From f384b352cbf0310fd20c379c4710408c70e769b6 Mon Sep 17 00:00:00 2001 From: Cyrille Pitchen Date: Mon, 26 Jun 2017 15:10:00 +0200 Subject: [PATCH] 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 Reviewed-by: Marek Vasut --- drivers/mtd/spi-nor/spi-nor.c | 775 +++++++++++++++++++++++++++++++++- include/linux/mtd/spi-nor.h | 6 + 2 files changed, 768 insertions(+), 13 deletions(-) diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index 1413828ff1fb..196b52f083ae 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -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 @@ write_err: 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 bit in 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 in 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 in DWORD 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 = ¶ms->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 = ¶m_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 = ¶m_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 || diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index 55faa2f07cca..0df3638ff0b8 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -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 -- 2.20.1