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-rw-r--r--drivers/mtd/parsers/Kconfig8
-rw-r--r--drivers/mtd/parsers/Makefile1
-rw-r--r--drivers/mtd/parsers/sharpslpart.c398
3 files changed, 407 insertions, 0 deletions
diff --git a/drivers/mtd/parsers/Kconfig b/drivers/mtd/parsers/Kconfig
index d206b3c533bc..ee5ab994132f 100644
--- a/drivers/mtd/parsers/Kconfig
+++ b/drivers/mtd/parsers/Kconfig
@@ -6,3 +6,11 @@ config MTD_PARSER_TRX
 	  may contain up to 3/4 partitions (depending on the version).
 	  This driver will parse TRX header and report at least two partitions:
 	  kernel and rootfs.
+
+config MTD_SHARPSL_PARTS
+	tristate "Sharp SL Series NAND flash partition parser"
+	depends on MTD_NAND_SHARPSL || MTD_NAND_TMIO || COMPILE_TEST
+	help
+	  This provides the read-only FTL logic necessary to read the partition
+	  table from the NAND flash of Sharp SL Series (Zaurus) and the MTD
+	  partition parser using this code.
diff --git a/drivers/mtd/parsers/Makefile b/drivers/mtd/parsers/Makefile
index 4d9024e0be3b..5b1bcc3d90d9 100644
--- a/drivers/mtd/parsers/Makefile
+++ b/drivers/mtd/parsers/Makefile
@@ -1 +1,2 @@
 obj-$(CONFIG_MTD_PARSER_TRX)		+= parser_trx.o
+obj-$(CONFIG_MTD_SHARPSL_PARTS)		+= sharpslpart.o
diff --git a/drivers/mtd/parsers/sharpslpart.c b/drivers/mtd/parsers/sharpslpart.c
new file mode 100644
index 000000000000..5fe0079ea5ed
--- /dev/null
+++ b/drivers/mtd/parsers/sharpslpart.c
@@ -0,0 +1,398 @@
+/*
+ * sharpslpart.c - MTD partition parser for NAND flash using the SHARP FTL
+ * for logical addressing, as used on the PXA models of the SHARP SL Series.
+ *
+ * Copyright (C) 2017 Andrea Adami <andrea.adami@gmail.com>
+ *
+ * Based on SHARP GPL 2.4 sources:
+ *   http://support.ezaurus.com/developer/source/source_dl.asp
+ *     drivers/mtd/nand/sharp_sl_logical.c
+ *     linux/include/asm-arm/sharp_nand_logical.h
+ *
+ * Copyright (C) 2002 SHARP
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/bitops.h>
+#include <linux/sizes.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+
+/* oob structure */
+#define NAND_NOOB_LOGADDR_00		8
+#define NAND_NOOB_LOGADDR_01		9
+#define NAND_NOOB_LOGADDR_10		10
+#define NAND_NOOB_LOGADDR_11		11
+#define NAND_NOOB_LOGADDR_20		12
+#define NAND_NOOB_LOGADDR_21		13
+
+#define BLOCK_IS_RESERVED		0xffff
+#define BLOCK_UNMASK_COMPLEMENT		1
+
+/* factory defaults */
+#define SHARPSL_NAND_PARTS		3
+#define SHARPSL_FTL_PART_SIZE		(7 * SZ_1M)
+#define SHARPSL_PARTINFO1_LADDR		0x00060000
+#define SHARPSL_PARTINFO2_LADDR		0x00064000
+
+#define BOOT_MAGIC			0x424f4f54
+#define FSRO_MAGIC			0x4653524f
+#define FSRW_MAGIC			0x46535257
+
+/**
+ * struct sharpsl_ftl - Sharp FTL Logical Table
+ * @logmax:		number of logical blocks
+ * @log2phy:		the logical-to-physical table
+ *
+ * Structure containing the logical-to-physical translation table
+ * used by the SHARP SL FTL.
+ */
+struct sharpsl_ftl {
+	unsigned int logmax;
+	unsigned int *log2phy;
+};
+
+/* verify that the OOB bytes 8 to 15 are free and available for the FTL */
+static int sharpsl_nand_check_ooblayout(struct mtd_info *mtd)
+{
+	u8 freebytes = 0;
+	int section = 0;
+
+	while (true) {
+		struct mtd_oob_region oobfree = { };
+		int ret, i;
+
+		ret = mtd_ooblayout_free(mtd, section++, &oobfree);
+		if (ret)
+			break;
+
+		if (!oobfree.length || oobfree.offset > 15 ||
+		    (oobfree.offset + oobfree.length) < 8)
+			continue;
+
+		i = oobfree.offset >= 8 ? oobfree.offset : 8;
+		for (; i < oobfree.offset + oobfree.length && i < 16; i++)
+			freebytes |= BIT(i - 8);
+
+		if (freebytes == 0xff)
+			return 0;
+	}
+
+	return -ENOTSUPP;
+}
+
+static int sharpsl_nand_read_oob(struct mtd_info *mtd, loff_t offs, u8 *buf)
+{
+	struct mtd_oob_ops ops = { };
+	int ret;
+
+	ops.mode = MTD_OPS_PLACE_OOB;
+	ops.ooblen = mtd->oobsize;
+	ops.oobbuf = buf;
+
+	ret = mtd_read_oob(mtd, offs, &ops);
+	if (ret != 0 || mtd->oobsize != ops.oobretlen)
+		return -1;
+
+	return 0;
+}
+
+/*
+ * The logical block number assigned to a physical block is stored in the OOB
+ * of the first page, in 3 16-bit copies with the following layout:
+ *
+ * 01234567 89abcdef
+ * -------- --------
+ * ECC BB   xyxyxy
+ *
+ * When reading we check that the first two copies agree.
+ * In case of error, matching is tried using the following pairs.
+ * Reserved values 0xffff mean the block is kept for wear leveling.
+ *
+ * 01234567 89abcdef
+ * -------- --------
+ * ECC BB   xyxy    oob[8]==oob[10] && oob[9]==oob[11]   -> byte0=8   byte1=9
+ * ECC BB     xyxy  oob[10]==oob[12] && oob[11]==oob[13] -> byte0=10  byte1=11
+ * ECC BB   xy  xy  oob[12]==oob[8] && oob[13]==oob[9]   -> byte0=12  byte1=13
+ */
+static int sharpsl_nand_get_logical_num(u8 *oob)
+{
+	u16 us;
+	int good0, good1;
+
+	if (oob[NAND_NOOB_LOGADDR_00] == oob[NAND_NOOB_LOGADDR_10] &&
+	    oob[NAND_NOOB_LOGADDR_01] == oob[NAND_NOOB_LOGADDR_11]) {
+		good0 = NAND_NOOB_LOGADDR_00;
+		good1 = NAND_NOOB_LOGADDR_01;
+	} else if (oob[NAND_NOOB_LOGADDR_10] == oob[NAND_NOOB_LOGADDR_20] &&
+		   oob[NAND_NOOB_LOGADDR_11] == oob[NAND_NOOB_LOGADDR_21]) {
+		good0 = NAND_NOOB_LOGADDR_10;
+		good1 = NAND_NOOB_LOGADDR_11;
+	} else if (oob[NAND_NOOB_LOGADDR_20] == oob[NAND_NOOB_LOGADDR_00] &&
+		   oob[NAND_NOOB_LOGADDR_21] == oob[NAND_NOOB_LOGADDR_01]) {
+		good0 = NAND_NOOB_LOGADDR_20;
+		good1 = NAND_NOOB_LOGADDR_21;
+	} else {
+		return -EINVAL;
+	}
+
+	us = oob[good0] | oob[good1] << 8;
+
+	/* parity check */
+	if (hweight16(us) & BLOCK_UNMASK_COMPLEMENT)
+		return -EINVAL;
+
+	/* reserved */
+	if (us == BLOCK_IS_RESERVED)
+		return BLOCK_IS_RESERVED;
+
+	return (us >> 1) & GENMASK(9, 0);
+}
+
+static int sharpsl_nand_init_ftl(struct mtd_info *mtd, struct sharpsl_ftl *ftl)
+{
+	unsigned int block_num, log_num, phymax;
+	loff_t block_adr;
+	u8 *oob;
+	int i, ret;
+
+	oob = kzalloc(mtd->oobsize, GFP_KERNEL);
+	if (!oob)
+		return -ENOMEM;
+
+	phymax = mtd_div_by_eb(SHARPSL_FTL_PART_SIZE, mtd);
+
+	/* FTL reserves 5% of the blocks + 1 spare  */
+	ftl->logmax = ((phymax * 95) / 100) - 1;
+
+	ftl->log2phy = kmalloc_array(ftl->logmax, sizeof(*ftl->log2phy),
+				     GFP_KERNEL);
+	if (!ftl->log2phy) {
+		ret = -ENOMEM;
+		goto exit;
+	}
+
+	/* initialize ftl->log2phy */
+	for (i = 0; i < ftl->logmax; i++)
+		ftl->log2phy[i] = UINT_MAX;
+
+	/* create physical-logical table */
+	for (block_num = 0; block_num < phymax; block_num++) {
+		block_adr = block_num * mtd->erasesize;
+
+		if (mtd_block_isbad(mtd, block_adr))
+			continue;
+
+		if (sharpsl_nand_read_oob(mtd, block_adr, oob))
+			continue;
+
+		/* get logical block */
+		log_num = sharpsl_nand_get_logical_num(oob);
+
+		/* cut-off errors and skip the out-of-range values */
+		if (log_num > 0 && log_num < ftl->logmax) {
+			if (ftl->log2phy[log_num] == UINT_MAX)
+				ftl->log2phy[log_num] = block_num;
+		}
+	}
+
+	pr_info("Sharp SL FTL: %d blocks used (%d logical, %d reserved)\n",
+		phymax, ftl->logmax, phymax - ftl->logmax);
+
+	ret = 0;
+exit:
+	kfree(oob);
+	return ret;
+}
+
+void sharpsl_nand_cleanup_ftl(struct sharpsl_ftl *ftl)
+{
+	kfree(ftl->log2phy);
+}
+
+static int sharpsl_nand_read_laddr(struct mtd_info *mtd,
+				   loff_t from,
+				   size_t len,
+				   void *buf,
+				   struct sharpsl_ftl *ftl)
+{
+	unsigned int log_num, final_log_num;
+	unsigned int block_num;
+	loff_t block_adr;
+	loff_t block_ofs;
+	size_t retlen;
+	int err;
+
+	log_num = mtd_div_by_eb((u32)from, mtd);
+	final_log_num = mtd_div_by_eb(((u32)from + len - 1), mtd);
+
+	if (len <= 0 || log_num >= ftl->logmax || final_log_num > log_num)
+		return -EINVAL;
+
+	block_num = ftl->log2phy[log_num];
+	block_adr = block_num * mtd->erasesize;
+	block_ofs = mtd_mod_by_eb((u32)from, mtd);
+
+	err = mtd_read(mtd, block_adr + block_ofs, len, &retlen, buf);
+	/* Ignore corrected ECC errors */
+	if (mtd_is_bitflip(err))
+		err = 0;
+
+	if (!err && retlen != len)
+		err = -EIO;
+
+	if (err)
+		pr_err("sharpslpart: error, read failed at %#llx\n",
+		       block_adr + block_ofs);
+
+	return err;
+}
+
+/*
+ * MTD Partition Parser
+ *
+ * Sample values read from SL-C860
+ *
+ * # cat /proc/mtd
+ * dev:    size   erasesize  name
+ * mtd0: 006d0000 00020000 "Filesystem"
+ * mtd1: 00700000 00004000 "smf"
+ * mtd2: 03500000 00004000 "root"
+ * mtd3: 04400000 00004000 "home"
+ *
+ * PARTITIONINFO1
+ * 0x00060000: 00 00 00 00 00 00 70 00 42 4f 4f 54 00 00 00 00  ......p.BOOT....
+ * 0x00060010: 00 00 70 00 00 00 c0 03 46 53 52 4f 00 00 00 00  ..p.....FSRO....
+ * 0x00060020: 00 00 c0 03 00 00 00 04 46 53 52 57 00 00 00 00  ........FSRW....
+ */
+struct sharpsl_nand_partinfo {
+	__le32 start;
+	__le32 end;
+	__be32 magic;
+	u32 reserved;
+};
+
+static int sharpsl_nand_read_partinfo(struct mtd_info *master,
+				      loff_t from,
+				      size_t len,
+				      struct sharpsl_nand_partinfo *buf,
+				      struct sharpsl_ftl *ftl)
+{
+	int ret;
+
+	ret = sharpsl_nand_read_laddr(master, from, len, buf, ftl);
+	if (ret)
+		return ret;
+
+	/* check for magics */
+	if (be32_to_cpu(buf[0].magic) != BOOT_MAGIC ||
+	    be32_to_cpu(buf[1].magic) != FSRO_MAGIC ||
+	    be32_to_cpu(buf[2].magic) != FSRW_MAGIC) {
+		pr_err("sharpslpart: magic values mismatch\n");
+		return -EINVAL;
+	}
+
+	/* fixup for hardcoded value 64 MiB (for older models) */
+	buf[2].end = cpu_to_le32(master->size);
+
+	/* extra sanity check */
+	if (le32_to_cpu(buf[0].end) <= le32_to_cpu(buf[0].start) ||
+	    le32_to_cpu(buf[1].start) < le32_to_cpu(buf[0].end) ||
+	    le32_to_cpu(buf[1].end) <= le32_to_cpu(buf[1].start) ||
+	    le32_to_cpu(buf[2].start) < le32_to_cpu(buf[1].end) ||
+	    le32_to_cpu(buf[2].end) <= le32_to_cpu(buf[2].start)) {
+		pr_err("sharpslpart: partition sizes mismatch\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int sharpsl_parse_mtd_partitions(struct mtd_info *master,
+					const struct mtd_partition **pparts,
+					struct mtd_part_parser_data *data)
+{
+	struct sharpsl_ftl ftl;
+	struct sharpsl_nand_partinfo buf[SHARPSL_NAND_PARTS];
+	struct mtd_partition *sharpsl_nand_parts;
+	int err;
+
+	/* check that OOB bytes 8 to 15 used by the FTL are actually free */
+	err = sharpsl_nand_check_ooblayout(master);
+	if (err)
+		return err;
+
+	/* init logical mgmt (FTL) */
+	err = sharpsl_nand_init_ftl(master, &ftl);
+	if (err)
+		return err;
+
+	/* read and validate first partition table */
+	pr_info("sharpslpart: try reading first partition table\n");
+	err = sharpsl_nand_read_partinfo(master,
+					 SHARPSL_PARTINFO1_LADDR,
+					 sizeof(buf), buf, &ftl);
+	if (err) {
+		/* fallback: read second partition table */
+		pr_warn("sharpslpart: first partition table is invalid, retry using the second\n");
+		err = sharpsl_nand_read_partinfo(master,
+						 SHARPSL_PARTINFO2_LADDR,
+						 sizeof(buf), buf, &ftl);
+	}
+
+	/* cleanup logical mgmt (FTL) */
+	sharpsl_nand_cleanup_ftl(&ftl);
+
+	if (err) {
+		pr_err("sharpslpart: both partition tables are invalid\n");
+		return err;
+	}
+
+	sharpsl_nand_parts = kzalloc(sizeof(*sharpsl_nand_parts) *
+				     SHARPSL_NAND_PARTS, GFP_KERNEL);
+	if (!sharpsl_nand_parts)
+		return -ENOMEM;
+
+	/* original names */
+	sharpsl_nand_parts[0].name = "smf";
+	sharpsl_nand_parts[0].offset = le32_to_cpu(buf[0].start);
+	sharpsl_nand_parts[0].size = le32_to_cpu(buf[0].end) -
+				     le32_to_cpu(buf[0].start);
+
+	sharpsl_nand_parts[1].name = "root";
+	sharpsl_nand_parts[1].offset = le32_to_cpu(buf[1].start);
+	sharpsl_nand_parts[1].size = le32_to_cpu(buf[1].end) -
+				     le32_to_cpu(buf[1].start);
+
+	sharpsl_nand_parts[2].name = "home";
+	sharpsl_nand_parts[2].offset = le32_to_cpu(buf[2].start);
+	sharpsl_nand_parts[2].size = le32_to_cpu(buf[2].end) -
+				     le32_to_cpu(buf[2].start);
+
+	*pparts = sharpsl_nand_parts;
+	return SHARPSL_NAND_PARTS;
+}
+
+static struct mtd_part_parser sharpsl_mtd_parser = {
+	.parse_fn = sharpsl_parse_mtd_partitions,
+	.name = "sharpslpart",
+};
+module_mtd_part_parser(sharpsl_mtd_parser);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Andrea Adami <andrea.adami@gmail.com>");
+MODULE_DESCRIPTION("MTD partitioning for NAND flash on Sharp SL Series");