cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

nand_jedec.c (3559B)

      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 */
     24int nand_jedec_detect(struct nand_chip *chip)
     25{
     26	struct nand_device *base = &chip->base;
     27	struct mtd_info *mtd = nand_to_mtd(chip);
     28	struct nand_memory_organization *memorg;
     29	struct nand_jedec_params *p;
     30	struct jedec_ecc_info *ecc;
     31	bool use_datain = false;
     32	int jedec_version = 0;
     33	char id[5];
     34	int i, val, ret;
     35	u16 crc;
     36
     37	memorg = nanddev_get_memorg(&chip->base);
     38
     39	/* Try JEDEC for unknown chip or LP */
     40	ret = nand_readid_op(chip, 0x40, id, sizeof(id));
     41	if (ret || strncmp(id, "JEDEC", sizeof(id)))
     42		return 0;
     43
     44	/* JEDEC chip: allocate a buffer to hold its parameter page */
     45	p = kzalloc(sizeof(*p), GFP_KERNEL);
     46	if (!p)
     47		return -ENOMEM;
     48
     49	if (!nand_has_exec_op(chip) ||
     50	    !nand_read_data_op(chip, p, sizeof(*p), true, true))
     51		use_datain = true;
     52
     53	for (i = 0; i < JEDEC_PARAM_PAGES; i++) {
     54		if (!i)
     55			ret = nand_read_param_page_op(chip, 0x40, p,
     56						      sizeof(*p));
     57		else if (use_datain)
     58			ret = nand_read_data_op(chip, p, sizeof(*p), true,
     59						false);
     60		else
     61			ret = nand_change_read_column_op(chip, sizeof(*p) * i,
     62							 p, sizeof(*p), true);
     63		if (ret) {
     64			ret = 0;
     65			goto free_jedec_param_page;
     66		}
     67
     68		crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)p, 510);
     69		if (crc == le16_to_cpu(p->crc))
     70			break;
     71	}
     72
     73	if (i == JEDEC_PARAM_PAGES) {
     74		pr_err("Could not find valid JEDEC parameter page; aborting\n");
     75		goto free_jedec_param_page;
     76	}
     77
     78	/* Check version */
     79	val = le16_to_cpu(p->revision);
     80	if (val & (1 << 2))
     81		jedec_version = 10;
     82	else if (val & (1 << 1))
     83		jedec_version = 1; /* vendor specific version */
     84
     85	if (!jedec_version) {
     86		pr_info("unsupported JEDEC version: %d\n", val);
     87		goto free_jedec_param_page;
     88	}
     89
     90	sanitize_string(p->manufacturer, sizeof(p->manufacturer));
     91	sanitize_string(p->model, sizeof(p->model));
     92	chip->parameters.model = kstrdup(p->model, GFP_KERNEL);
     93	if (!chip->parameters.model) {
     94		ret = -ENOMEM;
     95		goto free_jedec_param_page;
     96	}
     97
     98	memorg->pagesize = le32_to_cpu(p->byte_per_page);
     99	mtd->writesize = memorg->pagesize;
    100
    101	/* Please reference to the comment for nand_flash_detect_onfi. */
    102	memorg->pages_per_eraseblock =
    103			1 << (fls(le32_to_cpu(p->pages_per_block)) - 1);
    104	mtd->erasesize = memorg->pages_per_eraseblock * memorg->pagesize;
    105
    106	memorg->oobsize = le16_to_cpu(p->spare_bytes_per_page);
    107	mtd->oobsize = memorg->oobsize;
    108
    109	memorg->luns_per_target = p->lun_count;
    110	memorg->planes_per_lun = 1 << p->multi_plane_addr;
    111
    112	/* Please reference to the comment for nand_flash_detect_onfi. */
    113	memorg->eraseblocks_per_lun =
    114		1 << (fls(le32_to_cpu(p->blocks_per_lun)) - 1);
    115	memorg->bits_per_cell = p->bits_per_cell;
    116
    117	if (le16_to_cpu(p->features) & JEDEC_FEATURE_16_BIT_BUS)
    118		chip->options |= NAND_BUSWIDTH_16;
    119
    120	/* ECC info */
    121	ecc = &p->ecc_info[0];
    122
    123	if (ecc->codeword_size >= 9) {
    124		struct nand_ecc_props requirements = {
    125			.strength = ecc->ecc_bits,
    126			.step_size = 1 << ecc->codeword_size,
    127		};
    128
    129		nanddev_set_ecc_requirements(base, &requirements);
    130	} else {
    131		pr_warn("Invalid codeword size\n");
    132	}
    133
    134	ret = 1;
    135
    136free_jedec_param_page:
    137	kfree(p);
    138	return ret;
    139}