clk: meson: Support PLL with fixed fractional denominators

Some PLLS with fractional multipliers have fractional denominators with
fixed values, instead of the previous "(1 << pll-> frc.width)".

Signed-off-by: Chuan Liu <chuan.liu@amlogic.com>
Link: https://lore.kernel.org/r/20240909-fix_clk-v3-1-a6d8f6333c04@amlogic.com
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>

drivers/clk/meson/clk-pll.c

@@ -57,12 +57,13 @@ static unsigned long __pll_params_to_rate(unsigned long parent_rate,
 					  struct meson_clk_pll_data *pll)
 {
 	u64 rate = (u64)parent_rate * m;
+	unsigned int frac_max = pll->frac_max ? pll->frac_max :
+						(1 << pll->frac.width);
 
 	if (frac && MESON_PARM_APPLICABLE(&pll->frac)) {
 		u64 frac_rate = (u64)parent_rate * frac;
 
-		rate += DIV_ROUND_UP_ULL(frac_rate,
-					 (1 << pll->frac.width));
+		rate += DIV_ROUND_UP_ULL(frac_rate, frac_max);
 	}
 
 	return DIV_ROUND_UP_ULL(rate, n);
@@ -100,7 +101,8 @@ static unsigned int __pll_params_with_frac(unsigned long rate,
 					   unsigned int n,
 					   struct meson_clk_pll_data *pll)
 {
-	unsigned int frac_max = (1 << pll->frac.width);
+	unsigned int frac_max = pll->frac_max ? pll->frac_max :
+						(1 << pll->frac.width);
 	u64 val = (u64)rate * n;
 
 	/* Bail out if we are already over the requested rate */

drivers/clk/meson/clk-pll.h

@@ -43,6 +43,7 @@ struct meson_clk_pll_data {
 	unsigned int init_count;
 	const struct pll_params_table *table;
 	const struct pll_mult_range *range;
+	unsigned int frac_max;
 	u8 flags;
 };