Re: [U-Boot] [PATCH 1/3] mtd/spi: Add JEDEC SFDP support in SPI framework

On 17/10/18 4:58 PM, Rajat Srivastava wrote:

Add support for JESD216 rev B standard JEDEC Serial Flash Discoverable Parameters (SFDP) tables to dynamically initialize flash size, page size and address width of the flash. More parameters can be added as per requirement. Already existing method for parsing these parameters are not deprecated, which can be done once most flash start using SFDP data.

SFDP data lets us auto-detect the addressing mode supported by the flash which helps us access the flash using 4-byte address.

Add a new argument in spi_flash_addr() function to create commands with 3-byte or 4-byte address depending on the SFDP data read. Add pointer to struct spi_flash in struct spi_slave so that driver can have access to SFDP data.

Introduce new structures and functions to read and parse SFDP data. This is loosely based on Linux SFDP framework.

Signed-off-by: Rajat Srivastava rajat.srivastava@nxp.com

drivers/mtd/spi/sf_internal.h | 4 + drivers/mtd/spi/spi_flash.c | 297 +++++++++++++++++++++++++++++++++++++++--- include/spi.h | 2 + include/spi_flash.h | 120 +++++++++++++++++ 4 files changed, 403 insertions(+), 20 deletions(-)

diff --git a/drivers/mtd/spi/sf_internal.h b/drivers/mtd/spi/sf_internal.h index 26f5c7c995..1bb4431d84 100644 --- a/drivers/mtd/spi/sf_internal.h +++ b/drivers/mtd/spi/sf_internal.h @@ -26,7 +26,9 @@ enum spi_nor_option_flags { };

#define SPI_FLASH_3B_ADDR_LEN 3 +#define SPI_FLASH_4B_ADDR_LEN 4 #define SPI_FLASH_CMD_LEN (1 + SPI_FLASH_3B_ADDR_LEN) +#define SPI_FLASH_CMD_MAX_LEN (1 + SPI_FLASH_4B_ADDR_LEN) #define SPI_FLASH_16MB_BOUN 0x1000000

/* CFI Manufacture ID's */ @@ -62,6 +64,7 @@ enum spi_nor_option_flags { #define CMD_READ_STATUS1 0x35 #define CMD_READ_CONFIG 0x35 #define CMD_FLAG_STATUS 0x70 +#define CMD_READ_SFDP 0x5a

/* Bank addr access commands */ #ifdef CONFIG_SPI_FLASH_BAR @@ -144,6 +147,7 @@ struct spi_flash_info { #define RD_DUAL BIT(5) /* use Dual Read */ #define RD_QUADIO BIT(6) /* use Quad IO Read */ #define RD_DUALIO BIT(7) /* use Dual IO Read */ +#define SPI_FLASH_USE_SFDP BIT(8) /* parse SFDP to get flash info */

I suggest to SFDP not be a opt-in but default option like Linux kernel, since that's SFDP is a standard. If flash does not support SFDP that can be detected by looking for SFPD signature and code can fallback gracefully. If a flash has a broken SFDP table then such parts can use "SPI_FLASH_BROKEN_SFDP" flag or something. That way we don't need to add above flag to almost all flash entries here.

Regards Vignesh

#define RD_FULL (RD_QUAD | RD_DUAL | RD_QUADIO | RD_DUALIO) };

diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c index a87bacd4ac..5d2728cc00 100644 --- a/drivers/mtd/spi/spi_flash.c +++ b/drivers/mtd/spi/spi_flash.c @@ -20,12 +20,24 @@

#include "sf_internal.h"

-static void spi_flash_addr(u32 addr, u8 *cmd) +static void spi_flash_addr(struct spi_flash *flash, u32 addr, u8 *cmd) { /* cmd[0] is actual command */

• cmd[1] = addr >> 16;
• cmd[2] = addr >> 8;
• cmd[3] = addr >> 0;

• int i;
• /* Remember to unset addrwd_3_in_use */
• if (flash->addrwd_3_in_use) {

• flash->addr_width = SPI_FLASH_3B_ADDR_LEN;
  

• debug("SF: addrwd_3_in_use flag needs to be reset to false ");
  

• debug("after the intended command is triggered to flash.\n");
  

• }
• flash->cmd_len = 1 + flash->addr_width;
• for (i = flash->cmd_len - 1; i > 0; i--) {

• cmd[i] = addr;
  

• addr = addr >> 8;
  

• }

}

static int read_sr(struct spi_flash *flash, u8 *rs) @@ -314,7 +326,7 @@ int spi_flash_write_common(struct spi_flash *flash, const u8 *cmd, int spi_flash_cmd_erase_ops(struct spi_flash *flash, u32 offset, size_t len) { u32 erase_size, erase_addr;

• u8 cmd[SPI_FLASH_CMD_LEN];

• u8 cmd[SPI_FLASH_CMD_MAX_LEN]; int ret = -1;

  erase_size = flash->erase_size;

@@ -344,12 +356,13 @@ int spi_flash_cmd_erase_ops(struct spi_flash *flash, u32 offset, size_t len) if (ret < 0) return ret; #endif

• spi_flash_addr(erase_addr, cmd);
  

• spi_flash_addr(flash, erase_addr, cmd);
  
  

  debug("SF: erase %2x %2x %2x %2x (%x)\n", cmd[0], cmd[1], cmd[2], cmd[3], erase_addr);

• ret = spi_flash_write_common(flash, cmd, sizeof(cmd), NULL, 0);
  

• ret = spi_flash_write_common(flash, cmd, flash->cmd_len,
  

• 			     NULL, 0);
  

  if (ret < 0) { debug("SF: erase failed\n"); break;

@@ -373,7 +386,7 @@ int spi_flash_cmd_write_ops(struct spi_flash *flash, u32 offset, unsigned long byte_addr, page_size; u32 write_addr; size_t chunk_len, actual;

• u8 cmd[SPI_FLASH_CMD_LEN];

• u8 cmd[SPI_FLASH_CMD_MAX_LEN]; int ret = -1;

  page_size = flash->page_size;

@@ -406,13 +419,13 @@ int spi_flash_cmd_write_ops(struct spi_flash *flash, u32 offset, chunk_len = min(chunk_len, spi->max_write_size - sizeof(cmd));

• spi_flash_addr(write_addr, cmd);
  

• spi_flash_addr(flash, write_addr, cmd);
  
  

  debug("SF: 0x%p => cmd = { 0x%02x 0x%02x%02x%02x } chunk_len = %zu\n", buf + actual, cmd[0], cmd[1], cmd[2], cmd[3], chunk_len);

• ret = spi_flash_write_common(flash, cmd, sizeof(cmd),
  

• 			buf + actual, chunk_len);
  

• ret = spi_flash_write_common(flash, cmd, flash->cmd_len,
  

• 			     buf + actual, chunk_len);
  

  if (ret < 0) { debug("SF: write failed\n"); break;

@@ -487,7 +500,7 @@ int spi_flash_cmd_read_ops(struct spi_flash *flash, u32 offset, return 0; }

• cmdsz = SPI_FLASH_CMD_LEN + flash->dummy_byte;

• cmdsz = flash->cmd_len + flash->dummy_byte; u8 cmd[cmdsz];

  cmd[0] = flash->read_cmd;

@@ -504,8 +517,11 @@ int spi_flash_cmd_read_ops(struct spi_flash *flash, u32 offset, return log_ret(ret); bank_sel = flash->bank_curr; #endif

• remain_len = ((SPI_FLASH_16MB_BOUN << flash->shift) *
  

• 		(bank_sel + 1)) - offset;
  

• if (flash->cmd_len == SPI_FLASH_CMD_MAX_LEN)
  

• 	remain_len = flash->size - offset;
  

• else
  

• 	remain_len = ((SPI_FLASH_16MB_BOUN << flash->shift) *
  

• 		      (bank_sel + 1)) - offset;
  

  if (len < remain_len) read_len = len; else

@@ -514,7 +530,7 @@ int spi_flash_cmd_read_ops(struct spi_flash *flash, u32 offset, if (spi->max_read_size) read_len = min(read_len, spi->max_read_size);

• spi_flash_addr(read_addr, cmd);
  

• spi_flash_addr(flash, read_addr, cmd);
  
  

  ret = spi_flash_read_common(flash, cmd, cmdsz, data, read_len); if (ret < 0) {

@@ -1076,6 +1092,226 @@ static const struct spi_flash_info *spi_flash_read_id(struct spi_flash *flash) return ERR_PTR(-ENODEV); }

+/*

• • Serial Flash Discoverable Parameters (SFDP) parsing
• */

+/*

• • spi_flash_read_sfdp() - read Serial Flash Discoverable Parameters.
• • @flash: pointer to a 'struct spi_flash'
• • @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
• • Return: 0 on success, -errno otherwise.
• */

+static int spi_flash_read_sfdp(struct spi_flash *flash, u32 addr, size_t len,

• 	       void *buf)
  

+{

• u8 cmd[4];
• int ret;
• cmd[0] = CMD_READ_SFDP;
• /*

• * In case of flashes that support 3 or 4-byte addressing modes
  

• * based on command fired, CMD_READ_SFDP is a 3-byte command.
  

• * To make sure a 3-byte command is fired, change addrwd_3_in_use
  

• * to true and reset it after triggering the command.
  

• */
  

• flash->addrwd_3_in_use = true;
• spi_flash_addr(flash, addr, cmd);
• flash->addrwd_3_in_use = false;
• ret = spi_flash_read_common(flash, cmd, 4, buf, len);
• if (ret)

• return -EIO;
  

• return 0;

+}

+/**

• • spi_flash_parse_bfpt() - read and parse the Basic Flash Parameter Table.
• • @flash: pointer to a 'struct spi_flash'
• • @bfpt_header: pointer to the 'struct sfdp_parameter_header' describing

• • 	the Basic Flash Parameter Table length and version
    

• • 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, page
• • size and the number of address bytes to perform flash operations, among
• • other information.
• • Return: 0 on success, -errno otherwise.
• */

+static int spi_flash_parse_bfpt(struct spi_flash *flash,

• 		const struct sfdp_parameter_header *bfpt_header)
  

+{

• struct sfdp_bfpt bfpt;
• size_t len;
• int i, err;
• u32 addr;
• /* 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_flash_read_sfdp(flash, 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:

• flash->addr_width = 3;
  

• break;
  

• case BFPT_DWORD1_ADDRESS_BYTES_3_OR_4:

• printf("SF: Flash defaults to 3-Byte mode; enters 4-Byte ");
  

• printf("mode on command\n");
  

• /*
  

•  * By default, 4-byte addressing mode is set.
  

•  * To enforce 3-byte addressing mode, set addrwd_3_in_use flag
  

•  * in struct spi_flash for every command.
  

•  */
  

• flash->addr_width = 4;
  

• break;
  

• case BFPT_DWORD1_ADDRESS_BYTES_4_ONLY:

• flash->addr_width = 4;
  

• break;
  

• default:

• break;
  

• }
• /* Flash Memory Density (in bits). */
• flash->size = bfpt.dwords[BFPT_DWORD(2)];
• if (flash->size & BIT(31)) {

• flash->size &= ~BIT(31);
  

• /*
  

•  * Prevent overflows on flash->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 (flash->size > 63)
  

• 	return -EINVAL;
  

• flash->size = 1ULL << flash->size;
  

• } else {

• flash->size++;
  

• }
• flash->size >>= 3; /* Convert to bytes. */
• /* Stop here if not JESD216 rev A or later. */
• if (bfpt_header->length < BFPT_DWORD_MAX)

• return 0;
  

• /* Page size: this field specifies 'N' so the page size = 2^N bytes. */
• flash->page_size = bfpt.dwords[BFPT_DWORD(11)];
• flash->page_size &= BFPT_DWORD11_PAGE_SIZE_MASK;
• flash->page_size >>= BFPT_DWORD11_PAGE_SIZE_SHIFT;
• flash->page_size = 1U << flash->page_size;
• return 0;

+}

+/*

• • spi_flash_parse_sfdp() - parse the Serial Flash Discoverable Parameters.
• • @flash: pointer to a 'struct spi_flash'
• • 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.
• • Return: 0 on success, -errno otherwise.
• */

+static int spi_flash_parse_sfdp(struct spi_flash *flash) +{

• const struct sfdp_parameter_header *param_header, *bfpt_header;
• struct sfdp_parameter_header *param_headers = NULL;
• struct sfdp_header header;
• size_t psize;
• int i, err;
• /* Get the SFDP header. */
• err = spi_flash_read_sfdp(flash, 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
  

• */
  

• if (header.nph) {

• psize = header.nph * sizeof(*param_headers);
  

• param_headers = malloc(psize);
  

• if (!param_headers)
  

• 	return -ENOMEM;
  

• err = spi_flash_read_sfdp(flash, 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_flash_parse_bfpt(flash, bfpt_header);
• if (err)

• goto exit;
  

+exit:

• free(param_headers);
• return err;

+}

static int set_quad_mode(struct spi_flash *flash, const struct spi_flash_info *info) { @@ -1196,9 +1432,26 @@ int spi_flash_scan(struct spi_flash *flash) } #endif

• spi->flash = flash;
• flash->addrwd_3_in_use = false;
• /* Read Serial Flash Discoverable Parameters and initialize

• * the following parameters of flash:
  

• * 1. Flash size
  

• * 2. Page size
  

• * 3. Address width to be used for commands
  

• */
  

• if (info->flags & SPI_FLASH_USE_SFDP) {

• flash->size = 0;
  

• spi_flash_parse_sfdp(flash);
  

• }
• /* Compute the flash size */ flash->shift = (flash->dual_flash & SF_DUAL_PARALLEL_FLASH) ? 1 : 0;

• flash->page_size = info->page_size;

• if (!(info->flags & SPI_FLASH_USE_SFDP)) {

• flash->page_size = info->page_size;
  

• flash->addr_width = SPI_FLASH_3B_ADDR_LEN;
  

• } /*
  • The Spansion S25FS512S, S25FL032P and S25FL064P have 256b pages,
  • yet use the 0x4d00 Extended JEDEC code. The rest of the Spansion

@@ -1213,7 +1466,10 @@ int spi_flash_scan(struct spi_flash *flash) } flash->page_size <<= flash->shift; flash->sector_size = info->sector_size << flash->shift;

• flash->size = flash->sector_size * info->n_sectors << flash->shift;

• if (!(info->flags & SPI_FLASH_USE_SFDP)) {

• flash->size = flash->sector_size * info->n_sectors <<
  

• 	flash->shift;
  

• }

#ifdef CONFIG_SF_DUAL_FLASH if (flash->dual_flash & SF_DUAL_STACKED_FLASH) flash->size <<= 1; @@ -1312,9 +1568,10 @@ int spi_flash_scan(struct spi_flash *flash) #endif

#ifndef CONFIG_SPI_FLASH_BAR

• if (((flash->dual_flash == SF_SINGLE_FLASH) &&

•     (flash->size > SPI_FLASH_16MB_BOUN)) ||
  

•     ((flash->dual_flash > SF_SINGLE_FLASH) &&
  

• if (!(info->flags & SPI_FLASH_USE_SFDP) &&

•    (flash->dual_flash == SF_SINGLE_FLASH &&
  

•     flash->size > SPI_FLASH_16MB_BOUN) ||
  

•     (flash->dual_flash > SF_SINGLE_FLASH &&
    (flash->size > SPI_FLASH_16MB_BOUN << 1))) {
  

  puts("SF: Warning - Only lower 16MiB accessible,"); puts(" Full access #define CONFIG_SPI_FLASH_BAR\n");

diff --git a/include/spi.h b/include/spi.h index 938627bc01..7189e60581 100644 --- a/include/spi.h +++ b/include/spi.h @@ -10,6 +10,7 @@ #define _SPI_H_

#include <common.h> +#include <spi_flash.h>

/* SPI mode flags */ #define SPI_CPHA BIT(0) /* clock phase */ @@ -103,6 +104,7 @@ struct spi_slave { unsigned int bus; unsigned int cs; #endif

• struct spi_flash *flash; uint mode; unsigned int wordlen; unsigned int max_read_size;

diff --git a/include/spi_flash.h b/include/spi_flash.h index 0ec98fb55d..6558a4a1d5 100644 --- a/include/spi_flash.h +++ b/include/spi_flash.h @@ -47,6 +47,9 @@ struct spi_slave;

• @read_cmd: Read cmd - Array Fast, Extn read and quad read.
• @write_cmd: Write cmd - page and quad program.
• @dummy_byte: Dummy cycles for read operation.

• • @cmd_len: Total length of command.
• • @addr_width: Number of address bytes.
• • @addrwd_3_in_use: Flag to send command in 3-byte address mode.
  • @memory_map: Address of read-only SPI flash access
  • @flash_lock: lock a region of the SPI Flash
  • @flash_unlock: unlock a region of the SPI Flash

@@ -82,6 +85,9 @@ struct spi_flash { u8 read_cmd; u8 write_cmd; u8 dummy_byte;

• u8 cmd_len;

• u8 addr_width;

• bool addrwd_3_in_use;

  void *memory_map;

@@ -107,6 +113,120 @@ struct spi_flash { #endif };

+/*

• • Serial Flash Discoverable Parameter Headers
• */

+struct sfdp_parameter_header {

• u8 id_lsb;
• u8 minor;
• u8 major;
• u8 length; /* in double words */
• u8 parameter_table_pointer[3]; /* byte address */
• u8 id_msb;

+};

+struct sfdp_header {

• u32 signature; /* Ox50444653U <=> "SFDP" */
• u8 minor;
• u8 major;
• u8 nph; /* 0-base number of parameter headers */
• u8 unused;
• /* Basic Flash Parameter Table. */
• struct sfdp_parameter_header bfpt_header;

+};

+#define SFDP_PARAM_HEADER_ID(p) (((p)->id_msb << 8) | (p)->id_lsb) +#define SFDP_PARAM_HEADER_PTP(p) \

• (((p)->parameter_table_pointer[2] << 16) | \

• ((p)->parameter_table_pointer[1] <<  8) | \
  

• ((p)->parameter_table_pointer[0] <<  0))
  

+#define SFDP_BFPT_ID 0xff00 /* Basic Flash Parameter Table */ +#define SFDP_SECTOR_MAP_ID 0xff81 /* Sector Map Table */

+#define SFDP_SIGNATURE 0x50444653U +#define SFDP_JESD216_MAJOR 1 +#define SFDP_JESD216_MINOR 0 +#define SFDP_JESD216A_MINOR 5 +#define SFDP_JESD216B_MINOR 6

+/* Basic Flash Parameter Table */

+/*

• • JESD216 rev B defines a Basic Flash Parameter Table of 16 DWORDs.
• • They are indexed from 1 but C arrays are indexed from 0.
• */

+#define BFPT_DWORD(i) ((i) - 1) +#define BFPT_DWORD_MAX 16

+/* The first version of JESB216 defined only 9 DWORDs. */ +#define BFPT_DWORD_MAX_JESD216 9

+/* 1st DWORD. */ +#define BFPT_DWORD1_FAST_READ_1_1_2 BIT(16) +#define BFPT_DWORD1_ADDRESS_BYTES_MASK GENMASK(18, 17) +#define BFPT_DWORD1_ADDRESS_BYTES_3_ONLY (0x0UL << 17) +#define BFPT_DWORD1_ADDRESS_BYTES_3_OR_4 (0x1UL << 17) +#define BFPT_DWORD1_ADDRESS_BYTES_4_ONLY (0x2UL << 17) +#define BFPT_DWORD1_DTR BIT(19) +#define BFPT_DWORD1_FAST_READ_1_2_2 BIT(20) +#define BFPT_DWORD1_FAST_READ_1_4_4 BIT(21) +#define BFPT_DWORD1_FAST_READ_1_1_4 BIT(22)

+/* 5th DWORD. */ +#define BFPT_DWORD5_FAST_READ_2_2_2 BIT(0) +#define BFPT_DWORD5_FAST_READ_4_4_4 BIT(4)

+/* 11th DWORD. */ +#define BFPT_DWORD11_PAGE_SIZE_SHIFT 4 +#define BFPT_DWORD11_PAGE_SIZE_MASK GENMASK(7, 4)

+/* 15th DWORD. */

+/*

• • (from JESD216 rev B)
• • Quad Enable Requirements (QER):
• • • 000b: Device does not have a QE bit. Device detects 1-1-4 and 1-4-4

• •     reads based on instruction. DQ3/HOLD# functions are hold during
    

• •     instruction phase.
    

• • • 001b: QE is bit 1 of status register 2. It is set via Write Status with

• •     two data bytes where bit 1 of the second byte is one.
    

• •     [...]
    

• •     Writing only one byte to the status register has the side-effect of
    

• •     clearing status register 2, including the QE bit. The 100b code is
    

• •     used if writing one byte to the status register does not modify
    

• •     status register 2.
    

• • • 010b: QE is bit 6 of status register 1. It is set via Write Status with

• •     one data byte where bit 6 is one.
    

• •     [...]
    

• • • 011b: QE is bit 7 of status register 2. It is set via Write status

• •     register 2 instruction 3Eh with one data byte where bit 7 is one.
    

• •     [...]
    

• •     The status register 2 is read using instruction 3Fh.
    

• • • 100b: QE is bit 1 of status register 2. It is set via Write Status with

• •     two data bytes where bit 1 of the second byte is one.
    

• •     [...]
    

• •     In contrast to the 001b code, writing one byte to the status
    

• •     register does not modify status register 2.
    

• • • 101b: QE is bit 1 of status register 2. Status register 1 is read using

• •     Read Status instruction 05h. Status register2 is read using
    

• •     instruction 35h. QE is set via Writ Status instruction 01h with
    

• •     two data bytes where bit 1 of the second byte is one.
    

• •     [...]
    

• */

+#define BFPT_DWORD15_QER_MASK GENMASK(22, 20) +#define BFPT_DWORD15_QER_NONE (0x0UL << 20) /* Micron */ +#define BFPT_DWORD15_QER_SR2_BIT1_BUGGY (0x1UL << 20) +#define BFPT_DWORD15_QER_SR1_BIT6 (0x2UL << 20) /* Macronix */ +#define BFPT_DWORD15_QER_SR2_BIT7 (0x3UL << 20) +#define BFPT_DWORD15_QER_SR2_BIT1_NO_RD (0x4UL << 20) +#define BFPT_DWORD15_QER_SR2_BIT1 (0x5UL << 20) /* Spansion */

+struct sfdp_bfpt {

• u32 dwords[BFPT_DWORD_MAX];

+};

struct dm_spi_flash_ops { int (*read)(struct udevice *dev, u32 offset, size_t len, void *buf); int (*write)(struct udevice *dev, u32 offset, size_t len,