Re: [PATCH v2 2/9] mtd: spi-nor: add an alternative method to support memory >16MiB

From: Vignesh R
Date: Thu Oct 13 2016 - 08:13:02 EST




On Wednesday 05 October 2016 05:30 PM, Cyrille Pitchen wrote:
> This patch provides an alternative mean to support memory above 16MiB
> (128Mib) by replacing 3byte address op codes by their associated 4byte
> address versions.
>
> Using the dedicated 4byte address op codes doesn't change the internal
> state of the SPI NOR memory as opposed to using other means such as
> updating a Base Address Register (BAR) and sending command to enter/leave
> the 4byte mode.
>
> Hence when a CPU reset occurs, early bootloaders don't need to be aware
> of BAR value or 4byte mode being enabled: they can still access the first
> 16MiB of the SPI NOR memory using the regular 3byte address op codes.
>

I am facing a similar issue on my am437x-idk board with mx66l51235l
flash and bootloader failed to access flash due to 4byte mode being
enabled. With SPI_NOR_4B_OPCODES flag set in mx66l51235l flash info and
this series applied, I can see that bootloader can now access flash.
Thanks for the patch!

FWIW, Tested-by: Vignesh R <vigneshr@xxxxxx>

> Signed-off-by: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxx>
> ---
> drivers/mtd/devices/serial_flash_cmds.h | 7 ---
> drivers/mtd/devices/st_spi_fsm.c | 28 ++++-----
> drivers/mtd/spi-nor/spi-nor.c | 104 +++++++++++++++++++++++++-------
> include/linux/mtd/spi-nor.h | 22 +++++--
> 4 files changed, 113 insertions(+), 48 deletions(-)
>
> diff --git a/drivers/mtd/devices/serial_flash_cmds.h b/drivers/mtd/devices/serial_flash_cmds.h
> index f59a125295d0..8b81e15105dd 100644
> --- a/drivers/mtd/devices/serial_flash_cmds.h
> +++ b/drivers/mtd/devices/serial_flash_cmds.h
> @@ -18,19 +18,12 @@
> #define SPINOR_OP_RDVCR 0x85
>
> /* JEDEC Standard - Serial Flash Discoverable Parmeters (SFDP) Commands */
> -#define SPINOR_OP_READ_1_2_2 0xbb /* DUAL I/O READ */
> -#define SPINOR_OP_READ_1_4_4 0xeb /* QUAD I/O READ */
> -
> #define SPINOR_OP_WRITE 0x02 /* PAGE PROGRAM */
> #define SPINOR_OP_WRITE_1_1_2 0xa2 /* DUAL INPUT PROGRAM */
> #define SPINOR_OP_WRITE_1_2_2 0xd2 /* DUAL INPUT EXT PROGRAM */
> #define SPINOR_OP_WRITE_1_1_4 0x32 /* QUAD INPUT PROGRAM */
> #define SPINOR_OP_WRITE_1_4_4 0x12 /* QUAD INPUT EXT PROGRAM */
>
> -/* READ commands with 32-bit addressing */
> -#define SPINOR_OP_READ4_1_2_2 0xbc
> -#define SPINOR_OP_READ4_1_4_4 0xec
> -
> /* Configuration flags */
> #define FLASH_FLAG_SINGLE 0x000000ff
> #define FLASH_FLAG_READ_WRITE 0x00000001
> diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c
> index 5454b4113589..804313a33f2b 100644
> --- a/drivers/mtd/devices/st_spi_fsm.c
> +++ b/drivers/mtd/devices/st_spi_fsm.c
> @@ -507,13 +507,13 @@ static struct seq_rw_config n25q_read3_configs[] = {
> * - 'FAST' variants configured for 8 dummy cycles (see note above.)
> */
> static struct seq_rw_config n25q_read4_configs[] = {
> - {FLASH_FLAG_READ_1_4_4, SPINOR_OP_READ4_1_4_4, 0, 4, 4, 0x00, 0, 8},
> - {FLASH_FLAG_READ_1_1_4, SPINOR_OP_READ4_1_1_4, 0, 1, 4, 0x00, 0, 8},
> - {FLASH_FLAG_READ_1_2_2, SPINOR_OP_READ4_1_2_2, 0, 2, 2, 0x00, 0, 8},
> - {FLASH_FLAG_READ_1_1_2, SPINOR_OP_READ4_1_1_2, 0, 1, 2, 0x00, 0, 8},
> - {FLASH_FLAG_READ_FAST, SPINOR_OP_READ4_FAST, 0, 1, 1, 0x00, 0, 8},
> - {FLASH_FLAG_READ_WRITE, SPINOR_OP_READ4, 0, 1, 1, 0x00, 0, 0},
> - {0x00, 0, 0, 0, 0, 0x00, 0, 0},
> + {FLASH_FLAG_READ_1_4_4, SPINOR_OP_READ_1_4_4_4B, 0, 4, 4, 0x00, 0, 8},
> + {FLASH_FLAG_READ_1_1_4, SPINOR_OP_READ_1_1_4_4B, 0, 1, 4, 0x00, 0, 8},
> + {FLASH_FLAG_READ_1_2_2, SPINOR_OP_READ_1_2_2_4B, 0, 2, 2, 0x00, 0, 8},
> + {FLASH_FLAG_READ_1_1_2, SPINOR_OP_READ_1_1_2_4B, 0, 1, 2, 0x00, 0, 8},
> + {FLASH_FLAG_READ_FAST, SPINOR_OP_READ_FAST_4B, 0, 1, 1, 0x00, 0, 8},
> + {FLASH_FLAG_READ_WRITE, SPINOR_OP_READ_4B, 0, 1, 1, 0x00, 0, 0},
> + {0x00, 0, 0, 0, 0, 0x00, 0, 0},
> };
>
> /*
> @@ -553,13 +553,13 @@ static int stfsm_mx25_en_32bit_addr_seq(struct stfsm_seq *seq)
> * entering a state that is incompatible with the SPIBoot Controller.
> */
> static struct seq_rw_config stfsm_s25fl_read4_configs[] = {
> - {FLASH_FLAG_READ_1_4_4, SPINOR_OP_READ4_1_4_4, 0, 4, 4, 0x00, 2, 4},
> - {FLASH_FLAG_READ_1_1_4, SPINOR_OP_READ4_1_1_4, 0, 1, 4, 0x00, 0, 8},
> - {FLASH_FLAG_READ_1_2_2, SPINOR_OP_READ4_1_2_2, 0, 2, 2, 0x00, 4, 0},
> - {FLASH_FLAG_READ_1_1_2, SPINOR_OP_READ4_1_1_2, 0, 1, 2, 0x00, 0, 8},
> - {FLASH_FLAG_READ_FAST, SPINOR_OP_READ4_FAST, 0, 1, 1, 0x00, 0, 8},
> - {FLASH_FLAG_READ_WRITE, SPINOR_OP_READ4, 0, 1, 1, 0x00, 0, 0},
> - {0x00, 0, 0, 0, 0, 0x00, 0, 0},
> + {FLASH_FLAG_READ_1_4_4, SPINOR_OP_READ_1_4_4_4B, 0, 4, 4, 0x00, 2, 4},
> + {FLASH_FLAG_READ_1_1_4, SPINOR_OP_READ_1_1_4_4B, 0, 1, 4, 0x00, 0, 8},
> + {FLASH_FLAG_READ_1_2_2, SPINOR_OP_READ_1_2_2_4B, 0, 2, 2, 0x00, 4, 0},
> + {FLASH_FLAG_READ_1_1_2, SPINOR_OP_READ_1_1_2_4B, 0, 1, 2, 0x00, 0, 8},
> + {FLASH_FLAG_READ_FAST, SPINOR_OP_READ_FAST_4B, 0, 1, 1, 0x00, 0, 8},
> + {FLASH_FLAG_READ_WRITE, SPINOR_OP_READ_4B, 0, 1, 1, 0x00, 0, 0},
> + {0x00, 0, 0, 0, 0, 0x00, 0, 0},
> };
>
> static struct seq_rw_config stfsm_s25fl_write4_configs[] = {
> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
> index 5c87b2d99507..423448c1c7a8 100644
> --- a/drivers/mtd/spi-nor/spi-nor.c
> +++ b/drivers/mtd/spi-nor/spi-nor.c
> @@ -75,6 +75,10 @@ struct flash_info {
> * bit. Must be used with
> * SPI_NOR_HAS_LOCK.
> */
> +#define SPI_NOR_4B_OPCODES BIT(10) /*
> + * Use dedicated 4byte address op codes
> + * to support memory size above 128Mib.
> + */
> };
>
> #define JEDEC_MFR(info) ((info)->id[0])
> @@ -188,6 +192,81 @@ static inline struct spi_nor *mtd_to_spi_nor(struct mtd_info *mtd)
> return mtd->priv;
> }
>
> +
> +struct spi_nor_address_entry {
> + u8 src_opcode;
> + u8 dst_opcode;
> +};
> +
> +static u8 spi_nor_convert_opcode(u8 opcode,
> + const struct spi_nor_address_entry *entries,
> + size_t num_entries)
> +{
> + int min, max;
> +
> + min = 0;
> + max = num_entries - 1;
> + while (min <= max) {
> + int mid = (min + max) >> 1;
> + const struct spi_nor_address_entry *entry = &entries[mid];
> +
> + if (opcode == entry->src_opcode)
> + return entry->dst_opcode;
> +
> + if (opcode < entry->src_opcode)
> + max = mid - 1;
> + else
> + min = mid + 1;
> + }
> +
> + /* No conversion found */
> + return opcode;
> +}
> +
> +static u8 spi_nor_3to4_opcode(u8 opcode)
> +{
> + /* MUST be sorted by 3byte opcode */
> +#define ENTRY_3TO4(_opcode) { _opcode, _opcode##_4B }
> + static const struct spi_nor_address_entry spi_nor_3to4_table[] = {
> + ENTRY_3TO4(SPINOR_OP_PP), /* 0x02 */
> + ENTRY_3TO4(SPINOR_OP_READ), /* 0x03 */
> + ENTRY_3TO4(SPINOR_OP_READ_FAST), /* 0x0b */
> + ENTRY_3TO4(SPINOR_OP_BE_4K), /* 0x20 */
> + ENTRY_3TO4(SPINOR_OP_PP_1_1_4), /* 0x32 */
> + ENTRY_3TO4(SPINOR_OP_PP_1_4_4), /* 0x38 */
> + ENTRY_3TO4(SPINOR_OP_READ_1_1_2), /* 0x3b */
> + ENTRY_3TO4(SPINOR_OP_BE_32K), /* 0x52 */
> + ENTRY_3TO4(SPINOR_OP_READ_1_1_4), /* 0x6b */
> + ENTRY_3TO4(SPINOR_OP_READ_1_2_2), /* 0xbb */
> + ENTRY_3TO4(SPINOR_OP_SE), /* 0xd8 */
> + ENTRY_3TO4(SPINOR_OP_READ_1_4_4), /* 0xeb */
> + };
> +#undef ENTRY_3TO4
> +
> + return spi_nor_convert_opcode(opcode, spi_nor_3to4_table,
> + ARRAY_SIZE(spi_nor_3to4_table));
> +}
> +
> +static void spi_nor_set_4byte_opcodes(struct spi_nor *nor,
> + const struct flash_info *info)
> +{
> + /* Do some manufacturer fixups first */
> + switch (JEDEC_MFR(info)) {
> + case SNOR_MFR_SPANSION:
> + /* No small sector erase for 4-byte command set */
> + nor->erase_opcode = SPINOR_OP_SE;
> + nor->mtd.erasesize = info->sector_size;
> + break;
> +
> + default:
> + break;
> + }
> +
> + nor->read_opcode = spi_nor_3to4_opcode(nor->read_opcode);
> + nor->program_opcode = spi_nor_3to4_opcode(nor->program_opcode);
> + nor->erase_opcode = spi_nor_3to4_opcode(nor->erase_opcode);
> +}
> +
> /* Enable/disable 4-byte addressing mode. */
> static inline int set_4byte(struct spi_nor *nor, const struct flash_info *info,
> int enable)
> @@ -1476,27 +1555,10 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode)
> 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) {
> - /* Dedicated 4-byte command set */
> - switch (nor->flash_read) {
> - case SPI_NOR_QUAD:
> - nor->read_opcode = SPINOR_OP_READ4_1_1_4;
> - break;
> - case SPI_NOR_DUAL:
> - nor->read_opcode = SPINOR_OP_READ4_1_1_2;
> - break;
> - case SPI_NOR_FAST:
> - nor->read_opcode = SPINOR_OP_READ4_FAST;
> - break;
> - case SPI_NOR_NORMAL:
> - nor->read_opcode = SPINOR_OP_READ4;
> - break;
> - }
> - nor->program_opcode = SPINOR_OP_PP_4B;
> - /* No small sector erase for 4-byte command set */
> - nor->erase_opcode = SPINOR_OP_SE_4B;
> - mtd->erasesize = info->sector_size;
> - } else
> + if (JEDEC_MFR(info) == SNOR_MFR_SPANSION ||
> + info->flags & SPI_NOR_4B_OPCODES)
> + spi_nor_set_4byte_opcodes(nor, info);
> + else
> set_4byte(nor, info, 1);
> } else {
> nor->addr_width = 3;
> diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
> index c425c7b4c2a0..8b02fd7864d0 100644
> --- a/include/linux/mtd/spi-nor.h
> +++ b/include/linux/mtd/spi-nor.h
> @@ -43,9 +43,13 @@
> #define SPINOR_OP_WRSR 0x01 /* Write status register 1 byte */
> #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 SPI) */
> -#define SPINOR_OP_READ_1_1_4 0x6b /* Read data bytes (Quad SPI) */
> +#define SPINOR_OP_READ_1_1_2 0x3b /* Read data bytes (Dual Output SPI) */
> +#define SPINOR_OP_READ_1_2_2 0xbb /* Read data bytes (Dual I/O SPI) */
> +#define SPINOR_OP_READ_1_1_4 0x6b /* Read data bytes (Quad Output SPI) */
> +#define SPINOR_OP_READ_1_4_4 0xeb /* Read data bytes (Quad I/O SPI) */
> #define SPINOR_OP_PP 0x02 /* Page program (up to 256 bytes) */
> +#define SPINOR_OP_PP_1_1_4 0x32 /* Quad page program */
> +#define SPINOR_OP_PP_1_4_4 0x38 /* Quad page program */
> #define SPINOR_OP_BE_4K 0x20 /* Erase 4KiB block */
> #define SPINOR_OP_BE_4K_PMC 0xd7 /* Erase 4KiB block on PMC chips */
> #define SPINOR_OP_BE_32K 0x52 /* Erase 32KiB block */
> @@ -56,11 +60,17 @@
> #define SPINOR_OP_RDFSR 0x70 /* Read flag status register */
>
> /* 4-byte address opcodes - used on Spansion and some Macronix flashes. */
> -#define SPINOR_OP_READ4 0x13 /* Read data bytes (low frequency) */
> -#define SPINOR_OP_READ4_FAST 0x0c /* Read data bytes (high frequency) */
> -#define SPINOR_OP_READ4_1_1_2 0x3c /* Read data bytes (Dual SPI) */
> -#define SPINOR_OP_READ4_1_1_4 0x6c /* Read data bytes (Quad SPI) */
> +#define SPINOR_OP_READ_4B 0x13 /* Read data bytes (low frequency) */
> +#define SPINOR_OP_READ_FAST_4B 0x0c /* Read data bytes (high frequency) */
> +#define SPINOR_OP_READ_1_1_2_4B 0x3c /* Read data bytes (Dual Output SPI) */
> +#define SPINOR_OP_READ_1_2_2_4B 0xbc /* Read data bytes (Dual I/O SPI) */
> +#define SPINOR_OP_READ_1_1_4_4B 0x6c /* Read data bytes (Quad Output SPI) */
> +#define SPINOR_OP_READ_1_4_4_4B 0xec /* Read data bytes (Quad I/O SPI) */
> #define SPINOR_OP_PP_4B 0x12 /* Page program (up to 256 bytes) */
> +#define SPINOR_OP_PP_1_1_4_4B 0x34 /* Quad page program */
> +#define SPINOR_OP_PP_1_4_4_4B 0x3e /* Quad page program */
> +#define SPINOR_OP_BE_4K_4B 0x21 /* Erase 4KiB block */
> +#define SPINOR_OP_BE_32K_4B 0x5c /* Erase 32KiB block */
> #define SPINOR_OP_SE_4B 0xdc /* Sector erase (usually 64KiB) */
>
> /* Used for SST flashes only. */
>

--
Regards
Vignesh