clk: Compute masks for fractional_divider clk when needed.

There is no real need to pre-compute mmask and nmask when handling
fractional_divider clk.

They can be computed when needed.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/0fd6357242c974259c9e034c6e28a0391c480bf0.1680423909.git.christophe.jaillet@wanadoo.fr
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

Author: tititiou36

drivers/clk/clk-fractional-divider.c

@@ -71,6 +71,7 @@ static void clk_fd_get_div(struct clk_hw *hw, struct u32_fract *fract)
 	struct clk_fractional_divider *fd = to_clk_fd(hw);
 	unsigned long flags = 0;
 	unsigned long m, n;
+	u32 mmask, nmask;
 	u32 val;
 
 	if (fd->lock)
@@ -85,8 +86,11 @@ static void clk_fd_get_div(struct clk_hw *hw, struct u32_fract *fract)
 	else
 		__release(fd->lock);
 
-	m = (val & fd->mmask) >> fd->mshift;
-	n = (val & fd->nmask) >> fd->nshift;
+	mmask = GENMASK(fd->mwidth - 1, 0) << fd->mshift;
+	nmask = GENMASK(fd->nwidth - 1, 0) << fd->nshift;
+
+	m = (val & mmask) >> fd->mshift;
+	n = (val & nmask) >> fd->nshift;
 
 	if (fd->flags & CLK_FRAC_DIVIDER_ZERO_BASED) {
 		m++;
@@ -166,6 +170,7 @@ static int clk_fd_set_rate(struct clk_hw *hw, unsigned long rate,
 	struct clk_fractional_divider *fd = to_clk_fd(hw);
 	unsigned long flags = 0;
 	unsigned long m, n;
+	u32 mmask, nmask;
 	u32 val;
 
 	rational_best_approximation(rate, parent_rate,
@@ -182,8 +187,11 @@ static int clk_fd_set_rate(struct clk_hw *hw, unsigned long rate,
 	else
 		__acquire(fd->lock);
 
+	mmask = GENMASK(fd->mwidth - 1, 0) << fd->mshift;
+	nmask = GENMASK(fd->nwidth - 1, 0) << fd->nshift;
+
 	val = clk_fd_readl(fd);
-	val &= ~(fd->mmask | fd->nmask);
+	val &= ~(mmask | nmask);
 	val |= (m << fd->mshift) | (n << fd->nshift);
 	clk_fd_writel(fd, val);
 
@@ -260,10 +268,8 @@ struct clk_hw *clk_hw_register_fractional_divider(struct device *dev,
 	fd->reg = reg;
 	fd->mshift = mshift;
 	fd->mwidth = mwidth;
-	fd->mmask = GENMASK(mwidth - 1, 0) << mshift;
 	fd->nshift = nshift;
 	fd->nwidth = nwidth;
-	fd->nmask = GENMASK(nwidth - 1, 0) << nshift;
 	fd->flags = clk_divider_flags;
 	fd->lock = lock;
 	fd->hw.init = &init;