This table is indication that the flash is xSPI compliant and hence supports octal DTR mode. Extract information like the fast read opcode, the number of dummy cycles needed for a Read Status Register command, and the number of address bytes needed for a Read Status Register command.
The default dummy cycles for a fast octal DTR read are set to 20. Since there is no simple way of determining the dummy cycles needed for the fast read command, flashes that use a different value should update it in their flash-specific hooks.
Signed-off-by: Pratyush Yadav p.yadav@ti.com --- drivers/mtd/spi/spi-nor-core.c | 100 +++++++++++++++++++++++++++++++++ include/linux/mtd/spi-nor.h | 7 +++ 2 files changed, 107 insertions(+)
diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c index 86bf7e3efd..933f11c5fd 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -21,6 +21,7 @@ #include <linux/log2.h> #include <linux/math64.h> #include <linux/sizes.h> +#include <linux/bitfield.h>
#include <linux/mtd/mtd.h> #include <linux/mtd/spi-nor.h> @@ -40,6 +41,8 @@
#define DEFAULT_READY_WAIT_JIFFIES (40UL * HZ)
+#define ROUND_UP_TO(x, y) (((x) + (y) - 1) / (y) * (y)) + struct sfdp_parameter_header { u8 id_lsb; u8 minor; @@ -58,6 +61,7 @@ struct sfdp_parameter_header { #define SFDP_BFPT_ID 0xff00 /* Basic Flash Parameter Table */ #define SFDP_SECTOR_MAP_ID 0xff81 /* Sector Map Table */ #define SFDP_SST_ID 0x01bf /* Manufacturer specific Table */ +#define SFDP_PROFILE1_ID 0xff05 /* xSPI Profile 1.0 Table */
#define SFDP_SIGNATURE 0x50444653U #define SFDP_JESD216_MAJOR 1 @@ -155,6 +159,16 @@ struct sfdp_header { #define BFPT_DWORD18_CMD_EXT_RES (0x2UL << 29) /* Reserved */ #define BFPT_DWORD18_CMD_EXT_16B (0x3UL << 29) /* 16-bit opcode */
+/* xSPI Profile 1.0 table (from JESD216D.01). */ +#define PROFILE1_DWORD1_RD_FAST_CMD GENMASK(15, 8) +#define PROFILE1_DWORD1_RDSR_DUMMY BIT(28) +#define PROFILE1_DWORD1_RDSR_ADDR_BYTES BIT(29) +#define PROFILE1_DWORD4_DUMMY_200MHZ GENMASK(11, 7) +#define PROFILE1_DWORD5_DUMMY_166MHZ GENMASK(31, 27) +#define PROFILE1_DWORD5_DUMMY_133MHZ GENMASK(21, 17) +#define PROFILE1_DWORD5_DUMMY_100MHZ GENMASK(11, 7) +#define PROFILE1_DUMMY_DEFAULT 20 + struct sfdp_bfpt { u32 dwords[BFPT_DWORD_MAX]; }; @@ -2095,6 +2109,86 @@ spi_nor_parse_microchip_sfdp(struct spi_nor *nor, return ret; }
+/** + * spi_nor_parse_profile1() - parse the xSPI Profile 1.0 table + * @nor: pointer to a 'struct spi_nor' + * @profile1_header: pointer to the 'struct sfdp_parameter_header' describing + * the 4-Byte Address Instruction Table length and version. + * @params: pointer to the 'struct spi_nor_flash_parameter' to be. + * + * Return: 0 on success, -errno otherwise. + */ +static int spi_nor_parse_profile1(struct spi_nor *nor, + const struct sfdp_parameter_header *profile1_header, + struct spi_nor_flash_parameter *params) +{ + u32 *table, opcode, addr; + size_t len; + int ret, i; + u8 dummy; + + len = profile1_header->length * sizeof(*table); + table = kmalloc(len, GFP_KERNEL); + if (!table) + return -ENOMEM; + + addr = SFDP_PARAM_HEADER_PTP(profile1_header); + ret = spi_nor_read_sfdp(nor, addr, len, table); + if (ret) + goto out; + + /* Fix endianness of the table DWORDs. */ + for (i = 0; i < profile1_header->length; i++) + table[i] = le32_to_cpu(table[i]); + + /* Get 8D-8D-8D fast read opcode and dummy cycles. */ + opcode = FIELD_GET(PROFILE1_DWORD1_RD_FAST_CMD, table[0]); + + /* + * We don't know what speed the controller is running at. Find the + * dummy cycles for the fastest frequency the flash can run at to be + * sure we are never short of dummy cycles. A value of 0 means the + * frequency is not supported. + * + * Default to PROFILE1_DUMMY_DEFAULT if we don't find anything, and let + * flashes set the correct value if needed in their fixup hooks. + */ + dummy = FIELD_GET(PROFILE1_DWORD4_DUMMY_200MHZ, table[3]); + if (!dummy) + dummy = FIELD_GET(PROFILE1_DWORD5_DUMMY_166MHZ, table[4]); + if (!dummy) + dummy = FIELD_GET(PROFILE1_DWORD5_DUMMY_133MHZ, table[4]); + if (!dummy) + dummy = FIELD_GET(PROFILE1_DWORD5_DUMMY_100MHZ, table[4]); + if (!dummy) + dummy = PROFILE1_DUMMY_DEFAULT; + + /* Round up to an even value to avoid tripping controllers up. */ + dummy = ROUND_UP_TO(dummy, 2); + + /* Update the fast read settings. */ + spi_nor_set_read_settings(¶ms->reads[SNOR_CMD_READ_8_8_8_DTR], + 0, dummy, opcode, + SNOR_PROTO_8_8_8_DTR); + + /* + * Set the Read Status Register dummy cycles and dummy address bytes. + */ + if (table[0] & PROFILE1_DWORD1_RDSR_DUMMY) + params->rdsr_dummy = 8; + else + params->rdsr_dummy = 4; + + if (table[0] & PROFILE1_DWORD1_RDSR_ADDR_BYTES) + params->rdsr_addr_nbytes = 4; + else + params->rdsr_addr_nbytes = 0; + +out: + kfree(table); + return ret; +} + /** * spi_nor_parse_sfdp() - parse the Serial Flash Discoverable Parameters. * @nor: pointer to a 'struct spi_nor' @@ -2197,6 +2291,10 @@ static int spi_nor_parse_sfdp(struct spi_nor *nor, err = spi_nor_parse_microchip_sfdp(nor, param_header); break;
+ case SFDP_PROFILE1_ID: + err = spi_nor_parse_profile1(nor, param_header, params); + break; + default: break; } @@ -2925,6 +3023,8 @@ int spi_nor_scan(struct spi_nor *nor) if (ret) return ret;
+ nor->rdsr_dummy = params.rdsr_dummy; + nor->rdsr_addr_nbytes = params.rdsr_addr_nbytes; nor->name = mtd->name; nor->size = mtd->size; nor->erase_size = mtd->erasesize; diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index 4394cb6e16..295583ed29 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -391,6 +391,8 @@ enum spi_nor_pp_command_index { struct spi_nor_flash_parameter { u64 size; u32 page_size; + u8 rdsr_dummy; + u8 rdsr_addr_nbytes;
struct spi_nor_hwcaps hwcaps; struct spi_nor_read_command reads[SNOR_CMD_READ_MAX]; @@ -445,6 +447,9 @@ struct spi_flash { * @read_opcode: the read opcode * @read_dummy: the dummy needed by the read operation * @program_opcode: the program opcode + * @rdsr_dummy dummy cycles needed for Read Status Register command. + * @rdsr_addr_nbytes: dummy address bytes needed for Read Status Register + * command. * @bank_read_cmd: Bank read cmd * @bank_write_cmd: Bank write cmd * @bank_curr: Current flash bank @@ -486,6 +491,8 @@ struct spi_nor { u8 read_opcode; u8 read_dummy; u8 program_opcode; + u8 rdsr_dummy; + u8 rdsr_addr_nbytes; #ifdef CONFIG_SPI_FLASH_BAR u8 bank_read_cmd; u8 bank_write_cmd;