *) &faultbuf;
546 
547 			/*
548 			 * Try to figure out if the byte-count was
549 			 * zero because there was no (more) data or
550 			 * because the dma_ptr is bogus.
551 			 */
552 			if (setjmp((label_t *) nofault)) {
553 				/*
554 				 * Set the bus-error bit
555 				 */
556 				SCSI_DMA->s_hdma_ctrl |= SDH_BUSERR;
557 			}
558 			__asm __volatile ("tstb	%0@(0)": : "a" (dma_ptr));
559 			nofault = (int *)0;
560 		}
561 
562 		/*
563 		 * Schedule an interrupt
564 		 */
565 		if (!poll && (SCSI_DMA->s_dma_ctrl & SD_ENABLE))
566 		    add_sicallback((si_farg)ncr_dma_intr, (void *)cur_softc, 0);
567 
568 		/*
569 		 * Clear DMA-mode
570 		 */
571 		SCSI_DMA->s_dma_ctrl &= ~SD_ENABLE;
572 		if (!poll)
573 			single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
574 
575 		return;
576 	}
577 
578 	write = (SCSI_DMA->s_dma_ctrl & SD_OUT) ? 1 : 0;
579 #if DBG_PID
580 	if (write) {
581 		PID("drq (in)");
582 	} else {
583 		PID("drq (out)");
584 	}
585 #endif
586 
587 	get_scsi_dma(SCSI_DMA->s_dma_cnt, count);
588 	get_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)dma_ptr);
589 
590 	/*
591 	 * Keep pushing bytes until we're done or a bus-error
592 	 * signals that the SCSI controller is not ready.
593 	 * NOTE: I tried some optimalizations in these loops,
594 	 *       but they had no effect on transfer speed.
595 	 */
596 	if (write) {
597 		while(count--) {
598 			*data_p = *dma_ptr++;
599 		}
600 	}
601 	else {
602 		while(count--) {
603 			*dma_ptr++ = *data_p;
604 		}
605 	}
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 	 * Schedule an interrupt
615 	 */
616 	if (!poll && (SCSI_DMA->s_dma_ctrl & SD_ENABLE))
617 	    add_sicallback((si_farg)ncr_dma_intr, (void *)cur_softc, 0);
618 
619 	/*
620 	 * Clear DMA-mode
621 	 */
622 	SCSI_DMA->s_dma_ctrl &= ~SD_ENABLE;
623 
624 	/*
625 	 * Update the DMA 'registers' to reflect that all bytes
626 	 * have been transfered and tell this to the 5380 too.
627 	 */
628 	set_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)dma_ptr);
629 	set_scsi_dma(SCSI_DMA->s_dma_cnt, 0);
630 	SCSI_DMA->s_hdma_ctrl |= SDH_EOP;
631 
632 	PID("end drq");
633 	if (!poll)
634 		single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
635 
636 	return;
637 }
638 
639 #endif /* defined(TT_SCSI) */
640 
641 #if defined(FALCON_SCSI) && !defined(TT_SCSI)
642 
643 #define	GET_5380_REG(rnum)	get_falcon_5380_reg(rnum)
644 #define	SET_5380_REG(rnum,val)	set_falcon_5380_reg(rnum, val)
645 #define scsi_mach_init(sc)	scsi_falcon_init(sc)
646 #define scsi_ienable()		scsi_falcon_ienable()
647 #define scsi_idisable()		scsi_falcon_idisable()
648 #define	scsi_clr_ipend()	scsi_falcon_clr_ipend()
649 #define	scsi_ipending()		scsi_falcon_ipending()
650 #define scsi_dma_setup(r,p,m)	scsi_falcon_dmasetup(r, p, m)
651 #define wrong_dma_range(r,d)	falcon_wrong_dma_range(r, d)
652 #define poll_edma(reqp)		falcon_poll_edma(reqp)
653 #define get_dma_result(r, b)	falcon_get_dma_result(r, b)
654 #define	can_access_5380()	falcon_can_access_5380()
655 #define	emulated_dma()		0
656 
657 #define fair_to_keep_dma()	(!st_dmawanted())
658 #define claimed_dma()		falcon_claimed_dma()
659 #define reconsider_dma()	falcon_reconsider_dma()
660 
661 #endif /* defined(FALCON_SCSI) && !defined(TT_SCSI) */
662 
663 #if defined(FALCON_SCSI)
664 
665 /*
666  * Prototype functions defined below
667  */
668 static void	scsi_falcon_init __P((struct ncr_softc *));
669 static u_char	get_falcon_5380_reg __P((u_short));
670 static void	set_falcon_5380_reg __P((u_short, u_short));
671 static int	falcon_wrong_dma_range __P((SC_REQ *, struct dma_chain *));
672 static void	fal1_dma __P((u_int, u_int, SC_REQ *));
673 static void	scsi_falcon_dmasetup __P((SC_REQ  *, u_int, u_char));
674 static int	falcon_poll_edma __P((SC_REQ  *));
675 static int	falcon_get_dma_result __P((SC_REQ  *, u_long *));
676        int	falcon_can_access_5380 __P((void));
677        void	scsi_falcon_clr_ipend __P((void));
678        void	scsi_falcon_idisable __P((void));
679        void	scsi_falcon_ienable __P((void));
680        int	scsi_falcon_ipending __P((void));
681        int	falcon_claimed_dma __P((void));
682        void	falcon_reconsider_dma __P((void));
683 
684 static void
685 scsi_falcon_init(sc)
686 struct ncr_softc	*sc;
687 {
688 	/*
689 	 * Enable disk related interrupts
690 	 */
691 	MFP->mf_ierb  |= IB_DINT;
692 	MFP->mf_iprb   = (u_int8_t)~IB_DINT;
693 	MFP->mf_imrb  |= IB_DINT;
694 }
695 
696 static u_char
697 get_falcon_5380_reg(rnum)
698 u_short	rnum;
699 {
700 	DMA->dma_mode = DMA_SCSI + rnum;
701 	return(DMA->dma_data);
702 }
703 
704 static void
705 set_falcon_5380_reg(rnum, val)
706 u_short	rnum, val;
707 {
708 	DMA->dma_mode = DMA_SCSI + rnum;
709 	DMA->dma_data = val;
710 }
711 
712 extern __inline__ void
713 scsi_falcon_ienable()
714 {
715 	single_inst_bset_b(MFP->mf_imrb, IB_DINT);
716 }
717 
718 extern __inline__ void
719 scsi_falcon_idisable()
720 {
721 	single_inst_bclr_b(MFP->mf_imrb, IB_DINT);
722 }
723 
724 extern __inline__ void
725 scsi_falcon_clr_ipend()
726 {
727 	int	tmp;
728 
729 	tmp = get_falcon_5380_reg(NCR5380_IRCV);
730 	rem_sicallback((si_farg)ncr_ctrl_intr);
731 }
732 
733 extern __inline__ int
734 scsi_falcon_ipending()
735 {
736 	if (connected && (connected->dr_flag & DRIVER_IN_DMA)) {
737 		/*
738 		 *  XXX: When DMA is running, we are only allowed to
739 		 *       check the 5380 when DMA _might_ be finished.
740 		 */
741 		if (MFP->mf_gpip & IO_DINT)
742 		    return (0); /* XXX: Actually: we're not allowed to check */
743 
744 		/* LWP: 28-06, must be a DMA interrupt! should the
745 		 * ST-DMA unit be taken out of DMA mode?????
746 		 */
747 		DMA->dma_mode = 0x90;
748 
749 	}
750 	return(get_falcon_5380_reg(NCR5380_DMSTAT) & SC_IRQ_SET);
751 }
752 
753 static int
754 falcon_wrong_dma_range(reqp, dm)
755 SC_REQ			*reqp;
756 struct dma_chain	*dm;
757 {
758 	/*
759 	 * Do not allow chains yet! See also comment with
760 	 * falcon_poll_edma() !!!
761 	 */
762 	if (((dm - reqp->dm_chain) > 0) || (dm->dm_addr & 0xff000000)) {
763 		reqp->dr_flag |= DRIVER_BOUNCING;
764 		return(1);
765 	}
766 	/*
767 	 * Never allow DMA to happen on a Falcon when the transfer
768 	 * size is no multiple of 512. This is the transfer unit of the
769 	 * ST DMA-controller.
770 	 */
771 	if(dm->dm_count & 511)
772 		return(1);
773 	return(0);
774 }
775 
776 static	int falcon_lock = 0;
777 
778 extern __inline__ int
779 falcon_claimed_dma()
780 {
781 	if (falcon_lock != DMA_LOCK_GRANT) {
782 		if (falcon_lock == DMA_LOCK_REQ) {
783 			/*
784 			 * DMA access is being claimed.
785 			 */
786 			return(0);
787 		}
788 		if (!st_dmagrab((dma_farg)ncr_ctrl_intr, (dma_farg)run_main,
789 						cur_softc, &falcon_lock, 1))
790 			return(0);
791 	}
792 	return(1);
793 }
794 
795 extern __inline__ void
796 falcon_reconsider_dma()
797 {
798 	if (falcon_lock && (connected == NULL) && (discon_q == NULL)) {
799 		/*
800 		 * No need to keep DMA locked by us as we are not currently
801 		 * connected and no disconnected jobs are pending.
802 		 */
803 		rem_sicallback((si_farg)ncr_ctrl_intr);
804 		st_dmafree(cur_softc, &falcon_lock);
805 	}
806 
807 	if (!falcon_lock && (issue_q != NULL)) {
808 		/*
809 		 * We must (re)claim DMA access as there are jobs
810 		 * waiting in the issue queue.
811 		 */
812 		st_dmagrab((dma_farg)ncr_ctrl_intr, (dma_farg)run_main,
813 						cur_softc, &falcon_lock, 0);
814 	}
815 }
816 
817 static void
818 fal1_dma(dir, nsects, reqp)
819 u_int	dir, nsects;
820 SC_REQ	*reqp;
821 {
822 	dir <<= 8;
823 	st_dmaaddr_set((caddr_t)reqp->dm_cur->dm_addr);
824 	DMA->dma_mode = 0x90 | dir;
825 	DMA->dma_mode = 0x90 | (dir ^ DMA_WRBIT);
826 	DMA->dma_mode = 0x90 | dir;
827 	DMA->dma_data = nsects;
828 	delay(2);	/* _really_ needed (Thomas Gerner) */
829 	DMA->dma_mode = 0x10 | dir;
830 }
831 
832 static void
833 scsi_falcon_dmasetup(reqp, phase, mode)
834 SC_REQ	*reqp;
835 u_int	phase;
836 u_char	mode;
837 {
838 	int	nsects = reqp->dm_cur->dm_count / 512; /* XXX */
839 
840 	/*
841 	 * XXX: We should probably clear the fifo before putting the
842 	 *      5380 into DMA-mode.
843 	 */
844 	if (PH_IN(phase)) {
845 		set_falcon_5380_reg(NCR5380_ICOM, 0);
846 		set_falcon_5380_reg(NCR5380_MODE, mode);
847 		set_falcon_5380_reg(NCR5380_IRCV, 0);
848 		fal1_dma(0, nsects, reqp);
849 	}
850 	else {
851 		set_falcon_5380_reg(NCR5380_MODE, mode);
852 		set_falcon_5380_reg(NCR5380_ICOM, SC_ADTB);
853 		set_falcon_5380_reg(NCR5380_DMSTAT, 0);
854 		fal1_dma(1, nsects, reqp);
855 	}
856 }
857 
858 static int
859 falcon_poll_edma(reqp)
860 SC_REQ	*reqp;
861 {
862 	int	timeout = 9000; /* XXX */
863 
864 	/*
865 	 * Because of the Falcon hardware, it is impossible to reach
866 	 * the 5380 while doing DMA-transfers. So we have to rely on
867 	 * the interrupt line to determine if DMA-has finished. the
868 	 * DMA-controller itself will never fire an interrupt. This means
869 	 * that 'broken-up' DMA transfers are not (yet) possible on the
870 	 * Falcon.
871 	 */
872 	for (;;) {
873 		delay(20);
874 		if (--timeout <= 0) {
875 			ncr_tprint(reqp, "Timeout on polled transfer\n");
876 			reqp->xs->error = XS_TIMEOUT;
877 			return(0);
878 		}
879 		if (!(MFP->mf_gpip & IO_DINT))
880 			break;
881 	}
882 	return(1);
883 }
884 
885 static int
886 falcon_get_dma_result(reqp, bytes_left)
887 SC_REQ	*reqp;
888 u_long	*bytes_left;
889 {
890 	int	rv = 0;
891 	int	st_dmastat;
892 	u_long	bytes_done;
893 
894 	/*
895 	 * Select sector counter register first (See Atari docu.)
896 	 */
897 	DMA->dma_mode = 0x90;
898 	if (!(st_dmastat = DMA->dma_stat) & 0x01) {
899 		/*
900 		 * Misc. DMA-error according to Atari...
901 		 */
902 		ncr_tprint(reqp, "Unknow ST-SCSI error near 0x%x\n",
903 							st_dmaaddr_get());
904 		reqp->xs->error = XS_DRIVER_STUFFUP;
905 		rv = 1;
906 	}
907 	/*
908 	 * Because we NEVER start DMA on the Falcon when the data size
909 	 * is not a multiple of 512 bytes, we can safely round down the
910 	 * byte count on writes. We need to because in case of a disconnect,
911 	 * the DMA has already prefetched the next couple of bytes.
912 	 * On read, these byte counts are an error. They are logged and
913 	 * should be handled by the mi-part of the driver.
914 	 * NOTE: We formerly did this by using the 'byte-count-zero' bit
915 	 *       of the DMA controller, but this didn't seem to work???
916          *       [lwp 29/06/96]
917 	 */
918 	bytes_done = st_dmaaddr_get() - reqp->dm_cur->dm_addr;
919 	if (bytes_done & 511) {
920 		if (PH_IN(reqp->phase)) {
921 			ncr_tprint(reqp, "Byte count on read not a multiple "
922 					 "of 512 (%ld)\n", bytes_done);
923 		}
924 		bytes_done &= ~511;
925 	}
926 	if ((*bytes_left = reqp->dm_cur->dm_count - bytes_done) == 0)
927 		rv = 1;
928 	return(rv);
929 }
930 
931 static int
932 falcon_can_access_5380()
933 {
934 	if (connected && (connected->dr_flag & DRIVER_IN_DMA)
935 		&& (MFP->mf_gpip & IO_DINT))
936 			return(0);
937 	return(1);
938 }
939 
940 #endif /* defined(FALCON_SCSI) */
941 
942 #if defined(TT_SCSI) && defined(FALCON_SCSI)
943 /*
944  * Define some functions to support _both_ TT and Falcon SCSI
945  */
946 
947 /*
948  * The prototypes first...
949  */
950 static void	scsi_mach_init __P((struct ncr_softc *));
951        void	scsi_ienable __P((void));
952        void	scsi_idisable __P((void));
953        void	scsi_clr_ipend __P((void));
954        int	scsi_ipending __P((void));
955        void	scsi_dma_setup __P((SC_REQ *, u_int, u_char));
956        int	wrong_dma_range __P((SC_REQ *, struct dma_chain *));
957        int	poll_edma __P((SC_REQ *));
958        int	get_dma_result __P((SC_REQ *, u_long *));
959        int	can_access_5380 __P((void));
960 
961 /*
962  * Register access will be done through the following 2 function pointers.
963  */
964 static u_char	(*get_5380_reg) __P((u_short));
965 static void	(*set_5380_reg) __P((u_short, u_short));
966 
967 #define	GET_5380_REG	(*get_5380_reg)
968 #define	SET_5380_REG	(*set_5380_reg)
969 
970 static void
971 scsi_mach_init(sc)
972 struct ncr_softc	*sc;
973 {
974 	if (machineid & ATARI_FALCON) {
975 		get_5380_reg = get_falcon_5380_reg;
976 		set_5380_reg = set_falcon_5380_reg;
977 		scsi_falcon_init(sc);
978 	}
979 	else {
980 		get_5380_reg = get_tt_5380_reg;
981 		set_5380_reg = set_tt_5380_reg;
982 		scsi_tt_init(sc);
983 	}
984 }
985 
986 extern __inline__ void
987 scsi_ienable()
988 {
989 	if (machineid & ATARI_FALCON)
990 		scsi_falcon_ienable();
991 	else scsi_tt_ienable();
992 }
993 
994 extern __inline__ void
995 scsi_idisable()
996 {
997 	if (machineid & ATARI_FALCON)
998 		scsi_falcon_idisable();
999 	else scsi_tt_idisable();
1000 }
1001 
1002 extern __inline__ void
1003 scsi_clr_ipend()
1004 {
1005 	if (machineid & ATARI_FALCON)
1006 		scsi_falcon_clr_ipend();
1007 	else scsi_tt_clr_ipend();
1008 }
1009 
1010 extern __inline__ int
1011 scsi_ipending()
1012 {
1013 	if (machineid & ATARI_FALCON)
1014 		return(scsi_falcon_ipending());
1015 	else return (GET_TT_REG(NCR5380_DMSTAT) & SC_IRQ_SET);
1016 }
1017 
1018 extern __inline__ void
1019 scsi_dma_setup(reqp, phase, mbase)
1020 SC_REQ	*reqp;
1021 u_int	phase;
1022 u_char	mbase;
1023 {
1024 	if (machineid & ATARI_FALCON)
1025 		scsi_falcon_dmasetup(reqp, phase, mbase);
1026 	else scsi_tt_dmasetup(reqp, phase, mbase);
1027 }
1028 
1029 extern __inline__ int
1030 wrong_dma_range(reqp, dm)
1031 SC_REQ			*reqp;
1032 struct dma_chain	*dm;
1033 {
1034 	if (machineid & ATARI_FALCON)
1035 		return(falcon_wrong_dma_range(reqp, dm));
1036 	else return(tt_wrong_dma_range(reqp, dm));
1037 }
1038 
1039 extern __inline__ int
1040 poll_edma(reqp)
1041 SC_REQ	*reqp;
1042 {
1043 	if (machineid & ATARI_FALCON)
1044 		return(falcon_poll_edma(reqp));
1045 	else return(tt_poll_edma(reqp));
1046 }
1047 
1048 extern __inline__ int
1049 get_dma_result(reqp, bytes_left)
1050 SC_REQ	*reqp;
1051 u_long	*bytes_left;
1052 {
1053 	if (machineid & ATARI_FALCON)
1054 		return(falcon_get_dma_result(reqp, bytes_left));
1055 	else return(tt_get_dma_result(reqp, bytes_left));
1056 }
1057 
1058 extern __inline__ int
1059 can_access_5380()
1060 {
1061 	if (machineid & ATARI_FALCON)
1062 		return(falcon_can_access_5380());
1063 	return(1);
1064 }
1065 
1066 #define emulated_dma()		((machineid & ATARI_HADES) ? 1 : 0)
1067 
1068 /*
1069  * Locking stuff. All turns into NOP's on the TT.
1070  */
1071 #define	fair_to_keep_dma()	((machineid & ATARI_FALCON) ?		\
1072 						!st_dmawanted() : 1)
1073 #define	claimed_dma()		((machineid & ATARI_FALCON) ?		\
1074 						falcon_claimed_dma() : 1)
1075 #define reconsider_dma()	{					\
1076 					if(machineid & ATARI_FALCON)	\
1077 						falcon_reconsider_dma();\
1078 				}
1079 #endif /* defined(TT_SCSI) && defined(FALCON_SCSI) */
1080 
1081 /**********************************************
1082  * Functions present for both TT and Falcon.  *
1083  **********************************************/
1084 /*
1085  * Our autoconfig matching function
1086  */
1087 static int
1088 machine_match(struct device *pdp, void *match, void *auxp,
1089 						struct cfdriver *cd)
1090 {
1091 	static int	we_matched = 0; /* Only one unit	*/
1092 
1093 	if (strcmp(auxp, cd->cd_name) || we_matched)
1094 		return(0);
1095 
1096 	we_matched = 1;
1097 	return(1);
1098 }
1099 
1100 /*
1101  * Bounce buffer (de)allocation. Those buffers are gotten from the ST-mem
1102  * pool. Allocation here is both contiguous and in the lower 16Mb of
1103  * the address space. Thus being DMA-able for all controllers.
1104  */
1105 static u_char *
1106 alloc_bounceb(u_long len)
1107 {
1108 	void	*tmp;
1109 
1110 	return((u_char *)alloc_stmem(len, &tmp));
1111 }
1112 
1113 static void
1114 free_bounceb(u_char *bounceb)
1115 {
1116 	free_stmem(bounceb);
1117 }
1118 
1119 /*
1120  * 5380 interrupt.
1121  */
1122 void
1123 scsi_ctrl(int sr)
1124 {
1125 	if (GET_5380_REG(NCR5380_DMSTAT) & SC_IRQ_SET) {
1126 		scsi_idisable();
1127 		if (!BASEPRI(sr))
1128 			add_sicallback((si_farg)ncr_ctrl_intr,
1129 						(void *)cur_softc, 0);
1130 		else {
1131 			spl1();
1132 			ncr_ctrl_intr(cur_softc);
1133 			spl0();
1134 		}
1135 	}
1136 }
1137 
1138 /*
1139  * DMA controller interrupt
1140  */
1141 void
1142 scsi_dma(int sr)
1143 {
1144 	SC_REQ	*reqp;
1145 
1146 	if ((reqp = connected) && (reqp->dr_flag & DRIVER_IN_DMA)) {
1147 		scsi_idisable();
1148 		if (!BASEPRI(sr))
1149 			add_sicallback((si_farg)ncr_dma_intr,
1150 					(void *)cur_softc, 0);
1151 		else {
1152 			spl1();
1153 			ncr_dma_intr(cur_softc);
1154 			spl0();
1155 		}
1156 	}
1157 }
1158 
1159 /*
1160  * Last but not least... Include the general driver code
1161  */
1162 #include <atari/dev/ncr5380.c>
1163