Hi Patrice, On Mon, 31 Jan 2022 at 09:14, Patrice CHOTARD <[email protected]> wrote: > > Hi Simon > > On 1/21/22 16:20, Simon Glass wrote: > > Hi Patrice, > > > > On Wed, 12 Jan 2022 at 03:59, Patrice Chotard > > <[email protected]> wrote: > >> > >> Add spi_flash_probe_bus_cs() and spi_get_bus_and_cs() new "use_dt" > >> param which allows to select SPI speed and mode from DT or from > >> default value passed in parameters. > >> > >> 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. > >> > >> By adding new parameter "use_dt" to spi_flash_probe_bus_cs() and to > >> spi_get_bus_and_cs(), this allows to force usage of either speed and > >> mode from DT (use_dt = true) or to use speed and mode parameter value. > >> > >> Signed-off-by: Patrice Chotard <[email protected]> > >> Cc: Marek Behun <[email protected]> > >> Cc: Jagan Teki <[email protected]> > >> Cc: Vignesh R <[email protected]> > >> Cc: Joe Hershberger <[email protected]> > >> Cc: Ramon Fried <[email protected]> > >> Cc: Lukasz Majewski <[email protected]> > >> Cc: Marek Vasut <[email protected]> > >> Cc: Wolfgang Denk <[email protected]> > >> Cc: Simon Glass <[email protected]> > >> Cc: Stefan Roese <[email protected]> > >> Cc: "Pali Rohár" <[email protected]> > >> Cc: Konstantin Porotchkin <[email protected]> > >> Cc: Igal Liberman <[email protected]> > >> Cc: Bin Meng <[email protected]> > >> Cc: Pratyush Yadav <[email protected]> > >> Cc: Sean Anderson <[email protected]> > >> Cc: Anji J <[email protected]> > >> Cc: Biwen Li <[email protected]> > >> Cc: Priyanka Jain <[email protected]> > >> Cc: Chaitanya Sakinam <[email protected]> > >> --- > >> > >> board/CZ.NIC/turris_mox/turris_mox.c | 2 +- > >> cmd/sf.c | 5 ++++- > >> cmd/spi.c | 2 +- > >> drivers/mtd/spi/sf-uclass.c | 8 ++++---- > >> drivers/net/fm/fm.c | 5 +++-- > >> drivers/net/pfe_eth/pfe_firmware.c | 2 +- > >> drivers/net/sni_netsec.c | 3 ++- > >> drivers/spi/spi-uclass.c | 8 ++++---- > >> drivers/usb/gadget/max3420_udc.c | 2 +- > >> env/sf.c | 2 +- > >> include/spi.h | 9 +++++---- > >> include/spi_flash.h | 2 +- > >> test/dm/spi.c | 15 ++++++++------- > >> 13 files changed, 36 insertions(+), 29 deletions(-) > > > > I think this is a good idea, but should use a separate function name > > instead of adding an argument, since it doesn't make sense to pass > > parameters that are ignored. > > I am confused, do you mean duplicate spi_flash_probe_bus_cs() in another > function spi_flash_probe_bus_cs_default() > for example ? > In the former spi_get_bus_and_cs() will be called with "use_dt" param set to > true and in the latter > "use_dt" param will be set to false ? > > spi_flash_probe_bus_cs() => spi_get_bus_and_cs(.., true , ...) > spi_flash_probe_bus_cs_default() => spi_get_bus_and_cs(.., false, ...)
Maybe rename spi_get_bus_and_cs() to _spi_get_bus_and_cs() ? It seems to me that if use_dt is provided, we should actually be using DT and not calling this function at all. We should just be able to probe the device and the right things should happen. If we must use the bus and cs numbers, and use_dt is true, then we should not need to specify the mode, speed, etc. So the args to that function should be different. So I believe the two functions should have quite different args. Perhaps the core part of spi_get_bus_and_cs() could be split out? I just feel there are way too many arguments and adding an argument that cancels out some of the others just makes a confusing mess. > > Thanks > Patrice > > > > Also we should probably have devicetree as the default (the base function > > name). > > See that also ^ Regards, Simon
