linux-kernel - [RESEND PATCH v4 2/3] gpio: thunderx: Utilize for_each_set

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Date:   Fri, 2 Apr 2021 22:06:48 +0530
From:   Syed Nayyar Waris <syednwaris@...il.com>
To:     bgolaszewski@...libre.com
Cc:     andriy.shevchenko@...ux.intel.com, vilhelm.gray@...il.com,
        michal.simek@...inx.com, arnd@...db.de, rrichter@...vell.com,
        linus.walleij@...aro.org, bgolaszewski@...libre.com,
        yamada.masahiro@...ionext.com, akpm@...ux-foundation.org,
        rui.zhang@...el.com, daniel.lezcano@...aro.org,
        amit.kucheria@...durent.com, linux-arch@...r.kernel.org,
        linux-gpio@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, linux-pm@...r.kernel.org
Subject: [RESEND PATCH v4 2/3] gpio: thunderx: Utilize for_each_set_nbits
 macro

This patch reimplements the thunderx_gpio_set_multiple function in
drivers/gpio/gpio-thunderx.c to use the new for_each_set_nbits macro.
Instead of looping for each bank in thunderx_gpio_set_multiple
function, now we can skip bank which is not set and save cycles.

Cc: Robert Richter <rrichter@...vell.com>
Cc: Bartosz Golaszewski <bgolaszewski@...libre.com>
Signed-off-by: Syed Nayyar Waris <syednwaris@...il.com>
Acked-by: William Breathitt Gray <vilhelm.gray@...il.com>
---
 drivers/gpio/gpio-thunderx.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/gpio/gpio-thunderx.c b/drivers/gpio/gpio-thunderx.c
index 9f66deab46ea..4349e7393a1d 100644
--- a/drivers/gpio/gpio-thunderx.c
+++ b/drivers/gpio/gpio-thunderx.c
@@ -16,7 +16,7 @@
 #include <linux/pci.h>
 #include <linux/spinlock.h>
 #include <asm-generic/msi.h>
-
+#include "gpiolib.h"
 
 #define GPIO_RX_DAT	0x0
 #define GPIO_TX_SET	0x8
@@ -275,12 +275,15 @@ static void thunderx_gpio_set_multiple(struct gpio_chip *chip,
 				       unsigned long *bits)
 {
 	int bank;
-	u64 set_bits, clear_bits;
+	unsigned long set_bits, clear_bits, gpio_mask;
+	unsigned long offset;
+
 	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
 
-	for (bank = 0; bank <= chip->ngpio / 64; bank++) {
-		set_bits = bits[bank] & mask[bank];
-		clear_bits = ~bits[bank] & mask[bank];
+	for_each_set_nbits(offset, gpio_mask, mask, chip->ngpio, 64) {
+		bank = offset / 64;
+		set_bits = bits[bank] & gpio_mask;
+		clear_bits = ~bits[bank] & gpio_mask;
 		writeq(set_bits, txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_TX_SET);
 		writeq(clear_bits, txgpio->register_base + (bank * GPIO_2ND_BANK) + GPIO_TX_CLR);
 	}
-- 
2.29.0