[RFC PATCH 33/34] mtd: spi-nor: Move SFDP parsing code out of core.c

[Boris Brezillon <boris.brezillon@xxxxxxxxxxx>]

It make the core file a bit smaller and provide better separation
between the SFDP parsing and core logic.

Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx>
---
 drivers/mtd/spi-nor/Makefile    |   2 +-
 drivers/mtd/spi-nor/core.c      | 870 +-------------------------------
 drivers/mtd/spi-nor/internals.h |  15 +
 drivers/mtd/spi-nor/sfdp.c      | 859 +++++++++++++++++++++++++++++++
 4 files changed, 885 insertions(+), 861 deletions(-)
 create mode 100644 drivers/mtd/spi-nor/sfdp.c

diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
index 07ded3a76623..1ae2ef1fbfc3 100644
--- a/drivers/mtd/spi-nor/Makefile
+++ b/drivers/mtd/spi-nor/Makefile
@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
-spi-nor-objs			:= core.o
+spi-nor-objs			:= core.o sfdp.o
 spi-nor-objs			+= atmel.o
 spi-nor-objs			+= catalyst.o
 spi-nor-objs			+= eon.o
diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index 6ed562bddddb..9665f4d3ec19 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -15,7 +15,6 @@
 #include <linux/math64.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>
-#include <linux/sort.h>
 
 #include <linux/mtd/mtd.h>
 #include <linux/of_platform.h>
@@ -465,7 +464,7 @@ spi_nor_find_best_erase_type(const struct spi_nor_erase_map *map,
  *
  * Return: the next spi nor region or NULL if last region.
  */
-static struct spi_nor_erase_region *
+struct spi_nor_erase_region *
 spi_nor_region_next(struct spi_nor_erase_region *region)
 {
 	if (spi_nor_region_is_last(region))
@@ -1211,7 +1210,7 @@ static int legacy_quad_enable(struct spi_nor *nor)
  *
  * Return: 0 on success, -errno otherwise.
  */
-static int sr2_bit1_no_read_quad_enable(struct spi_nor *nor)
+int sr2_bit1_no_read_quad_enable(struct spi_nor *nor)
 {
 	u8 sr_cr[2];
 	int ret;
@@ -1241,7 +1240,7 @@ static int sr2_bit1_no_read_quad_enable(struct spi_nor *nor)
  *
  * Return: 0 on success, -errno otherwise.
  */
-static int sr2_bit1_read_quad_enable(struct spi_nor *nor)
+int sr2_bit1_read_quad_enable(struct spi_nor *nor)
 {
 	struct device *dev = nor->dev;
 	u8 sr_cr[2];
@@ -1293,7 +1292,7 @@ static int sr2_bit1_read_quad_enable(struct spi_nor *nor)
  *
  * Return: 0 on success, -errno otherwise.
  */
-static int sr2_bit7_quad_enable(struct spi_nor *nor)
+int sr2_bit7_quad_enable(struct spi_nor *nor)
 {
 	u8 sr2;
 	int ret;
@@ -1538,7 +1537,7 @@ static int spi_nor_hwcaps2cmd(u32 hwcaps, const int table[][2], size_t size)
 	return -EINVAL;
 }
 
-static int spi_nor_hwcaps_read2cmd(u32 hwcaps)
+int spi_nor_hwcaps_read2cmd(u32 hwcaps)
 {
 	static const int hwcaps_read2cmd[][2] = {
 		{ SNOR_HWCAPS_READ,		SNOR_CMD_READ },
@@ -1594,7 +1593,7 @@ static int spi_nor_hwcaps_pp2cmd(u32 hwcaps)
  *
  * Return: 0 on success, -errno otherwise.
  */
-static int spi_nor_read_raw(struct spi_nor *nor, u32 addr, size_t len, u8 *buf)
+int spi_nor_read_raw(struct spi_nor *nor, u32 addr, size_t len, u8 *buf)
 {
 	int ret;
 
@@ -1612,189 +1611,14 @@ static int spi_nor_read_raw(struct spi_nor *nor, u32 addr, size_t len, u8 *buf)
 	return 0;
 }
 
-/**
- * spi_nor_read_sfdp() - read Serial Flash Discoverable Parameters.
- * @nor:	pointer to a 'struct spi_nor'
- * @addr:	offset in the SFDP area to start reading data from
- * @len:	number of bytes to read
- * @buf:	buffer where the SFDP data are copied into (dma-safe memory)
- *
- * Whatever the actual numbers of bytes for address and dummy cycles are
- * for (Fast) Read commands, the Read SFDP (5Ah) instruction is always
- * followed by a 3-byte address and 8 dummy clock cycles.
- *
- * Return: 0 on success, -errno otherwise.
- */
-static int spi_nor_read_sfdp(struct spi_nor *nor, u32 addr,
-			     size_t len, void *buf)
-{
-	u8 addr_width, read_opcode, read_dummy;
-	int ret;
-
-	read_opcode = nor->read_opcode;
-	addr_width = nor->addr_width;
-	read_dummy = nor->read_dummy;
-
-	nor->read_opcode = SPINOR_OP_RDSFDP;
-	nor->addr_width = 3;
-	nor->read_dummy = 8;
-
-	ret = spi_nor_read_raw(nor, addr, len, buf);
-
-	nor->read_opcode = read_opcode;
-	nor->addr_width = addr_width;
-	nor->read_dummy = read_dummy;
-
-	return ret;
-}
-
-/**
- * spi_nor_read_sfdp_dma_unsafe() - read Serial Flash Discoverable Parameters.
- * @nor:	pointer to a 'struct spi_nor'
- * @addr:	offset in the SFDP area to start reading data from
- * @len:	number of bytes to read
- * @buf:	buffer where the SFDP data are copied into
- *
- * Wrap spi_nor_read_sfdp() using a kmalloc'ed bounce buffer as @buf is now not
- * guaranteed to be dma-safe.
- *
- * Return: -ENOMEM if kmalloc() fails, the return code of spi_nor_read_sfdp()
- *          otherwise.
- */
-static int spi_nor_read_sfdp_dma_unsafe(struct spi_nor *nor, u32 addr,
-					size_t len, void *buf)
-{
-	void *dma_safe_buf;
-	int ret;
-
-	dma_safe_buf = kmalloc(len, GFP_KERNEL);
-	if (!dma_safe_buf)
-		return -ENOMEM;
-
-	ret = spi_nor_read_sfdp(nor, addr, len, dma_safe_buf);
-	memcpy(buf, dma_safe_buf, len);
-	kfree(dma_safe_buf);
-
-	return ret;
-}
-
-/* Fast Read settings. */
-
-static void
-spi_nor_set_read_settings_from_bfpt(struct spi_nor_read_command *read,
-				    u16 half,
-				    enum spi_nor_protocol proto)
-{
-	read->num_mode_clocks = (half >> 5) & 0x07;
-	read->num_wait_states = (half >> 0) & 0x1f;
-	read->opcode = (half >> 8) & 0xff;
-	read->proto = proto;
-}
-
-struct sfdp_bfpt_read {
-	/* The Fast Read x-y-z hardware capability in params->hwcaps.mask. */
-	u32			hwcaps;
-
-	/*
-	 * The <supported_bit> bit in <supported_dword> BFPT DWORD tells us
-	 * whether the Fast Read x-y-z command is supported.
-	 */
-	u32			supported_dword;
-	u32			supported_bit;
-
-	/*
-	 * The half-word at offset <setting_shift> in <setting_dword> BFPT DWORD
-	 * encodes the op code, the number of mode clocks and the number of wait
-	 * states to be used by Fast Read x-y-z command.
-	 */
-	u32			settings_dword;
-	u32			settings_shift;
-
-	/* The SPI protocol for this Fast Read x-y-z command. */
-	enum spi_nor_protocol	proto;
-};
-
-static const struct sfdp_bfpt_read sfdp_bfpt_reads[] = {
-	/* Fast Read 1-1-2 */
-	{
-		SNOR_HWCAPS_READ_1_1_2,
-		BFPT_DWORD(1), BIT(16),	/* Supported bit */
-		BFPT_DWORD(4), 0,	/* Settings */
-		SNOR_PROTO_1_1_2,
-	},
-
-	/* Fast Read 1-2-2 */
-	{
-		SNOR_HWCAPS_READ_1_2_2,
-		BFPT_DWORD(1), BIT(20),	/* Supported bit */
-		BFPT_DWORD(4), 16,	/* Settings */
-		SNOR_PROTO_1_2_2,
-	},
-
-	/* Fast Read 2-2-2 */
-	{
-		SNOR_HWCAPS_READ_2_2_2,
-		BFPT_DWORD(5),  BIT(0),	/* Supported bit */
-		BFPT_DWORD(6), 16,	/* Settings */
-		SNOR_PROTO_2_2_2,
-	},
-
-	/* Fast Read 1-1-4 */
-	{
-		SNOR_HWCAPS_READ_1_1_4,
-		BFPT_DWORD(1), BIT(22),	/* Supported bit */
-		BFPT_DWORD(3), 16,	/* Settings */
-		SNOR_PROTO_1_1_4,
-	},
-
-	/* Fast Read 1-4-4 */
-	{
-		SNOR_HWCAPS_READ_1_4_4,
-		BFPT_DWORD(1), BIT(21),	/* Supported bit */
-		BFPT_DWORD(3), 0,	/* Settings */
-		SNOR_PROTO_1_4_4,
-	},
-
-	/* Fast Read 4-4-4 */
-	{
-		SNOR_HWCAPS_READ_4_4_4,
-		BFPT_DWORD(5), BIT(4),	/* Supported bit */
-		BFPT_DWORD(7), 16,	/* Settings */
-		SNOR_PROTO_4_4_4,
-	},
-};
-
-struct sfdp_bfpt_erase {
-	/*
-	 * The half-word at offset <shift> in DWORD <dwoard> encodes the
-	 * op code and erase sector size to be used by Sector Erase commands.
-	 */
-	u32			dword;
-	u32			shift;
-};
-
-static const struct sfdp_bfpt_erase sfdp_bfpt_erases[] = {
-	/* Erase Type 1 in DWORD8 bits[15:0] */
-	{BFPT_DWORD(8), 0},
-
-	/* Erase Type 2 in DWORD8 bits[31:16] */
-	{BFPT_DWORD(8), 16},
-
-	/* Erase Type 3 in DWORD9 bits[15:0] */
-	{BFPT_DWORD(9), 0},
-
-	/* Erase Type 4 in DWORD9 bits[31:16] */
-	{BFPT_DWORD(9), 16},
-};
-
 /**
  * spi_nor_set_erase_type() - set a SPI NOR erase type
  * @erase:	pointer to a structure that describes a SPI NOR erase type
  * @size:	the size of the sector/block erased by the erase type
  * @opcode:	the SPI command op code to erase the sector/block
  */
-static void spi_nor_set_erase_type(struct spi_nor_erase_type *erase,
-				   u32 size, u8 opcode)
+void spi_nor_set_erase_type(struct spi_nor_erase_type *erase, u32 size,
+			    u8 opcode)
 {
 	erase->size = size;
 	erase->opcode = opcode;
@@ -1803,82 +1627,6 @@ static void spi_nor_set_erase_type(struct spi_nor_erase_type *erase,
 	erase->size_mask = (1 << erase->size_shift) - 1;
 }
 
-/**
- * spi_nor_set_erase_settings_from_bfpt() - set erase type settings from BFPT
- * @erase:	pointer to a structure that describes a SPI NOR erase type
- * @size:	the size of the sector/block erased by the erase type
- * @opcode:	the SPI command op code to erase the sector/block
- * @i:		erase type index as sorted in the Basic Flash Parameter Table
- *
- * The supported Erase Types will be sorted at init in ascending order, with
- * the smallest Erase Type size being the first member in the erase_type array
- * of the spi_nor_erase_map structure. Save the Erase Type index as sorted in
- * the Basic Flash Parameter Table since it will be used later on to
- * synchronize with the supported Erase Types defined in SFDP optional tables.
- */
-static void
-spi_nor_set_erase_settings_from_bfpt(struct spi_nor_erase_type *erase,
-				     u32 size, u8 opcode, u8 i)
-{
-	erase->idx = i;
-	spi_nor_set_erase_type(erase, size, opcode);
-}
-
-/**
- * spi_nor_map_cmp_erase_type() - compare the map's erase types by size
- * @l:	member in the left half of the map's erase_type array
- * @r:	member in the right half of the map's erase_type array
- *
- * Comparison function used in the sort() call to sort in ascending order the
- * map's erase types, the smallest erase type size being the first member in the
- * sorted erase_type array.
- *
- * Return: the result of @l->size - @r->size
- */
-static int spi_nor_map_cmp_erase_type(const void *l, const void *r)
-{
-	const struct spi_nor_erase_type *left = l, *right = r;
-
-	return left->size - right->size;
-}
-
-/**
- * spi_nor_regions_sort_erase_types() - sort erase types in each region
- * @map:	the erase map of the SPI NOR
- *
- * Function assumes that the erase types defined in the erase map are already
- * sorted in ascending order, with the smallest erase type size being the first
- * member in the erase_type array. It replicates the sort done for the map's
- * erase types. Each region's erase bitmask will indicate which erase types are
- * supported from the sorted erase types defined in the erase map.
- * Sort the all region's erase type at init in order to speed up the process of
- * finding the best erase command at runtime.
- */
-static void spi_nor_regions_sort_erase_types(struct spi_nor_erase_map *map)
-{
-	struct spi_nor_erase_region *region = map->regions;
-	struct spi_nor_erase_type *erase_type = map->erase_type;
-	int i;
-	u8 region_erase_mask, sorted_erase_mask;
-
-	while (region) {
-		region_erase_mask = region->offset & SNOR_ERASE_TYPE_MASK;
-
-		/* Replicate the sort done for the map's erase types. */
-		sorted_erase_mask = 0;
-		for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++)
-			if (erase_type[i].size &&
-			    region_erase_mask & BIT(erase_type[i].idx))
-				sorted_erase_mask |= BIT(i);
-
-		/* Overwrite erase mask. */
-		region->offset = (region->offset & ~SNOR_ERASE_TYPE_MASK) |
-				 sorted_erase_mask;
-
-		region = spi_nor_region_next(region);
-	}
-}
-
 /**
  * spi_nor_init_uniform_erase_map() - Initialize uniform erase map
  * @map:		the erase map of the SPI NOR
@@ -1886,8 +1634,8 @@ static void spi_nor_regions_sort_erase_types(struct spi_nor_erase_map *map)
  *			flash memory
  * @flash_size:		the spi nor flash memory size
  */
-static void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
-					   u8 erase_mask, u64 flash_size)
+void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
+				    u8 erase_mask, u64 flash_size)
 {
 	/* Offset 0 with erase_mask and SNOR_LAST_REGION bit set */
 	map->uniform_region.offset = (erase_mask & SNOR_ERASE_TYPE_MASK) |
@@ -1897,604 +1645,6 @@ static void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
 	map->uniform_erase_type = erase_mask;
 }
 
-static int
-spi_nor_post_bfpt_fixups(struct spi_nor *nor,
-			 const struct sfdp_parameter_header *bfpt_header,
-			 const struct sfdp_bfpt *bfpt,
-			 struct spi_nor_flash_parameter *params)
-{
-	int ret;
-
-	if (nor->manufacturer && nor->manufacturer->fixups &&
-	    nor->manufacturer->fixups->post_bfpt) {
-		ret = nor->manufacturer->fixups->post_bfpt(nor, bfpt_header,
-							   bfpt, params);
-		if (ret)
-			return ret;
-	}
-
-	if (nor->info->fixups && nor->info->fixups->post_bfpt) {
-		ret = nor->info->fixups->post_bfpt(nor, bfpt_header, bfpt,
-						   params);
-		if (ret)
-			return ret;
-	}
-
-	return 0;
-}
-
-/**
- * spi_nor_parse_bfpt() - read and parse the Basic Flash Parameter Table.
- * @nor:		pointer to a 'struct spi_nor'
- * @bfpt_header:	pointer to the 'struct sfdp_parameter_header' describing
- *			the Basic Flash Parameter Table length and version
- * @params:		pointer to the 'struct spi_nor_flash_parameter' to be
- *			filled
- *
- * The Basic Flash Parameter Table is the main and only mandatory table as
- * defined by the SFDP (JESD216) specification.
- * It provides us with the total size (memory density) of the data array and
- * the number of address bytes for Fast Read, Page Program and Sector Erase
- * commands.
- * For Fast READ commands, it also gives the number of mode clock cycles and
- * wait states (regrouped in the number of dummy clock cycles) for each
- * supported instruction op code.
- * For Page Program, the page size is now available since JESD216 rev A, however
- * the supported instruction op codes are still not provided.
- * For Sector Erase commands, this table stores the supported instruction op
- * codes and the associated sector sizes.
- * Finally, the Quad Enable Requirements (QER) are also available since JESD216
- * rev A. The QER bits encode the manufacturer dependent procedure to be
- * executed to set the Quad Enable (QE) bit in some internal register of the
- * Quad SPI memory. Indeed the QE bit, when it exists, must be set before
- * sending any Quad SPI command to the memory. Actually, setting the QE bit
- * tells the memory to reassign its WP# and HOLD#/RESET# pins to functions IO2
- * and IO3 hence enabling 4 (Quad) I/O lines.
- *
- * Return: 0 on success, -errno otherwise.
- */
-static int spi_nor_parse_bfpt(struct spi_nor *nor,
-			      const struct sfdp_parameter_header *bfpt_header,
-			      struct spi_nor_flash_parameter *params)
-{
-	struct spi_nor_erase_map *map = &nor->erase_map;
-	struct spi_nor_erase_type *erase_type = map->erase_type;
-	struct sfdp_bfpt bfpt;
-	size_t len;
-	int i, cmd, err;
-	u32 addr;
-	u16 half;
-	u8 erase_mask;
-
-	/* JESD216 Basic Flash Parameter Table length is at least 9 DWORDs. */
-	if (bfpt_header->length < BFPT_DWORD_MAX_JESD216)
-		return -EINVAL;
-
-	/* Read the Basic Flash Parameter Table. */
-	len = min_t(size_t, sizeof(bfpt),
-		    bfpt_header->length * sizeof(u32));
-	addr = SFDP_PARAM_HEADER_PTP(bfpt_header);
-	memset(&bfpt, 0, sizeof(bfpt));
-	err = spi_nor_read_sfdp_dma_unsafe(nor,  addr, len, &bfpt);
-	if (err < 0)
-		return err;
-
-	/* Fix endianness of the BFPT DWORDs. */
-	for (i = 0; i < BFPT_DWORD_MAX; i++)
-		bfpt.dwords[i] = le32_to_cpu(bfpt.dwords[i]);
-
-	/* Number of address bytes. */
-	switch (bfpt.dwords[BFPT_DWORD(1)] & BFPT_DWORD1_ADDRESS_BYTES_MASK) {
-	case BFPT_DWORD1_ADDRESS_BYTES_3_ONLY:
-		nor->addr_width = 3;
-		break;
-
-	case BFPT_DWORD1_ADDRESS_BYTES_4_ONLY:
-		nor->addr_width = 4;
-		break;
-
-	default:
-		break;
-	}
-
-	/* Flash Memory Density (in bits). */
-	params->size = bfpt.dwords[BFPT_DWORD(2)];
-	if (params->size & BIT(31)) {
-		params->size &= ~BIT(31);
-
-		/*
-		 * Prevent overflows on params->size. Anyway, a NOR of 2^64
-		 * bits is unlikely to exist so this error probably means
-		 * the BFPT we are reading is corrupted/wrong.
-		 */
-		if (params->size > 63)
-			return -EINVAL;
-
-		params->size = 1ULL << params->size;
-	} else {
-		params->size++;
-	}
-	params->size >>= 3; /* Convert to bytes. */
-
-	/* Fast Read settings. */
-	for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_reads); i++) {
-		const struct sfdp_bfpt_read *rd = &sfdp_bfpt_reads[i];
-		struct spi_nor_read_command *read;
-
-		if (!(bfpt.dwords[rd->supported_dword] & rd->supported_bit)) {
-			params->hwcaps.mask &= ~rd->hwcaps;
-			continue;
-		}
-
-		params->hwcaps.mask |= rd->hwcaps;
-		cmd = spi_nor_hwcaps_read2cmd(rd->hwcaps);
-		read = &params->reads[cmd];
-		half = bfpt.dwords[rd->settings_dword] >> rd->settings_shift;
-		spi_nor_set_read_settings_from_bfpt(read, half, rd->proto);
-	}
-
-	/*
-	 * Sector Erase settings. Reinitialize the uniform erase map using the
-	 * Erase Types defined in the bfpt table.
-	 */
-	erase_mask = 0;
-	memset(&nor->erase_map, 0, sizeof(nor->erase_map));
-	for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_erases); i++) {
-		const struct sfdp_bfpt_erase *er = &sfdp_bfpt_erases[i];
-		u32 erasesize;
-		u8 opcode;
-
-		half = bfpt.dwords[er->dword] >> er->shift;
-		erasesize = half & 0xff;
-
-		/* erasesize == 0 means this Erase Type is not supported. */
-		if (!erasesize)
-			continue;
-
-		erasesize = 1U << erasesize;
-		opcode = (half >> 8) & 0xff;
-		erase_mask |= BIT(i);
-		spi_nor_set_erase_settings_from_bfpt(&erase_type[i], erasesize,
-						     opcode, i);
-	}
-	spi_nor_init_uniform_erase_map(map, erase_mask, params->size);
-	/*
-	 * Sort all the map's Erase Types in ascending order with the smallest
-	 * erase size being the first member in the erase_type array.
-	 */
-	sort(erase_type, SNOR_ERASE_TYPE_MAX, sizeof(erase_type[0]),
-	     spi_nor_map_cmp_erase_type, NULL);
-	/*
-	 * Sort the erase types in the uniform region in order to update the
-	 * uniform_erase_type bitmask. The bitmask will be used later on when
-	 * selecting the uniform erase.
-	 */
-	spi_nor_regions_sort_erase_types(map);
-	map->uniform_erase_type = map->uniform_region.offset &
-				  SNOR_ERASE_TYPE_MASK;
-
-	/* Stop here if not JESD216 rev A or later. */
-	if (bfpt_header->length < BFPT_DWORD_MAX)
-		return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt,
-						params);
-
-	/* Page size: this field specifies 'N' so the page size = 2^N bytes. */
-	params->page_size = bfpt.dwords[BFPT_DWORD(11)];
-	params->page_size &= BFPT_DWORD11_PAGE_SIZE_MASK;
-	params->page_size >>= BFPT_DWORD11_PAGE_SIZE_SHIFT;
-	params->page_size = 1U << params->page_size;
-
-	/* Quad Enable Requirements. */
-	switch (bfpt.dwords[BFPT_DWORD(15)] & BFPT_DWORD15_QER_MASK) {
-	case BFPT_DWORD15_QER_NONE:
-		params->quad_enable = no_quad_enable;
-		break;
-
-	case BFPT_DWORD15_QER_SR2_BIT1_BUGGY:
-	case BFPT_DWORD15_QER_SR2_BIT1_NO_RD:
-		params->quad_enable = sr2_bit1_no_read_quad_enable;
-		break;
-
-	case BFPT_DWORD15_QER_SR1_BIT6:
-		params->quad_enable = sr1_bit6_quad_enable;
-		break;
-
-	case BFPT_DWORD15_QER_SR2_BIT7:
-		params->quad_enable = sr2_bit7_quad_enable;
-		break;
-
-	case BFPT_DWORD15_QER_SR2_BIT1:
-		params->quad_enable = sr2_bit1_read_quad_enable;
-		break;
-
-	default:
-		return -EINVAL;
-	}
-
-	return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt, params);
-}
-
-#define SMPT_CMD_ADDRESS_LEN_MASK		GENMASK(23, 22)
-#define SMPT_CMD_ADDRESS_LEN_0			(0x0UL << 22)
-#define SMPT_CMD_ADDRESS_LEN_3			(0x1UL << 22)
-#define SMPT_CMD_ADDRESS_LEN_4			(0x2UL << 22)
-#define SMPT_CMD_ADDRESS_LEN_USE_CURRENT	(0x3UL << 22)
-
-#define SMPT_CMD_READ_DUMMY_MASK		GENMASK(19, 16)
-#define SMPT_CMD_READ_DUMMY_SHIFT		16
-#define SMPT_CMD_READ_DUMMY(_cmd) \
-	(((_cmd) & SMPT_CMD_READ_DUMMY_MASK) >> SMPT_CMD_READ_DUMMY_SHIFT)
-#define SMPT_CMD_READ_DUMMY_IS_VARIABLE		0xfUL
-
-#define SMPT_CMD_READ_DATA_MASK			GENMASK(31, 24)
-#define SMPT_CMD_READ_DATA_SHIFT		24
-#define SMPT_CMD_READ_DATA(_cmd) \
-	(((_cmd) & SMPT_CMD_READ_DATA_MASK) >> SMPT_CMD_READ_DATA_SHIFT)
-
-#define SMPT_CMD_OPCODE_MASK			GENMASK(15, 8)
-#define SMPT_CMD_OPCODE_SHIFT			8
-#define SMPT_CMD_OPCODE(_cmd) \
-	(((_cmd) & SMPT_CMD_OPCODE_MASK) >> SMPT_CMD_OPCODE_SHIFT)
-
-#define SMPT_MAP_REGION_COUNT_MASK		GENMASK(23, 16)
-#define SMPT_MAP_REGION_COUNT_SHIFT		16
-#define SMPT_MAP_REGION_COUNT(_header) \
-	((((_header) & SMPT_MAP_REGION_COUNT_MASK) >> \
-	  SMPT_MAP_REGION_COUNT_SHIFT) + 1)
-
-#define SMPT_MAP_ID_MASK			GENMASK(15, 8)
-#define SMPT_MAP_ID_SHIFT			8
-#define SMPT_MAP_ID(_header) \
-	(((_header) & SMPT_MAP_ID_MASK) >> SMPT_MAP_ID_SHIFT)
-
-#define SMPT_MAP_REGION_SIZE_MASK		GENMASK(31, 8)
-#define SMPT_MAP_REGION_SIZE_SHIFT		8
-#define SMPT_MAP_REGION_SIZE(_region) \
-	(((((_region) & SMPT_MAP_REGION_SIZE_MASK) >> \
-	   SMPT_MAP_REGION_SIZE_SHIFT) + 1) * 256)
-
-#define SMPT_MAP_REGION_ERASE_TYPE_MASK		GENMASK(3, 0)
-#define SMPT_MAP_REGION_ERASE_TYPE(_region) \
-	((_region) & SMPT_MAP_REGION_ERASE_TYPE_MASK)
-
-#define SMPT_DESC_TYPE_MAP			BIT(1)
-#define SMPT_DESC_END				BIT(0)
-
-/**
- * spi_nor_smpt_addr_width() - return the address width used in the
- *			       configuration detection command.
- * @nor:	pointer to a 'struct spi_nor'
- * @settings:	configuration detection command descriptor, dword1
- */
-static u8 spi_nor_smpt_addr_width(const struct spi_nor *nor, const u32 settings)
-{
-	switch (settings & SMPT_CMD_ADDRESS_LEN_MASK) {
-	case SMPT_CMD_ADDRESS_LEN_0:
-		return 0;
-	case SMPT_CMD_ADDRESS_LEN_3:
-		return 3;
-	case SMPT_CMD_ADDRESS_LEN_4:
-		return 4;
-	case SMPT_CMD_ADDRESS_LEN_USE_CURRENT:
-		/* fall through */
-	default:
-		return nor->addr_width;
-	}
-}
-
-/**
- * spi_nor_smpt_read_dummy() - return the configuration detection command read
- *			       latency, in clock cycles.
- * @nor:	pointer to a 'struct spi_nor'
- * @settings:	configuration detection command descriptor, dword1
- *
- * Return: the number of dummy cycles for an SMPT read
- */
-static u8 spi_nor_smpt_read_dummy(const struct spi_nor *nor, const u32 settings)
-{
-	u8 read_dummy = SMPT_CMD_READ_DUMMY(settings);
-
-	if (read_dummy == SMPT_CMD_READ_DUMMY_IS_VARIABLE)
-		return nor->read_dummy;
-	return read_dummy;
-}
-
-/**
- * spi_nor_get_map_in_use() - get the configuration map in use
- * @nor:	pointer to a 'struct spi_nor'
- * @smpt:	pointer to the sector map parameter table
- */
-static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt)
-{
-	const u32 *ret = NULL;
-	u32 i, addr;
-	int err;
-	u8 addr_width, read_opcode, read_dummy;
-	u8 read_data_mask, data_byte, map_id;
-
-	addr_width = nor->addr_width;
-	read_dummy = nor->read_dummy;
-	read_opcode = nor->read_opcode;
-
-	map_id = 0;
-	i = 0;
-	/* Determine if there are any optional Detection Command Descriptors */
-	while (!(smpt[i] & SMPT_DESC_TYPE_MAP)) {
-		read_data_mask = SMPT_CMD_READ_DATA(smpt[i]);
-		nor->addr_width = spi_nor_smpt_addr_width(nor, smpt[i]);
-		nor->read_dummy = spi_nor_smpt_read_dummy(nor, smpt[i]);
-		nor->read_opcode = SMPT_CMD_OPCODE(smpt[i]);
-		addr = smpt[i + 1];
-
-		err = spi_nor_read_raw(nor, addr, 1, &data_byte);
-		if (err)
-			goto out;
-
-		/*
-		 * Build an index value that is used to select the Sector Map
-		 * Configuration that is currently in use.
-		 */
-		map_id = map_id << 1 | !!(data_byte & read_data_mask);
-		i = i + 2;
-	}
-
-	/* Find the matching configuration map */
-	while (SMPT_MAP_ID(smpt[i]) != map_id) {
-		if (smpt[i] & SMPT_DESC_END)
-			goto out;
-		/* increment the table index to the next map */
-		i += SMPT_MAP_REGION_COUNT(smpt[i]) + 1;
-	}
-
-	ret = smpt + i;
-	/* fall through */
-out:
-	nor->addr_width = addr_width;
-	nor->read_dummy = read_dummy;
-	nor->read_opcode = read_opcode;
-	return ret;
-}
-
-/**
- * spi_nor_region_check_overlay() - set overlay bit when the region is overlaid
- * @region:	pointer to a structure that describes a SPI NOR erase region
- * @erase:	pointer to a structure that describes a SPI NOR erase type
- * @erase_type:	erase type bitmask
- */
-static void
-spi_nor_region_check_overlay(struct spi_nor_erase_region *region,
-			     const struct spi_nor_erase_type *erase,
-			     const u8 erase_type)
-{
-	int i;
-
-	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
-		if (!(erase_type & BIT(i)))
-			continue;
-		if (region->size & erase[i].size_mask) {
-			spi_nor_region_mark_overlay(region);
-			return;
-		}
-	}
-}
-
-/**
- * spi_nor_init_non_uniform_erase_map() - initialize the non-uniform erase map
- * @nor:	pointer to a 'struct spi_nor'
- * @smpt:	pointer to the sector map parameter table
- *
- * Return: 0 on success, -errno otherwise.
- */
-static int spi_nor_init_non_uniform_erase_map(struct spi_nor *nor,
-					      const u32 *smpt)
-{
-	struct spi_nor_erase_map *map = &nor->erase_map;
-	const struct spi_nor_erase_type *erase = map->erase_type;
-	struct spi_nor_erase_region *region;
-	u64 offset;
-	u32 region_count;
-	int i, j;
-	u8 erase_type;
-
-	region_count = SMPT_MAP_REGION_COUNT(*smpt);
-	/*
-	 * The regions will be freed when the driver detaches from the
-	 * device.
-	 */
-	region = devm_kcalloc(nor->dev, region_count, sizeof(*region),
-			      GFP_KERNEL);
-	if (!region)
-		return -ENOMEM;
-	map->regions = region;
-
-	map->uniform_erase_type = 0xff;
-	offset = 0;
-	/* Populate regions. */
-	for (i = 0; i < region_count; i++) {
-		j = i + 1; /* index for the region dword */
-		region[i].size = SMPT_MAP_REGION_SIZE(smpt[j]);
-		erase_type = SMPT_MAP_REGION_ERASE_TYPE(smpt[j]);
-		region[i].offset = offset | erase_type;
-
-		spi_nor_region_check_overlay(&region[i], erase, erase_type);
-
-		/*
-		 * Save the erase types that are supported in all regions and
-		 * can erase the entire flash memory.
-		 */
-		map->uniform_erase_type &= erase_type;
-
-		offset = (region[i].offset & ~SNOR_ERASE_FLAGS_MASK) +
-			 region[i].size;
-	}
-
-	spi_nor_region_mark_end(&region[i - 1]);
-
-	return 0;
-}
-
-/**
- * spi_nor_parse_smpt() - parse Sector Map Parameter Table
- * @nor:		pointer to a 'struct spi_nor'
- * @smpt_header:	sector map parameter table header
- *
- * This table is optional, but when available, we parse it to identify the
- * location and size of sectors within the main data array of the flash memory
- * device and to identify which Erase Types are supported by each sector.
- *
- * Return: 0 on success, -errno otherwise.
- */
-static int spi_nor_parse_smpt(struct spi_nor *nor,
-			      const struct sfdp_parameter_header *smpt_header)
-{
-	const u32 *sector_map;
-	u32 *smpt;
-	size_t len;
-	u32 addr;
-	int i, ret;
-
-	/* Read the Sector Map Parameter Table. */
-	len = smpt_header->length * sizeof(*smpt);
-	smpt = kmalloc(len, GFP_KERNEL);
-	if (!smpt)
-		return -ENOMEM;
-
-	addr = SFDP_PARAM_HEADER_PTP(smpt_header);
-	ret = spi_nor_read_sfdp(nor, addr, len, smpt);
-	if (ret)
-		goto out;
-
-	/* Fix endianness of the SMPT DWORDs. */
-	for (i = 0; i < smpt_header->length; i++)
-		smpt[i] = le32_to_cpu(smpt[i]);
-
-	sector_map = spi_nor_get_map_in_use(nor, smpt);
-	if (!sector_map) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	ret = spi_nor_init_non_uniform_erase_map(nor, sector_map);
-	if (ret)
-		goto out;
-
-	spi_nor_regions_sort_erase_types(&nor->erase_map);
-	/* fall through */
-out:
-	kfree(smpt);
-	return ret;
-}
-
-/**
- * spi_nor_parse_sfdp() - parse the Serial Flash Discoverable Parameters.
- * @nor:		pointer to a 'struct spi_nor'
- * @params:		pointer to the 'struct spi_nor_flash_parameter' to be
- *			filled
- *
- * The Serial Flash Discoverable Parameters are described by the JEDEC JESD216
- * specification. This is a standard which tends to supported by almost all
- * (Q)SPI memory manufacturers. Those hard-coded tables allow us to learn at
- * runtime the main parameters needed to perform basic SPI flash operations such
- * as Fast Read, Page Program or Sector Erase commands.
- *
- * Return: 0 on success, -errno otherwise.
- */
-static int spi_nor_parse_sfdp(struct spi_nor *nor,
-			      struct spi_nor_flash_parameter *params)
-{
-	const struct sfdp_parameter_header *param_header, *bfpt_header;
-	struct sfdp_parameter_header *param_headers = NULL;
-	struct sfdp_header header;
-	struct device *dev = nor->dev;
-	size_t psize;
-	int i, err;
-
-	/* Get the SFDP header. */
-	err = spi_nor_read_sfdp_dma_unsafe(nor, 0, sizeof(header), &header);
-	if (err < 0)
-		return err;
-
-	/* Check the SFDP header version. */
-	if (le32_to_cpu(header.signature) != SFDP_SIGNATURE ||
-	    header.major != SFDP_JESD216_MAJOR)
-		return -EINVAL;
-
-	/*
-	 * Verify that the first and only mandatory parameter header is a
-	 * Basic Flash Parameter Table header as specified in JESD216.
-	 */
-	bfpt_header = &header.bfpt_header;
-	if (SFDP_PARAM_HEADER_ID(bfpt_header) != SFDP_BFPT_ID ||
-	    bfpt_header->major != SFDP_JESD216_MAJOR)
-		return -EINVAL;
-
-	/*
-	 * Allocate memory then read all parameter headers with a single
-	 * Read SFDP command. These parameter headers will actually be parsed
-	 * twice: a first time to get the latest revision of the basic flash
-	 * parameter table, then a second time to handle the supported optional
-	 * tables.
-	 * Hence we read the parameter headers once for all to reduce the
-	 * processing time. Also we use kmalloc() instead of devm_kmalloc()
-	 * because we don't need to keep these parameter headers: the allocated
-	 * memory is always released with kfree() before exiting this function.
-	 */
-	if (header.nph) {
-		psize = header.nph * sizeof(*param_headers);
-
-		param_headers = kmalloc(psize, GFP_KERNEL);
-		if (!param_headers)
-			return -ENOMEM;
-
-		err = spi_nor_read_sfdp(nor, sizeof(header),
-					psize, param_headers);
-		if (err < 0) {
-			dev_err(dev, "failed to read SFDP parameter headers\n");
-			goto exit;
-		}
-	}
-
-	/*
-	 * Check other parameter headers to get the latest revision of
-	 * the basic flash parameter table.
-	 */
-	for (i = 0; i < header.nph; i++) {
-		param_header = &param_headers[i];
-
-		if (SFDP_PARAM_HEADER_ID(param_header) == SFDP_BFPT_ID &&
-		    param_header->major == SFDP_JESD216_MAJOR &&
-		    (param_header->minor > bfpt_header->minor ||
-		     (param_header->minor == bfpt_header->minor &&
-		      param_header->length > bfpt_header->length)))
-			bfpt_header = param_header;
-	}
-
-	err = spi_nor_parse_bfpt(nor, bfpt_header, params);
-	if (err)
-		goto exit;
-
-	/* Parse other parameter headers. */
-	for (i = 0; i < header.nph; i++) {
-		param_header = &param_headers[i];
-
-		switch (SFDP_PARAM_HEADER_ID(param_header)) {
-		case SFDP_SECTOR_MAP_ID:
-			err = spi_nor_parse_smpt(nor, param_header);
-			break;
-
-		default:
-			break;
-		}
-
-		if (err)
-			goto exit;
-	}
-
-exit:
-	kfree(param_headers);
-	return err;
-}
-
 static int spi_nor_init_params(struct spi_nor *nor,
 			       struct spi_nor_flash_parameter *params)
 {
diff --git a/drivers/mtd/spi-nor/internals.h b/drivers/mtd/spi-nor/internals.h
index 96b08b53f8f6..ae3eb40d7241 100644
--- a/drivers/mtd/spi-nor/internals.h
+++ b/drivers/mtd/spi-nor/internals.h
@@ -345,16 +345,31 @@ extern const struct spi_nor_manufacturer spi_nor_xmc;
 int en4_ex4_set_4byte(struct spi_nor *nor, bool enable);
 int en4_ex4_wen_set_4byte(struct spi_nor *nor, bool enable);
 int sr1_bit6_quad_enable(struct spi_nor *nor);
+int sr2_bit7_quad_enable(struct spi_nor *nor);
+int sr2_bit1_read_quad_enable(struct spi_nor *nor);
+int sr2_bit1_no_read_quad_enable(struct spi_nor *nor);
 int no_quad_enable(struct spi_nor *nor);
 int write_enable(struct spi_nor *nor);
 int write_disable(struct spi_nor *nor);
 int spi_nor_lock_and_prep(struct spi_nor *nor, enum spi_nor_ops ops);
 void spi_nor_unlock_and_unprep(struct spi_nor *nor, enum spi_nor_ops ops);
 int spi_nor_wait_till_ready(struct spi_nor *nor);
+void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
+                                    u8 erase_mask, u64 flash_size);
+void spi_nor_set_erase_type(struct spi_nor_erase_type *erase, u32 size,
+                            u8 opcode);
+struct spi_nor_erase_region *
+spi_nor_region_next(struct spi_nor_erase_region *region);
+int spi_nor_read_raw(struct spi_nor *nor, u32 addr, size_t len, u8 *buf);
+int spi_nor_hwcaps_read2cmd(u32 hwcaps);
 
 static inline struct spi_nor *mtd_to_spi_nor(struct mtd_info *mtd)
 {
 	return mtd->priv;
 }
 
+/* SFDP functions. */
+int spi_nor_parse_sfdp(struct spi_nor *nor,
+		       struct spi_nor_flash_parameter *params);
+
 #endif /* __LINUX_MTD_SPI_NOR_INTERNALS_H */
diff --git a/drivers/mtd/spi-nor/sfdp.c b/drivers/mtd/spi-nor/sfdp.c
new file mode 100644
index 000000000000..36343e3e6be0
--- /dev/null
+++ b/drivers/mtd/spi-nor/sfdp.c
@@ -0,0 +1,859 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2005, Intec Automation Inc.
+ * Copyright (C) 2014, Freescale Semiconductor, Inc.
+ */
+
+#include <linux/wait.h>
+#include <linux/mtd/spi-nor.h>
+#include <linux/slab.h>
+#include <linux/sort.h>
+
+#include "internals.h"
+
+/**
+ * spi_nor_read_sfdp() - read Serial Flash Discoverable Parameters.
+ * @nor:	pointer to a 'struct spi_nor'
+ * @addr:	offset in the SFDP area to start reading data from
+ * @len:	number of bytes to read
+ * @buf:	buffer where the SFDP data are copied into (dma-safe memory)
+ *
+ * Whatever the actual numbers of bytes for address and dummy cycles are
+ * for (Fast) Read commands, the Read SFDP (5Ah) instruction is always
+ * followed by a 3-byte address and 8 dummy clock cycles.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int spi_nor_read_sfdp(struct spi_nor *nor, u32 addr,
+			     size_t len, void *buf)
+{
+	u8 addr_width, read_opcode, read_dummy;
+	int ret;
+
+	read_opcode = nor->read_opcode;
+	addr_width = nor->addr_width;
+	read_dummy = nor->read_dummy;
+
+	nor->read_opcode = SPINOR_OP_RDSFDP;
+	nor->addr_width = 3;
+	nor->read_dummy = 8;
+
+	ret = spi_nor_read_raw(nor, addr, len, buf);
+
+	nor->read_opcode = read_opcode;
+	nor->addr_width = addr_width;
+	nor->read_dummy = read_dummy;
+
+	return ret;
+}
+
+/**
+ * spi_nor_read_sfdp_dma_unsafe() - read Serial Flash Discoverable Parameters.
+ * @nor:	pointer to a 'struct spi_nor'
+ * @addr:	offset in the SFDP area to start reading data from
+ * @len:	number of bytes to read
+ * @buf:	buffer where the SFDP data are copied into
+ *
+ * Wrap spi_nor_read_sfdp() using a kmalloc'ed bounce buffer as @buf is now not
+ * guaranteed to be dma-safe.
+ *
+ * Return: -ENOMEM if kmalloc() fails, the return code of spi_nor_read_sfdp()
+ *          otherwise.
+ */
+static int spi_nor_read_sfdp_dma_unsafe(struct spi_nor *nor, u32 addr,
+					size_t len, void *buf)
+{
+	void *dma_safe_buf;
+	int ret;
+
+	dma_safe_buf = kmalloc(len, GFP_KERNEL);
+	if (!dma_safe_buf)
+		return -ENOMEM;
+
+	ret = spi_nor_read_sfdp(nor, addr, len, dma_safe_buf);
+	memcpy(buf, dma_safe_buf, len);
+	kfree(dma_safe_buf);
+
+	return ret;
+}
+
+/**
+ * spi_nor_set_erase_settings_from_bfpt() - set erase type settings from BFPT
+ * @erase:	pointer to a structure that describes a SPI NOR erase type
+ * @size:	the size of the sector/block erased by the erase type
+ * @opcode:	the SPI command op code to erase the sector/block
+ * @i:		erase type index as sorted in the Basic Flash Parameter Table
+ *
+ * The supported Erase Types will be sorted at init in ascending order, with
+ * the smallest Erase Type size being the first member in the erase_type array
+ * of the spi_nor_erase_map structure. Save the Erase Type index as sorted in
+ * the Basic Flash Parameter Table since it will be used later on to
+ * synchronize with the supported Erase Types defined in SFDP optional tables.
+ */
+static void
+spi_nor_set_erase_settings_from_bfpt(struct spi_nor_erase_type *erase,
+				     u32 size, u8 opcode, u8 i)
+{
+	erase->idx = i;
+	spi_nor_set_erase_type(erase, size, opcode);
+}
+
+/**
+ * spi_nor_map_cmp_erase_type() - compare the map's erase types by size
+ * @l:	member in the left half of the map's erase_type array
+ * @r:	member in the right half of the map's erase_type array
+ *
+ * Comparison function used in the sort() call to sort in ascending order the
+ * map's erase types, the smallest erase type size being the first member in the
+ * sorted erase_type array.
+ *
+ * Return: the result of @l->size - @r->size
+ */
+static int spi_nor_map_cmp_erase_type(const void *l, const void *r)
+{
+	const struct spi_nor_erase_type *left = l, *right = r;
+
+	return left->size - right->size;
+}
+
+/**
+ * spi_nor_regions_sort_erase_types() - sort erase types in each region
+ * @map:	the erase map of the SPI NOR
+ *
+ * Function assumes that the erase types defined in the erase map are already
+ * sorted in ascending order, with the smallest erase type size being the first
+ * member in the erase_type array. It replicates the sort done for the map's
+ * erase types. Each region's erase bitmask will indicate which erase types are
+ * supported from the sorted erase types defined in the erase map.
+ * Sort the all region's erase type at init in order to speed up the process of
+ * finding the best erase command at runtime.
+ */
+static void spi_nor_regions_sort_erase_types(struct spi_nor_erase_map *map)
+{
+	struct spi_nor_erase_region *region = map->regions;
+	struct spi_nor_erase_type *erase_type = map->erase_type;
+	int i;
+	u8 region_erase_mask, sorted_erase_mask;
+
+	while (region) {
+		region_erase_mask = region->offset & SNOR_ERASE_TYPE_MASK;
+
+		/* Replicate the sort done for the map's erase types. */
+		sorted_erase_mask = 0;
+		for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++)
+			if (erase_type[i].size &&
+			    region_erase_mask & BIT(erase_type[i].idx))
+				sorted_erase_mask |= BIT(i);
+
+		/* Overwrite erase mask. */
+		region->offset = (region->offset & ~SNOR_ERASE_TYPE_MASK) |
+				 sorted_erase_mask;
+
+		region = spi_nor_region_next(region);
+	}
+}
+
+#define SMPT_CMD_ADDRESS_LEN_MASK		GENMASK(23, 22)
+#define SMPT_CMD_ADDRESS_LEN_0			(0x0UL << 22)
+#define SMPT_CMD_ADDRESS_LEN_3			(0x1UL << 22)
+#define SMPT_CMD_ADDRESS_LEN_4			(0x2UL << 22)
+#define SMPT_CMD_ADDRESS_LEN_USE_CURRENT	(0x3UL << 22)
+
+#define SMPT_CMD_READ_DUMMY_MASK		GENMASK(19, 16)
+#define SMPT_CMD_READ_DUMMY_SHIFT		16
+#define SMPT_CMD_READ_DUMMY(_cmd) \
+	(((_cmd) & SMPT_CMD_READ_DUMMY_MASK) >> SMPT_CMD_READ_DUMMY_SHIFT)
+#define SMPT_CMD_READ_DUMMY_IS_VARIABLE		0xfUL
+
+#define SMPT_CMD_READ_DATA_MASK			GENMASK(31, 24)
+#define SMPT_CMD_READ_DATA_SHIFT		24
+#define SMPT_CMD_READ_DATA(_cmd) \
+	(((_cmd) & SMPT_CMD_READ_DATA_MASK) >> SMPT_CMD_READ_DATA_SHIFT)
+
+#define SMPT_CMD_OPCODE_MASK			GENMASK(15, 8)
+#define SMPT_CMD_OPCODE_SHIFT			8
+#define SMPT_CMD_OPCODE(_cmd) \
+	(((_cmd) & SMPT_CMD_OPCODE_MASK) >> SMPT_CMD_OPCODE_SHIFT)
+
+#define SMPT_MAP_REGION_COUNT_MASK		GENMASK(23, 16)
+#define SMPT_MAP_REGION_COUNT_SHIFT		16
+#define SMPT_MAP_REGION_COUNT(_header) \
+	((((_header) & SMPT_MAP_REGION_COUNT_MASK) >> \
+	  SMPT_MAP_REGION_COUNT_SHIFT) + 1)
+
+#define SMPT_MAP_ID_MASK			GENMASK(15, 8)
+#define SMPT_MAP_ID_SHIFT			8
+#define SMPT_MAP_ID(_header) \
+	(((_header) & SMPT_MAP_ID_MASK) >> SMPT_MAP_ID_SHIFT)
+
+#define SMPT_MAP_REGION_SIZE_MASK		GENMASK(31, 8)
+#define SMPT_MAP_REGION_SIZE_SHIFT		8
+#define SMPT_MAP_REGION_SIZE(_region) \
+	(((((_region) & SMPT_MAP_REGION_SIZE_MASK) >> \
+	   SMPT_MAP_REGION_SIZE_SHIFT) + 1) * 256)
+
+#define SMPT_MAP_REGION_ERASE_TYPE_MASK		GENMASK(3, 0)
+#define SMPT_MAP_REGION_ERASE_TYPE(_region) \
+	((_region) & SMPT_MAP_REGION_ERASE_TYPE_MASK)
+
+#define SMPT_DESC_TYPE_MAP			BIT(1)
+#define SMPT_DESC_END				BIT(0)
+
+/**
+ * spi_nor_smpt_addr_width() - return the address width used in the
+ *			       configuration detection command.
+ * @nor:	pointer to a 'struct spi_nor'
+ * @settings:	configuration detection command descriptor, dword1
+ */
+static u8 spi_nor_smpt_addr_width(const struct spi_nor *nor, const u32 settings)
+{
+	switch (settings & SMPT_CMD_ADDRESS_LEN_MASK) {
+	case SMPT_CMD_ADDRESS_LEN_0:
+		return 0;
+	case SMPT_CMD_ADDRESS_LEN_3:
+		return 3;
+	case SMPT_CMD_ADDRESS_LEN_4:
+		return 4;
+	case SMPT_CMD_ADDRESS_LEN_USE_CURRENT:
+		/* fall through */
+	default:
+		return nor->addr_width;
+	}
+}
+
+/**
+ * spi_nor_smpt_read_dummy() - return the configuration detection command read
+ *			       latency, in clock cycles.
+ * @nor:	pointer to a 'struct spi_nor'
+ * @settings:	configuration detection command descriptor, dword1
+ *
+ * Return: the number of dummy cycles for an SMPT read
+ */
+static u8 spi_nor_smpt_read_dummy(const struct spi_nor *nor, const u32 settings)
+{
+	u8 read_dummy = SMPT_CMD_READ_DUMMY(settings);
+
+	if (read_dummy == SMPT_CMD_READ_DUMMY_IS_VARIABLE)
+		return nor->read_dummy;
+	return read_dummy;
+}
+
+/**
+ * spi_nor_get_map_in_use() - get the configuration map in use
+ * @nor:	pointer to a 'struct spi_nor'
+ * @smpt:	pointer to the sector map parameter table
+ */
+static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt)
+{
+	const u32 *ret = NULL;
+	u32 i, addr;
+	int err;
+	u8 addr_width, read_opcode, read_dummy;
+	u8 read_data_mask, data_byte, map_id;
+
+	addr_width = nor->addr_width;
+	read_dummy = nor->read_dummy;
+	read_opcode = nor->read_opcode;
+
+	map_id = 0;
+	i = 0;
+	/* Determine if there are any optional Detection Command Descriptors */
+	while (!(smpt[i] & SMPT_DESC_TYPE_MAP)) {
+		read_data_mask = SMPT_CMD_READ_DATA(smpt[i]);
+		nor->addr_width = spi_nor_smpt_addr_width(nor, smpt[i]);
+		nor->read_dummy = spi_nor_smpt_read_dummy(nor, smpt[i]);
+		nor->read_opcode = SMPT_CMD_OPCODE(smpt[i]);
+		addr = smpt[i + 1];
+
+		err = spi_nor_read_raw(nor, addr, 1, &data_byte);
+		if (err)
+			goto out;
+
+		/*
+		 * Build an index value that is used to select the Sector Map
+		 * Configuration that is currently in use.
+		 */
+		map_id = map_id << 1 | !!(data_byte & read_data_mask);
+		i = i + 2;
+	}
+
+	/* Find the matching configuration map */
+	while (SMPT_MAP_ID(smpt[i]) != map_id) {
+		if (smpt[i] & SMPT_DESC_END)
+			goto out;
+		/* increment the table index to the next map */
+		i += SMPT_MAP_REGION_COUNT(smpt[i]) + 1;
+	}
+
+	ret = smpt + i;
+	/* fall through */
+out:
+	nor->addr_width = addr_width;
+	nor->read_dummy = read_dummy;
+	nor->read_opcode = read_opcode;
+	return ret;
+}
+
+/**
+ * spi_nor_region_check_overlay() - set overlay bit when the region is overlaid
+ * @region:	pointer to a structure that describes a SPI NOR erase region
+ * @erase:	pointer to a structure that describes a SPI NOR erase type
+ * @erase_type:	erase type bitmask
+ */
+static void
+spi_nor_region_check_overlay(struct spi_nor_erase_region *region,
+			     const struct spi_nor_erase_type *erase,
+			     const u8 erase_type)
+{
+	int i;
+
+	for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
+		if (!(erase_type & BIT(i)))
+			continue;
+		if (region->size & erase[i].size_mask) {
+			spi_nor_region_mark_overlay(region);
+			return;
+		}
+	}
+}
+
+/**
+ * spi_nor_init_non_uniform_erase_map() - initialize the non-uniform erase map
+ * @nor:	pointer to a 'struct spi_nor'
+ * @smpt:	pointer to the sector map parameter table
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int spi_nor_init_non_uniform_erase_map(struct spi_nor *nor,
+					      const u32 *smpt)
+{
+	struct spi_nor_erase_map *map = &nor->erase_map;
+	const struct spi_nor_erase_type *erase = map->erase_type;
+	struct spi_nor_erase_region *region;
+	u64 offset;
+	u32 region_count;
+	int i, j;
+	u8 erase_type;
+
+	region_count = SMPT_MAP_REGION_COUNT(*smpt);
+	/*
+	 * The regions will be freed when the driver detaches from the
+	 * device.
+	 */
+	region = devm_kcalloc(nor->dev, region_count, sizeof(*region),
+			      GFP_KERNEL);
+	if (!region)
+		return -ENOMEM;
+	map->regions = region;
+
+	map->uniform_erase_type = 0xff;
+	offset = 0;
+	/* Populate regions. */
+	for (i = 0; i < region_count; i++) {
+		j = i + 1; /* index for the region dword */
+		region[i].size = SMPT_MAP_REGION_SIZE(smpt[j]);
+		erase_type = SMPT_MAP_REGION_ERASE_TYPE(smpt[j]);
+		region[i].offset = offset | erase_type;
+
+		spi_nor_region_check_overlay(&region[i], erase, erase_type);
+
+		/*
+		 * Save the erase types that are supported in all regions and
+		 * can erase the entire flash memory.
+		 */
+		map->uniform_erase_type &= erase_type;
+
+		offset = (region[i].offset & ~SNOR_ERASE_FLAGS_MASK) +
+			 region[i].size;
+	}
+
+	spi_nor_region_mark_end(&region[i - 1]);
+
+	return 0;
+}
+
+/**
+ * spi_nor_parse_smpt() - parse Sector Map Parameter Table
+ * @nor:		pointer to a 'struct spi_nor'
+ * @smpt_header:	sector map parameter table header
+ *
+ * This table is optional, but when available, we parse it to identify the
+ * location and size of sectors within the main data array of the flash memory
+ * device and to identify which Erase Types are supported by each sector.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int spi_nor_parse_smpt(struct spi_nor *nor,
+			      const struct sfdp_parameter_header *smpt_header)
+{
+	const u32 *sector_map;
+	u32 *smpt;
+	size_t len;
+	u32 addr;
+	int i, ret;
+
+	/* Read the Sector Map Parameter Table. */
+	len = smpt_header->length * sizeof(*smpt);
+	smpt = kmalloc(len, GFP_KERNEL);
+	if (!smpt)
+		return -ENOMEM;
+
+	addr = SFDP_PARAM_HEADER_PTP(smpt_header);
+	ret = spi_nor_read_sfdp(nor, addr, len, smpt);
+	if (ret)
+		goto out;
+
+	/* Fix endianness of the SMPT DWORDs. */
+	for (i = 0; i < smpt_header->length; i++)
+		smpt[i] = le32_to_cpu(smpt[i]);
+
+	sector_map = spi_nor_get_map_in_use(nor, smpt);
+	if (!sector_map) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = spi_nor_init_non_uniform_erase_map(nor, sector_map);
+	if (ret)
+		goto out;
+
+	spi_nor_regions_sort_erase_types(&nor->erase_map);
+	/* fall through */
+out:
+	kfree(smpt);
+	return ret;
+}
+
+static void
+spi_nor_set_read_settings_from_bfpt(struct spi_nor_read_command *read,
+				    u16 half,
+				    enum spi_nor_protocol proto)
+{
+	read->num_mode_clocks = (half >> 5) & 0x07;
+	read->num_wait_states = (half >> 0) & 0x1f;
+	read->opcode = (half >> 8) & 0xff;
+	read->proto = proto;
+}
+
+struct sfdp_bfpt_read {
+	/* The Fast Read x-y-z hardware capability in params->hwcaps.mask. */
+	u32			hwcaps;
+
+	/*
+	 * The <supported_bit> bit in <supported_dword> BFPT DWORD tells us
+	 * whether the Fast Read x-y-z command is supported.
+	 */
+	u32			supported_dword;
+	u32			supported_bit;
+
+	/*
+	 * The half-word at offset <setting_shift> in <setting_dword> BFPT DWORD
+	 * encodes the op code, the number of mode clocks and the number of wait
+	 * states to be used by Fast Read x-y-z command.
+	 */
+	u32			settings_dword;
+	u32			settings_shift;
+
+	/* The SPI protocol for this Fast Read x-y-z command. */
+	enum spi_nor_protocol	proto;
+};
+
+static const struct sfdp_bfpt_read sfdp_bfpt_reads[] = {
+	/* Fast Read 1-1-2 */
+	{
+		SNOR_HWCAPS_READ_1_1_2,
+		BFPT_DWORD(1), BIT(16),	/* Supported bit */
+		BFPT_DWORD(4), 0,	/* Settings */
+		SNOR_PROTO_1_1_2,
+	},
+
+	/* Fast Read 1-2-2 */
+	{
+		SNOR_HWCAPS_READ_1_2_2,
+		BFPT_DWORD(1), BIT(20),	/* Supported bit */
+		BFPT_DWORD(4), 16,	/* Settings */
+		SNOR_PROTO_1_2_2,
+	},
+
+	/* Fast Read 2-2-2 */
+	{
+		SNOR_HWCAPS_READ_2_2_2,
+		BFPT_DWORD(5),  BIT(0),	/* Supported bit */
+		BFPT_DWORD(6), 16,	/* Settings */
+		SNOR_PROTO_2_2_2,
+	},
+
+	/* Fast Read 1-1-4 */
+	{
+		SNOR_HWCAPS_READ_1_1_4,
+		BFPT_DWORD(1), BIT(22),	/* Supported bit */
+		BFPT_DWORD(3), 16,	/* Settings */
+		SNOR_PROTO_1_1_4,
+	},
+
+	/* Fast Read 1-4-4 */
+	{
+		SNOR_HWCAPS_READ_1_4_4,
+		BFPT_DWORD(1), BIT(21),	/* Supported bit */
+		BFPT_DWORD(3), 0,	/* Settings */
+		SNOR_PROTO_1_4_4,
+	},
+
+	/* Fast Read 4-4-4 */
+	{
+		SNOR_HWCAPS_READ_4_4_4,
+		BFPT_DWORD(5), BIT(4),	/* Supported bit */
+		BFPT_DWORD(7), 16,	/* Settings */
+		SNOR_PROTO_4_4_4,
+	},
+};
+
+struct sfdp_bfpt_erase {
+	/*
+	 * The half-word at offset <shift> in DWORD <dwoard> encodes the
+	 * op code and erase sector size to be used by Sector Erase commands.
+	 */
+	u32			dword;
+	u32			shift;
+};
+
+static const struct sfdp_bfpt_erase sfdp_bfpt_erases[] = {
+	/* Erase Type 1 in DWORD8 bits[15:0] */
+	{BFPT_DWORD(8), 0},
+
+	/* Erase Type 2 in DWORD8 bits[31:16] */
+	{BFPT_DWORD(8), 16},
+
+	/* Erase Type 3 in DWORD9 bits[15:0] */
+	{BFPT_DWORD(9), 0},
+
+	/* Erase Type 4 in DWORD9 bits[31:16] */
+	{BFPT_DWORD(9), 16},
+};
+
+static int
+spi_nor_post_bfpt_fixups(struct spi_nor *nor,
+			 const struct sfdp_parameter_header *bfpt_header,
+			 const struct sfdp_bfpt *bfpt,
+			 struct spi_nor_flash_parameter *params)
+{
+	int ret;
+
+	if (nor->manufacturer && nor->manufacturer->fixups &&
+	    nor->manufacturer->fixups->post_bfpt) {
+		ret = nor->manufacturer->fixups->post_bfpt(nor, bfpt_header,
+							   bfpt, params);
+		if (ret)
+			return ret;
+	}
+
+	if (nor->info->fixups && nor->info->fixups->post_bfpt) {
+		ret = nor->info->fixups->post_bfpt(nor, bfpt_header, bfpt,
+						   params);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * spi_nor_parse_bfpt() - read and parse the Basic Flash Parameter Table.
+ * @nor:		pointer to a 'struct spi_nor'
+ * @bfpt_header:	pointer to the 'struct sfdp_parameter_header' describing
+ *			the Basic Flash Parameter Table length and version
+ * @params:		pointer to the 'struct spi_nor_flash_parameter' to be
+ *			filled
+ *
+ * The Basic Flash Parameter Table is the main and only mandatory table as
+ * defined by the SFDP (JESD216) specification.
+ * It provides us with the total size (memory density) of the data array and
+ * the number of address bytes for Fast Read, Page Program and Sector Erase
+ * commands.
+ * For Fast READ commands, it also gives the number of mode clock cycles and
+ * wait states (regrouped in the number of dummy clock cycles) for each
+ * supported instruction op code.
+ * For Page Program, the page size is now available since JESD216 rev A, however
+ * the supported instruction op codes are still not provided.
+ * For Sector Erase commands, this table stores the supported instruction op
+ * codes and the associated sector sizes.
+ * Finally, the Quad Enable Requirements (QER) are also available since JESD216
+ * rev A. The QER bits encode the manufacturer dependent procedure to be
+ * executed to set the Quad Enable (QE) bit in some internal register of the
+ * Quad SPI memory. Indeed the QE bit, when it exists, must be set before
+ * sending any Quad SPI command to the memory. Actually, setting the QE bit
+ * tells the memory to reassign its WP# and HOLD#/RESET# pins to functions IO2
+ * and IO3 hence enabling 4 (Quad) I/O lines.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int spi_nor_parse_bfpt(struct spi_nor *nor,
+			      const struct sfdp_parameter_header *bfpt_header,
+			      struct spi_nor_flash_parameter *params)
+{
+	struct spi_nor_erase_map *map = &nor->erase_map;
+	struct spi_nor_erase_type *erase_type = map->erase_type;
+	struct sfdp_bfpt bfpt;
+	size_t len;
+	int i, cmd, err;
+	u32 addr;
+	u16 half;
+	u8 erase_mask;
+
+	/* JESD216 Basic Flash Parameter Table length is at least 9 DWORDs. */
+	if (bfpt_header->length < BFPT_DWORD_MAX_JESD216)
+		return -EINVAL;
+
+	/* Read the Basic Flash Parameter Table. */
+	len = min_t(size_t, sizeof(bfpt),
+		    bfpt_header->length * sizeof(u32));
+	addr = SFDP_PARAM_HEADER_PTP(bfpt_header);
+	memset(&bfpt, 0, sizeof(bfpt));
+	err = spi_nor_read_sfdp_dma_unsafe(nor,  addr, len, &bfpt);
+	if (err < 0)
+		return err;
+
+	/* Fix endianness of the BFPT DWORDs. */
+	for (i = 0; i < BFPT_DWORD_MAX; i++)
+		bfpt.dwords[i] = le32_to_cpu(bfpt.dwords[i]);
+
+	/* Number of address bytes. */
+	switch (bfpt.dwords[BFPT_DWORD(1)] & BFPT_DWORD1_ADDRESS_BYTES_MASK) {
+	case BFPT_DWORD1_ADDRESS_BYTES_3_ONLY:
+		nor->addr_width = 3;
+		break;
+
+	case BFPT_DWORD1_ADDRESS_BYTES_4_ONLY:
+		nor->addr_width = 4;
+		break;
+
+	default:
+		break;
+	}
+
+	/* Flash Memory Density (in bits). */
+	params->size = bfpt.dwords[BFPT_DWORD(2)];
+	if (params->size & BIT(31)) {
+		params->size &= ~BIT(31);
+
+		/*
+		 * Prevent overflows on params->size. Anyway, a NOR of 2^64
+		 * bits is unlikely to exist so this error probably means
+		 * the BFPT we are reading is corrupted/wrong.
+		 */
+		if (params->size > 63)
+			return -EINVAL;
+
+		params->size = 1ULL << params->size;
+	} else {
+		params->size++;
+	}
+	params->size >>= 3; /* Convert to bytes. */
+
+	/* Fast Read settings. */
+	for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_reads); i++) {
+		const struct sfdp_bfpt_read *rd = &sfdp_bfpt_reads[i];
+		struct spi_nor_read_command *read;
+
+		if (!(bfpt.dwords[rd->supported_dword] & rd->supported_bit)) {
+			params->hwcaps.mask &= ~rd->hwcaps;
+			continue;
+		}
+
+		params->hwcaps.mask |= rd->hwcaps;
+		cmd = spi_nor_hwcaps_read2cmd(rd->hwcaps);
+		read = &params->reads[cmd];
+		half = bfpt.dwords[rd->settings_dword] >> rd->settings_shift;
+		spi_nor_set_read_settings_from_bfpt(read, half, rd->proto);
+	}
+
+	/*
+	 * Sector Erase settings. Reinitialize the uniform erase map using the
+	 * Erase Types defined in the bfpt table.
+	 */
+	erase_mask = 0;
+	memset(&nor->erase_map, 0, sizeof(nor->erase_map));
+	for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_erases); i++) {
+		const struct sfdp_bfpt_erase *er = &sfdp_bfpt_erases[i];
+		u32 erasesize;
+		u8 opcode;
+
+		half = bfpt.dwords[er->dword] >> er->shift;
+		erasesize = half & 0xff;
+
+		/* erasesize == 0 means this Erase Type is not supported. */
+		if (!erasesize)
+			continue;
+
+		erasesize = 1U << erasesize;
+		opcode = (half >> 8) & 0xff;
+		erase_mask |= BIT(i);
+		spi_nor_set_erase_settings_from_bfpt(&erase_type[i], erasesize,
+						     opcode, i);
+	}
+	spi_nor_init_uniform_erase_map(map, erase_mask, params->size);
+	/*
+	 * Sort all the map's Erase Types in ascending order with the smallest
+	 * erase size being the first member in the erase_type array.
+	 */
+	sort(erase_type, SNOR_ERASE_TYPE_MAX, sizeof(erase_type[0]),
+	     spi_nor_map_cmp_erase_type, NULL);
+	/*
+	 * Sort the erase types in the uniform region in order to update the
+	 * uniform_erase_type bitmask. The bitmask will be used later on when
+	 * selecting the uniform erase.
+	 */
+	spi_nor_regions_sort_erase_types(map);
+	map->uniform_erase_type = map->uniform_region.offset &
+				  SNOR_ERASE_TYPE_MASK;
+
+	/* Stop here if not JESD216 rev A or later. */
+	if (bfpt_header->length < BFPT_DWORD_MAX)
+		return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt,
+						params);
+
+	/* Page size: this field specifies 'N' so the page size = 2^N bytes. */
+	params->page_size = bfpt.dwords[BFPT_DWORD(11)];
+	params->page_size &= BFPT_DWORD11_PAGE_SIZE_MASK;
+	params->page_size >>= BFPT_DWORD11_PAGE_SIZE_SHIFT;
+	params->page_size = 1U << params->page_size;
+
+	/* Quad Enable Requirements. */
+	switch (bfpt.dwords[BFPT_DWORD(15)] & BFPT_DWORD15_QER_MASK) {
+	case BFPT_DWORD15_QER_NONE:
+		params->quad_enable = no_quad_enable;
+		break;
+
+	case BFPT_DWORD15_QER_SR2_BIT1_BUGGY:
+	case BFPT_DWORD15_QER_SR2_BIT1_NO_RD:
+		params->quad_enable = sr2_bit1_no_read_quad_enable;
+		break;
+
+	case BFPT_DWORD15_QER_SR1_BIT6:
+		params->quad_enable = sr1_bit6_quad_enable;
+		break;
+
+	case BFPT_DWORD15_QER_SR2_BIT7:
+		params->quad_enable = sr2_bit7_quad_enable;
+		break;
+
+	case BFPT_DWORD15_QER_SR2_BIT1:
+		params->quad_enable = sr2_bit1_read_quad_enable;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt, params);
+}
+
+/**
+ * spi_nor_parse_sfdp() - parse the Serial Flash Discoverable Parameters.
+ * @nor:		pointer to a 'struct spi_nor'
+ * @params:		pointer to the 'struct spi_nor_flash_parameter' to be
+ *			filled
+ *
+ * The Serial Flash Discoverable Parameters are described by the JEDEC JESD216
+ * specification. This is a standard which tends to supported by almost all
+ * (Q)SPI memory manufacturers. Those hard-coded tables allow us to learn at
+ * runtime the main parameters needed to perform basic SPI flash operations such
+ * as Fast Read, Page Program or Sector Erase commands.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+int spi_nor_parse_sfdp(struct spi_nor *nor,
+		       struct spi_nor_flash_parameter *params)
+{
+	const struct sfdp_parameter_header *param_header, *bfpt_header;
+	struct sfdp_parameter_header *param_headers = NULL;
+	struct sfdp_header header;
+	struct device *dev = nor->dev;
+	size_t psize;
+	int i, err;
+
+	/* Get the SFDP header. */
+	err = spi_nor_read_sfdp_dma_unsafe(nor, 0, sizeof(header), &header);
+	if (err < 0)
+		return err;
+
+	/* Check the SFDP header version. */
+	if (le32_to_cpu(header.signature) != SFDP_SIGNATURE ||
+	    header.major != SFDP_JESD216_MAJOR)
+		return -EINVAL;
+
+	/*
+	 * Verify that the first and only mandatory parameter header is a
+	 * Basic Flash Parameter Table header as specified in JESD216.
+	 */
+	bfpt_header = &header.bfpt_header;
+	if (SFDP_PARAM_HEADER_ID(bfpt_header) != SFDP_BFPT_ID ||
+	    bfpt_header->major != SFDP_JESD216_MAJOR)
+		return -EINVAL;
+
+	/*
+	 * Allocate memory then read all parameter headers with a single
+	 * Read SFDP command. These parameter headers will actually be parsed
+	 * twice: a first time to get the latest revision of the basic flash
+	 * parameter table, then a second time to handle the supported optional
+	 * tables.
+	 * Hence we read the parameter headers once for all to reduce the
+	 * processing time. Also we use kmalloc() instead of devm_kmalloc()
+	 * because we don't need to keep these parameter headers: the allocated
+	 * memory is always released with kfree() before exiting this function.
+	 */
+	if (header.nph) {
+		psize = header.nph * sizeof(*param_headers);
+
+		param_headers = kmalloc(psize, GFP_KERNEL);
+		if (!param_headers)
+			return -ENOMEM;
+
+		err = spi_nor_read_sfdp(nor, sizeof(header),
+					psize, param_headers);
+		if (err < 0) {
+			dev_err(dev, "failed to read SFDP parameter headers\n");
+			goto exit;
+		}
+	}
+
+	/*
+	 * Check other parameter headers to get the latest revision of
+	 * the basic flash parameter table.
+	 */
+	for (i = 0; i < header.nph; i++) {
+		param_header = &param_headers[i];
+
+		if (SFDP_PARAM_HEADER_ID(param_header) == SFDP_BFPT_ID &&
+		    param_header->major == SFDP_JESD216_MAJOR &&
+		    (param_header->minor > bfpt_header->minor ||
+		     (param_header->minor == bfpt_header->minor &&
+		      param_header->length > bfpt_header->length)))
+			bfpt_header = param_header;
+	}
+
+	err = spi_nor_parse_bfpt(nor, bfpt_header, params);
+	if (err)
+		goto exit;
+
+	/* Parse other parameter headers. */
+	for (i = 0; i < header.nph; i++) {
+		param_header = &param_headers[i];
+
+		switch (SFDP_PARAM_HEADER_ID(param_header)) {
+		case SFDP_SECTOR_MAP_ID:
+			err = spi_nor_parse_smpt(nor, param_header);
+			break;
+
+		default:
+			break;
+		}
+
+		if (err)
+			goto exit;
+	}
+
+exit:
+	kfree(param_headers);
+	return err;
+}
-- 
2.17.1


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