Message ID | 20201201102711.8727-3-p.yadav@ti.com |
---|---|
State | Accepted |
Delegated to: | Vignesh R |
Headers | show |
Series | mtd: Make sure UBIFS does not do multi-pass page programming on flashes that don't support it | expand |
Hi Pratyush, On 12/1/20 3:57 PM, Pratyush Yadav wrote: > Some flashes like the Cypress S28 family use ECC. Under this ECC scheme, > multi-pass writes to an ECC block is not allowed. In other words, once > data is programmed to an ECC block, it can't be programmed again without > erasing it first. > > Upper layers like file systems need to be given this information so they > do not cause error conditions on the flash by attempting multi-pass > programming. This can be done by setting 'writesize' in 'struct > mtd_info'. > > Set the default to 1 but allow flashes to modify it in fixup hooks. If > more flashes show up with this constraint in the future it might be > worth it to add it to 'struct flash_info', but for now increasing its > size is not worth it. > > Signed-off-by: Pratyush Yadav <p.yadav@ti.com> > Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com> > --- > Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git spi-nor/next, thanks! [2/3] mtd: spi-nor: core: Allow flashes to specify MTD writesize https://git.kernel.org/mtd/c/afd473e858 Regards Vignesh
diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c index 5bee7c8da4dc..e77b38de47ed 100644 --- a/drivers/mtd/spi-nor/core.c +++ b/drivers/mtd/spi-nor/core.c @@ -2885,6 +2885,7 @@ static void spi_nor_info_init_params(struct spi_nor *nor) nor->flags |= SNOR_F_HAS_16BIT_SR; /* Set SPI NOR sizes. */ + params->writesize = 1; params->size = (u64)info->sector_size * info->n_sectors; params->page_size = info->page_size; @@ -3430,7 +3431,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, mtd->name = dev_name(dev); mtd->priv = nor; mtd->type = MTD_NORFLASH; - mtd->writesize = 1; + mtd->writesize = nor->params->writesize; mtd->flags = MTD_CAP_NORFLASH; mtd->size = nor->params->size; mtd->_erase = spi_nor_erase; diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h index 0a775a7b5606..5ab3f269a23c 100644 --- a/drivers/mtd/spi-nor/core.h +++ b/drivers/mtd/spi-nor/core.h @@ -193,6 +193,8 @@ struct spi_nor_locking_ops { * Serial Flash Discoverable Parameters (SFDP) tables. * * @size: the flash memory density in bytes. + * @writesize Minimal writable flash unit size. Defaults to 1. Set to + * ECC unit size for ECC-ed flashes. * @page_size: the page size of the SPI NOR flash memory. * @rdsr_dummy: dummy cycles needed for Read Status Register command. * @rdsr_addr_nbytes: dummy address bytes needed for Read Status Register @@ -219,6 +221,7 @@ struct spi_nor_locking_ops { */ struct spi_nor_flash_parameter { u64 size; + u32 writesize; u32 page_size; u8 rdsr_dummy; u8 rdsr_addr_nbytes;