[mirror_ubuntu-jammy-kernel.git] / drivers / mtd / nand / nand_micron.c

/*
 * Copyright (C) 2017 Free Electrons
 * Copyright (C) 2017 NextThing Co
 *
 * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/mtd/rawnand.h>

/*
 * Special Micron status bit that indicates when the block has been
 * corrected by on-die ECC and should be rewritten
 */
#define NAND_STATUS_WRITE_RECOMMENDED	BIT(3)

struct nand_onfi_vendor_micron {
	u8 two_plane_read;
	u8 read_cache;
	u8 read_unique_id;
	u8 dq_imped;
	u8 dq_imped_num_settings;
	u8 dq_imped_feat_addr;
	u8 rb_pulldown_strength;
	u8 rb_pulldown_strength_feat_addr;
	u8 rb_pulldown_strength_num_settings;
	u8 otp_mode;
	u8 otp_page_start;
	u8 otp_data_prot_addr;
	u8 otp_num_pages;
	u8 otp_feat_addr;
	u8 read_retry_options;
	u8 reserved[72];
	u8 param_revision;
} __packed;

static int micron_nand_setup_read_retry(struct mtd_info *mtd, int retry_mode)
{
	struct nand_chip *chip = mtd_to_nand(mtd);
	u8 feature[ONFI_SUBFEATURE_PARAM_LEN] = {retry_mode};

	return chip->onfi_set_features(mtd, chip, ONFI_FEATURE_ADDR_READ_RETRY,
				       feature);
}

/*
 * Configure chip properties from Micron vendor-specific ONFI table
 */
static int micron_nand_onfi_init(struct nand_chip *chip)
{
	struct nand_onfi_params *p = &chip->onfi_params;
	struct nand_onfi_vendor_micron *micron = (void *)p->vendor;

	if (!chip->onfi_version)
		return 0;

	if (le16_to_cpu(p->vendor_revision) < 1)
		return 0;

	chip->read_retries = micron->read_retry_options;
	chip->setup_read_retry = micron_nand_setup_read_retry;

	return 0;
}

static int micron_nand_on_die_ooblayout_ecc(struct mtd_info *mtd, int section,
					    struct mtd_oob_region *oobregion)
{
	if (section >= 4)
		return -ERANGE;

	oobregion->offset = (section * 16) + 8;
	oobregion->length = 8;

	return 0;
}

static int micron_nand_on_die_ooblayout_free(struct mtd_info *mtd, int section,
					     struct mtd_oob_region *oobregion)
{
	if (section >= 4)
		return -ERANGE;

	oobregion->offset = (section * 16) + 2;
	oobregion->length = 6;

	return 0;
}

static const struct mtd_ooblayout_ops micron_nand_on_die_ooblayout_ops = {
	.ecc = micron_nand_on_die_ooblayout_ecc,
	.free = micron_nand_on_die_ooblayout_free,
};

static int micron_nand_on_die_ecc_setup(struct nand_chip *chip, bool enable)
{
	u8 feature[ONFI_SUBFEATURE_PARAM_LEN] = { 0, };

	if (enable)
		feature[0] |= ONFI_FEATURE_ON_DIE_ECC_EN;

	return chip->onfi_set_features(nand_to_mtd(chip), chip,
				       ONFI_FEATURE_ON_DIE_ECC, feature);
}

static int
micron_nand_read_page_on_die_ecc(struct mtd_info *mtd, struct nand_chip *chip,
				 uint8_t *buf, int oob_required,
				 int page)
{
	u8 status;
	int ret, max_bitflips = 0;

	ret = micron_nand_on_die_ecc_setup(chip, true);
	if (ret)
		return ret;

	ret = nand_read_page_op(chip, page, 0, NULL, 0);
	if (ret)
		goto out;

	ret = nand_status_op(chip, &status);
	if (ret)
		goto out;

	ret = nand_exit_status_op(chip);
	if (ret)
		goto out;

	if (status & NAND_STATUS_FAIL)
		mtd->ecc_stats.failed++;

	/*
	 * The internal ECC doesn't tell us the number of bitflips
	 * that have been corrected, but tells us if it recommends to
	 * rewrite the block. If it's the case, then we pretend we had
	 * a number of bitflips equal to the ECC strength, which will
	 * hint the NAND core to rewrite the block.
	 */
	else if (status & NAND_STATUS_WRITE_RECOMMENDED)
		max_bitflips = chip->ecc.strength;

	ret = nand_read_data_op(chip, buf, mtd->writesize, false);
	if (!ret && oob_required)
		ret = nand_read_data_op(chip, chip->oob_poi, mtd->oobsize,
					false);

out:
	micron_nand_on_die_ecc_setup(chip, false);

	return ret ? ret : max_bitflips;
}

static int
micron_nand_write_page_on_die_ecc(struct mtd_info *mtd, struct nand_chip *chip,
				  const uint8_t *buf, int oob_required,
				  int page)
{
	int ret;

	ret = micron_nand_on_die_ecc_setup(chip, true);
	if (ret)
		return ret;

	ret = nand_write_page_raw(mtd, chip, buf, oob_required, page);
	micron_nand_on_die_ecc_setup(chip, false);

	return ret;
}

enum {
	/* The NAND flash doesn't support on-die ECC */
	MICRON_ON_DIE_UNSUPPORTED,

	/*
	 * The NAND flash supports on-die ECC and it can be
	 * enabled/disabled by a set features command.
	 */
	MICRON_ON_DIE_SUPPORTED,

	/*
	 * The NAND flash supports on-die ECC, and it cannot be
	 * disabled.
	 */
	MICRON_ON_DIE_MANDATORY,
};

/*
 * Try to detect if the NAND support on-die ECC. To do this, we enable
 * the feature, and read back if it has been enabled as expected. We
 * also check if it can be disabled, because some Micron NANDs do not
 * allow disabling the on-die ECC and we don't support such NANDs for
 * now.
 *
 * This function also has the side effect of disabling on-die ECC if
 * it had been left enabled by the firmware/bootloader.
 */
static int micron_supports_on_die_ecc(struct nand_chip *chip)
{
	u8 feature[ONFI_SUBFEATURE_PARAM_LEN] = { 0, };
	int ret;

	if (chip->onfi_version == 0)
		return MICRON_ON_DIE_UNSUPPORTED;

	if (chip->bits_per_cell != 1)
		return MICRON_ON_DIE_UNSUPPORTED;

	ret = micron_nand_on_die_ecc_setup(chip, true);
	if (ret)
		return MICRON_ON_DIE_UNSUPPORTED;

	chip->onfi_get_features(nand_to_mtd(chip), chip,
				ONFI_FEATURE_ON_DIE_ECC, feature);
	if ((feature[0] & ONFI_FEATURE_ON_DIE_ECC_EN) == 0)
		return MICRON_ON_DIE_UNSUPPORTED;

	ret = micron_nand_on_die_ecc_setup(chip, false);
	if (ret)
		return MICRON_ON_DIE_UNSUPPORTED;

	chip->onfi_get_features(nand_to_mtd(chip), chip,
				ONFI_FEATURE_ON_DIE_ECC, feature);
	if (feature[0] & ONFI_FEATURE_ON_DIE_ECC_EN)
		return MICRON_ON_DIE_MANDATORY;

	/*
	 * Some Micron NANDs have an on-die ECC of 4/512, some other
	 * 8/512. We only support the former.
	 */
	if (chip->onfi_params.ecc_bits != 4)
		return MICRON_ON_DIE_UNSUPPORTED;

	return MICRON_ON_DIE_SUPPORTED;
}

static int micron_nand_init(struct nand_chip *chip)
{
	struct mtd_info *mtd = nand_to_mtd(chip);
	int ondie;
	int ret;

	ret = micron_nand_onfi_init(chip);
	if (ret)
		return ret;

	if (mtd->writesize == 2048)
		chip->bbt_options |= NAND_BBT_SCAN2NDPAGE;

	ondie = micron_supports_on_die_ecc(chip);

	if (ondie == MICRON_ON_DIE_MANDATORY) {
		pr_err("On-die ECC forcefully enabled, not supported\n");
		return -EINVAL;
	}

	if (chip->ecc.mode == NAND_ECC_ON_DIE) {
		if (ondie == MICRON_ON_DIE_UNSUPPORTED) {
			pr_err("On-die ECC selected but not supported\n");
			return -EINVAL;
		}

		chip->ecc.bytes = 8;
		chip->ecc.size = 512;
		chip->ecc.strength = 4;
		chip->ecc.algo = NAND_ECC_BCH;
		chip->ecc.read_page = micron_nand_read_page_on_die_ecc;
		chip->ecc.write_page = micron_nand_write_page_on_die_ecc;
		chip->ecc.read_page_raw = nand_read_page_raw;
		chip->ecc.write_page_raw = nand_write_page_raw;

		mtd_set_ooblayout(mtd, &micron_nand_on_die_ooblayout_ops);
	}

	return 0;
}

const struct nand_manufacturer_ops micron_nand_manuf_ops = {
	.init = micron_nand_init,
};
Commit	Line	Data
10d4e75c BB	1	/*
	2	* Copyright (C) 2017 Free Electrons
	3	* Copyright (C) 2017 NextThing Co
	4	*
	5	* Author: Boris Brezillon <boris.brezillon@free-electrons.com>
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*/
	17
d4092d76	18	#include <linux/mtd/rawnand.h>
10d4e75c	19
9748e1d8 TP	20	/*
	21	* Special Micron status bit that indicates when the block has been
	22	* corrected by on-die ECC and should be rewritten
	23	*/
	24	#define NAND_STATUS_WRITE_RECOMMENDED BIT(3)
	25
10d4e75c BB	26	struct nand_onfi_vendor_micron {
	27	u8 two_plane_read;
	28	u8 read_cache;
	29	u8 read_unique_id;
	30	u8 dq_imped;
	31	u8 dq_imped_num_settings;
	32	u8 dq_imped_feat_addr;
	33	u8 rb_pulldown_strength;
	34	u8 rb_pulldown_strength_feat_addr;
	35	u8 rb_pulldown_strength_num_settings;
	36	u8 otp_mode;
	37	u8 otp_page_start;
	38	u8 otp_data_prot_addr;
	39	u8 otp_num_pages;
	40	u8 otp_feat_addr;
	41	u8 read_retry_options;
	42	u8 reserved[72];
	43	u8 param_revision;
	44	} __packed;
	45
	46	static int micron_nand_setup_read_retry(struct mtd_info *mtd, int retry_mode)
	47	{
	48	struct nand_chip *chip = mtd_to_nand(mtd);
	49	u8 feature[ONFI_SUBFEATURE_PARAM_LEN] = {retry_mode};
	50
	51	return chip->onfi_set_features(mtd, chip, ONFI_FEATURE_ADDR_READ_RETRY,
	52	feature);
	53	}
	54
	55	/*
	56	* Configure chip properties from Micron vendor-specific ONFI table
	57	*/
	58	static int micron_nand_onfi_init(struct nand_chip *chip)
	59	{
	60	struct nand_onfi_params *p = &chip->onfi_params;
	61	struct nand_onfi_vendor_micron micron = (void )p->vendor;
	62
	63	if (!chip->onfi_version)
	64	return 0;
	65
	66	if (le16_to_cpu(p->vendor_revision) < 1)
	67	return 0;
	68
	69	chip->read_retries = micron->read_retry_options;
	70	chip->setup_read_retry = micron_nand_setup_read_retry;
	71
	72	return 0;
	73	}
	74
9748e1d8 TP	75	static int micron_nand_on_die_ooblayout_ecc(struct mtd_info *mtd, int section,
	76	struct mtd_oob_region *oobregion)
	77	{
	78	if (section >= 4)
	79	return -ERANGE;
	80
	81	oobregion->offset = (section * 16) + 8;
	82	oobregion->length = 8;
	83
	84	return 0;
	85	}
	86
	87	static int micron_nand_on_die_ooblayout_free(struct mtd_info *mtd, int section,
	88	struct mtd_oob_region *oobregion)
	89	{
	90	if (section >= 4)
	91	return -ERANGE;
	92
	93	oobregion->offset = (section * 16) + 2;
	94	oobregion->length = 6;
	95
	96	return 0;
	97	}
	98
	99	static const struct mtd_ooblayout_ops micron_nand_on_die_ooblayout_ops = {
	100	.ecc = micron_nand_on_die_ooblayout_ecc,
	101	.free = micron_nand_on_die_ooblayout_free,
	102	};
	103
	104	static int micron_nand_on_die_ecc_setup(struct nand_chip *chip, bool enable)
	105	{
	106	u8 feature[ONFI_SUBFEATURE_PARAM_LEN] = { 0, };
	107
	108	if (enable)
	109	feature[0] \|= ONFI_FEATURE_ON_DIE_ECC_EN;
	110
	111	return chip->onfi_set_features(nand_to_mtd(chip), chip,
	112	ONFI_FEATURE_ON_DIE_ECC, feature);
	113	}
	114
	115	static int
	116	micron_nand_read_page_on_die_ecc(struct mtd_info mtd, struct nand_chip chip,
	117	uint8_t *buf, int oob_required,
	118	int page)
	119	{
97d90da8 BB	120	u8 status;
97d90da8 BB	121	int ret, max_bitflips = 0;
9748e1d8	122
97d90da8 BB	123	ret = micron_nand_on_die_ecc_setup(chip, true);
	124	if (ret)
	125	return ret;
	126
	127	ret = nand_read_page_op(chip, page, 0, NULL, 0);
	128	if (ret)
	129	goto out;
	130
	131	ret = nand_status_op(chip, &status);
	132	if (ret)
	133	goto out;
	134
	135	ret = nand_exit_status_op(chip);
	136	if (ret)
	137	goto out;
9748e1d8	138
9748e1d8 TP	139	if (status & NAND_STATUS_FAIL)
9748e1d8 TP	140	mtd->ecc_stats.failed++;
97d90da8	141
9748e1d8 TP	142	/*
	143	* The internal ECC doesn't tell us the number of bitflips
	144	* that have been corrected, but tells us if it recommends to
	145	* rewrite the block. If it's the case, then we pretend we had
	146	* a number of bitflips equal to the ECC strength, which will
	147	* hint the NAND core to rewrite the block.
	148	*/
	149	else if (status & NAND_STATUS_WRITE_RECOMMENDED)
	150	max_bitflips = chip->ecc.strength;
	151
25f815f6 BB	152	ret = nand_read_data_op(chip, buf, mtd->writesize, false);
	153	if (!ret && oob_required)
	154	ret = nand_read_data_op(chip, chip->oob_poi, mtd->oobsize,
	155	false);
9748e1d8	156
97d90da8	157	out:
9748e1d8 TP	158	micron_nand_on_die_ecc_setup(chip, false);
9748e1d8 TP	159
97d90da8	160	return ret ? ret : max_bitflips;
9748e1d8 TP	161	}
	162
	163	static int
	164	micron_nand_write_page_on_die_ecc(struct mtd_info mtd, struct nand_chip chip,
	165	const uint8_t *buf, int oob_required,
	166	int page)
	167	{
97d90da8 BB	168	int ret;
	169
	170	ret = micron_nand_on_die_ecc_setup(chip, true);
	171	if (ret)
	172	return ret;
41145649	173
97d90da8	174	ret = nand_write_page_raw(mtd, chip, buf, oob_required, page);
9748e1d8 TP	175	micron_nand_on_die_ecc_setup(chip, false);
9748e1d8 TP	176
97d90da8	177	return ret;
9748e1d8 TP	178	}
9748e1d8 TP	179
9748e1d8 TP	180	enum {
	181	/* The NAND flash doesn't support on-die ECC */
	182	MICRON_ON_DIE_UNSUPPORTED,
	183
	184	/*
	185	* The NAND flash supports on-die ECC and it can be
	186	* enabled/disabled by a set features command.
	187	*/
	188	MICRON_ON_DIE_SUPPORTED,
	189
	190	/*
	191	* The NAND flash supports on-die ECC, and it cannot be
	192	* disabled.
	193	*/
	194	MICRON_ON_DIE_MANDATORY,
	195	};
	196
	197	/*
	198	* Try to detect if the NAND support on-die ECC. To do this, we enable
	199	* the feature, and read back if it has been enabled as expected. We
	200	* also check if it can be disabled, because some Micron NANDs do not
	201	* allow disabling the on-die ECC and we don't support such NANDs for
	202	* now.
	203	*
	204	* This function also has the side effect of disabling on-die ECC if
	205	* it had been left enabled by the firmware/bootloader.
	206	*/
	207	static int micron_supports_on_die_ecc(struct nand_chip *chip)
	208	{
	209	u8 feature[ONFI_SUBFEATURE_PARAM_LEN] = { 0, };
	210	int ret;
	211
	212	if (chip->onfi_version == 0)
	213	return MICRON_ON_DIE_UNSUPPORTED;
	214
	215	if (chip->bits_per_cell != 1)
	216	return MICRON_ON_DIE_UNSUPPORTED;
	217
	218	ret = micron_nand_on_die_ecc_setup(chip, true);
	219	if (ret)
	220	return MICRON_ON_DIE_UNSUPPORTED;
	221
	222	chip->onfi_get_features(nand_to_mtd(chip), chip,
	223	ONFI_FEATURE_ON_DIE_ECC, feature);
	224	if ((feature[0] & ONFI_FEATURE_ON_DIE_ECC_EN) == 0)
	225	return MICRON_ON_DIE_UNSUPPORTED;
	226
	227	ret = micron_nand_on_die_ecc_setup(chip, false);
	228	if (ret)
	229	return MICRON_ON_DIE_UNSUPPORTED;
	230
	231	chip->onfi_get_features(nand_to_mtd(chip), chip,
	232	ONFI_FEATURE_ON_DIE_ECC, feature);
	233	if (feature[0] & ONFI_FEATURE_ON_DIE_ECC_EN)
	234	return MICRON_ON_DIE_MANDATORY;
	235
	236	/*
	237	* Some Micron NANDs have an on-die ECC of 4/512, some other
	238	* 8/512. We only support the former.
	239	*/
	240	if (chip->onfi_params.ecc_bits != 4)
	241	return MICRON_ON_DIE_UNSUPPORTED;
	242
	243	return MICRON_ON_DIE_SUPPORTED;
244	}
245
10d4e75c BB	246	static int micron_nand_init(struct nand_chip *chip)
	247	{
	248	struct mtd_info *mtd = nand_to_mtd(chip);
9748e1d8	249	int ondie;
10d4e75c BB	250	int ret;
	251
	252	ret = micron_nand_onfi_init(chip);
	253	if (ret)
	254	return ret;
	255
	256	if (mtd->writesize == 2048)
	257	chip->bbt_options \|= NAND_BBT_SCAN2NDPAGE;
	258
9748e1d8 TP	259	ondie = micron_supports_on_die_ecc(chip);
	260
	261	if (ondie == MICRON_ON_DIE_MANDATORY) {
	262	pr_err("On-die ECC forcefully enabled, not supported\n");
	263	return -EINVAL;
	264	}
	265
	266	if (chip->ecc.mode == NAND_ECC_ON_DIE) {
	267	if (ondie == MICRON_ON_DIE_UNSUPPORTED) {
	268	pr_err("On-die ECC selected but not supported\n");
	269	return -EINVAL;
	270	}
	271
9748e1d8 TP	272	chip->ecc.bytes = 8;
	273	chip->ecc.size = 512;
	274	chip->ecc.strength = 4;
	275	chip->ecc.algo = NAND_ECC_BCH;
	276	chip->ecc.read_page = micron_nand_read_page_on_die_ecc;
	277	chip->ecc.write_page = micron_nand_write_page_on_die_ecc;
25f815f6 BB	278	chip->ecc.read_page_raw = nand_read_page_raw;
25f815f6 BB	279	chip->ecc.write_page_raw = nand_write_page_raw;
9748e1d8 TP	280
	281	mtd_set_ooblayout(mtd, &micron_nand_on_die_ooblayout_ops);
	282	}
	283
10d4e75c BB	284	return 0;
	285	}
	286
	287	const struct nand_manufacturer_ops micron_nand_manuf_ops = {
	288	.init = micron_nand_init,
	289	};