Re: [PATCH v3 3/3] gpio: xilinx: Utilize generic bitmap_get_value and _set_value

From: Bartosz Golaszewski
Date: Fri Mar 26 2021 - 13:28:20 EST


On Mon, Mar 8, 2021 at 8:13 AM Michal Simek <michal.simek@xxxxxxxxxx> wrote:
>
>
>
> On 3/6/21 3:06 PM, Syed Nayyar Waris wrote:
> > This patch reimplements the xgpio_set_multiple() function in
> > drivers/gpio/gpio-xilinx.c to use the new generic functions:
> > bitmap_get_value() and bitmap_set_value(). The code is now simpler
> > to read and understand. Moreover, instead of looping for each bit
> > in xgpio_set_multiple() function, now we can check each channel at
> > a time and save cycles.
> >
> > Cc: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
> > Cc: Michal Simek <michal.simek@xxxxxxxxxx>
> > Signed-off-by: Syed Nayyar Waris <syednwaris@xxxxxxxxx>
> > Acked-by: William Breathitt Gray <vilhelm.gray@xxxxxxxxx>
> > ---
> > drivers/gpio/gpio-xilinx.c | 63 +++++++++++++++++++-------------------
> > 1 file changed, 32 insertions(+), 31 deletions(-)
> >
> > diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
> > index be539381fd82..8445e69cf37b 100644
> > --- a/drivers/gpio/gpio-xilinx.c
> > +++ b/drivers/gpio/gpio-xilinx.c
> > @@ -15,6 +15,7 @@
> > #include <linux/of_device.h>
> > #include <linux/of_platform.h>
> > #include <linux/slab.h>
> > +#include "gpiolib.h"
> >
> > /* Register Offset Definitions */
> > #define XGPIO_DATA_OFFSET (0x0) /* Data register */
> > @@ -141,37 +142,37 @@ static void xgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
> > {
> > unsigned long flags;
> > struct xgpio_instance *chip = gpiochip_get_data(gc);
> > - int index = xgpio_index(chip, 0);
> > - int offset, i;
> > -
> > - spin_lock_irqsave(&chip->gpio_lock[index], flags);
> > -
> > - /* Write to GPIO signals */
> > - for (i = 0; i < gc->ngpio; i++) {
> > - if (*mask == 0)
> > - break;
> > - /* Once finished with an index write it out to the register */
> > - if (index != xgpio_index(chip, i)) {
> > - xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
> > - index * XGPIO_CHANNEL_OFFSET,
> > - chip->gpio_state[index]);
> > - spin_unlock_irqrestore(&chip->gpio_lock[index], flags);
> > - index = xgpio_index(chip, i);
> > - spin_lock_irqsave(&chip->gpio_lock[index], flags);
> > - }
> > - if (__test_and_clear_bit(i, mask)) {
> > - offset = xgpio_offset(chip, i);
> > - if (test_bit(i, bits))
> > - chip->gpio_state[index] |= BIT(offset);
> > - else
> > - chip->gpio_state[index] &= ~BIT(offset);
> > - }
> > - }
> > -
> > - xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
> > - index * XGPIO_CHANNEL_OFFSET, chip->gpio_state[index]);
> > -
> > - spin_unlock_irqrestore(&chip->gpio_lock[index], flags);
> > + u32 *const state = chip->gpio_state;
> > + unsigned int *const width = chip->gpio_width;
> > +
> > + DECLARE_BITMAP(old, 64);
> > + DECLARE_BITMAP(new, 64);
> > + DECLARE_BITMAP(changed, 64);
> > +
> > + spin_lock_irqsave(&chip->gpio_lock[0], flags);
> > + spin_lock(&chip->gpio_lock[1]);
> > +
> > + bitmap_set_value(old, 64, state[0], width[0], 0);
> > + bitmap_set_value(old, 64, state[1], width[1], width[0]);
> > + bitmap_replace(new, old, bits, mask, gc->ngpio);
> > +
> > + bitmap_set_value(old, 64, state[0], 32, 0);
> > + bitmap_set_value(old, 64, state[1], 32, 32);
> > + state[0] = bitmap_get_value(new, 0, width[0]);
> > + state[1] = bitmap_get_value(new, width[0], width[1]);
> > + bitmap_set_value(new, 64, state[0], 32, 0);
> > + bitmap_set_value(new, 64, state[1], 32, 32);
> > + bitmap_xor(changed, old, new, 64);
> > +
> > + if (((u32 *)changed)[0])
> > + xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET,
> > + state[0]);
> > + if (((u32 *)changed)[1])
> > + xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET +
> > + XGPIO_CHANNEL_OFFSET, state[1]);
> > +
> > + spin_unlock(&chip->gpio_lock[1]);
> > + spin_unlock_irqrestore(&chip->gpio_lock[0], flags);
> > }
> >
> > /**
> >
>
> Srinivas N: Can you please test this code?
>
> Thanks,
> Michal

Hey, any chance of getting that Tested-by?

Bart