xref: /openbmc/linux/drivers/mtd/nand/raw/nand_amd.c (revision addee42a)
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 
18 #include <linux/mtd/rawnand.h>
19 
20 static void amd_nand_decode_id(struct nand_chip *chip)
21 {
22 	struct mtd_info *mtd = nand_to_mtd(chip);
23 
24 	nand_decode_ext_id(chip);
25 
26 	/*
27 	 * Check for Spansion/AMD ID + repeating 5th, 6th byte since
28 	 * some Spansion chips have erasesize that conflicts with size
29 	 * listed in nand_ids table.
30 	 * Data sheet (5 byte ID): Spansion S30ML-P ORNAND (p.39)
31 	 */
32 	if (chip->id.data[4] != 0x00 && chip->id.data[5] == 0x00 &&
33 	    chip->id.data[6] == 0x00 && chip->id.data[7] == 0x00 &&
34 	    mtd->writesize == 512) {
35 		mtd->erasesize = 128 * 1024;
36 		mtd->erasesize <<= ((chip->id.data[3] & 0x03) << 1);
37 	}
38 }
39 
40 static int amd_nand_init(struct nand_chip *chip)
41 {
42 	if (nand_is_slc(chip))
43 		chip->bbt_options |= NAND_BBT_SCAN2NDPAGE;
44 
45 	return 0;
46 }
47 
48 const struct nand_manufacturer_ops amd_nand_manuf_ops = {
49 	.detect = amd_nand_decode_id,
50 	.init = amd_nand_init,
51 };
52