xref: /netbsd-src/sys/arch/atari/dev/atari5380.c (revision 1b9578b8c2c1f848eeb16dabbfd7d1f0d9fdefbd)
1 /*	$NetBSD: atari5380.c,v 1.57 2011/06/05 06:33:42 tsutsui 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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: atari5380.c,v 1.57 2011/06/05 06:33:42 tsutsui Exp $");
30 
31 #include "opt_atariscsi.h"
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 <dev/scsipi/scsi_all.h>
39 #include <dev/scsipi/scsipi_all.h>
40 #include <dev/scsipi/scsi_message.h>
41 #include <dev/scsipi/scsiconf.h>
42 
43 #include <uvm/uvm_extern.h>
44 
45 #include <m68k/asm_single.h>
46 #include <m68k/cpu.h>
47 #include <m68k/cacheops.h>
48 
49 #include <atari/atari/stalloc.h>
50 
51 /*
52  * Include the driver definitions
53  */
54 #include <atari/dev/ncr5380reg.h>
55 
56 #include <machine/stdarg.h>
57 #include <machine/iomap.h>
58 #include <machine/mfp.h>
59 #include <machine/intr.h>
60 
61 #if defined(FALCON_SCSI)
62 #include <machine/dma.h>
63 #endif
64 
65 /*
66  * Set the various driver options
67  */
68 #define	NREQ		18	/* Size of issue queue			*/
69 #define	AUTO_SENSE	1	/* Automatically issue a request-sense 	*/
70 
71 #define	DRNAME		ncrscsi	/* used in various prints		*/
72 #undef	DBG_SEL			/* Show the selection process		*/
73 #undef	DBG_REQ			/* Show enqueued/ready requests		*/
74 #undef	DBG_ERR_RET		/* Show requests with != 0 return code	*/
75 #undef	DBG_NOWRITE		/* Do not allow writes to the targets	*/
76 #undef	DBG_PIO			/* Show the polled-I/O process		*/
77 #undef	DBG_INF			/* Show information transfer process	*/
78 #define	DBG_NOSTATIC		/* No static functions, all in DDB trace*/
79 #define	DBG_PID		15	/* Keep track of driver			*/
80 #define	REAL_DMA		/* Use DMA if sensible			*/
81 #if defined(FALCON_SCSI)
82 #define	REAL_DMA_POLL	1	/* 1: Poll for end of DMA-transfer	*/
83 #else
84 #define	REAL_DMA_POLL	0	/* 1: Poll for end of DMA-transfer	*/
85 #endif
86 #undef	USE_PDMA		/* Use special pdma-transfer function	*/
87 #define MIN_PHYS	65536	/*BARF!!!!*/
88 
89 /*
90  * Include more driver definitions
91  */
92 #include <atari/dev/ncr5380var.h>
93 
94 /*
95  * The atari specific driver options
96  */
97 #undef	NO_TTRAM_DMA		/* Do not use DMA to TT-ram. This	*/
98 				/*    fails on older atari's		*/
99 #define	ENABLE_NCR5380(sc)	cur_softc = sc;
100 
101 static uint8_t	*alloc_bounceb(u_long);
102 static void	free_bounceb(uint8_t *);
103 static int	machine_match(device_t, cfdata_t, void *, struct cfdriver *);
104 
105 void	scsi_ctrl(int);
106 void	scsi_dma(int);
107 
108 /*
109  * Functions that do nothing on the atari
110  */
111 #define	pdma_ready()		0
112 
113 #if defined(TT_SCSI)
114 
115 void	ncr5380_drq_intr(int);
116 
117 /*
118  * Define all the things we need of the DMA-controller
119  */
120 #define	SCSI_DMA	((struct scsi_dma *)AD_SCSI_DMA)
121 #define	SCSI_5380	((struct scsi_5380 *)AD_NCR5380)
122 
123 struct scsi_dma {
124 	volatile uint8_t	s_dma_ptr[8];	/* use only the odd bytes */
125 	volatile uint8_t	s_dma_cnt[8];	/* use only the odd bytes */
126 	volatile uint8_t	s_dma_res[4];	/* data residue register  */
127 	volatile uint8_t	s_dma_gap;	/* not used		  */
128 	volatile uint8_t	s_dma_ctrl;	/* control register	  */
129 	volatile uint8_t	s_dma_gap2;	/* not used		  */
130 	volatile uint8_t	s_hdma_ctrl;	/* Hades control register */
131 };
132 
133 static inline void set_scsi_dma(volatile uint8_t *, u_long);
134 static inline u_long get_scsi_dma(volatile uint8_t *);
135 
136 static inline void
137 set_scsi_dma(volatile uint8_t *addr, u_long val)
138 {
139 	volatile uint8_t *address;
140 
141 	address = addr + 1;
142 	__asm("movepl	%0, %1@(0)": :"d" (val), "a" (address));
143 }
144 
145 static inline u_long
146 get_scsi_dma(volatile uint8_t *addr)
147 {
148 	volatile uint8_t *address;
149 	u_long	nval;
150 
151 	address = addr + 1;
152 	__asm("movepl	%1@(0), %0": "=d" (nval) : "a" (address));
153 
154 	return nval;
155 }
156 
157 /*
158  * Defines for TT-DMA control register
159  */
160 #define	SD_BUSERR	0x80		/* 1 = transfer caused bus error*/
161 #define	SD_ZERO		0x40		/* 1 = byte counter is zero	*/
162 #define	SD_ENABLE	0x02		/* 1 = Enable DMA		*/
163 #define	SD_OUT		0x01		/* Direction: memory to SCSI	*/
164 #define	SD_IN		0x00		/* Direction: SCSI to memory	*/
165 
166 /*
167  * Defines for Hades-DMA control register
168  */
169 #define	SDH_BUSERR	0x02		/* 1 = Bus error		*/
170 #define SDH_EOP		0x01		/* 1 = Signal EOP on 5380	*/
171 #define	SDH_ZERO	0x40		/* 1 = Byte counter is zero	*/
172 
173 /*
174  * Define the 5380 register set
175  */
176 struct scsi_5380 {
177 	volatile uint8_t scsi_5380[16];	/* use only the odd bytes	*/
178 };
179 #endif /* TT_SCSI */
180 
181 /**********************************************
182  * Variables present for both TT and Falcon.  *
183  **********************************************/
184 
185 /*
186  * Softc of currently active controller (a bit of fake; we only have one)
187  */
188 static struct ncr_softc	*cur_softc;
189 
190 #if defined(TT_SCSI) && !defined(FALCON_SCSI)
191 /*
192  * We can be more efficient for some functions when only TT_SCSI is selected
193  */
194 #define	GET_5380_REG(rnum)	SCSI_5380->scsi_5380[(rnum << 1) | 1]
195 #define	SET_5380_REG(rnum,val)	(SCSI_5380->scsi_5380[(rnum << 1) | 1] = val)
196 
197 #define scsi_mach_init(sc)	scsi_tt_init(sc)
198 #define scsi_ienable()		scsi_tt_ienable()
199 #define scsi_idisable()		scsi_tt_idisable()
200 #define	scsi_clr_ipend()	scsi_tt_clr_ipend()
201 #define scsi_ipending()		(GET_5380_REG(NCR5380_DMSTAT) & SC_IRQ_SET)
202 #define scsi_dma_setup(r,p,m)	scsi_tt_dmasetup(r, p, m)
203 #define wrong_dma_range(r,d)	tt_wrong_dma_range(r, d)
204 #define poll_edma(reqp)		tt_poll_edma(reqp)
205 #define get_dma_result(r, b)	tt_get_dma_result(r, b)
206 #define	can_access_5380()	1
207 #define emulated_dma()		((machineid & ATARI_HADES) ? 1 : 0)
208 
209 #define fair_to_keep_dma()	1
210 #define claimed_dma()		1
211 #define reconsider_dma()
212 
213 #endif /* defined(TT_SCSI) && !defined(FALCON_SCSI) */
214 
215 #if defined(TT_SCSI)
216 
217 /*
218  * Prototype functions defined below
219  */
220 #ifdef NO_TTRAM_DMA
221 static int tt_wrong_dma_range(SC_REQ *, struct dma_chain *);
222 #endif
223 static void	scsi_tt_init(struct ncr_softc *);
224 static uint8_t	get_tt_5380_reg(u_short);
225 static void	set_tt_5380_reg(u_short, u_short);
226 static void	scsi_tt_dmasetup(SC_REQ *, u_int, uint8_t);
227 static int	tt_poll_edma(SC_REQ *);
228 static uint8_t	*ptov(SC_REQ *, u_long*);
229 static int	tt_get_dma_result(SC_REQ *, u_long *);
230 
231 void	scsi_tt_ienable(void);
232 void	scsi_tt_idisable(void);
233 void	scsi_tt_clr_ipend(void);
234 
235 /*
236  * Define these too, so we can use them locally...
237  */
238 #define	GET_TT_REG(rnum)	SCSI_5380->scsi_5380[(rnum << 1) | 1]
239 #define	SET_TT_REG(rnum,val)	(SCSI_5380->scsi_5380[(rnum << 1) | 1] = val)
240 
241 #ifdef NO_TTRAM_DMA
242 static int
243 tt_wrong_dma_range(SC_REQ *reqp, struct dma_chain *dm)
244 {
245 
246 	if (dm->dm_addr & 0xff000000) {
247 		reqp->dr_flag |= DRIVER_BOUNCING;
248 		return 1;
249 	}
250 	return 0;
251 }
252 #else
253 #define	tt_wrong_dma_range(reqp, dm)	0
254 #endif
255 
256 static void
257 scsi_tt_init(struct ncr_softc *sc)
258 {
259 
260 	/*
261 	 * Enable SCSI-related interrupts
262 	 */
263 	MFP2->mf_aer  |= 0x80;		/* SCSI IRQ goes HIGH!!!!!	*/
264 
265 	if (machineid & ATARI_TT) {
266 		/* SCSI-DMA interrupts		*/
267 		MFP2->mf_ierb |= IB_SCDM;
268 		MFP2->mf_iprb  = (uint8_t)~IB_SCDM;
269 		MFP2->mf_imrb |= IB_SCDM;
270 	} else if (machineid & ATARI_HADES) {
271 		SCSI_DMA->s_hdma_ctrl = 0;
272 
273 		if (intr_establish(2, AUTO_VEC, 0,
274 		    (hw_ifun_t)ncr5380_drq_intr, NULL) == NULL)
275 		panic("scsi_tt_init: Can't establish drq-interrupt");
276 	} else
277 		panic("scsi_tt_init: should not come here");
278 
279 	MFP2->mf_iera |= IA_SCSI;	/* SCSI-5380 interrupts		*/
280 	MFP2->mf_ipra  = (uint8_t)~IA_SCSI;
281 	MFP2->mf_imra |= IA_SCSI;
282 
283 	/*
284 	 * LWP: DMA transfers to TT-ram causes data to be garbled
285 	 * without notice on some TT-mainboard revisions.
286 	 * If programs generate mysterious Segmentations faults,
287 	 * try enabling NO_TTRAM_DMA.
288 	 */
289 #ifdef NO_TTRAM_DMA
290 	printf(": DMA to TT-RAM is disabled!");
291 #endif
292 }
293 
294 static uint8_t
295 get_tt_5380_reg(u_short rnum)
296 {
297 
298 	return SCSI_5380->scsi_5380[(rnum << 1) | 1];
299 }
300 
301 static void
302 set_tt_5380_reg(u_short rnum, u_short val)
303 {
304 
305 	SCSI_5380->scsi_5380[(rnum << 1) | 1] = val;
306 }
307 
308 static inline void
309 scsi_tt_ienable(void)
310 {
311 
312 	if (machineid & ATARI_TT)
313 		single_inst_bset_b(MFP2->mf_imrb, IB_SCDM);
314 	single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
315 }
316 
317 static inline void
318 scsi_tt_idisable(void)
319 {
320 
321 	if (machineid & ATARI_TT)
322 		single_inst_bclr_b(MFP2->mf_imrb, IB_SCDM);
323 	single_inst_bclr_b(MFP2->mf_imra, IA_SCSI);
324 }
325 
326 static inline void
327 scsi_tt_clr_ipend(void)
328 {
329 	int tmp;
330 
331 	SCSI_DMA->s_dma_ctrl = 0;
332 	tmp = GET_TT_REG(NCR5380_IRCV);
333 	if (machineid & ATARI_TT)
334 		MFP2->mf_iprb = (uint8_t)~IB_SCDM;
335 	MFP2->mf_ipra = (uint8_t)~IA_SCSI;
336 
337 	/*
338 	 * Remove interrupts already scheduled.
339 	 */
340 	rem_sicallback((si_farg)ncr_ctrl_intr);
341 	rem_sicallback((si_farg)ncr_dma_intr);
342 }
343 
344 static void
345 scsi_tt_dmasetup(SC_REQ *reqp, u_int phase, uint8_t mode)
346 {
347 
348 	if (PH_IN(phase)) {
349 		SCSI_DMA->s_dma_ctrl = SD_IN;
350 		if (machineid & ATARI_HADES)
351 			SCSI_DMA->s_hdma_ctrl &= ~(SDH_BUSERR|SDH_EOP);
352 		set_scsi_dma(SCSI_DMA->s_dma_ptr, reqp->dm_cur->dm_addr);
353 		set_scsi_dma(SCSI_DMA->s_dma_cnt, reqp->dm_cur->dm_count);
354 		SET_TT_REG(NCR5380_ICOM, 0);
355 		SET_TT_REG(NCR5380_MODE, mode);
356 		SCSI_DMA->s_dma_ctrl = SD_ENABLE;
357 		SET_TT_REG(NCR5380_IRCV, 0);
358 	} else {
359 		SCSI_DMA->s_dma_ctrl = SD_OUT;
360 		if (machineid & ATARI_HADES)
361 			SCSI_DMA->s_hdma_ctrl &= ~(SDH_BUSERR|SDH_EOP);
362 		set_scsi_dma(SCSI_DMA->s_dma_ptr, reqp->dm_cur->dm_addr);
363 		set_scsi_dma(SCSI_DMA->s_dma_cnt, reqp->dm_cur->dm_count);
364 		SET_TT_REG(NCR5380_MODE, mode);
365 		SET_TT_REG(NCR5380_ICOM, SC_ADTB);
366 		SET_TT_REG(NCR5380_DMSTAT, 0);
367 		SCSI_DMA->s_dma_ctrl = SD_ENABLE|SD_OUT;
368 	}
369 }
370 
371 static int
372 tt_poll_edma(SC_REQ *reqp)
373 {
374 	uint8_t	dmstat, dmastat;
375 	int	timeout = 9000; /* XXX */
376 
377 	/*
378 	 * We wait here until the DMA has finished. This can be
379 	 * achieved by checking the following conditions:
380 	 *   - 5380:
381 	 *	- End of DMA flag is set
382 	 *	- We lost BSY (error!!)
383 	 *	- A phase mismatch has occurred (partial transfer)
384 	 *   - DMA-controller:
385 	 *	- A bus error occurred (Kernel error!!)
386 	 *	- All bytes are transferred
387 	 * If one of the terminating conditions was met, we call
388 	 * 'dma_ready' to check errors and perform the bookkeeping.
389 	 */
390 
391 	scsi_tt_idisable();
392 	for (;;) {
393 		delay(20);
394 		if (--timeout <= 0) {
395 			ncr_tprint(reqp, "timeout on polled transfer\n");
396 			reqp->xs->error = XS_TIMEOUT;
397 			scsi_tt_ienable();
398 			return 0;
399 		}
400 		dmstat  = GET_TT_REG(NCR5380_DMSTAT);
401 
402 		if ((machineid & ATARI_HADES) && (dmstat & SC_DMA_REQ)) {
403 			ncr5380_drq_intr(1);
404 			dmstat  = GET_TT_REG(NCR5380_DMSTAT);
405 		}
406 
407 		dmastat = SCSI_DMA->s_dma_ctrl;
408 		if (dmstat & (SC_END_DMA|SC_BSY_ERR|SC_IRQ_SET))
409 			break;
410 		if ((dmstat & SC_PHS_MTCH) == 0)
411 			break;
412 		if (dmastat & (SD_BUSERR|SD_ZERO))
413 			break;
414 	}
415 	scsi_tt_ienable();
416 	return 1;
417 }
418 
419 /*
420  * Convert physical DMA address to a virtual address.
421  */
422 static uint8_t *
423 ptov(SC_REQ *reqp, u_long *phaddr)
424 {
425 	struct dma_chain	*dm;
426 	uint8_t			*vaddr;
427 
428 	dm = reqp->dm_chain;
429 	vaddr = reqp->xdata_ptr;
430 	for (; dm < reqp->dm_cur; dm++)
431 		vaddr += dm->dm_count;
432 	vaddr += (u_long)phaddr - dm->dm_addr;
433 	return vaddr;
434 }
435 
436 static int
437 tt_get_dma_result(SC_REQ *reqp, u_long *bytes_left)
438 {
439 	int	dmastat, dmstat;
440 	uint8_t	*byte_p;
441 	u_long	leftover;
442 
443 	dmastat = SCSI_DMA->s_dma_ctrl;
444 	dmstat  = GET_TT_REG(NCR5380_DMSTAT);
445 	leftover = get_scsi_dma(SCSI_DMA->s_dma_cnt);
446 	byte_p = (uint8_t *)get_scsi_dma(SCSI_DMA->s_dma_ptr);
447 
448 	if (dmastat & SD_BUSERR) {
449 		/*
450 		 * The DMA-controller seems to access 8 bytes beyond
451 		 * it's limits on output. Therefore check also the byte
452 		 * count. If it's zero, ignore the bus error.
453 		 */
454 		if (leftover != 0) {
455 			ncr_tprint(reqp,
456 			    "SCSI-DMA buserror - accessing 0x%x\n", byte_p);
457 			reqp->xs->error = XS_DRIVER_STUFFUP;
458 		}
459 	}
460 
461 	/*
462 	 * We handle the following special condition below:
463 	 *  -- The device disconnects in the middle of a write operation --
464 	 * In this case, the 5380 has already pre-fetched the next byte from
465 	 * the DMA-controller before the phase mismatch occurs. Therefore,
466 	 * leftover is 1 too low.
467 	 * This does not always happen! Therefore, we only do this when
468 	 * leftover is odd. This assumes that DMA transfers are _even_! This
469 	 * is normally the case on disks and types but might not always be.
470 	 * XXX: Check if ACK is consistently high on these occasions LWP
471 	 */
472 	if ((leftover & 1) &&
473 	    (dmstat & SC_PHS_MTCH) == 0 && PH_OUT(reqp->phase))
474 		leftover++;
475 
476 	/*
477 	 * Check if there are some 'restbytes' left in the DMA-controller.
478 	 */
479 	if ((machineid & ATARI_TT) &&
480 	    ((u_long)byte_p & 3) && PH_IN(reqp->phase)) {
481 		uint8_t	*p;
482 		volatile uint8_t *q;
483 
484 		p = ptov(reqp, (u_long *)((u_long)byte_p & ~3));
485 		q = SCSI_DMA->s_dma_res;
486 		switch ((u_long)byte_p & 3) {
487 			case 3: *p++ = *q++;
488 			case 2: *p++ = *q++;
489 			case 1: *p++ = *q++;
490 		}
491 	}
492 	*bytes_left = leftover;
493 	return (dmastat & (SD_BUSERR|SD_ZERO)) ? 1 : 0;
494 }
495 
496 static uint8_t *dma_ptr;
497 void
498 ncr5380_drq_intr(int poll)
499 {
500 	extern int *nofault;
501 	label_t faultbuf;
502 	int write;
503 	u_long count;
504 	volatile uint8_t *data_p = (volatile uint8_t *)(stio_addr + 0x741);
505 
506 	/*
507 	 * Block SCSI interrupts while emulating DMA. They come
508 	 * at a higher priority.
509 	 */
510 	single_inst_bclr_b(MFP2->mf_imra, IA_SCSI);
511 
512 	/*
513 	 * Setup for a possible bus error caused by SCSI controller
514 	 * switching out of DATA-IN/OUT before we're done with the
515 	 * current transfer.
516 	 */
517 	nofault = (int *)&faultbuf;
518 
519 	if (setjmp((label_t *) nofault)) {
520 		u_long cnt, tmp;
521 
522 		PID("drq berr");
523 		nofault = (int *)0;
524 
525 		/*
526 		 * Determine number of bytes transferred
527 		 */
528 		cnt = (u_long)dma_ptr - get_scsi_dma(SCSI_DMA->s_dma_ptr);
529 
530 		if (cnt != 0) {
531 			/*
532 			 * Update the DMA pointer/count fields
533 			 */
534 			set_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)dma_ptr);
535 			tmp = get_scsi_dma(SCSI_DMA->s_dma_cnt);
536 			set_scsi_dma(SCSI_DMA->s_dma_cnt, tmp - cnt);
537 
538 			if (tmp > cnt) {
539 				/*
540 				 * Still more to transfer
541 				 */
542 				if (!poll)
543 					single_inst_bset_b(MFP2->mf_imra,
544 					    IA_SCSI);
545 				return;
546 			}
547 
548 			/*
549 			 * Signal EOP to 5380
550 			 */
551 			SCSI_DMA->s_hdma_ctrl |= SDH_EOP;
552 		} else {
553 			nofault = (int *)&faultbuf;
554 
555 			/*
556 			 * Try to figure out if the byte-count was
557 			 * zero because there was no (more) data or
558 			 * because the dma_ptr is bogus.
559 			 */
560 			if (setjmp((label_t *) nofault)) {
561 				/*
562 				 * Set the bus-error bit
563 				 */
564 				SCSI_DMA->s_hdma_ctrl |= SDH_BUSERR;
565 			}
566 			__asm volatile ("tstb	%0@(0)": : "a" (dma_ptr));
567 			nofault = (int *)0;
568 		}
569 
570 		/*
571 		 * Schedule an interrupt
572 		 */
573 		if (!poll && (SCSI_DMA->s_dma_ctrl & SD_ENABLE))
574 			add_sicallback((si_farg)ncr_dma_intr,
575 			    (void *)cur_softc, 0);
576 
577 		/*
578 		 * Clear DMA-mode
579 		 */
580 		SCSI_DMA->s_dma_ctrl &= ~SD_ENABLE;
581 		if (!poll)
582 			single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
583 
584 		return;
585 	}
586 
587 	write = (SCSI_DMA->s_dma_ctrl & SD_OUT) ? 1 : 0;
588 #if DBG_PID
589 	if (write) {
590 		PID("drq (in)");
591 	} else {
592 		PID("drq (out)");
593 	}
594 #endif
595 
596 	count = get_scsi_dma(SCSI_DMA->s_dma_cnt);
597 	dma_ptr = (uint8_t *)get_scsi_dma(SCSI_DMA->s_dma_ptr);
598 
599 	/*
600 	 * Keep pushing bytes until we're done or a bus-error
601 	 * signals that the SCSI controller is not ready.
602 	 * NOTE: I tried some optimalizations in these loops,
603 	 *       but they had no effect on transfer speed.
604 	 */
605 	if (write) {
606 		while (count--) {
607 			*data_p = *dma_ptr++;
608 		}
609 	} else {
610 		while (count--) {
611 			*dma_ptr++ = *data_p;
612 		}
613 	}
614 
615 	/*
616 	 * OK.  No bus error occurred above.  Clear the nofault flag
617 	 * so we no longer short-circuit bus errors.
618 	 */
619 	nofault = (int *)0;
620 
621 	/*
622 	 * Schedule an interrupt
623 	 */
624 	if (!poll && (SCSI_DMA->s_dma_ctrl & SD_ENABLE))
625 		add_sicallback((si_farg)ncr_dma_intr, (void *)cur_softc, 0);
626 
627 	/*
628 	 * Clear DMA-mode
629 	 */
630 	SCSI_DMA->s_dma_ctrl &= ~SD_ENABLE;
631 
632 	/*
633 	 * Update the DMA 'registers' to reflect that all bytes
634 	 * have been transfered and tell this to the 5380 too.
635 	 */
636 	set_scsi_dma(SCSI_DMA->s_dma_ptr, (u_long)dma_ptr);
637 	set_scsi_dma(SCSI_DMA->s_dma_cnt, 0);
638 	SCSI_DMA->s_hdma_ctrl |= SDH_EOP;
639 
640 	PID("end drq");
641 	if (!poll)
642 		single_inst_bset_b(MFP2->mf_imra, IA_SCSI);
643 
644 }
645 
646 #endif /* defined(TT_SCSI) */
647 
648 #if defined(FALCON_SCSI) && !defined(TT_SCSI)
649 
650 #define	GET_5380_REG(rnum)	get_falcon_5380_reg(rnum)
651 #define	SET_5380_REG(rnum,val)	set_falcon_5380_reg(rnum, val)
652 #define scsi_mach_init(sc)	scsi_falcon_init(sc)
653 #define scsi_ienable()		scsi_falcon_ienable()
654 #define scsi_idisable()		scsi_falcon_idisable()
655 #define	scsi_clr_ipend()	scsi_falcon_clr_ipend()
656 #define	scsi_ipending()		scsi_falcon_ipending()
657 #define scsi_dma_setup(r,p,m)	scsi_falcon_dmasetup(r, p, m)
658 #define wrong_dma_range(r,d)	falcon_wrong_dma_range(r, d)
659 #define poll_edma(reqp)		falcon_poll_edma(reqp)
660 #define get_dma_result(r, b)	falcon_get_dma_result(r, b)
661 #define	can_access_5380()	falcon_can_access_5380()
662 #define	emulated_dma()		0
663 
664 #define fair_to_keep_dma()	(!st_dmawanted())
665 #define claimed_dma()		falcon_claimed_dma()
666 #define reconsider_dma()	falcon_reconsider_dma()
667 
668 #endif /* defined(FALCON_SCSI) && !defined(TT_SCSI) */
669 
670 #if defined(FALCON_SCSI)
671 
672 /*
673  * Prototype functions defined below
674  */
675 static void	scsi_falcon_init(struct ncr_softc *);
676 static uint8_t	get_falcon_5380_reg(u_short);
677 static void	set_falcon_5380_reg(u_short, u_short);
678 static int	falcon_wrong_dma_range(SC_REQ *, struct dma_chain *);
679 static void	fal1_dma(u_int, u_int, SC_REQ *);
680 static void	scsi_falcon_dmasetup(SC_REQ  *, u_int, uint8_t);
681 static int	falcon_poll_edma(SC_REQ  *);
682 static int	falcon_get_dma_result(SC_REQ  *, u_long *);
683 
684 int	falcon_can_access_5380(void);
685 void	scsi_falcon_clr_ipend(void);
686 void	scsi_falcon_idisable(void);
687 void	scsi_falcon_ienable(void);
688 int	scsi_falcon_ipending(void);
689 int	falcon_claimed_dma(void);
690 void	falcon_reconsider_dma(void);
691 
692 static void
693 scsi_falcon_init(struct ncr_softc *sc)
694 {
695 
696 	/*
697 	 * Enable disk related interrupts
698 	 */
699 	MFP->mf_ierb  |= IB_DINT;
700 	MFP->mf_iprb   = (uint8_t)~IB_DINT;
701 	MFP->mf_imrb  |= IB_DINT;
702 }
703 
704 static uint8_t
705 get_falcon_5380_reg(u_short rnum)
706 {
707 
708 	DMA->dma_mode = DMA_SCSI + rnum;
709 	return DMA->dma_data;
710 }
711 
712 static void
713 set_falcon_5380_reg(u_short rnum, u_short val)
714 {
715 
716 	DMA->dma_mode = DMA_SCSI + rnum;
717 	DMA->dma_data = val;
718 }
719 
720 static inline void
721 scsi_falcon_ienable(void)
722 {
723 
724 	single_inst_bset_b(MFP->mf_imrb, IB_DINT);
725 }
726 
727 static inline void
728 scsi_falcon_idisable(void)
729 {
730 
731 	single_inst_bclr_b(MFP->mf_imrb, IB_DINT);
732 }
733 
734 static inline void
735 scsi_falcon_clr_ipend(void)
736 {
737 	int tmp;
738 
739 	tmp = get_falcon_5380_reg(NCR5380_IRCV);
740 	rem_sicallback((si_farg)ncr_ctrl_intr);
741 }
742 
743 static inline int
744 scsi_falcon_ipending(void)
745 {
746 
747 	if (connected && (connected->dr_flag & DRIVER_IN_DMA)) {
748 		/*
749 		 *  XXX: When DMA is running, we are only allowed to
750 		 *       check the 5380 when DMA _might_ be finished.
751 		 */
752 		if (MFP->mf_gpip & IO_DINT)
753 			/* XXX: Actually: we're not allowed to check */
754 			return 0;
755 
756 		/* LWP: 28-06, must be a DMA interrupt! should the
757 		 * ST-DMA unit be taken out of DMA mode?????
758 		 */
759 		DMA->dma_mode = 0x90;
760 
761 	}
762 	return get_falcon_5380_reg(NCR5380_DMSTAT) & SC_IRQ_SET;
763 }
764 
765 static int
766 falcon_wrong_dma_range(SC_REQ *reqp, struct dma_chain *dm)
767 {
768 
769 	/*
770 	 * Do not allow chains yet! See also comment with
771 	 * falcon_poll_edma() !!!
772 	 */
773 	if (((dm - reqp->dm_chain) > 0) || (dm->dm_addr & 0xff000000)) {
774 		reqp->dr_flag |= DRIVER_BOUNCING;
775 		return 1;
776 	}
777 	/*
778 	 * Never allow DMA to happen on a Falcon when the transfer
779 	 * size is no multiple of 512. This is the transfer unit of the
780 	 * ST DMA-controller.
781 	 */
782 	if (dm->dm_count & 511)
783 		return 1;
784 	return 0;
785 }
786 
787 static	int falcon_lock = 0;
788 
789 static inline int
790 falcon_claimed_dma(void)
791 {
792 
793 	if (falcon_lock != DMA_LOCK_GRANT) {
794 		if (falcon_lock == DMA_LOCK_REQ) {
795 			/*
796 			 * DMA access is being claimed.
797 			 */
798 			return 0;
799 		}
800 		if (st_dmagrab((dma_farg)ncr_ctrl_intr, (dma_farg)run_main,
801 		    cur_softc, &falcon_lock, 1) == 0)
802 			return 0;
803 	}
804 	return 1;
805 }
806 
807 static inline void
808 falcon_reconsider_dma(void)
809 {
810 
811 	if (falcon_lock && (connected == NULL) && (discon_q == NULL)) {
812 		/*
813 		 * No need to keep DMA locked by us as we are not currently
814 		 * connected and no disconnected jobs are pending.
815 		 */
816 		rem_sicallback((si_farg)ncr_ctrl_intr);
817 		st_dmafree(cur_softc, &falcon_lock);
818 	}
819 
820 	if (!falcon_lock && (issue_q != NULL)) {
821 		/*
822 		 * We must (re)claim DMA access as there are jobs
823 		 * waiting in the issue queue.
824 		 */
825 		st_dmagrab((dma_farg)ncr_ctrl_intr, (dma_farg)run_main,
826 		    cur_softc, &falcon_lock, 0);
827 	}
828 }
829 
830 static void
831 fal1_dma(u_int dir, u_int nsects, SC_REQ *reqp)
832 {
833 
834 	dir <<= 8;
835 	st_dmaaddr_set((void *)reqp->dm_cur->dm_addr);
836 	DMA->dma_mode = 0x90 | dir;
837 	DMA->dma_mode = 0x90 | (dir ^ DMA_WRBIT);
838 	DMA->dma_mode = 0x90 | dir;
839 	DMA->dma_data = nsects;
840 	delay(2);	/* _really_ needed (Thomas Gerner) */
841 	DMA->dma_mode = 0x10 | dir;
842 }
843 
844 static void
845 scsi_falcon_dmasetup(SC_REQ *reqp, u_int phase, uint8_t mode)
846 {
847 	int nsects = reqp->dm_cur->dm_count / 512; /* XXX */
848 
849 	/*
850 	 * XXX: We should probably clear the fifo before putting the
851 	 *      5380 into DMA-mode.
852 	 */
853 	if (PH_IN(phase)) {
854 		set_falcon_5380_reg(NCR5380_ICOM, 0);
855 		set_falcon_5380_reg(NCR5380_MODE, mode);
856 		set_falcon_5380_reg(NCR5380_IRCV, 0);
857 		fal1_dma(0, nsects, reqp);
858 	} else {
859 		set_falcon_5380_reg(NCR5380_MODE, mode);
860 		set_falcon_5380_reg(NCR5380_ICOM, SC_ADTB);
861 		set_falcon_5380_reg(NCR5380_DMSTAT, 0);
862 		fal1_dma(1, nsects, reqp);
863 	}
864 }
865 
866 static int
867 falcon_poll_edma(SC_REQ *reqp)
868 {
869 	int timeout = 9000; /* XXX */
870 
871 	/*
872 	 * Because of the Falcon hardware, it is impossible to reach
873 	 * the 5380 while doing DMA-transfers. So we have to rely on
874 	 * the interrupt line to determine if DMA-has finished. the
875 	 * DMA-controller itself will never fire an interrupt. This means
876 	 * that 'broken-up' DMA transfers are not (yet) possible on the
877 	 * Falcon.
878 	 */
879 	for (;;) {
880 		delay(20);
881 		if (--timeout <= 0) {
882 			ncr_tprint(reqp, "Timeout on polled transfer\n");
883 			reqp->xs->error = XS_TIMEOUT;
884 			return 0;
885 		}
886 		if ((MFP->mf_gpip & IO_DINT) == 0)
887 			break;
888 	}
889 	return 1;
890 }
891 
892 static int
893 falcon_get_dma_result(SC_REQ *reqp, u_long *bytes_left)
894 {
895 	int	rv = 0;
896 	int	st_dmastat;
897 	u_long	bytes_done;
898 
899 	/*
900 	 * Select sector counter register first (See Atari docu.)
901 	 */
902 	DMA->dma_mode = 0x90;
903 	if (!(st_dmastat = DMA->dma_stat) & 0x01) {
904 		/*
905 		 * Misc. DMA-error according to Atari...
906 		 */
907 		ncr_tprint(reqp, "Unknow ST-SCSI error near 0x%x\n",
908 		    st_dmaaddr_get());
909 		reqp->xs->error = XS_DRIVER_STUFFUP;
910 		rv = 1;
911 	}
912 	/*
913 	 * Because we NEVER start DMA on the Falcon when the data size
914 	 * is not a multiple of 512 bytes, we can safely round down the
915 	 * byte count on writes. We need to because in case of a disconnect,
916 	 * the DMA has already prefetched the next couple of bytes.
917 	 * On read, these byte counts are an error. They are logged and
918 	 * should be handled by the mi-part of the driver.
919 	 * NOTE: We formerly did this by using the 'byte-count-zero' bit
920 	 *       of the DMA controller, but this didn't seem to work???
921          *       [lwp 29/06/96]
922 	 */
923 	bytes_done = st_dmaaddr_get() - reqp->dm_cur->dm_addr;
924 	if (bytes_done & 511) {
925 		if (PH_IN(reqp->phase)) {
926 			ncr_tprint(reqp, "Byte count on read not a multiple "
927 			    "of 512 (%ld)\n", bytes_done);
928 		}
929 		bytes_done &= ~511;
930 	}
931 	if ((*bytes_left = reqp->dm_cur->dm_count - bytes_done) == 0)
932 		rv = 1;
933 	return rv;
934 }
935 
936 static int
937 falcon_can_access_5380()
938 {
939 
940 	if (connected && (connected->dr_flag & DRIVER_IN_DMA) &&
941 	    (MFP->mf_gpip & IO_DINT))
942 		return 0;
943 	return 1;
944 }
945 
946 #endif /* defined(FALCON_SCSI) */
947 
948 #if defined(TT_SCSI) && defined(FALCON_SCSI)
949 /*
950  * Define some functions to support _both_ TT and Falcon SCSI
951  */
952 
953 /*
954  * The prototypes first...
955  */
956 static void	scsi_mach_init(struct ncr_softc *);
957 
958 void	scsi_ienable(void);
959 void	scsi_idisable(void);
960 void	scsi_clr_ipend(void);
961 int	scsi_ipending(void);
962 void	scsi_dma_setup(SC_REQ *, u_int, uint8_t);
963 int	wrong_dma_range(SC_REQ *, struct dma_chain *);
964 int	poll_edma(SC_REQ *);
965 int	get_dma_result(SC_REQ *, u_long *);
966 int	can_access_5380(void);
967 
968 /*
969  * Register access will be done through the following 2 function pointers.
970  */
971 static uint8_t	(*get_5380_reg)(u_short);
972 static void	(*set_5380_reg)(u_short, u_short);
973 
974 #define	GET_5380_REG	(*get_5380_reg)
975 #define	SET_5380_REG	(*set_5380_reg)
976 
977 static void
978 scsi_mach_init(struct ncr_softc *sc)
979 {
980 
981 	if (machineid & ATARI_FALCON) {
982 		get_5380_reg = get_falcon_5380_reg;
983 		set_5380_reg = set_falcon_5380_reg;
984 		scsi_falcon_init(sc);
985 	} else {
986 		get_5380_reg = get_tt_5380_reg;
987 		set_5380_reg = set_tt_5380_reg;
988 		scsi_tt_init(sc);
989 	}
990 }
991 
992 static inline void
993 scsi_ienable(void)
994 {
995 
996 	if (machineid & ATARI_FALCON)
997 		scsi_falcon_ienable();
998 	else
999 		scsi_tt_ienable();
1000 }
1001 
1002 static inline void
1003 scsi_idisable(void)
1004 {
1005 
1006 	if (machineid & ATARI_FALCON)
1007 		scsi_falcon_idisable();
1008 	else
1009 		scsi_tt_idisable();
1010 }
1011 
1012 static inline void
1013 scsi_clr_ipend(void)
1014 {
1015 
1016 	if (machineid & ATARI_FALCON)
1017 		scsi_falcon_clr_ipend();
1018 	else
1019 		scsi_tt_clr_ipend();
1020 }
1021 
1022 static inline int
1023 scsi_ipending(void)
1024 {
1025 
1026 	if (machineid & ATARI_FALCON)
1027 		return scsi_falcon_ipending();
1028 	else
1029 		return GET_TT_REG(NCR5380_DMSTAT) & SC_IRQ_SET;
1030 }
1031 
1032 static inline void
1033 scsi_dma_setup(SC_REQ *reqp, u_int phase, uint8_t mbase)
1034 {
1035 
1036 	if (machineid & ATARI_FALCON)
1037 		scsi_falcon_dmasetup(reqp, phase, mbase);
1038 	else
1039 		scsi_tt_dmasetup(reqp, phase, mbase);
1040 }
1041 
1042 static inline int
1043 wrong_dma_range(SC_REQ *reqp, struct dma_chain *dm)
1044 {
1045 
1046 	if (machineid & ATARI_FALCON)
1047 		return falcon_wrong_dma_range(reqp, dm);
1048 	else
1049 		return tt_wrong_dma_range(reqp, dm);
1050 }
1051 
1052 static inline int
1053 poll_edma(SC_REQ *reqp)
1054 {
1055 
1056 	if (machineid & ATARI_FALCON)
1057 		return falcon_poll_edma(reqp);
1058 	else
1059 		return tt_poll_edma(reqp);
1060 }
1061 
1062 static inline int
1063 get_dma_result(SC_REQ *reqp, u_long *bytes_left)
1064 {
1065 
1066 	if (machineid & ATARI_FALCON)
1067 		return falcon_get_dma_result(reqp, bytes_left);
1068 	else
1069 		return tt_get_dma_result(reqp, bytes_left);
1070 }
1071 
1072 static inline int
1073 can_access_5380(void)
1074 {
1075 
1076 	if (machineid & ATARI_FALCON)
1077 		return falcon_can_access_5380();
1078 	return 1;
1079 }
1080 
1081 #define emulated_dma()		((machineid & ATARI_HADES) ? 1 : 0)
1082 
1083 /*
1084  * Locking stuff. All turns into NOP's on the TT.
1085  */
1086 #define	fair_to_keep_dma()						\
1087 	((machineid & ATARI_FALCON) ? !st_dmawanted() : 1)
1088 #define	claimed_dma()							\
1089 	((machineid & ATARI_FALCON) ? falcon_claimed_dma() : 1)
1090 #define reconsider_dma()						\
1091 	do {								\
1092 		if (machineid & ATARI_FALCON)				\
1093 			falcon_reconsider_dma();			\
1094 	} while (/* CONSTCOND */ 0)
1095 #endif /* defined(TT_SCSI) && defined(FALCON_SCSI) */
1096 
1097 /**********************************************
1098  * Functions present for both TT and Falcon.  *
1099  **********************************************/
1100 /*
1101  * Our autoconfig matching function
1102  */
1103 static int
1104 machine_match(device_t parent, cfdata_t cf, void *aux, struct cfdriver *cd)
1105 {
1106 	static int we_matched = 0; /* Only one unit	*/
1107 
1108 	if (strcmp(aux, cd->cd_name) || we_matched)
1109 		return 0;
1110 
1111 	we_matched = 1;
1112 	return 1;
1113 }
1114 
1115 /*
1116  * Bounce buffer (de)allocation. Those buffers are gotten from the ST-mem
1117  * pool. Allocation here is both contiguous and in the lower 16Mb of
1118  * the address space. Thus being DMA-able for all controllers.
1119  */
1120 static uint8_t *
1121 alloc_bounceb(u_long len)
1122 {
1123 	void *tmp;
1124 
1125 	return (uint8_t *)alloc_stmem(len, &tmp);
1126 }
1127 
1128 static void
1129 free_bounceb(uint8_t *bounceb)
1130 {
1131 
1132 	free_stmem(bounceb);
1133 }
1134 
1135 /*
1136  * 5380 interrupt.
1137  */
1138 void
1139 scsi_ctrl(int sr)
1140 {
1141 
1142 	if (GET_5380_REG(NCR5380_DMSTAT) & SC_IRQ_SET) {
1143 		scsi_idisable();
1144 		add_sicallback((si_farg)ncr_ctrl_intr, (void *)cur_softc, 0);
1145 	}
1146 }
1147 
1148 /*
1149  * DMA controller interrupt
1150  */
1151 void
1152 scsi_dma(int sr)
1153 {
1154 	SC_REQ	*reqp;
1155 
1156 	if ((reqp = connected) && (reqp->dr_flag & DRIVER_IN_DMA)) {
1157 		scsi_idisable();
1158 		add_sicallback((si_farg)ncr_dma_intr, (void *)cur_softc, 0);
1159 	}
1160 }
1161 
1162 /*
1163  * Last but not least... Include the general driver code
1164  */
1165 #include <atari/dev/ncr5380.c>
1166