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Date: Sun, 26 Apr 2020 00:36:59 +0530 From: Syed Nayyar Waris <syednwaris@...il.com> To: akpm@...ux-foundation.org Cc: andriy.shevchenko@...ux.intel.com, vilhelm.gray@...il.com, linus.walleij@...aro.org, bgolaszewski@...libre.com, michal.simek@...inx.com, linux-gpio@...r.kernel.org, linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org Subject: [PATCH v2 6/6] gpio: xilinx: Utilize for_each_set_clump macro This patch reimplements the xgpio_set_multiple function in drivers/gpio/gpio-xilinx.c to use the new for_each_set_clump macro. Instead of looping for each bit in xgpio_set_multiple function, now we can check each channel at a time and save cycles. Cc: Linus Walleij <linus.walleij@...aro.org> Cc: Bartosz Golaszewski <bgolaszewski@...libre.com> Cc: Michal Simek <michal.simek@...inx.com> Signed-off-by: Syed Nayyar Waris <syednwaris@...il.com> Signed-off-by: William Breathitt Gray <vilhelm.gray@...il.com> --- Changes in v2: - No change. drivers/gpio/gpio-xilinx.c | 64 ++++++++++++++++++++++++---------------------- 1 file changed, 34 insertions(+), 30 deletions(-) diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c index 67f9f82..428207f 100644 --- a/drivers/gpio/gpio-xilinx.c +++ b/drivers/gpio/gpio-xilinx.c @@ -136,39 +136,43 @@ static void xgpio_set(struct gpio_chip *gc, unsigned int gpio, int val) static void xgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask, unsigned long *bits) { - unsigned long flags; + unsigned long flags[2]; 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); - } + u32 *const state = chip->gpio_state; + unsigned int *const width = chip->gpio_width; + const unsigned long state_size = BITS_PER_TYPE(*state); + unsigned long offset, clump; + size_t index; + +#define TOTAL_BITS BITS_PER_TYPE(chip->gpio_state) + DECLARE_BITMAP(old, TOTAL_BITS); + DECLARE_BITMAP(new, TOTAL_BITS); + DECLARE_BITMAP(changed, TOTAL_BITS); + + spin_lock_irqsave(&chip->gpio_lock[0], flags[0]); + spin_lock_irqsave(&chip->gpio_lock[1], flags[1]); + + bitmap_set_value(old, state[0], 0, width[0]); + bitmap_set_value(old, state[1], width[0], width[1]); + bitmap_replace(new, old, bits, mask, gc->ngpio); + + bitmap_set_value(old, state[0], 0, state_size); + bitmap_set_value(old, state[1], state_size, state_size); + state[0] = bitmap_get_value(new, 0, width[0]); + state[1] = bitmap_get_value(new, width[0], width[1]); + bitmap_set_value(new, state[0], 0, state_size); + bitmap_set_value(new, state[1], state_size, state_size); + bitmap_xor(changed, old, new, TOTAL_BITS); + + for_each_set_clump(offset, clump, changed, TOTAL_BITS, state_size) { + index = offset / state_size; + xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET + + index * XGPIO_CHANNEL_OFFSET, + state[index]); } - xgpio_writereg(chip->regs + XGPIO_DATA_OFFSET + - index * XGPIO_CHANNEL_OFFSET, chip->gpio_state[index]); - - spin_unlock_irqrestore(&chip->gpio_lock[index], flags); + spin_unlock_irqrestore(&chip->gpio_lock[1], flags[1]); + spin_unlock_irqrestore(&chip->gpio_lock[0], flags[0]); } /** -- 2.7.4
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