xref: /netbsd-src/sys/arch/amiga/dev/efa.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /*	$NetBSD: efa.c,v 1.15 2017/10/20 07:06:06 jdolecek Exp $ */
2 
3 /*-
4  * Copyright (c) 2011 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Radoslaw Kujawa.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Driver for FastATA 1200 EIDE controller, manufactured by ELBOX Computer.
34  *
35  * Gayle-related stuff inspired by wdc_amiga.c written by Michael L. Hitch
36  * and Aymeric Vincent.
37  */
38 
39 #include <sys/cdefs.h>
40 
41 #include <sys/types.h>
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/malloc.h>
45 #include <sys/device.h>
46 #include <sys/bus.h>
47 #include <sys/proc.h>
48 #include <sys/kernel.h>
49 #include <sys/kthread.h>
50 
51 #include <machine/cpu.h>
52 #include <machine/intr.h>
53 #include <sys/bswap.h>
54 
55 #include <amiga/amiga/cia.h>
56 #include <amiga/amiga/custom.h>
57 #include <amiga/amiga/device.h>
58 #include <amiga/amiga/gayle.h>
59 #include <amiga/dev/zbusvar.h>
60 
61 #include <dev/ata/atavar.h>
62 #include <dev/ic/wdcvar.h>
63 
64 #include <amiga/dev/efareg.h>
65 #include <amiga/dev/efavar.h>
66 
67 #define EFA_32BIT_IO 1
68 /* #define EFA_NO_INTR 1 */
69 /* #define EFA_DEBUG 1 */
70 
71 int		efa_probe(device_t, cfdata_t, void *);
72 void		efa_attach(device_t, device_t, void *);
73 int		efa_intr(void *);
74 int		efa_intr_soft(void *arg);
75 static void	efa_set_opts(struct efa_softc *sc);
76 static bool	efa_mapbase(struct efa_softc *sc);
77 static bool	efa_mapreg_gayle(struct efa_softc *sc);
78 static bool	efa_mapreg_native(struct efa_softc *sc);
79 static void	efa_fata_subregion_pio0(struct wdc_regs *wdr_fata);
80 static void	efa_fata_subregion_pion(struct wdc_regs *wdr_fata, bool data32);
81 static void	efa_setup_channel(struct ata_channel *chp);
82 static void	efa_attach_channel(struct efa_softc *sc, int i);
83 static void	efa_select_regset(struct efa_softc *sc, int chnum,
84 		    uint8_t piomode);
85 static void	efa_poll_kthread(void *arg);
86 static bool	efa_compare_status(void);
87 #ifdef EFA_DEBUG
88 static void	efa_debug_print_regmapping(struct wdc_regs *wdr_fata);
89 #endif /* EFA_DEBUG */
90 
91 CFATTACH_DECL_NEW(efa, sizeof(struct efa_softc),
92     efa_probe, efa_attach, NULL, NULL);
93 
94 #define PIO_NSUPP		0xFFFFFFFF
95 
96 static const bus_addr_t		pio_offsets[] =
97     { FATA1_PIO0_OFF, PIO_NSUPP, PIO_NSUPP, FATA1_PIO3_OFF, FATA1_PIO4_OFF,
98       FATA1_PIO5_OFF };
99 static const unsigned int	wdr_offsets_pio0[] =
100     { FATA1_PIO0_OFF_DATA, FATA1_PIO0_OFF_ERROR, FATA1_PIO0_OFF_SECCNT,
101       FATA1_PIO0_OFF_SECTOR, FATA1_PIO0_OFF_CYL_LO, FATA1_PIO0_OFF_CYL_HI,
102       FATA1_PIO0_OFF_SDH, FATA1_PIO0_OFF_COMMAND };
103 static const unsigned int	wdr_offsets_pion[] =
104     { FATA1_PION_OFF_DATA, FATA1_PION_OFF_ERROR, FATA1_PION_OFF_SECCNT,
105       FATA1_PION_OFF_SECTOR, FATA1_PION_OFF_CYL_LO, FATA1_PION_OFF_CYL_HI,
106       FATA1_PION_OFF_SDH, FATA1_PION_OFF_COMMAND };
107 
108 int
109 efa_probe(device_t parent, cfdata_t cfp, void *aux)
110 {
111 	/*
112 	 * FastATA 1200 uses portions of Gayle IDE interface, and efa driver
113 	 * can't coexist with wdc_amiga. Match "wdc" on an A1200, because
114 	 * FastATA 1200 does not autoconfigure.
115 	 */
116 	if (!matchname(aux, "wdc") || !is_a1200())
117 		return(0);
118 
119 	if (!efa_compare_status())
120 		return(0);
121 
122 #ifdef EFA_DEBUG
123 	aprint_normal("efa_probe succeeded\n");
124 #endif /* EFA_DEBUG */
125 
126 	return 100;
127 }
128 
129 void
130 efa_attach(device_t parent, device_t self, void *aux)
131 {
132 	int i;
133 	struct efa_softc *sc = device_private(self);
134 
135 	aprint_normal(": ELBOX FastATA 1200\n");
136 
137 	gayle_init();
138 
139 	efa_set_opts(sc);
140 
141 	if (!efa_mapbase(sc)) {
142 		aprint_error_dev(self, "couldn't map base addresses\n");
143 		return;
144 	}
145 	if (!efa_mapreg_gayle(sc)) {
146 		aprint_error_dev(self, "couldn't map Gayle registers\n");
147 		return;
148 	}
149 	if (!efa_mapreg_native(sc)) {
150 		aprint_error_dev(self, "couldn't map FastATA regsters\n");
151 		return;
152 	}
153 
154 	sc->sc_wdcdev.sc_atac.atac_pio_cap = 5;
155 	sc->sc_wdcdev.sc_atac.atac_nchannels = FATA1_CHANNELS;
156 	sc->sc_wdcdev.sc_atac.atac_set_modes = efa_setup_channel;
157 	sc->sc_wdcdev.sc_atac.atac_dev = self;
158 	sc->sc_wdcdev.sc_atac.atac_channels = sc->sc_chanlist;
159 	sc->sc_wdcdev.sc_atac.atac_cap = ATAC_CAP_DATA16;
160 	sc->sc_wdcdev.wdc_maxdrives = 2;
161 
162 	if (sc->sc_32bit_io)
163 		sc->sc_wdcdev.sc_atac.atac_cap |= ATAC_CAP_DATA32;
164 
165 	/*
166 	 * The following should work for polling mode, but it does not.
167 	 * if (sc->sc_no_intr)
168 	 *	sc->sc_wdcdev.sc_atac.atac_cap |= ATAC_CAP_NOIRQ;
169 	 */
170 
171 	wdc_allocate_regs(&sc->sc_wdcdev);
172 
173 	for (i = 0; i < FATA1_CHANNELS; i++)
174 		efa_attach_channel(sc, i);
175 
176 	if (sc->sc_no_intr) {
177 		sc->sc_fata_softintr = softint_establish(SOFTINT_BIO,
178 		    (void (*)(void *))efa_intr_soft, sc);
179 		if (sc->sc_fata_softintr == NULL) {
180 			aprint_error_dev(self, "couldn't create soft intr\n");
181 			return;
182 		}
183 		if (kthread_create(PRI_NONE, 0, NULL, efa_poll_kthread, sc,
184 		    NULL, "efa")) {
185 			aprint_error_dev(self, "couldn't create kthread\n");
186 			return;
187 		}
188 	} else {
189 		sc->sc_isr.isr_intr = efa_intr;
190 		sc->sc_isr.isr_arg = sc;
191 		sc->sc_isr.isr_ipl = 2;
192 		add_isr (&sc->sc_isr);
193 		gayle_intr_enable_set(GAYLE_INT_IDE);
194 	}
195 
196 }
197 
198 static void
199 efa_attach_channel(struct efa_softc *sc, int chnum)
200 {
201 #ifdef EFA_DEBUG
202 	device_t self;
203 
204 	self = sc->sc_wdcdev.sc_atac.atac_dev;
205 #endif /* EFA_DEBUG */
206 
207 	sc->sc_chanlist[chnum] = &sc->sc_ports[chnum].chan;
208 
209 	sc->sc_ports[chnum].chan.ch_channel = chnum;
210 	sc->sc_ports[chnum].chan.ch_atac = &sc->sc_wdcdev.sc_atac;
211 
212 	if (!sc->sc_32bit_io)
213 		efa_select_regset(sc, chnum, 0); /* Start in PIO0. */
214 	else
215 		efa_select_regset(sc, chnum, 3);
216 
217 	wdc_init_shadow_regs(CHAN_TO_WDC_REGS(&sc->sc_ports[chnum].chan));
218 
219 	wdcattach(&sc->sc_ports[chnum].chan);
220 
221 #ifdef EFA_DEBUG
222 	aprint_normal_dev(self, "done init for channel %d\n", chnum);
223 #endif
224 
225 }
226 
227 /* TODO: convert to callout(9) */
228 static void
229 efa_poll_kthread(void *arg)
230 {
231 	struct efa_softc *sc = arg;
232 
233 	for (;;) {
234 		/* TODO: actually check if interrupt status register is set */
235 		softint_schedule(sc->sc_fata_softintr);
236 		/* TODO: convert to kpause */
237 		tsleep(arg, PWAIT, "efa_poll", hz);
238 	}
239 }
240 
241 static void
242 efa_set_opts(struct efa_softc *sc)
243 {
244 	device_t self;
245 
246 	self = sc->sc_wdcdev.sc_atac.atac_dev;
247 
248 #ifdef EFA_32BIT_IO
249 	sc->sc_32bit_io = true;
250 #else
251 	sc->sc_32bit_io = false;
252 #endif /* EFA_32BIT_IO */
253 
254 #ifdef EFA_NO_INTR
255 	sc->sc_no_intr = true;		/* XXX: not yet! */
256 #else
257 	sc->sc_no_intr = false;
258 #endif /* EFA_NO_INTR */
259 
260 	if (sc->sc_no_intr)
261 		aprint_verbose_dev(self, "hardware interrupt disabled\n");
262 
263 	if (sc->sc_32bit_io)
264 		aprint_verbose_dev(self, "32-bit I/O enabled\n");
265 }
266 
267 int
268 efa_intr_soft(void *arg)
269 {
270 	int ret = 0;
271 	struct efa_softc *sc = (struct efa_softc *)arg;
272 
273 	/* TODO: check which channel needs servicing */
274 	/*
275 	uint8_t fataintreq;
276 	fataintreq = bus_space_read_1(sc->sc_ports[0].wdr[piom].cmd_iot,
277 	sc->sc_ports[chnum].intst[piom], 0);
278 	*/
279 
280 	ret = wdcintr(&sc->sc_ports[0].chan);
281 	ret = wdcintr(&sc->sc_ports[1].chan);
282 
283 	return ret;
284 }
285 
286 int
287 efa_intr(void *arg)
288 {
289 	struct efa_softc *sc = (struct efa_softc *)arg;
290 	int r1, r2, ret;
291 	uint8_t intreq;
292 
293 	intreq = gayle_intr_status();
294 	ret = 0;
295 
296 	if (intreq & GAYLE_INT_IDE) {
297 		gayle_intr_ack(0x7C | (intreq & 0x03));
298 		/* How to check which channel caused interrupt?
299 		 * Interrupt status register is not very useful here. */
300 		r1 = wdcintr(&sc->sc_ports[0].chan);
301 		r2 = wdcintr(&sc->sc_ports[1].chan);
302 		ret = r1 | r2;
303 	}
304 
305 	return ret;
306 }
307 
308 static bool
309 efa_mapbase(struct efa_softc *sc)
310 {
311 	static struct bus_space_tag fata_cmd_iot;
312 	static struct bus_space_tag gayle_cmd_iot;
313 	int i, j;
314 #ifdef EFA_DEBUG
315 	device_t self;
316 
317 	self = sc->sc_wdcdev.sc_atac.atac_dev;
318 #endif /* EFA_DEBUG */
319 
320 	gayle_cmd_iot.base = (bus_addr_t) ztwomap(GAYLE_IDE_BASE + 2);
321 	gayle_cmd_iot.absm = &amiga_bus_stride_4swap;
322 	fata_cmd_iot.base = (bus_addr_t) ztwomap(FATA1_BASE);
323 	fata_cmd_iot.absm = &amiga_bus_stride_4swap;
324 
325 #ifdef EFA_DEBUG
326 	aprint_normal_dev(self, "Gayle %x -> %x, FastATA %x -> %x\n",
327 	    GAYLE_IDE_BASE, gayle_cmd_iot.base, FATA1_BASE, fata_cmd_iot.base);
328 #endif
329 
330 	if (!gayle_cmd_iot.base)
331 		return false;
332 	if (!fata_cmd_iot.base)
333 		return false;
334 
335 	sc->sc_gayle_wdc_regs.cmd_iot = &gayle_cmd_iot;
336 	sc->sc_gayle_wdc_regs.ctl_iot = &gayle_cmd_iot;
337 
338 	for (i = 0; i < FATA1_CHANNELS; i++) {
339 		for (j = 0; j < PIO_COUNT; j++) {
340 			sc->sc_ports[i].wdr[j].cmd_iot = &fata_cmd_iot;
341 			sc->sc_ports[i].wdr[j].data32iot = &fata_cmd_iot;
342 			sc->sc_ports[i].wdr[j].ctl_iot = &gayle_cmd_iot;
343 		}
344 	}
345 
346 	return true;
347 }
348 
349 
350 /* Gayle IDE register mapping, we need it anyway. */
351 static bool
352 efa_mapreg_gayle(struct efa_softc *sc)
353 {
354 	int i;
355 
356 	struct wdc_regs *wdr = &sc->sc_gayle_wdc_regs;
357 
358 	if (bus_space_map(wdr->cmd_iot, 0, 0x40, 0,
359 	    &wdr->cmd_baseioh)) {
360 		return false;
361 	}
362 
363 	for (i = 0; i < WDC_NREG; i++) {
364 		if (bus_space_subregion(wdr->cmd_iot,
365 		    wdr->cmd_baseioh, i, i == 0 ? 4 : 1,
366 		    &wdr->cmd_iohs[i]) != 0) {
367 
368 			bus_space_unmap(wdr->cmd_iot,
369 			    wdr->cmd_baseioh, 0x40);
370 			return false;
371 		}
372 	}
373 
374 	if (bus_space_subregion(wdr->cmd_iot,
375 	    wdr->cmd_baseioh, 0x406, 1, &wdr->ctl_ioh))
376 		return false;
377 
378 	return true;
379 }
380 
381 /* Native FastATA register mapping, suitable for PIO modes 0 to 5. */
382 static bool
383 efa_mapreg_native(struct efa_softc *sc)
384 {
385 	struct wdc_regs *wdr_gayle = &sc->sc_gayle_wdc_regs;
386 	struct wdc_regs *wdr_fata;
387 	int i,j;
388 #ifdef EFA_DEBUG
389 	device_t self;
390 
391 	self = sc->sc_wdcdev.sc_atac.atac_dev;
392 #endif /* EFA_DEBUG */
393 
394 	for (i = 0; i < FATA1_CHANNELS; i++) {
395 
396 		for (j = 0; j < PIO_COUNT; j++) {
397 
398 			wdr_fata = &sc->sc_ports[i].wdr[j];
399 			sc->sc_ports[i].mode_ok[j] = false;
400 
401 			if (pio_offsets[j] == PIO_NSUPP) {
402 #ifdef EFA_DEBUG
403 				aprint_normal_dev(self,
404 				    "Skipping mapping for PIO mode %x\n", j);
405 #endif
406 				continue;
407 			}
408 
409 			if (bus_space_map(wdr_fata->cmd_iot,
410 			    pio_offsets[j] + FATA1_CHAN_SIZE * i,
411 			    FATA1_CHAN_SIZE, 0, &wdr_fata->cmd_baseioh)) {
412 			    return false;
413 			}
414 #ifdef EFA_DEBUG
415 			aprint_normal_dev(self,
416 			    "Chan %x PIO mode %x mapped %x -> %x\n",
417 			    i, j, (bus_addr_t) kvtop((void*)
418 			    wdr_fata->cmd_baseioh), (unsigned int)
419 			    wdr_fata->cmd_baseioh);
420 #endif
421 
422 			sc->sc_ports[i].mode_ok[j] = true;
423 
424 			if (j == 0)
425 				efa_fata_subregion_pio0(wdr_fata);
426 			else {
427 				if (sc->sc_32bit_io)
428 					efa_fata_subregion_pion(wdr_fata,
429 					    true);
430 				else
431 					efa_fata_subregion_pion(wdr_fata,
432 					    false);
433 
434 				bus_space_subregion(wdr_fata->cmd_iot,
435 				    wdr_fata->cmd_baseioh, FATA1_PION_OFF_INTST,
436 				    1, &sc->sc_ports[i].intst[j]);
437 			}
438 
439 			/* No 32-bit register for PIO0 ... */
440 			if (j == 0 && sc->sc_32bit_io)
441 				sc->sc_ports[i].mode_ok[j] = false;
442 
443 			wdr_fata->ctl_ioh = wdr_gayle->ctl_ioh;
444 		};
445 	}
446 	return true;
447 }
448 
449 
450 static void
451 efa_fata_subregion_pio0(struct wdc_regs *wdr_fata)
452 {
453 	int i;
454 
455 	for (i = 0; i < WDC_NREG; i++)
456 		bus_space_subregion(wdr_fata->cmd_iot,
457 		    wdr_fata->cmd_baseioh, wdr_offsets_pio0[i],
458 		    i == 0 ? 4 : 1, &wdr_fata->cmd_iohs[i]);
459 }
460 
461 static void
462 efa_fata_subregion_pion(struct wdc_regs *wdr_fata, bool data32)
463 {
464 	int i;
465 
466 	if (data32)
467 		bus_space_subregion(wdr_fata->cmd_iot, wdr_fata->cmd_baseioh,
468 		    FATA1_PION_OFF_DATA32, 8, &wdr_fata->data32ioh);
469 
470 	for (i = 0; i < WDC_NREG; i++)
471 		bus_space_subregion(wdr_fata->cmd_iot,
472 		    wdr_fata->cmd_baseioh, wdr_offsets_pion[i],
473 		    i == 0 ? 4 : 1, &wdr_fata->cmd_iohs[i]);
474 }
475 
476 static void
477 efa_setup_channel(struct ata_channel *chp)
478 {
479 	int drive, chnum;
480 	uint8_t mode;
481 	struct atac_softc *atac;
482 	struct ata_drive_datas *drvp;
483 	struct efa_softc *sc;
484 	int ipl;
485 #ifdef EFA_DEBUG
486 	device_t self;
487 #endif /* EFA_DEBUG */
488 
489 	chnum = chp->ch_channel;
490 	atac = chp->ch_atac;
491 
492 	sc = device_private(atac->atac_dev);
493 
494 	mode = 5; /* start with fastest possible setting */
495 
496 #ifdef EFA_DEBUG
497 	self = sc->sc_wdcdev.sc_atac.atac_dev;
498 	aprint_normal_dev(self, "efa_setup_channel for ch %d\n",
499 	    chnum);
500 #endif /* EFA_DEBUG */
501 
502 	/* We might be in the middle of something... so raise IPL. */
503 	ipl = splvm();
504 
505 	for (drive = 0; drive < 2; drive++) {
506 		drvp = &chp->ch_drive[drive];
507 
508 		if (drvp->drive_type == ATA_DRIVET_NONE)
509 			continue; /* nothing to see here */
510 
511 		if (drvp->PIO_cap < mode)
512 			mode = drvp->PIO_cap;
513 
514 		/* TODO: check if sc_ports->mode_ok */
515 
516 #ifdef EFA_DEBUG
517 		aprint_normal_dev(self, "drive %d supports %d\n",
518 		    drive, drvp->PIO_cap);
519 #endif /* EFA_DEBUG */
520 
521 		drvp->PIO_mode = mode;
522 	}
523 
524 	/* Change FastATA register set. */
525 	efa_select_regset(sc, chnum, mode);
526 	/* re-init shadow regs */
527 	wdc_init_shadow_regs(CHAN_TO_WDC_REGS(&sc->sc_ports[chnum].chan));
528 
529 	splx(ipl);
530 }
531 
532 static void
533 efa_select_regset(struct efa_softc *sc, int chnum, uint8_t piomode)
534 {
535 	struct wdc_softc *wdc;
536 #ifdef EFA_DEBUG
537 	device_t self;
538 
539 	self = sc->sc_wdcdev.sc_atac.atac_dev;
540 #endif /* EFA_DEBUG */
541 
542 	wdc = CHAN_TO_WDC(&sc->sc_ports[chnum].chan);
543 	wdc->regs[chnum] = sc->sc_ports[chnum].wdr[piomode];
544 
545 #ifdef EFA_DEBUG
546 	aprint_normal_dev(self, "switched ch %d to PIO %d\n",
547 	    chnum, piomode);
548 
549 	efa_debug_print_regmapping(&wdc->regs[chnum]);
550 #endif /* EFA_DEBUG */
551 }
552 
553 #ifdef EFA_DEBUG
554 static void
555 efa_debug_print_regmapping(struct wdc_regs *wdr_fata)
556 {
557 	int i;
558 	aprint_normal("base %x->%x",
559 	    (bus_addr_t) kvtop((void*) wdr_fata->cmd_baseioh),
560 	    (bus_addr_t) wdr_fata->cmd_baseioh);
561 	for (i = 0; i < WDC_NREG; i++) {
562 		aprint_normal("reg %x, %x->%x, ", i,
563 		    (bus_addr_t) kvtop((void*) wdr_fata->cmd_iohs[i]),
564 		    (bus_addr_t) wdr_fata->cmd_iohs[i]);
565 	}
566 	aprint_normal("\n");
567 }
568 #endif /* EFA_DEBUG */
569 
570 /* Compare the values of (status) command register in PIO0, PIO3 sets. */
571 static bool
572 efa_compare_status(void)
573 {
574 	uint8_t cmd0, cmd3;
575 	struct bus_space_tag fata_bst;
576 	bus_space_tag_t fata_iot;
577 	bus_space_handle_t cmd0_ioh, cmd3_ioh;
578 	bool rv;
579 
580 	rv = false;
581 
582 	fata_bst.base = (bus_addr_t) ztwomap(FATA1_BASE);
583 	fata_bst.absm = &amiga_bus_stride_4swap;
584 
585 	fata_iot = &fata_bst;
586 
587 	if (bus_space_map(fata_iot, pio_offsets[0], FATA1_CHAN_SIZE, 0,
588 	    &cmd0_ioh))
589 		return false;
590 	if (bus_space_map(fata_iot, pio_offsets[3], FATA1_CHAN_SIZE, 0,
591 	    &cmd3_ioh))
592 		return false;
593 
594 #ifdef EFA_DEBUG
595 	aprint_normal("probing for FastATA at %x, %x: ", (bus_addr_t) cmd0_ioh,
596 	    (bus_addr_t) cmd3_ioh);
597 #endif /* EFA_DEBUG */
598 
599 	cmd0 = bus_space_read_1(fata_iot, cmd0_ioh, FATA1_PIO0_OFF_COMMAND);
600 	cmd3 = bus_space_read_1(fata_iot, cmd3_ioh, FATA1_PION_OFF_COMMAND);
601 
602 	if (cmd0 == cmd3)
603 		rv = true;
604 
605 	if ( (cmd0 == 0xFF) || (cmd0 == 0x00) ) {
606 		/* Assume there's nothing there... */
607 		rv = false;
608 	}
609 
610 #ifdef EFA_DEBUG
611 	aprint_normal("cmd0 %x, cmd3 %x\n", cmd0, cmd3);
612 #endif /* EFA_DEBUG */
613 
614 	bus_space_unmap(fata_iot, pio_offsets[0], FATA1_CHAN_SIZE);
615 	bus_space_unmap(fata_iot, pio_offsets[3], FATA1_CHAN_SIZE);
616 
617 	return rv;
618 }
619 
620