drivers/mtd/nand/raw/nand_macronix.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2017 Free Electrons
 * Copyright (C) 2017 NextThing Co
 *
 * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
 */

#include "internals.h"

#define MACRONIX_READ_RETRY_BIT BIT(0)
#define MACRONIX_NUM_READ_RETRY_MODES 6

#define ONFI_FEATURE_ADDR_MXIC_RANDOMIZER 0xB0
#define MACRONIX_RANDOMIZER_BIT BIT(1)
#define MACRONIX_RANDOMIZER_ENPGM BIT(0)
#define MACRONIX_RANDOMIZER_RANDEN BIT(1)
#define MACRONIX_RANDOMIZER_RANDOPT BIT(2)
#define MACRONIX_RANDOMIZER_MODE_ENTER	\
	(MACRONIX_RANDOMIZER_ENPGM |	\
	 MACRONIX_RANDOMIZER_RANDEN |	\
	 MACRONIX_RANDOMIZER_RANDOPT)
#define MACRONIX_RANDOMIZER_MODE_EXIT	\
	(MACRONIX_RANDOMIZER_RANDEN |	\
	 MACRONIX_RANDOMIZER_RANDOPT)

struct nand_onfi_vendor_macronix {
	u8 reserved;
	u8 reliability_func;
} __packed;

static int macronix_nand_setup_read_retry(struct nand_chip *chip, int mode)
{
	u8 feature[ONFI_SUBFEATURE_PARAM_LEN];

	if (!chip->parameters.supports_set_get_features ||
	    !test_bit(ONFI_FEATURE_ADDR_READ_RETRY,
		      chip->parameters.set_feature_list))
		return -ENOTSUPP;

	feature[0] = mode;
	return nand_set_features(chip, ONFI_FEATURE_ADDR_READ_RETRY, feature);
}

static int macronix_nand_randomizer_check_enable(struct nand_chip *chip)
{
	u8 feature[ONFI_SUBFEATURE_PARAM_LEN];
	int ret;

	ret = nand_get_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
				feature);
	if (ret < 0)
		return ret;

	if (feature[0])
		return feature[0];

	feature[0] = MACRONIX_RANDOMIZER_MODE_ENTER;
	ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
				feature);
	if (ret < 0)
		return ret;

	/* RANDEN and RANDOPT OTP bits are programmed */
	feature[0] = 0x0;
	ret = nand_prog_page_op(chip, 0, 0, feature, 1);
	if (ret < 0)
		return ret;

	ret = nand_get_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
				feature);
	if (ret < 0)
		return ret;

	feature[0] &= MACRONIX_RANDOMIZER_MODE_EXIT;
	ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
				feature);
	if (ret < 0)
		return ret;

	return 0;
}

static void macronix_nand_onfi_init(struct nand_chip *chip)
{
	struct nand_parameters *p = &chip->parameters;
	struct nand_onfi_vendor_macronix *mxic;
	struct device_node *dn = nand_get_flash_node(chip);
	int rand_otp = 0;
	int ret;

	if (!p->onfi)
		return;

	if (of_find_property(dn, "mxic,enable-randomizer-otp", NULL))
		rand_otp = 1;

	mxic = (struct nand_onfi_vendor_macronix *)p->onfi->vendor;
	/* Subpage write is prohibited in randomizer operatoin */
	if (rand_otp && chip->options & NAND_NO_SUBPAGE_WRITE &&
	    mxic->reliability_func & MACRONIX_RANDOMIZER_BIT) {
		if (p->supports_set_get_features) {
			bitmap_set(p->set_feature_list,
				   ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
			bitmap_set(p->get_feature_list,
				   ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
			ret = macronix_nand_randomizer_check_enable(chip);
			if (ret < 0) {
				bitmap_clear(p->set_feature_list,
					     ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
					     1);
				bitmap_clear(p->get_feature_list,
					     ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
					     1);
				pr_info("Macronix NAND randomizer failed\n");
			} else {
				pr_info("Macronix NAND randomizer enabled\n");
			}
		}
	}

	if ((mxic->reliability_func & MACRONIX_READ_RETRY_BIT) == 0)
		return;

	chip->read_retries = MACRONIX_NUM_READ_RETRY_MODES;
	chip->setup_read_retry = macronix_nand_setup_read_retry;

	if (p->supports_set_get_features) {
		bitmap_set(p->set_feature_list,
			   ONFI_FEATURE_ADDR_READ_RETRY, 1);
		bitmap_set(p->get_feature_list,
			   ONFI_FEATURE_ADDR_READ_RETRY, 1);
	}
}

/*
 * Macronix AC series does not support using SET/GET_FEATURES to change
 * the timings unlike what is declared in the parameter page. Unflag
 * this feature to avoid unnecessary downturns.
 */
static void macronix_nand_fix_broken_get_timings(struct nand_chip *chip)
{
	int i;
	static const char * const broken_get_timings[] = {
		"MX30LF1G18AC",
		"MX30LF1G28AC",
		"MX30LF2G18AC",
		"MX30LF2G28AC",
		"MX30LF4G18AC",
		"MX30LF4G28AC",
		"MX60LF8G18AC",
		"MX30UF1G18AC",
		"MX30UF1G16AC",
		"MX30UF2G18AC",
		"MX30UF2G16AC",
		"MX30UF4G18AC",
		"MX30UF4G16AC",
		"MX30UF4G28AC",
	};

	if (!chip->parameters.supports_set_get_features)
		return;

	i = match_string(broken_get_timings, ARRAY_SIZE(broken_get_timings),
			 chip->parameters.model);
	if (i < 0)
		return;

	bitmap_clear(chip->parameters.get_feature_list,
		     ONFI_FEATURE_ADDR_TIMING_MODE, 1);
	bitmap_clear(chip->parameters.set_feature_list,
		     ONFI_FEATURE_ADDR_TIMING_MODE, 1);
}

static int macronix_nand_init(struct nand_chip *chip)
{
	if (nand_is_slc(chip))
		chip->options |= NAND_BBM_FIRSTPAGE | NAND_BBM_SECONDPAGE;

	macronix_nand_fix_broken_get_timings(chip);
	macronix_nand_onfi_init(chip);

	return 0;
}

const struct nand_manufacturer_ops macronix_nand_manuf_ops = {
	.init = macronix_nand_init,
};