net: phy: Add LED mode driver for Microsemi PHYs.

LED Mode:
Microsemi PHY support 2 LEDs (LED[0] and LED[1]) to display different
status information that can be selected by setting LED mode.

LED Mode parameter (vsc8531, led-0-mode) and (vsc8531, led-1-mode) get
from Device Tree.

Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

path: root/tools/build/feature/test-sync-compare-and-swap.c

#include <stdint.h>

volatile uint64_t x;

int main(int argc, char *argv[])
{
	uint64_t old, new = argc;

	argv = argv;
	do {
		old = __sync_val_compare_and_swap(&x, 0, 0);
	} while (!__sync_bool_compare_and_swap(&x, old, new));
	return old == new;
}