xref: /openbmc/linux/drivers/mtd/nand/raw/nand_jedec.c (revision 82df5b73)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
4  *		  2002-2006 Thomas Gleixner (tglx@linutronix.de)
5  *
6  *  Credits:
7  *	David Woodhouse for adding multichip support
8  *
9  *	Aleph One Ltd. and Toby Churchill Ltd. for supporting the
10  *	rework for 2K page size chips
11  *
12  * This file contains all ONFI helpers.
13  */
14 
15 #include <linux/slab.h>
16 
17 #include "internals.h"
18 
19 #define JEDEC_PARAM_PAGES 3
20 
21 /*
22  * Check if the NAND chip is JEDEC compliant, returns 1 if it is, 0 otherwise.
23  */
24 int nand_jedec_detect(struct nand_chip *chip)
25 {
26 	struct mtd_info *mtd = nand_to_mtd(chip);
27 	struct nand_memory_organization *memorg;
28 	struct nand_jedec_params *p;
29 	struct jedec_ecc_info *ecc;
30 	bool use_datain = false;
31 	int jedec_version = 0;
32 	char id[5];
33 	int i, val, ret;
34 	u16 crc;
35 
36 	memorg = nanddev_get_memorg(&chip->base);
37 
38 	/* Try JEDEC for unknown chip or LP */
39 	ret = nand_readid_op(chip, 0x40, id, sizeof(id));
40 	if (ret || strncmp(id, "JEDEC", sizeof(id)))
41 		return 0;
42 
43 	/* JEDEC chip: allocate a buffer to hold its parameter page */
44 	p = kzalloc(sizeof(*p), GFP_KERNEL);
45 	if (!p)
46 		return -ENOMEM;
47 
48 	if (!nand_has_exec_op(chip) ||
49 	    !nand_read_data_op(chip, p, sizeof(*p), true, true))
50 		use_datain = true;
51 
52 	for (i = 0; i < JEDEC_PARAM_PAGES; i++) {
53 		if (!i)
54 			ret = nand_read_param_page_op(chip, 0x40, p,
55 						      sizeof(*p));
56 		else if (use_datain)
57 			ret = nand_read_data_op(chip, p, sizeof(*p), true,
58 						false);
59 		else
60 			ret = nand_change_read_column_op(chip, sizeof(*p) * i,
61 							 p, sizeof(*p), true);
62 		if (ret) {
63 			ret = 0;
64 			goto free_jedec_param_page;
65 		}
66 
67 		crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)p, 510);
68 		if (crc == le16_to_cpu(p->crc))
69 			break;
70 	}
71 
72 	if (i == JEDEC_PARAM_PAGES) {
73 		pr_err("Could not find valid JEDEC parameter page; aborting\n");
74 		goto free_jedec_param_page;
75 	}
76 
77 	/* Check version */
78 	val = le16_to_cpu(p->revision);
79 	if (val & (1 << 2))
80 		jedec_version = 10;
81 	else if (val & (1 << 1))
82 		jedec_version = 1; /* vendor specific version */
83 
84 	if (!jedec_version) {
85 		pr_info("unsupported JEDEC version: %d\n", val);
86 		goto free_jedec_param_page;
87 	}
88 
89 	sanitize_string(p->manufacturer, sizeof(p->manufacturer));
90 	sanitize_string(p->model, sizeof(p->model));
91 	chip->parameters.model = kstrdup(p->model, GFP_KERNEL);
92 	if (!chip->parameters.model) {
93 		ret = -ENOMEM;
94 		goto free_jedec_param_page;
95 	}
96 
97 	memorg->pagesize = le32_to_cpu(p->byte_per_page);
98 	mtd->writesize = memorg->pagesize;
99 
100 	/* Please reference to the comment for nand_flash_detect_onfi. */
101 	memorg->pages_per_eraseblock =
102 			1 << (fls(le32_to_cpu(p->pages_per_block)) - 1);
103 	mtd->erasesize = memorg->pages_per_eraseblock * memorg->pagesize;
104 
105 	memorg->oobsize = le16_to_cpu(p->spare_bytes_per_page);
106 	mtd->oobsize = memorg->oobsize;
107 
108 	memorg->luns_per_target = p->lun_count;
109 	memorg->planes_per_lun = 1 << p->multi_plane_addr;
110 
111 	/* Please reference to the comment for nand_flash_detect_onfi. */
112 	memorg->eraseblocks_per_lun =
113 		1 << (fls(le32_to_cpu(p->blocks_per_lun)) - 1);
114 	memorg->bits_per_cell = p->bits_per_cell;
115 
116 	if (le16_to_cpu(p->features) & JEDEC_FEATURE_16_BIT_BUS)
117 		chip->options |= NAND_BUSWIDTH_16;
118 
119 	/* ECC info */
120 	ecc = &p->ecc_info[0];
121 
122 	if (ecc->codeword_size >= 9) {
123 		chip->base.eccreq.strength = ecc->ecc_bits;
124 		chip->base.eccreq.step_size = 1 << ecc->codeword_size;
125 	} else {
126 		pr_warn("Invalid codeword size\n");
127 	}
128 
129 	ret = 1;
130 
131 free_jedec_param_page:
132 	kfree(p);
133 	return ret;
134 }
135