xref: /netbsd-src/sys/dev/nand/nandemulator.c (revision f3cfa6f6ce31685c6c4a758bc430e69eb99f50a4)
1 /*	$NetBSD: nandemulator.c,v 1.8 2019/02/05 08:02:19 mrg Exp $	*/
2 
3 /*-
4  * Copyright (c) 2011 Department of Software Engineering,
5  *		      University of Szeged, Hungary
6  * Copyright (c) 2011 Adam Hoka <ahoka@NetBSD.org>
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by the Department of Software Engineering, University of Szeged, Hungary
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
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,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
27  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: nandemulator.c,v 1.8 2019/02/05 08:02:19 mrg Exp $");
36 
37 /* XXX this code likely needs work */
38 
39 #include <sys/param.h>
40 #include <sys/device.h>
41 #include <sys/conf.h>
42 #include <sys/kmem.h>
43 #include <sys/kernel.h>
44 
45 #include "nandemulator.h"
46 
47 #include <dev/nand/nand.h>
48 #include <dev/nand/onfi.h>
49 #include <dev/nand/nand_crc.h>
50 
51 #include "ioconf.h"
52 
53 extern struct cfdriver nandemulator_cd;
54 
55 static int nandemulator_match(device_t, cfdata_t, void *);
56 static void nandemulator_attach(device_t, device_t, void *);
57 static int nandemulator_detach(device_t, int);
58 
59 static void nandemulator_device_reset(device_t);
60 static void nandemulator_command(device_t, uint8_t);
61 static void nandemulator_address(device_t, uint8_t);
62 static void nandemulator_busy(device_t);
63 static void nandemulator_read_1(device_t, uint8_t *);
64 static void nandemulator_write_1(device_t, uint8_t);
65 static void nandemulator_read_2(device_t, uint16_t *);
66 static void nandemulator_write_2(device_t, uint16_t);
67 static void nandemulator_read_buf_1(device_t, void *, size_t);
68 static void nandemulator_read_buf_2(device_t, void *, size_t);
69 static void nandemulator_write_buf_1(device_t, const void *, size_t);
70 static void nandemulator_write_buf_2(device_t, const void *, size_t);
71 
72 static size_t nandemulator_address_to_page(device_t);
73 static size_t nandemulator_page_to_backend_offset(device_t, size_t);
74 static size_t nandemulator_column_address_to_subpage(device_t);
75 /*
76 #define NANDEMULATOR_DEBUG 1
77 
78 #ifdef NANDEMULATOR_DEBUG
79 #warning debug enabled
80 #define DPRINTF(x)	if (nandemulatordebug) printf x
81 #define DPRINTFN(n,x)	if (nandemulatordebug>(n)) printf x
82 #else
83 #error no debug
84 #define DPRINTF(x)
85 #define DPRINTFN(n,x)
86 #endif
87 
88 #ifdef NANDEMULATOR_DEBUG
89 int	nandemulatordebug = NANDEMULATOR_DEBUG;
90 #endif
91 */
92 
93 extern int nanddebug;
94 
95 enum {
96 	NANDEMULATOR_8BIT,
97 	NANDEMULATOR_16BIT
98 };
99 
100 struct nandemulator_softc {
101 	device_t		sc_dev;
102 	device_t		sc_nanddev;
103 
104 	int			sc_buswidth;
105 
106 	struct nand_interface	sc_nand_if;
107 
108 	uint8_t			sc_command;
109 	size_t			sc_io_len;
110 	uint8_t			*sc_io_pointer;
111 	uint64_t		sc_address;
112 
113 	uint8_t			*sc_backend;
114 	size_t			sc_backend_size;
115 	size_t			sc_device_size;
116 	bool			sc_register_writable;
117 
118 	uint8_t			sc_status_register;
119 	uint8_t			sc_ids[2];
120 	uint8_t			sc_onfi[4];
121 
122 	size_t			sc_page_size;
123 	size_t			sc_block_size;
124 	size_t			sc_spare_size;
125 	size_t			sc_lun_size;
126 	uint8_t			sc_row_cycles;
127 	uint8_t			sc_column_cycles;
128 	uint64_t		sc_row_mask;
129 
130 	int			sc_address_counter;
131 
132 	struct onfi_parameter_page	*sc_parameter_page;
133 };
134 
135 CFATTACH_DECL_NEW(nandemulator, sizeof(struct nandemulator_softc),
136     nandemulator_match, nandemulator_attach, nandemulator_detach, NULL);
137 
138 void
139 nandemulatorattach(int n)
140 {
141 	int i, err;
142 	cfdata_t cf;
143 
144 	aprint_debug("nandemulator: requested %d units\n", n);
145 
146 	err = config_cfattach_attach(nandemulator_cd.cd_name,
147 	    &nandemulator_ca);
148 	if (err) {
149 		aprint_error("%s: couldn't register cfattach: %d\n",
150 		    nandemulator_cd.cd_name, err);
151 		config_cfdriver_detach(&nandemulator_cd);
152 		return;
153 	}
154 	for (i = 0; i < n; i++) {
155 		cf = kmem_alloc(sizeof(struct cfdata), KM_NOSLEEP);
156 		if (cf == NULL) {
157 			aprint_error("%s: couldn't allocate cfdata\n",
158 			    nandemulator_cd.cd_name);
159 			continue;
160 		}
161 		cf->cf_name = nandemulator_cd.cd_name;
162 		cf->cf_atname = nandemulator_cd.cd_name;
163 		cf->cf_unit = i;
164 		cf->cf_fstate = FSTATE_STAR;
165 
166 		(void)config_attach_pseudo(cf);
167 	}
168 }
169 
170 /* ARGSUSED */
171 static int
172 nandemulator_match(device_t parent, cfdata_t match, void *aux)
173 {
174 	/* pseudo device, always attaches */
175 	return 1;
176 }
177 
178 static void
179 nandemulator_attach(device_t parent, device_t self, void *aux)
180 {
181 	struct nandemulator_softc *sc = device_private(self);
182 	int i;
183 
184 	aprint_normal_dev(self, "NAND emulator\n");
185 
186 	sc->sc_dev = self;
187 
188 	nand_init_interface(&sc->sc_nand_if);
189 
190 	sc->sc_nand_if.command = &nandemulator_command;
191 	sc->sc_nand_if.address = &nandemulator_address;
192 	sc->sc_nand_if.read_buf_1 = &nandemulator_read_buf_1;
193 	sc->sc_nand_if.read_buf_2 = &nandemulator_read_buf_2;
194 	sc->sc_nand_if.read_1 = &nandemulator_read_1;
195 	sc->sc_nand_if.read_2 = &nandemulator_read_2;
196 	sc->sc_nand_if.write_buf_1 = &nandemulator_write_buf_1;
197 	sc->sc_nand_if.write_buf_2 = &nandemulator_write_buf_2;
198 	sc->sc_nand_if.write_1 = &nandemulator_write_1;
199 	sc->sc_nand_if.write_2 = &nandemulator_write_2;
200 	sc->sc_nand_if.busy = &nandemulator_busy;
201 
202 	sc->sc_nand_if.ecc.necc_code_size = 3;
203 	sc->sc_nand_if.ecc.necc_block_size = 256;
204 
205 	if (!pmf_device_register1(sc->sc_dev, NULL, NULL, NULL))
206 		aprint_error_dev(sc->sc_dev,
207 		    "couldn't establish power handler\n");
208 
209 	sc->sc_buswidth = NANDEMULATOR_16BIT;	/* 16bit for now */
210 
211 	/* hardcode these now, make it configurable later */
212 	sc->sc_device_size = 32 * 1024 * 1024; /* 32MB */
213 	sc->sc_page_size = 2048;
214 	sc->sc_block_size = 64;
215 	sc->sc_lun_size =
216 	    sc->sc_device_size / (sc->sc_page_size * sc->sc_block_size);
217 	KASSERT(sc->sc_device_size %
218 	    (sc->sc_page_size * sc->sc_block_size) == 0);
219 	sc->sc_spare_size = 64;
220 
221 	sc->sc_column_cycles = 2;
222 	sc->sc_row_cycles = 3;
223 
224 	/* init the emulator data structures */
225 	sc->sc_backend_size =
226 	    sc->sc_device_size +
227 	    sc->sc_device_size / sc->sc_page_size * sc->sc_spare_size;
228 
229 	sc->sc_backend = kmem_alloc(sc->sc_backend_size, KM_SLEEP);
230 	memset(sc->sc_backend, 0xff, sc->sc_backend_size);
231 
232 	sc->sc_parameter_page =
233 	    kmem_zalloc(sizeof(struct onfi_parameter_page) * 4, KM_SLEEP);
234 
235 	struct onfi_parameter_page *opp;
236 	uint8_t sig[4] = { 'O', 'N', 'F', 'I' };
237 
238 	for (i = 0; i < 4; i++) {
239 		opp = &sc->sc_parameter_page[i];
240 
241 		opp->param_signature = htole32(*(uint32_t *)sig);
242 		opp->param_pagesize = htole32(sc->sc_page_size);
243 		opp->param_blocksize = htole32(sc->sc_block_size);
244 		opp->param_sparesize = htole16(sc->sc_spare_size);
245 		opp->param_lunsize = htole32(sc->sc_lun_size);
246 		opp->param_numluns = 1;
247 
248 		opp->param_manufacturer_id = 0x00;
249 		memcpy(opp->param_manufacturer,
250 		    "NETBSD", strlen("NETBSD"));
251 		memcpy(opp->param_model,
252 		    "NANDEMULATOR", strlen("NANDEMULATOR"));
253 
254 		uint16_t features = ONFI_FEATURE_16BIT;
255 		opp->param_features = htole16(features);
256 
257 		/* the lower 4 bits contain the row address cycles
258 		 * the upper 4 bits contain the column address cycles
259 		 */
260 		opp->param_addr_cycles = sc->sc_row_cycles;
261 		opp->param_addr_cycles |= (sc->sc_column_cycles << 4);
262 
263 		opp->param_integrity_crc = nand_crc16((uint8_t *)opp, 254);
264 	}
265 
266 	sc->sc_ids[0] = 0x00;
267 	sc->sc_ids[1] = 0x00;
268 
269 	sc->sc_onfi[0] = 'O';
270 	sc->sc_onfi[1] = 'N';
271 	sc->sc_onfi[2] = 'F';
272 	sc->sc_onfi[3] = 'I';
273 
274 	sc->sc_row_mask = 0x00;
275 	for (i = 0; i < sc->sc_row_cycles; i++) {
276 		sc->sc_row_mask <<= 8;
277 		sc->sc_row_mask |= 0xff;
278 	}
279 
280 	nandemulator_device_reset(self);
281 
282 	sc->sc_nanddev = nand_attach_mi(&sc->sc_nand_if, sc->sc_dev);
283 }
284 
285 static int
286 nandemulator_detach(device_t self, int flags)
287 {
288 	struct nandemulator_softc *sc = device_private(self);
289 	int ret = 0;
290 
291 	aprint_normal_dev(sc->sc_dev, "detaching emulator\n");
292 
293 	pmf_device_deregister(sc->sc_dev);
294 
295 	if (sc->sc_nanddev != NULL)
296 		ret = config_detach(sc->sc_nanddev, flags);
297 
298 	kmem_free(sc->sc_backend, sc->sc_backend_size);
299 	kmem_free(sc->sc_parameter_page,
300 	    sizeof(struct onfi_parameter_page) * 4);
301 
302 	return ret;
303 }
304 
305 /**
306  * bring the emulated device to a known state
307  */
308 static void
309 nandemulator_device_reset(device_t self)
310 {
311 	struct nandemulator_softc *sc = device_private(self);
312 
313 	DPRINTF(("device reset\n"));
314 
315 	sc->sc_command = 0;
316 	sc->sc_register_writable = false;
317 	sc->sc_io_len = 0;
318 	sc->sc_io_pointer = NULL;
319 	sc->sc_address = 0;
320 	sc->sc_address_counter = 0;
321 
322 	sc->sc_status_register = ONFI_STATUS_RDY | ONFI_STATUS_WP;
323 }
324 
325 static void
326 nandemulator_address_chip(device_t self)
327 {
328 	struct nandemulator_softc *sc = device_private(self);
329 	size_t page, offset;
330 
331 	KASSERT(sc->sc_address_counter ==
332 	    sc->sc_column_cycles + sc->sc_row_cycles);
333 
334 	if (sc->sc_address_counter !=
335 	    sc->sc_column_cycles + sc->sc_row_cycles) {
336 		aprint_error_dev(self, "incorrect number of address cycles\n");
337 		aprint_error_dev(self, "cc: %d, rc: %d, ac: %d\n",
338 		    sc->sc_column_cycles, sc->sc_row_cycles,
339 		    sc->sc_address_counter);
340 	}
341 
342 	page = nandemulator_address_to_page(self);
343 	offset = sc->sc_page_size * page;
344 
345 	DPRINTF(("READ/PROGRAM; page: 0x%jx (row addr: 0x%jx)\n",
346 		(uintmax_t )page,
347 		(uintmax_t )offset));
348 
349 	KASSERT(offset < sc->sc_device_size);
350 
351 	if (offset >= sc->sc_device_size) {
352 		aprint_error_dev(self, "address > device size!\n");
353 		sc->sc_io_len = 0;
354 	} else {
355 		size_t addr =
356 		    nandemulator_page_to_backend_offset(self, page);
357 		size_t pageoff =
358 		    nandemulator_column_address_to_subpage(self);
359 
360 		DPRINTF(("subpage: 0x%jx\n", (uintmax_t )pageoff));
361 
362 		KASSERT(pageoff <
363 		    sc->sc_page_size + sc->sc_spare_size);
364 		KASSERT(addr < sc->sc_backend_size);
365 
366 		sc->sc_io_pointer = sc->sc_backend + addr + pageoff;
367 		sc->sc_io_len =
368 		    sc->sc_page_size + sc->sc_spare_size - pageoff;
369 	}
370 }
371 
372 static void
373 nandemulator_command(device_t self, uint8_t command)
374 {
375 	struct nandemulator_softc *sc = device_private(self);
376 	size_t offset, page;
377 
378 	sc->sc_command = command;
379 	sc->sc_register_writable = false;
380 
381 	DPRINTF(("nandemulator command: 0x%hhx\n", command));
382 
383 	switch (command) {
384 	case ONFI_READ_STATUS:
385 		sc->sc_io_pointer = &sc->sc_status_register;
386 		sc->sc_io_len = 1;
387 		break;
388 	case ONFI_RESET:
389 		nandemulator_device_reset(self);
390 		break;
391 	case ONFI_PAGE_PROGRAM:
392 		sc->sc_register_writable = true;
393 		/* FALLTHROUGH */
394 	case ONFI_READ:
395 	case ONFI_BLOCK_ERASE:
396 		sc->sc_address_counter = 0;
397 		/* FALLTHROUGH */
398 	case ONFI_READ_ID:
399 	case ONFI_READ_PARAMETER_PAGE:
400 		sc->sc_io_len = 0;
401 		sc->sc_address = 0;
402 		break;
403 	case ONFI_PAGE_PROGRAM_START:
404 		/* XXX the program should only happen here */
405 		break;
406 	case ONFI_READ_START:
407 		nandemulator_address_chip(self);
408 		break;
409 	case ONFI_BLOCK_ERASE_START:
410 		page = nandemulator_address_to_page(self);
411 		offset = sc->sc_page_size * page;
412 
413 		KASSERT(offset %
414 		    (sc->sc_block_size * sc->sc_page_size) == 0);
415 
416 		KASSERT(offset < sc->sc_device_size);
417 
418 		if (offset >= sc->sc_device_size) {
419 			aprint_error_dev(self, "address > device size!\n");
420 		} else {
421 			size_t addr =
422 			    nandemulator_page_to_backend_offset(self, page);
423 
424 			size_t blocklen =
425 			    sc->sc_block_size *
426 			    (sc->sc_page_size + sc->sc_spare_size);
427 
428 			KASSERT(addr < sc->sc_backend_size);
429 			uint8_t *block = sc->sc_backend + addr;
430 
431 			DPRINTF(("erasing block at 0x%jx\n",
432 				(uintmax_t )offset));
433 
434 			memset(block, 0xff, blocklen);
435 		}
436 		sc->sc_io_len = 0;
437 		break;
438 	default:
439 		aprint_error_dev(self,
440 		    "invalid nand command (0x%hhx)\n", command);
441 		KASSERT(false);
442 		sc->sc_io_len = 0;
443 	}
444 };
445 
446 static void
447 nandemulator_address(device_t self, uint8_t address)
448 {
449 	struct nandemulator_softc *sc = device_private(self);
450 
451 	DPRINTF(("nandemulator_address: %hhx\n", address));
452 
453 	/**
454 	 * we have to handle read id/parameter page here,
455 	 * as we can read right after giving the address.
456 	 */
457 	switch (sc->sc_command) {
458 	case ONFI_READ_ID:
459 		if (address == 0x00) {
460 			sc->sc_io_len = 2;
461 			sc->sc_io_pointer = sc->sc_ids;
462 		} else if (address == 0x20) {
463 			sc->sc_io_len = 4;
464 			sc->sc_io_pointer = sc->sc_onfi;
465 		} else {
466 			sc->sc_io_len = 0;
467 		}
468 		break;
469 	case ONFI_READ_PARAMETER_PAGE:
470 		if (address == 0x00) {
471 			sc->sc_io_len = sizeof(struct onfi_parameter_page) * 4;
472 			sc->sc_io_pointer = (uint8_t *)sc->sc_parameter_page;
473 		} else {
474 			sc->sc_io_len = 0;
475 		}
476 		break;
477 	case ONFI_PAGE_PROGRAM:
478 		sc->sc_address <<= 8;
479 		sc->sc_address |= address;
480 		sc->sc_address_counter++;
481 
482 		if (sc->sc_address_counter ==
483 		    sc->sc_column_cycles + sc->sc_row_cycles) {
484 			nandemulator_address_chip(self);
485 		}
486 		break;
487 	default:
488 		sc->sc_address <<= 8;
489 		sc->sc_address |= address;
490 		sc->sc_address_counter++;
491 	}
492 };
493 
494 static void
495 nandemulator_busy(device_t self)
496 {
497 #ifdef NANDEMULATOR_DELAYS
498 	struct nandemulator_softc *sc = device_private(self);
499 
500 	/* do some delay depending on command */
501 	switch (sc->sc_command) {
502 	case ONFI_PAGE_PROGRAM_START:
503 	case ONFI_BLOCK_ERASE_START:
504 		DELAY(10);
505 		break;
506 	case ONFI_READ_START:
507 	default:
508 		DELAY(1);
509 	}
510 #endif
511 }
512 
513 static void
514 nandemulator_read_1(device_t self, uint8_t *data)
515 {
516 	struct nandemulator_softc *sc = device_private(self);
517 
518 	KASSERT(sc->sc_io_len > 0);
519 
520 	if (sc->sc_io_len > 0) {
521 		*data = *sc->sc_io_pointer;
522 
523 		sc->sc_io_pointer++;
524 		sc->sc_io_len--;
525 	} else {
526 		aprint_error_dev(self, "reading byte from invalid location\n");
527 		*data = 0xff;
528 	}
529 }
530 
531 static void
532 nandemulator_write_1(device_t self, uint8_t data)
533 {
534 	struct nandemulator_softc *sc = device_private(self);
535 
536 	KASSERT(sc->sc_register_writable);
537 
538 	if (!sc->sc_register_writable) {
539 		aprint_error_dev(self,
540 		    "trying to write read only location without effect\n");
541 		return;
542 	}
543 
544 	KASSERT(sc->sc_io_len > 0);
545 
546 	if (sc->sc_io_len > 0) {
547 		*sc->sc_io_pointer = data;
548 
549 		sc->sc_io_pointer++;
550 		sc->sc_io_len--;
551 	} else {
552 		aprint_error_dev(self, "write to invalid location\n");
553 	}
554 }
555 
556 static void
557 nandemulator_read_2(device_t self, uint16_t *data)
558 {
559 	struct nandemulator_softc *sc = device_private(self);
560 
561 	KASSERT(sc->sc_buswidth == NANDEMULATOR_16BIT);
562 
563 	if (sc->sc_buswidth != NANDEMULATOR_16BIT) {
564 		aprint_error_dev(self,
565 		    "trying to read a word on an 8bit chip\n");
566 		return;
567 	}
568 
569 	KASSERT(sc->sc_io_len > 1);
570 
571 	if (sc->sc_io_len > 1) {
572 		*data = *(uint16_t *)sc->sc_io_pointer;
573 
574 		sc->sc_io_pointer += 2;
575 		sc->sc_io_len -= 2;
576 	} else {
577 		aprint_error_dev(self, "reading word from invalid location\n");
578 		*data = 0xffff;
579 	}
580 }
581 
582 static void
583 nandemulator_write_2(device_t self, uint16_t data)
584 {
585 	struct nandemulator_softc *sc = device_private(self);
586 
587 	KASSERT(sc->sc_register_writable);
588 
589 	if (!sc->sc_register_writable) {
590 		aprint_error_dev(self,
591 		    "trying to write read only location without effect\n");
592 		return;
593 	}
594 
595 	KASSERT(sc->sc_buswidth == NANDEMULATOR_16BIT);
596 
597 	if (sc->sc_buswidth != NANDEMULATOR_16BIT) {
598 		aprint_error_dev(self,
599 		    "trying to write a word to an 8bit chip");
600 		return;
601 	}
602 
603 	KASSERT(sc->sc_io_len > 1);
604 
605 	if (sc->sc_io_len > 1) {
606 		*(uint16_t *)sc->sc_io_pointer = data;
607 
608 		sc->sc_io_pointer += 2;
609 		sc->sc_io_len -= 2;
610 	} else {
611 		aprint_error_dev(self, "writing to invalid location");
612 	}
613 }
614 
615 static void
616 nandemulator_read_buf_1(device_t self, void *buf, size_t len)
617 {
618 	uint8_t *addr;
619 
620 	KASSERT(buf != NULL);
621 	KASSERT(len >= 1);
622 
623 	addr = buf;
624 	while (len > 0) {
625 		nandemulator_read_1(self, addr);
626 		addr++, len--;
627 	}
628 }
629 
630 static void
631 nandemulator_read_buf_2(device_t self, void *buf, size_t len)
632 {
633 	uint16_t *addr;
634 
635 	KASSERT(buf != NULL);
636 	KASSERT(len >= 2);
637 	KASSERT(!(len & 0x01));
638 
639 	addr = buf;
640 	len /= 2;
641 	while (len > 0) {
642 		nandemulator_read_2(self, addr);
643 		addr++, len--;
644 	}
645 }
646 
647 static void
648 nandemulator_write_buf_1(device_t self, const void *buf, size_t len)
649 {
650 	const uint8_t *addr;
651 
652 	KASSERT(buf != NULL);
653 	KASSERT(len >= 1);
654 
655 	addr = buf;
656 	while (len > 0) {
657 		nandemulator_write_1(self, *addr);
658 		addr++, len--;
659 	}
660 }
661 
662 static void
663 nandemulator_write_buf_2(device_t self, const void *buf, size_t len)
664 {
665 	const uint16_t *addr;
666 
667 	KASSERT(buf != NULL);
668 	KASSERT(len >= 2);
669 	KASSERT(!(len & 0x01));
670 
671 	addr = buf;
672 	len /= 2;
673 	while (len > 0) {
674 		nandemulator_write_2(self, *addr);
675 		addr++, len--;
676 	}
677 }
678 
679 static size_t
680 nandemulator_address_to_page(device_t self)
681 {
682 	struct nandemulator_softc *sc = device_private(self);
683 	uint64_t address, offset;
684 	int i;
685 
686 	address = htole64(sc->sc_address);
687 	address &= sc->sc_row_mask;
688 
689 	offset = 0;
690 	for (i = 0; i < sc->sc_row_cycles; i++) {
691 		offset <<= 8;
692 		offset |= (address & 0xff);
693 		address >>= 8;
694 	}
695 
696 	return le64toh(offset);
697 }
698 
699 static size_t
700 nandemulator_column_address_to_subpage(device_t self)
701 {
702 	struct nandemulator_softc *sc = device_private(self);
703 	uint64_t address, offset;
704 	int i;
705 
706 	address = htole64(sc->sc_address);
707 	address >>= (8 * sc->sc_row_cycles);
708 
709 	offset = 0;
710 	for (i = 0; i < sc->sc_column_cycles; i++) {
711 		offset <<= 8;
712 		offset |= (address & 0xff);
713 		address >>= 8;
714 	}
715 
716 	if (sc->sc_buswidth == NANDEMULATOR_16BIT)
717 		return (size_t )le64toh(offset << 1);
718 	else
719 		return (size_t )le64toh(offset);
720 }
721 
722 static size_t
723 nandemulator_page_to_backend_offset(device_t self, size_t page)
724 {
725 	struct nandemulator_softc *sc = device_private(self);
726 
727 	return (sc->sc_page_size + sc->sc_spare_size) * page;
728 }
729 
730 #ifdef _MODULE
731 
732 MODULE(MODULE_CLASS_DRIVER, nandemulator, "nand");
733 
734 static const struct cfiattrdata nandbuscf_iattrdata = {
735 	"nandbus", 0, { { NULL, NULL, 0 }, }
736 };
737 static const struct cfiattrdata * const nandemulator_attrs[] = {
738 	&nandbuscf_iattrdata, NULL
739 };
740 
741 CFDRIVER_DECL(nandemulator, DV_DULL, nandemulator_attrs);
742 extern struct cfattach nandemulator_ca;
743 static int nandemulatorloc[] = { -1, -1 };
744 
745 static struct cfdata nandemulator_cfdata[] = {
746 	{
747 		.cf_name = "nandemulator",
748 		.cf_atname = "nandemulator",
749 		.cf_unit = 0,
750 		.cf_fstate = FSTATE_STAR,
751 		.cf_loc = nandemulatorloc,
752 		.cf_flags = 0,
753 		.cf_pspec = NULL,
754 	},
755 	{ NULL, NULL, 0, 0, NULL, 0, NULL }
756 };
757 
758 static int
759 nandemulator_modcmd(modcmd_t cmd, void *arg)
760 {
761 	int error;
762 
763 	switch (cmd) {
764 	case MODULE_CMD_INIT:
765 		error = config_cfdriver_attach(&nandemulator_cd);
766 		if (error) {
767 			return error;
768 		}
769 
770 		error = config_cfattach_attach(nandemulator_cd.cd_name,
771 		    &nandemulator_ca);
772 		if (error) {
773 			config_cfdriver_detach(&nandemulator_cd);
774 			aprint_error("%s: unable to register cfattach\n",
775 				nandemulator_cd.cd_name);
776 
777 			return error;
778 		}
779 
780 		error = config_cfdata_attach(nandemulator_cfdata, 1);
781 		if (error) {
782 			config_cfattach_detach(nandemulator_cd.cd_name,
783 			    &nandemulator_ca);
784 			config_cfdriver_detach(&nandemulator_cd);
785 			aprint_error("%s: unable to register cfdata\n",
786 				nandemulator_cd.cd_name);
787 
788 			return error;
789 		}
790 
791 		(void)config_attach_pseudo(nandemulator_cfdata);
792 
793 		return 0;
794 
795 	case MODULE_CMD_FINI:
796 		error = config_cfdata_detach(nandemulator_cfdata);
797 		if (error) {
798 			return error;
799 		}
800 
801 		config_cfattach_detach(nandemulator_cd.cd_name,
802 		    &nandemulator_ca);
803 		config_cfdriver_detach(&nandemulator_cd);
804 
805 		return 0;
806 
807 	case MODULE_CMD_AUTOUNLOAD:
808 		/* prevent auto-unload */
809 		return EBUSY;
810 
811 	default:
812 		return ENOTTY;
813 	}
814 }
815 
816 #endif
817