Re: [RFC RFT PATCH 0/4] gpiolib: speed up GPIO array processing
Hi Linus, On Wednesday, August 29, 2018 11:06:21 AM CEST Linus Walleij wrote: > On Tue, Aug 21, 2018 at 1:42 AM Janusz Krzysztofik wrote: > > > This series is a follow up of the former "mtd: rawnand: ams-delta: Use > > gpio-omap accessors for data I/O" which already contained some changes > > to gpiolib. Those previous attempts were commented by Borris Brezillon > > who suggested using GPIO API modified to accept bitmaps, and by Linus > > Walleij who suggested still more great ideas for further immprovement > > of the proposed API changes - thanks! > > > > The goal is to boost performans of get/set array functions while > > processing GPIO arrays which represent pins of a signle chip in > > hardware order. If resulting performance is close to PIO, GPIO API > > can be used for data I/O without much loss of speed. > > Hands down, this is a very pretty patch set. I'm a big fan already. > > This is mainly because it fulfills the requirement for libraries > to be narrow and deep, which is what we want. > This refers to John Ousterhouts software design philosophy, > here is a great lecture if you haven't seen it already: > https://www.youtube.com/watch?v=bmSAYlu0NcY > > Let's get this into v1 and get some testing and merge it for v4.20 > ASAP Please hold on for a while, I'm going to resubmit soon, with the comment from Peter Rosin on i2c-mux-gpio addressed and the error discovered by Miguel Ojeda in hd44780 fixed. Thanks, Janusz > so we get some proper testing before the v4.20 merge > window. It would be excellent if some of the current users of > the array API could provide tested-by's or at least ACKs. > > For example ts-nbus.c must be a big benefactor. > > Yours, > Linus Walleij > ___ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
Re: [RFC RFT PATCH 0/4] gpiolib: speed up GPIO array processing
On 21 August 2018 at 01:43, Janusz Krzysztofik wrote: > > This series is a follow up of the former "mtd: rawnand: ams-delta: Use > gpio-omap accessors for data I/O" which already contained some changes > to gpiolib. Those previous attempts were commented by Borris Brezillon > who suggested using GPIO API modified to accept bitmaps, and by Linus > Walleij who suggested still more great ideas for further immprovement > of the proposed API changes - thanks! > > The goal is to boost performans of get/set array functions while > processing GPIO arrays which represent pins of a signle chip in > hardware order. If resulting performance is close to PIO, GPIO API > can be used for data I/O without much loss of speed. > > Created and tested on a low end Amstrad Delta board with NAND driver > updated to use GPIO API for data I/O. Performance degrade compared to > PIO is much better than before the optimization but still not quite > satisfactory. > > > Janusz Krzysztofik (4): > gpiolib: Pass bitmaps, not integer arrays, to get/set array > gpiolib: Identify arrays matching GPIO hardware > gpiolib: Pass array info to get/set array functions > gpiolib: Implement fast processing path in get/set array > > > Documentation/driver-api/gpio/board.rst | 15 + > Documentation/driver-api/gpio/consumer.rst | 48 +++- > drivers/auxdisplay/hd44780.c| 64 +++--- > drivers/bus/ts-nbus.c | 25 -- > drivers/gpio/gpio-max3191x.c| 23 +- > drivers/gpio/gpiolib.c | 279 > ++-- > drivers/gpio/gpiolib.h | 15 + > drivers/i2c/muxes/i2c-mux-gpio.c|5 > drivers/mmc/core/pwrseq_simple.c| 15 - > drivers/mux/gpio.c |7 > drivers/net/phy/mdio-mux-gpio.c |5 > drivers/pcmcia/soc_common.c | 14 - > drivers/phy/motorola/phy-mapphone-mdm6600.c | 21 +- > drivers/staging/iio/adc/ad7606.c| 12 - > drivers/tty/serial/serial_mctrl_gpio.c |9 > include/linux/gpio/consumer.h | 35 ++- > 16 files changed, 410 insertions(+), 182 deletions(-) > For the mmc related changes: Acked-by: Ulf Hansson Kind regards Uffe ___ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
Re: [RFC RFT PATCH 0/4] gpiolib: speed up GPIO array processing
On Tue, Aug 21, 2018 at 1:42 AM Janusz Krzysztofik wrote: > This series is a follow up of the former "mtd: rawnand: ams-delta: Use > gpio-omap accessors for data I/O" which already contained some changes > to gpiolib. Those previous attempts were commented by Borris Brezillon > who suggested using GPIO API modified to accept bitmaps, and by Linus > Walleij who suggested still more great ideas for further immprovement > of the proposed API changes - thanks! > > The goal is to boost performans of get/set array functions while > processing GPIO arrays which represent pins of a signle chip in > hardware order. If resulting performance is close to PIO, GPIO API > can be used for data I/O without much loss of speed. Hands down, this is a very pretty patch set. I'm a big fan already. This is mainly because it fulfills the requirement for libraries to be narrow and deep, which is what we want. This refers to John Ousterhouts software design philosophy, here is a great lecture if you haven't seen it already: https://www.youtube.com/watch?v=bmSAYlu0NcY Let's get this into v1 and get some testing and merge it for v4.20 ASAP so we get some proper testing before the v4.20 merge window. It would be excellent if some of the current users of the array API could provide tested-by's or at least ACKs. For example ts-nbus.c must be a big benefactor. Yours, Linus Walleij ___ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
