static void clk_fd_general_approximation(struct clk_hw *hw, unsigned long rate,
					 unsigned long *parent_rate,
					 unsigned long *m, unsigned long *n)
{
	struct clk_fractional_divider *fd = to_clk_fd(hw);
	unsigned long scale;

	/*
	 * Get rate closer to *parent_rate to guarantee there is no overflow
	 * for m and n. In the result it will be the nearest rate left shifted
	 * by (scale - fd->nwidth) bits.
	 */
	scale = fls_long((unsigned long)udiv64(*parent_rate, rate) - 1);
	if (scale > fd->nwidth)
		rate <<= scale - fd->nwidth;

	rational_best_approximation(rate, *parent_rate,
			GENMASK(fd->mwidth - 1, 0), GENMASK(fd->nwidth - 1, 0),
			m, n);
}
Example #2
0
static inline int eirr_to_irq(unsigned long eirr)
{
	int bit = fls_long(eirr);
	return (BITS_PER_LONG - bit) + TIMER_IRQ;
}