xref: /openbmc/linux/drivers/mtd/nand/spi/toshiba.c (revision 8b030a57)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2018 exceet electronics GmbH
4  * Copyright (c) 2018 Kontron Electronics GmbH
5  *
6  * Author: Frieder Schrempf <frieder.schrempf@kontron.de>
7  */
8 
9 #include <linux/device.h>
10 #include <linux/kernel.h>
11 #include <linux/mtd/spinand.h>
12 
13 #define SPINAND_MFR_TOSHIBA		0x98
14 #define TOSH_STATUS_ECC_HAS_BITFLIPS_T	(3 << 4)
15 
16 static SPINAND_OP_VARIANTS(read_cache_variants,
17 		SPINAND_PAGE_READ_FROM_CACHE_X4_OP(0, 1, NULL, 0),
18 		SPINAND_PAGE_READ_FROM_CACHE_X2_OP(0, 1, NULL, 0),
19 		SPINAND_PAGE_READ_FROM_CACHE_OP(true, 0, 1, NULL, 0),
20 		SPINAND_PAGE_READ_FROM_CACHE_OP(false, 0, 1, NULL, 0));
21 
22 static SPINAND_OP_VARIANTS(write_cache_variants,
23 		SPINAND_PROG_LOAD(true, 0, NULL, 0));
24 
25 static SPINAND_OP_VARIANTS(update_cache_variants,
26 		SPINAND_PROG_LOAD(false, 0, NULL, 0));
27 
28 static int tc58cvg2s0h_ooblayout_ecc(struct mtd_info *mtd, int section,
29 				     struct mtd_oob_region *region)
30 {
31 	if (section > 7)
32 		return -ERANGE;
33 
34 	region->offset = 128 + 16 * section;
35 	region->length = 16;
36 
37 	return 0;
38 }
39 
40 static int tc58cvg2s0h_ooblayout_free(struct mtd_info *mtd, int section,
41 				      struct mtd_oob_region *region)
42 {
43 	if (section > 0)
44 		return -ERANGE;
45 
46 	/* 2 bytes reserved for BBM */
47 	region->offset = 2;
48 	region->length = 126;
49 
50 	return 0;
51 }
52 
53 static const struct mtd_ooblayout_ops tc58cvg2s0h_ooblayout = {
54 	.ecc = tc58cvg2s0h_ooblayout_ecc,
55 	.free = tc58cvg2s0h_ooblayout_free,
56 };
57 
58 static int tc58cvg2s0h_ecc_get_status(struct spinand_device *spinand,
59 				      u8 status)
60 {
61 	struct nand_device *nand = spinand_to_nand(spinand);
62 	u8 mbf = 0;
63 	struct spi_mem_op op = SPINAND_GET_FEATURE_OP(0x30, &mbf);
64 
65 	switch (status & STATUS_ECC_MASK) {
66 	case STATUS_ECC_NO_BITFLIPS:
67 		return 0;
68 
69 	case STATUS_ECC_UNCOR_ERROR:
70 		return -EBADMSG;
71 
72 	case STATUS_ECC_HAS_BITFLIPS:
73 	case TOSH_STATUS_ECC_HAS_BITFLIPS_T:
74 		/*
75 		 * Let's try to retrieve the real maximum number of bitflips
76 		 * in order to avoid forcing the wear-leveling layer to move
77 		 * data around if it's not necessary.
78 		 */
79 		if (spi_mem_exec_op(spinand->spimem, &op))
80 			return nand->eccreq.strength;
81 
82 		mbf >>= 4;
83 
84 		if (WARN_ON(mbf > nand->eccreq.strength || !mbf))
85 			return nand->eccreq.strength;
86 
87 		return mbf;
88 
89 	default:
90 		break;
91 	}
92 
93 	return -EINVAL;
94 }
95 
96 static const struct spinand_info toshiba_spinand_table[] = {
97 	SPINAND_INFO("TC58CVG2S0H", 0xCD,
98 		     NAND_MEMORG(1, 4096, 256, 64, 2048, 1, 1, 1),
99 		     NAND_ECCREQ(8, 512),
100 		     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
101 					      &write_cache_variants,
102 					      &update_cache_variants),
103 		     SPINAND_HAS_QE_BIT,
104 		     SPINAND_ECCINFO(&tc58cvg2s0h_ooblayout,
105 				     tc58cvg2s0h_ecc_get_status)),
106 };
107 
108 static int toshiba_spinand_detect(struct spinand_device *spinand)
109 {
110 	u8 *id = spinand->id.data;
111 	int ret;
112 
113 	/*
114 	 * Toshiba SPI NAND read ID needs a dummy byte,
115 	 * so the first byte in id is garbage.
116 	 */
117 	if (id[1] != SPINAND_MFR_TOSHIBA)
118 		return 0;
119 
120 	ret = spinand_match_and_init(spinand, toshiba_spinand_table,
121 				     ARRAY_SIZE(toshiba_spinand_table),
122 				     id[2]);
123 	if (ret)
124 		return ret;
125 
126 	return 1;
127 }
128 
129 static const struct spinand_manufacturer_ops toshiba_spinand_manuf_ops = {
130 	.detect = toshiba_spinand_detect,
131 };
132 
133 const struct spinand_manufacturer toshiba_spinand_manufacturer = {
134 	.id = SPINAND_MFR_TOSHIBA,
135 	.name = "Toshiba",
136 	.ops = &toshiba_spinand_manuf_ops,
137 };
138