Re: [PATCH] mtd: revert "spi-nor: intel: provide a range for poll_timout"

Mika Westerberg
2020-06-11T10:39:59Z

On Wed, Jun 10, 2020 at 10:46:49PM +0000, Luis Alberto Herrera wrote:
> This change reverts aba3a882a178: "mtd: spi-nor: intel: provide a range
> for poll_timout". That change introduces a performance regression when
> reading sequentially from flash. Logging calls to intel_spi_read without
> this change we get:
>
> Start MTD read
> [ 20.045527] intel_spi_read(from=1800000, len=400000)
> [ 20.045527] intel_spi_read(from=1800000, len=400000)
> [ 282.199274] intel_spi_read(from=1c00000, len=400000)
> [ 282.199274] intel_spi_read(from=1c00000, len=400000)
> [ 544.351528] intel_spi_read(from=2000000, len=400000)
> [ 544.351528] intel_spi_read(from=2000000, len=400000)
> End MTD read
>
> With this change:
>
> Start MTD read
> [ 21.942922] intel_spi_read(from=1c00000, len=400000)
> [ 21.942922] intel_spi_read(from=1c00000, len=400000)
> [ 23.784058] intel_spi_read(from=2000000, len=400000)
> [ 23.784058] intel_spi_read(from=2000000, len=400000)
> [ 25.625006] intel_spi_read(from=2400000, len=400000)
> [ 25.625006] intel_spi_read(from=2400000, len=400000)
> End MTD read
>
> Signed-off-by: Luis Alberto Herrera <luisalberto@google.com>

Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>