1/*	$NetBSD: omap2_nand.c,v 1.5 2021/08/07 16:18:46 thorpej Exp $	*/
2
3/*-
4 * Copyright (c) 2010 Department of Software Engineering,
5 *		      University of Szeged, Hungary
6 * Copyright (c) 2010 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/* Device driver for the NAND controller found in Texas Instruments OMAP2
35 * and later SOCs.
36 */
37
38#include <sys/cdefs.h>
39__KERNEL_RCSID(0, "$NetBSD: omap2_nand.c,v 1.5 2021/08/07 16:18:46 thorpej Exp $");
40
41/* TODO move to opt_* */
42#undef OMAP2_NAND_HARDWARE_ECC
43
44#include <sys/param.h>
45#include <sys/systm.h>
46#include <sys/cdefs.h>
47#include <sys/device.h>
48
49#include <sys/bus.h>
50
51#include <arm/ti/omap2_gpmcreg.h>
52
53#include <dev/nand/nand.h>
54#include <dev/nand/onfi.h>
55
56#include <dev/fdt/fdtvar.h>
57
58extern struct flash_interface nand_flash_if;
59extern int flash_print(void *, const char *);
60
61/* GPMC_STATUS */
62#define WAIT0		__BIT(8)	/* active low */
63
64/* GPMC_ECC_CONTROL */
65#define ECCCLEAR	__BIT(8)
66#define ECCPOINTER	__BITS(3,0)
67
68/* GPMC_ECC_CONFIG */
69#define ECCALGORITHM	__BIT(16)
70#define ECCCS		__BITS(3,1)
71#define ECC16B		__BIT(7)
72#define ECCENABLE	__BIT(0)
73/* GPMC_ECC_SIZE_CONFIG */
74#define ECCSIZE1	__BITS(29,22)
75
76/* GPMC_CONFIG1_i */
77#define DEVICETYPE	__BITS(11,10)
78#define DEVICESIZE	__BITS(13,12)
79
80#define MASKEDINT(mask, integer) ((integer) << (ffs(mask) - 1) & mask)
81
82/* NAND status register */
83#define NAND_WP_BIT __BIT(4)
84
85static int	omap2_nand_match(device_t, cfdata_t, void *);
86static void	omap2_nand_attach(device_t, device_t, void *);
87
88static void omap2_nand_command(device_t self, uint8_t command);
89static void omap2_nand_address(device_t self, uint8_t address);
90static void omap2_nand_busy(device_t self);
91static void omap2_nand_read_1(device_t self, uint8_t *data);
92static void omap2_nand_write_1(device_t self, uint8_t data);
93static void omap2_nand_read_2(device_t self, uint16_t *data);
94static void omap2_nand_write_2(device_t self, uint16_t data);
95bool omap2_nand_isbusy(device_t self);
96static void omap2_nand_read_buf_1(device_t self, void *buf, size_t len);
97static void omap2_nand_read_buf_2(device_t self, void *buf, size_t len);
98static void omap2_nand_write_buf_1(device_t self, const void *buf, size_t len);
99static void omap2_nand_write_buf_2(device_t self, const void *buf, size_t len);
100
101#ifdef OMAP2_NAND_HARDWARE_ECC
102static int omap2_nand_ecc_init(device_t self);
103static int omap2_nand_ecc_prepare(device_t self, int mode);
104static int omap2_nand_ecc_compute(device_t self, const uint8_t *data, uint8_t *ecc);
105static int omap2_nand_ecc_correct(device_t self, uint8_t *data, const uint8_t *oldecc,
106    const uint8_t *calcecc);
107#endif
108
109struct omap2_nand_softc {
110	device_t sc_dev;
111	device_t sc_nanddev;
112
113	int sc_cs;
114	int sc_buswidth;	/* 0: 8bit, 1: 16bit */
115
116	struct nand_interface	sc_nand_if;
117
118	bus_space_tag_t		sc_iot;
119	bus_space_handle_t	sc_ioh;
120	bus_space_handle_t	sc_gpmc_ioh;
121
122	bus_size_t		sc_cmd_reg;
123	bus_size_t		sc_addr_reg;
124	bus_size_t		sc_data_reg;
125};
126
127static const struct device_compatible_entry compat_data[] = {
128	{ .compat = "ti,omap2-nand" },
129	{ .compat = "ti,omap2-onenand" },
130	DEVICE_COMPAT_EOL
131};
132
133CFATTACH_DECL_NEW(omapnand, sizeof(struct omap2_nand_softc), omap2_nand_match,
134    omap2_nand_attach, NULL, NULL);
135
136static inline uint32_t
137gpmc_register_read(struct omap2_nand_softc *sc, bus_size_t reg)
138{
139	return bus_space_read_4(sc->sc_iot, sc->sc_gpmc_ioh, reg);
140}
141
142static inline void
143gpmc_register_write(struct omap2_nand_softc *sc, bus_size_t reg, const uint32_t data)
144{
145	bus_space_write_4(sc->sc_iot, sc->sc_gpmc_ioh, reg, data);
146}
147
148static void
149omap2_nand_command(device_t self, uint8_t command)
150{
151	struct omap2_nand_softc *sc = device_private(self);
152
153	bus_space_write_1(sc->sc_iot, sc->sc_ioh, sc->sc_cmd_reg, command);
154};
155
156static void
157omap2_nand_address(device_t self, uint8_t address)
158{
159	struct omap2_nand_softc *sc = device_private(self);
160
161	bus_space_write_1(sc->sc_iot, sc->sc_ioh, sc->sc_addr_reg, address);
162};
163
164bool
165omap2_nand_isbusy(device_t self)
166{
167	struct omap2_nand_softc *sc = device_private(self);
168	uint8_t status;
169
170	DELAY(1);		/* just to be sure we are not early */
171
172	bus_space_write_1(sc->sc_iot, sc->sc_ioh,
173	    sc->sc_cmd_reg, ONFI_READ_STATUS);
174
175	DELAY(1);
176
177	status = bus_space_read_1(sc->sc_iot,
178	    sc->sc_ioh, sc->sc_data_reg);
179
180	return !(status & ONFI_STATUS_RDY);
181};
182
183static int
184omap2_nand_match(device_t parent, cfdata_t match, void *aux)
185{
186	struct fdt_attach_args * const faa = aux;
187
188	return of_compatible_match(faa->faa_phandle, compat_data);
189}
190
191static void
192omap2_nand_attach(device_t parent, device_t self, void *aux)
193{
194	struct omap2_nand_softc *sc = device_private(self);
195	struct fdt_attach_args * const faa = aux;
196	const int phandle = faa->faa_phandle;
197	struct flash_attach_args flash;
198	bus_addr_t addr, part_addr;
199	bus_size_t size, part_size;
200	const u_int *prop;
201	uint32_t val;
202	int len, child;
203
204	if (fdtbus_get_reg(OF_parent(phandle), 0, &addr, &size) != 0) {
205		aprint_error(": couldn't get registers\n");
206		return;
207	}
208
209	sc->sc_iot = faa->faa_bst;
210	sc->sc_dev = self;
211
212	prop = fdtbus_get_prop(phandle, "reg", &len);
213	if (prop == NULL || len < 4) {
214		aprint_error(": couldn't read reg property\n");
215		return;
216	}
217
218	sc->sc_cs = be32toh(prop[0]);
219
220	/* map i/o space */
221	if (bus_space_map(sc->sc_iot, addr, size, 0, &sc->sc_gpmc_ioh) != 0) {
222		aprint_error(": couldn't map registers\n");
223		return;
224	}
225	if (bus_space_subregion(sc->sc_iot, sc->sc_gpmc_ioh, GPMC_CS_CONFIG(sc->sc_cs), 0x30, &sc->sc_ioh) != 0) {
226		aprint_error(": couldn't map cs registers\n");
227		return;
228	}
229
230	aprint_naive("\n");
231	aprint_normal(": CS%d\n", sc->sc_cs);
232
233        sc->sc_cmd_reg = GPMC_NAND_COMMAND_0 - GPMC_CONFIG1_0;
234	sc->sc_addr_reg = GPMC_NAND_ADDRESS_0 - GPMC_CONFIG1_0;
235	sc->sc_data_reg = GPMC_NAND_DATA_0 - GPMC_CONFIG1_0;
236
237	/* turn off write protection if enabled */
238	val = gpmc_register_read(sc, GPMC_CONFIG);
239	val |= NAND_WP_BIT;
240	gpmc_register_write(sc, GPMC_CONFIG, val);
241
242	/*
243	 * do the reset dance for NAND
244	 */
245	bus_space_write_1(sc->sc_iot, sc->sc_ioh,
246	    sc->sc_cmd_reg, ONFI_RESET);
247
248	omap2_nand_busy(self);
249
250	/* read GPMC_CONFIG1_i to get buswidth */
251	val = bus_space_read_4(sc->sc_iot, sc->sc_ioh, GPMC_CONFIG1_i);
252
253	if ((val & DEVICESIZE) == MASKEDINT(DEVICESIZE, 0x01)) {
254		/* 16bit */
255		sc->sc_buswidth = 1;
256	} else if ((val & DEVICESIZE) == MASKEDINT(DEVICESIZE, 0x00)) {
257		/* 8bit */
258		sc->sc_buswidth = 0;
259	} else {
260		panic("invalid buswidth reported by config1");
261	}
262
263	nand_init_interface(&sc->sc_nand_if);
264
265	sc->sc_nand_if.command = &omap2_nand_command;
266	sc->sc_nand_if.address = &omap2_nand_address;
267	sc->sc_nand_if.read_buf_1 = &omap2_nand_read_buf_1;
268	sc->sc_nand_if.read_buf_2 = &omap2_nand_read_buf_2;
269	sc->sc_nand_if.read_1 = &omap2_nand_read_1;
270	sc->sc_nand_if.read_2 = &omap2_nand_read_2;
271	sc->sc_nand_if.write_buf_1 = &omap2_nand_write_buf_1;
272	sc->sc_nand_if.write_buf_2 = &omap2_nand_write_buf_2;
273	sc->sc_nand_if.write_1 = &omap2_nand_write_1;
274	sc->sc_nand_if.write_2 = &omap2_nand_write_2;
275	sc->sc_nand_if.busy = &omap2_nand_busy;
276
277#ifdef OMAP2_NAND_HARDWARE_ECC
278	omap2_nand_ecc_init(self);
279	sc->sc_nand_if.ecc_compute = &omap2_nand_ecc_compute;
280	sc->sc_nand_if.ecc_correct = &omap2_nand_ecc_correct;
281	sc->sc_nand_if.ecc_prepare = &omap2_nand_ecc_prepare;
282	sc->sc_nand_if.ecc.necc_code_size = 3;
283	sc->sc_nand_if.ecc.necc_block_size = 512;
284	sc->sc_nand_if.ecc.necc_type = NAND_ECC_TYPE_HW;
285#else
286	sc->sc_nand_if.ecc.necc_code_size = 3;
287	sc->sc_nand_if.ecc.necc_block_size = 256;
288#endif	/* OMAP2_NAND_HARDWARE_ECC */
289
290	if (!pmf_device_register1(sc->sc_dev, NULL, NULL, NULL))
291		aprint_error_dev(sc->sc_dev,
292		    "couldn't establish power handler\n");
293
294	sc->sc_nanddev = nand_attach_mi(&sc->sc_nand_if, sc->sc_dev);
295	if (sc->sc_nanddev == NULL)
296		return;
297
298	for (child = OF_child(phandle); child; child = OF_peer(child)) {
299		if (!fdtbus_status_okay(child))
300			continue;
301
302		if (fdtbus_get_reg(child, 0, &part_addr, &part_size) != 0) {
303			aprint_error_dev(self, "couldn't parse partition %s\n",
304			    fdtbus_get_string(child, "name"));
305			continue;
306		}
307
308		memset(&flash, 0, sizeof(flash));
309		flash.flash_if = &nand_flash_if;
310		flash.partinfo.part_offset = part_addr;
311		flash.partinfo.part_size = part_size;
312		flash.partinfo.part_flags = 0;
313		flash.partinfo.part_name = fdtbus_get_string(child, "label");
314		if (flash.partinfo.part_name == NULL)
315			flash.partinfo.part_name = fdtbus_get_string(child, "name");
316
317		config_found(sc->sc_nanddev, &flash, flash_print, CFARGS_NONE);
318	}
319}
320
321static void
322omap2_nand_busy(device_t self)
323{
324	struct omap2_nand_softc *sc = device_private(self);
325
326	while (!(gpmc_register_read(sc, GPMC_STATUS) & WAIT0)) {
327		DELAY(1);
328	}
329}
330
331static void
332omap2_nand_read_1(device_t self, uint8_t *data)
333{
334	struct omap2_nand_softc *sc = device_private(self);
335
336	*data = bus_space_read_1(sc->sc_iot, sc->sc_ioh, sc->sc_data_reg);
337}
338
339static void
340omap2_nand_write_1(device_t self, uint8_t data)
341{
342	struct omap2_nand_softc *sc = device_private(self);
343
344	bus_space_write_1(sc->sc_iot, sc->sc_ioh, sc->sc_data_reg, data);
345}
346
347static void
348omap2_nand_read_2(device_t self, uint16_t *data)
349{
350	struct omap2_nand_softc *sc = device_private(self);
351
352	*data = bus_space_read_2(sc->sc_iot, sc->sc_ioh, sc->sc_data_reg);
353}
354
355static void
356omap2_nand_write_2(device_t self, uint16_t data)
357{
358	struct omap2_nand_softc *sc = device_private(self);
359
360	bus_space_write_2(sc->sc_iot, sc->sc_ioh, sc->sc_data_reg, data);
361}
362
363static void
364omap2_nand_read_buf_1(device_t self, void *buf, size_t len)
365{
366	struct omap2_nand_softc *sc = device_private(self);
367
368	KASSERT(buf != NULL);
369	KASSERT(len >= 1);
370
371	bus_space_read_multi_1(sc->sc_iot, sc->sc_ioh,
372	    sc->sc_data_reg, buf, len);
373}
374
375static void
376omap2_nand_read_buf_2(device_t self, void *buf, size_t len)
377{
378	struct omap2_nand_softc *sc = device_private(self);
379
380	KASSERT(buf != NULL);
381	KASSERT(len >= 2);
382	KASSERT(!(len & 0x01));
383
384	bus_space_read_multi_2(sc->sc_iot, sc->sc_ioh,
385	    sc->sc_data_reg, buf, len / 2);
386}
387
388static void
389omap2_nand_write_buf_1(device_t self, const void *buf, size_t len)
390{
391	struct omap2_nand_softc *sc = device_private(self);
392
393	KASSERT(buf != NULL);
394	KASSERT(len >= 1);
395
396	bus_space_write_multi_1(sc->sc_iot, sc->sc_ioh,
397	    sc->sc_data_reg, buf, len);
398}
399
400static void
401omap2_nand_write_buf_2(device_t self, const void *buf, size_t len)
402{
403	struct omap2_nand_softc *sc = device_private(self);
404
405	KASSERT(buf != NULL);
406	KASSERT(len >= 2);
407	KASSERT(!(len & 0x01));
408
409	bus_space_write_multi_2(sc->sc_iot, sc->sc_ioh,
410	    sc->sc_data_reg, buf, len / 2);
411}
412
413#ifdef OMAP2_NAND_HARDWARE_ECC
414static uint32_t
415convert_ecc(const uint8_t *ecc)
416{
417	return ecc[0] | (ecc[1] << 16) | ((ecc[2] & 0xf0) << 20) |
418	    ((ecc[2] & 0x0f) << 8);
419}
420
421static int
422omap2_nand_ecc_init(device_t self)
423{
424	struct omap2_nand_softc *sc = device_private(self);
425	uint32_t val;
426
427	val = gpmc_register_read(sc, GPMC_ECC_CONTROL);
428	/* clear ecc, select ecc register 1 */
429	val &= ~ECCPOINTER;
430	val |= ECCCLEAR | MASKEDINT(ECCPOINTER, 1);
431	gpmc_register_write(sc, GPMC_ECC_CONTROL, val);
432
433	/* XXX too many MAGIC */
434	/* set ecc size to 512, set all regs to eccsize1*/
435	val = gpmc_register_read(sc, GPMC_ECC_SIZE_CONFIG);
436	val &= ~ECCSIZE1;
437	val |= MASKEDINT(ECCSIZE1, 512) | 0x0f;
438	gpmc_register_write(sc, GPMC_ECC_CONTROL, val);
439
440	return 0;
441}
442
443static int
444omap2_nand_ecc_compute(device_t self, const uint8_t *data, uint8_t *ecc)
445{
446	struct omap2_nand_softc *sc = device_private(self);
447	uint32_t val;
448
449	/* read ecc result register */
450	val = gpmc_register_read(sc, GPMC_ECC1_RESULT);
451
452	ecc[0] = val & 0xff;
453	ecc[1] = (val >> 16) & 0xff;
454	ecc[2] = ((val >> 8) & 0x0f) | ((val >> 20) & 0xf0);
455
456	/* disable ecc engine */
457	val = gpmc_register_read(sc, GPMC_ECC_CONFIG);
458	val &= ~ECCENABLE;
459	gpmc_register_write(sc, GPMC_ECC_CONFIG, val);
460
461	return 0;
462}
463
464static int
465omap2_nand_ecc_prepare(device_t self, int mode)
466{
467	struct omap2_nand_softc *sc = device_private(self);
468	uint32_t val;
469
470	/* same for read/write */
471	switch (mode) {
472	case NAND_ECC_READ:
473	case NAND_ECC_WRITE:
474		val = gpmc_register_read(sc, GPMC_ECC_CONTROL);
475		/* clear ecc, select ecc register 1 */
476		val &= ~ECCPOINTER;
477		val |= ECCCLEAR | MASKEDINT(ECCPOINTER, 1);
478		gpmc_register_write(sc, GPMC_ECC_CONTROL, val);
479
480		val = gpmc_register_read(sc, GPMC_ECC_CONFIG);
481		val &= ~ECCCS;
482		val |= ECCENABLE | MASKEDINT(ECCCS, sc->sc_cs);
483		if (sc->sc_buswidth == 1)
484			val |= ECC16B;
485		else
486			val &= ~ECC16B;
487		gpmc_register_write(sc, GPMC_ECC_CONFIG, val);
488
489		break;
490	default:
491		aprint_error_dev(self, "invalid i/o mode for ecc prepare\n");
492		return -1;
493	}
494
495	return 0;
496}
497
498static int
499omap2_nand_ecc_correct(device_t self, uint8_t *data, const uint8_t *oldecc,
500    const uint8_t *calcecc)
501{
502	uint32_t oecc, cecc, xor;
503	uint16_t parity, offset;
504	uint8_t bit;
505
506	oecc = convert_ecc(oldecc);
507	cecc = convert_ecc(calcecc);
508
509	/* get the difference */
510	xor = oecc ^ cecc;
511
512	/* the data was correct if all bits are zero */
513	if (xor == 0x00)
514		return NAND_ECC_OK;
515
516	switch (popcount32(xor)) {
517	case 12:
518		/* single byte error */
519		parity = xor >> 16;
520		bit = (parity & 0x07);
521		offset = (parity >> 3) & 0x01ff;
522		/* correct bit */
523		data[offset] ^= (0x01 << bit);
524		return NAND_ECC_CORRECTED;
525	case 1:
526		return NAND_ECC_INVALID;
527	default:
528		/* erased page! */
529		if ((oecc == 0x0fff0fff) && (cecc == 0x00000000))
530			return NAND_ECC_OK;
531
532		return NAND_ECC_TWOBIT;
533	}
534}
535#endif /* !OMAP2_NAND_HARDWARE_ECC */
536