xref: /openbmc/linux/drivers/mtd/nand/raw/nand_amd.c (revision cd6d421e)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2017 Free Electrons
4  * Copyright (C) 2017 NextThing Co
5  *
6  * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
7  */
8 
9 #include "internals.h"
10 
11 static void amd_nand_decode_id(struct nand_chip *chip)
12 {
13 	struct mtd_info *mtd = nand_to_mtd(chip);
14 	struct nand_memory_organization *memorg;
15 
16 	memorg = nanddev_get_memorg(&chip->base);
17 
18 	nand_decode_ext_id(chip);
19 
20 	/*
21 	 * Check for Spansion/AMD ID + repeating 5th, 6th byte since
22 	 * some Spansion chips have erasesize that conflicts with size
23 	 * listed in nand_ids table.
24 	 * Data sheet (5 byte ID): Spansion S30ML-P ORNAND (p.39)
25 	 */
26 	if (chip->id.data[4] != 0x00 && chip->id.data[5] == 0x00 &&
27 	    chip->id.data[6] == 0x00 && chip->id.data[7] == 0x00 &&
28 	    memorg->pagesize == 512) {
29 		memorg->pages_per_eraseblock = 256;
30 		memorg->pages_per_eraseblock <<= ((chip->id.data[3] & 0x03) << 1);
31 		mtd->erasesize = memorg->pages_per_eraseblock *
32 				 memorg->pagesize;
33 	}
34 }
35 
36 static int amd_nand_init(struct nand_chip *chip)
37 {
38 	if (nand_is_slc(chip))
39 		/*
40 		 * According to the datasheet of some Cypress SLC NANDs,
41 		 * the bad block markers can be in the first, second or last
42 		 * page of a block. So let's check all three locations.
43 		 */
44 		chip->options |= NAND_BBM_FIRSTPAGE | NAND_BBM_SECONDPAGE |
45 				 NAND_BBM_LASTPAGE;
46 
47 	return 0;
48 }
49 
50 const struct nand_manufacturer_ops amd_nand_manuf_ops = {
51 	.detect = amd_nand_decode_id,
52 	.init = amd_nand_init,
53 };
54