Allow flashes to specify a hook to enable octal DTR mode. Use this hook whenever possible to get optimal transfer speeds.
Signed-off-by: Pratyush Yadav p.yadav@ti.com --- drivers/mtd/spi/spi-nor-core.c | 31 +++++++++++++++++++++++++++++++ include/linux/mtd/spi-nor.h | 2 ++ 2 files changed, 33 insertions(+)
diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c index 9361b5c121..5b995cda3f 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -2760,10 +2760,41 @@ static int spi_nor_setup(struct spi_nor *nor, const struct flash_info *info, return nor->setup(nor, info, params, hwcaps); }
+/** spi_nor_octal_dtr_enable() - enable Octal DTR I/O if needed + * @nor: pointer to a 'struct spi_nor' + * + * Return: 0 on success, -errno otherwise. + */ +static int spi_nor_octal_dtr_enable(struct spi_nor *nor) +{ + int ret; + + if (!nor->octal_dtr_enable) + return 0; + + if (!(spi_nor_get_protocol_width(nor->read_proto) == 8 || + spi_nor_get_protocol_width(nor->write_proto) == 8)) + return 0; + + ret = nor->octal_dtr_enable(nor); + if (ret) + return ret; + + nor->reg_proto = SNOR_PROTO_8_8_8_DTR; + + return 0; +} + static int spi_nor_init(struct spi_nor *nor) { int err;
+ err = spi_nor_octal_dtr_enable(nor); + if (err) { + dev_dbg(nor->dev, "Octal DTR mode not supported\n"); + return err; + } + /* * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up * with the software protection bits set diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index 4b3b81ce67..defd0d2d3d 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -468,6 +468,7 @@ struct flash_info; * @flash_is_locked: [FLASH-SPECIFIC] check if a region of the SPI NOR is * @quad_enable: [FLASH-SPECIFIC] enables SPI NOR quad mode * completely locked + * @octal_dtr_enable: [FLASH-SPECIFIC] enables SPI NOR octal DTR mode. * @priv: the private data */ struct spi_nor { @@ -515,6 +516,7 @@ struct spi_nor { int (*flash_unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len); int (*flash_is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len); int (*quad_enable)(struct spi_nor *nor); + int (*octal_dtr_enable)(struct spi_nor *nor);
void *priv; /* Compatibility for spi_flash, remove once sf layer is merged with mtd */