mtd: spi-nor: parse Serial Flash Discoverable Parameters (SFDP) tables

This patch adds support to the JESD216 rev B standard and parses the SFDP
tables to dynamically initialize the 'struct spi_nor_flash_parameter'.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@microchip.com>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
This commit is contained in:
Cyrille Pitchen 2017-06-26 15:10:00 +02:00 committed by Cyrille Pitchen
parent 5771a8c088
commit f384b352cb
2 changed files with 768 additions and 13 deletions

View File

@ -17,6 +17,7 @@
#include <linux/mutex.h>
#include <linux/math64.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/mtd/mtd.h>
#include <linux/of_platform.h>
@ -86,6 +87,7 @@ struct flash_info {
* to support memory size above 128Mib.
*/
#define NO_CHIP_ERASE BIT(12) /* Chip does not support chip erase */
#define SPI_NOR_SKIP_SFDP BIT(13) /* Skip parsing of SFDP tables */
};
#define JEDEC_MFR(info) ((info)->id[0])
@ -1380,6 +1382,16 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
return ret;
}
/**
* macronix_quad_enable() - set QE bit in Status Register.
* @nor: pointer to a 'struct spi_nor'
*
* Set the Quad Enable (QE) bit in the Status Register.
*
* bit 6 of the Status Register is the QE bit for Macronix like QSPI memories.
*
* Return: 0 on success, -errno otherwise.
*/
static int macronix_quad_enable(struct spi_nor *nor)
{
int ret, val;
@ -1413,22 +1425,13 @@ static int macronix_quad_enable(struct spi_nor *nor)
* second byte will be written to the configuration register.
* Return negative if error occurred.
*/
static int write_sr_cr(struct spi_nor *nor, u16 val)
{
nor->cmd_buf[0] = val & 0xff;
nor->cmd_buf[1] = (val >> 8);
return nor->write_reg(nor, SPINOR_OP_WRSR, nor->cmd_buf, 2);
}
static int spansion_quad_enable(struct spi_nor *nor)
static int write_sr_cr(struct spi_nor *nor, u8 *sr_cr)
{
int ret;
int quad_en = CR_QUAD_EN_SPAN << 8;
write_enable(nor);
ret = write_sr_cr(nor, quad_en);
ret = nor->write_reg(nor, SPINOR_OP_WRSR, sr_cr, 2);
if (ret < 0) {
dev_err(nor->dev,
"error while writing configuration register\n");
@ -1442,6 +1445,41 @@ static int spansion_quad_enable(struct spi_nor *nor)
return ret;
}
return 0;
}
/**
* spansion_quad_enable() - set QE bit in Configuraiton Register.
* @nor: pointer to a 'struct spi_nor'
*
* Set the Quad Enable (QE) bit in the Configuration Register.
* This function is kept for legacy purpose because it has been used for a
* long time without anybody complaining but it should be considered as
* deprecated and maybe buggy.
* First, this function doesn't care about the previous values of the Status
* and Configuration Registers when it sets the QE bit (bit 1) in the
* Configuration Register: all other bits are cleared, which may have unwanted
* side effects like removing some block protections.
* Secondly, it uses the Read Configuration Register (35h) instruction though
* some very old and few memories don't support this instruction. If a pull-up
* resistor is present on the MISO/IO1 line, we might still be able to pass the
* "read back" test because the QSPI memory doesn't recognize the command,
* so leaves the MISO/IO1 line state unchanged, hence read_cr() returns 0xFF.
*
* bit 1 of the Configuration Register is the QE bit for Spansion like QSPI
* memories.
*
* Return: 0 on success, -errno otherwise.
*/
static int spansion_quad_enable(struct spi_nor *nor)
{
u8 sr_cr[2] = {0, CR_QUAD_EN_SPAN};
int ret;
ret = write_sr_cr(nor, sr_cr);
if (ret)
return ret;
/* read back and check it */
ret = read_cr(nor);
if (!(ret > 0 && (ret & CR_QUAD_EN_SPAN))) {
@ -1452,6 +1490,140 @@ static int spansion_quad_enable(struct spi_nor *nor)
return 0;
}
/**
* spansion_no_read_cr_quad_enable() - set QE bit in Configuration Register.
* @nor: pointer to a 'struct spi_nor'
*
* Set the Quad Enable (QE) bit in the Configuration Register.
* This function should be used with QSPI memories not supporting the Read
* Configuration Register (35h) instruction.
*
* bit 1 of the Configuration Register is the QE bit for Spansion like QSPI
* memories.
*
* Return: 0 on success, -errno otherwise.
*/
static int spansion_no_read_cr_quad_enable(struct spi_nor *nor)
{
u8 sr_cr[2];
int ret;
/* Keep the current value of the Status Register. */
ret = read_sr(nor);
if (ret < 0) {
dev_err(nor->dev, "error while reading status register\n");
return -EINVAL;
}
sr_cr[0] = ret;
sr_cr[1] = CR_QUAD_EN_SPAN;
return write_sr_cr(nor, sr_cr);
}
/**
* spansion_read_cr_quad_enable() - set QE bit in Configuration Register.
* @nor: pointer to a 'struct spi_nor'
*
* Set the Quad Enable (QE) bit in the Configuration Register.
* This function should be used with QSPI memories supporting the Read
* Configuration Register (35h) instruction.
*
* bit 1 of the Configuration Register is the QE bit for Spansion like QSPI
* memories.
*
* Return: 0 on success, -errno otherwise.
*/
static int spansion_read_cr_quad_enable(struct spi_nor *nor)
{
struct device *dev = nor->dev;
u8 sr_cr[2];
int ret;
/* Check current Quad Enable bit value. */
ret = read_cr(nor);
if (ret < 0) {
dev_err(dev, "error while reading configuration register\n");
return -EINVAL;
}
if (ret & CR_QUAD_EN_SPAN)
return 0;
sr_cr[1] = ret | CR_QUAD_EN_SPAN;
/* Keep the current value of the Status Register. */
ret = read_sr(nor);
if (ret < 0) {
dev_err(dev, "error while reading status register\n");
return -EINVAL;
}
sr_cr[0] = ret;
ret = write_sr_cr(nor, sr_cr);
if (ret)
return ret;
/* Read back and check it. */
ret = read_cr(nor);
if (!(ret > 0 && (ret & CR_QUAD_EN_SPAN))) {
dev_err(nor->dev, "Spansion Quad bit not set\n");
return -EINVAL;
}
return 0;
}
/**
* sr2_bit7_quad_enable() - set QE bit in Status Register 2.
* @nor: pointer to a 'struct spi_nor'
*
* Set the Quad Enable (QE) bit in the Status Register 2.
*
* This is one of the procedures to set the QE bit described in the SFDP
* (JESD216 rev B) specification but no manufacturer using this procedure has
* been identified yet, hence the name of the function.
*
* Return: 0 on success, -errno otherwise.
*/
static int sr2_bit7_quad_enable(struct spi_nor *nor)
{
u8 sr2;
int ret;
/* Check current Quad Enable bit value. */
ret = nor->read_reg(nor, SPINOR_OP_RDSR2, &sr2, 1);
if (ret)
return ret;
if (sr2 & SR2_QUAD_EN_BIT7)
return 0;
/* Update the Quad Enable bit. */
sr2 |= SR2_QUAD_EN_BIT7;
write_enable(nor);
ret = nor->write_reg(nor, SPINOR_OP_WRSR2, &sr2, 1);
if (ret < 0) {
dev_err(nor->dev, "error while writing status register 2\n");
return -EINVAL;
}
ret = spi_nor_wait_till_ready(nor);
if (ret < 0) {
dev_err(nor->dev, "timeout while writing status register 2\n");
return ret;
}
/* Read back and check it. */
ret = nor->read_reg(nor, SPINOR_OP_RDSR2, &sr2, 1);
if (!(ret > 0 && (sr2 & SR2_QUAD_EN_BIT7))) {
dev_err(nor->dev, "SR2 Quad bit not set\n");
return -EINVAL;
}
return 0;
}
static int spi_nor_check(struct spi_nor *nor)
{
if (!nor->dev || !nor->read || !nor->write ||
@ -1591,6 +1763,560 @@ spi_nor_set_pp_settings(struct spi_nor_pp_command *pp,
pp->proto = proto;
}
/*
* Serial Flash Discoverable Parameters (SFDP) parsing.
*/
/**
* 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
*
* 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;
while (len) {
ret = nor->read(nor, addr, len, (u8 *)buf);
if (!ret || ret > len) {
ret = -EIO;
goto read_err;
}
if (ret < 0)
goto read_err;
buf += ret;
addr += ret;
len -= ret;
}
ret = 0;
read_err:
nor->read_opcode = read_opcode;
nor->addr_width = addr_width;
nor->read_dummy = read_dummy;
return ret;
}
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;
};
#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
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;
};
/* 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];
};
/* Fast Read settings. */
static inline 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_hwcaps_read2cmd(u32 hwcaps);
/**
* 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 mtd_info *mtd = &nor->mtd;
struct sfdp_bfpt bfpt;
size_t len;
int i, cmd, err;
u32 addr;
u16 half;
/* 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(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);
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. */
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;
#ifdef CONFIG_MTD_SPI_NOR_USE_4K_SECTORS
if (erasesize == SZ_4K) {
nor->erase_opcode = opcode;
mtd->erasesize = erasesize;
break;
}
#endif
if (!mtd->erasesize || mtd->erasesize < erasesize) {
nor->erase_opcode = opcode;
mtd->erasesize = erasesize;
}
}
/* 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. */
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 = NULL;
break;
case BFPT_DWORD15_QER_SR2_BIT1_BUGGY:
case BFPT_DWORD15_QER_SR2_BIT1_NO_RD:
params->quad_enable = spansion_no_read_cr_quad_enable;
break;
case BFPT_DWORD15_QER_SR1_BIT6:
params->quad_enable = macronix_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 = spansion_read_cr_quad_enable;
break;
default:
return -EINVAL;
}
return 0;
}
/**
* 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(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 ||
header.minor < SFDP_JESD216_MINOR)
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:
dev_info(dev, "non-uniform erase sector maps are not supported yet.\n");
break;
default:
break;
}
if (err)
goto exit;
}
exit:
kfree(param_headers);
return err;
}
static int spi_nor_init_params(struct spi_nor *nor,
const struct flash_info *info,
struct spi_nor_flash_parameter *params)
@ -1646,11 +2372,28 @@ static int spi_nor_init_params(struct spi_nor *nor,
break;
default:
/* Kept only for backward compatibility purpose. */
params->quad_enable = spansion_quad_enable;
break;
}
}
/* Override the parameters with data read from SFDP tables. */
nor->addr_width = 0;
nor->mtd.erasesize = 0;
if ((info->flags & (SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ)) &&
!(info->flags & SPI_NOR_SKIP_SFDP)) {
struct spi_nor_flash_parameter sfdp_params;
memcpy(&sfdp_params, params, sizeof(sfdp_params));
if (spi_nor_parse_sfdp(nor, &sfdp_params)) {
nor->addr_width = 0;
nor->mtd.erasesize = 0;
} else {
memcpy(params, &sfdp_params, sizeof(*params));
}
}
return 0;
}
@ -1762,6 +2505,10 @@ static int spi_nor_select_erase(struct spi_nor *nor,
{
struct mtd_info *mtd = &nor->mtd;
/* Do nothing if already configured from SFDP. */
if (mtd->erasesize)
return 0;
#ifdef CONFIG_MTD_SPI_NOR_USE_4K_SECTORS
/* prefer "small sector" erase if possible */
if (info->flags & SECT_4K) {
@ -1994,9 +2741,11 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
if (ret)
return ret;
if (info->addr_width)
if (nor->addr_width) {
/* already configured from SFDP */
} else if (info->addr_width) {
nor->addr_width = info->addr_width;
else if (mtd->size > 0x1000000) {
} else if (mtd->size > 0x1000000) {
/* enable 4-byte addressing if the device exceeds 16MiB */
nor->addr_width = 4;
if (JEDEC_MFR(info) == SNOR_MFR_SPANSION ||

View File

@ -41,6 +41,8 @@
#define SPINOR_OP_WREN 0x06 /* Write enable */
#define SPINOR_OP_RDSR 0x05 /* Read status register */
#define SPINOR_OP_WRSR 0x01 /* Write status register 1 byte */
#define SPINOR_OP_RDSR2 0x3f /* Read status register 2 */
#define SPINOR_OP_WRSR2 0x3e /* Write status register 2 */
#define SPINOR_OP_READ 0x03 /* Read data bytes (low frequency) */
#define SPINOR_OP_READ_FAST 0x0b /* Read data bytes (high frequency) */
#define SPINOR_OP_READ_1_1_2 0x3b /* Read data bytes (Dual Output SPI) */
@ -56,6 +58,7 @@
#define SPINOR_OP_CHIP_ERASE 0xc7 /* Erase whole flash chip */
#define SPINOR_OP_SE 0xd8 /* Sector erase (usually 64KiB) */
#define SPINOR_OP_RDID 0x9f /* Read JEDEC ID */
#define SPINOR_OP_RDSFDP 0x5a /* Read SFDP */
#define SPINOR_OP_RDCR 0x35 /* Read configuration register */
#define SPINOR_OP_RDFSR 0x70 /* Read flag status register */
@ -128,6 +131,9 @@
/* Configuration Register bits. */
#define CR_QUAD_EN_SPAN BIT(1) /* Spansion Quad I/O */
/* Status Register 2 bits. */
#define SR2_QUAD_EN_BIT7 BIT(7)
/* Supported SPI protocols */
#define SNOR_PROTO_INST_MASK GENMASK(23, 16)
#define SNOR_PROTO_INST_SHIFT 16