From patchwork Fri Jun 5 12:44:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pratyush Yadav X-Patchwork-Id: 241825 List-Id: U-Boot discussion From: p.yadav at ti.com (Pratyush Yadav) Date: Fri, 5 Jun 2020 18:14:54 +0530 Subject: [PATCH v6 15/21] mtd: spi-nor-core: Enable octal DTR mode when possible In-Reply-To: <20200605124500.17867-1-p.yadav@ti.com> References: <20200605124500.17867-1-p.yadav@ti.com> Message-ID: <20200605124500.17867-16-p.yadav@ti.com> 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 --- 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 743a07c5ec..95743c3fb6 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -2882,10 +2882,41 @@ static int spi_nor_setup(struct spi_nor *nor, const struct flash_info *info, return nor->setup(nor, info, params); } +/** 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 (!(nor->read_proto == SNOR_PROTO_8_8_8_DTR && + nor->write_proto == SNOR_PROTO_8_8_8_DTR)) + 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 7054408e97..c035fed741 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -475,6 +475,7 @@ 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 { @@ -522,6 +523,7 @@ 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 */