[PATCH v4 0/3] spi: spi_flash_probe_bus_cs() rely on DT for spi speed and mode

[Patrice CHOTARD]

Hi Jagan

Could you have a look at this series ?
It would be great if this series can be merged in the v2022.07

Thanks

Patrice


On 3/30/22 09:33, Patrice Chotard wrote:
> Since commit e2e95e5e2542 ("spi: Update speed/mode on change")
> when calling "sf probe" or "env save" on SPI flash,
> spi_set_speed_mode() is called twice.
>
> spi_get_bus_and_cs()
>        |--> spi_claim_bus()
>        |       |--> spi_set_speed_mode(speed and mode from DT)
>        ...
>        |--> spi_set_speed_mode(default speed and mode value)
>
> The first spi_set_speed_mode() call is done with speed and mode
> values from DT, whereas the second call is done with speed
> and mode set to default value (speed is set to CONFIG_SF_DEFAULT_SPEED)
>
> This is an issue because SPI flash performance are impacted by
> using default speed which can be lower than the one defined in DT.
>
> One solution is to set CONFIG_SF_DEFAULT_SPEED to the speed defined
> in DT, but we loose flexibility offered by DT.
>
> Another issue can be encountered with 2 SPI flashes using 2 different
> speeds. In this specific case usage of CONFIG_SF_DEFAULT_SPEED is not
> flexible compared to get the 2 different speeds from DT.
>
>
> Changes in v4:
>    - Split previous series in 3 patches
>    - Update commit message with additionnal information
>
> Changes in v3:
>    - Update commit header to reflect what the patch really do.
>    - Rename legacy spi_get_bus_and_cs() to _spi_get_bus_and_cs().
>    - New spi_get_bus_and_cs() rely on DT for spi speed and mode values.
>    - spi_flash_probe_bus_cs() rely also on DT for spi and mode values.
>
> Changes in v2:
>    - add spi_flash_probe_bus_cs_default() which calls spi_get_bus_and_cs()
>      with "use_dt" param set to true, whereas spi_flash_probe_bus_cs() calls
>      spi_get_bus_and_cs() with "use_dt" param set to true.
>
> Patrice Chotard (3):
>    spi: spi-uclass: Add new spi_get_bus_and_cs() implementation
>    spi: spi_flash_probe_bus_cs() rely on DT for spi speed and mode
>    test: dm: spi: Replace _spi_get_bus_and_cs() by spi_get_bus_and_cs()
>      in some case
>
>   board/CZ.NIC/turris_mox/turris_mox.c |  6 +--
>   cmd/sf.c                             | 15 +++++--
>   cmd/spi.c                            |  4 +-
>   drivers/mtd/spi/sf-uclass.c          | 33 +++++++-------
>   drivers/net/fm/fm.c                  |  4 +-
>   drivers/net/pfe_eth/pfe_firmware.c   | 19 ++------
>   drivers/net/sni_netsec.c             |  6 +--
>   drivers/spi/spi-uclass.c             | 66 +++++++++++++++++++++++++---
>   drivers/usb/gadget/max3420_udc.c     |  4 +-
>   env/sf.c                             |  1 -
>   include/spi.h                        | 19 +++++++-
>   include/spi_flash.h                  |  1 -
>   test/dm/spi.c                        | 33 +++++++-------
>   13 files changed, 137 insertions(+), 74 deletions(-)
>