MLK-20947 clk: imx: update the audio pll rate table on imx8mm

Audio PLL is a frac pll, the config for this PLL should follow
below limitation:
    Fout = ((m + k / 65536) * FIN) / (p * 2^s),
    Fvco = ((m + k / 65536) * FIN) / p
    Fref = FIN / p

    a). 6MHz <= Fref <= 25MHz;
    b). 1 <= p <= 63;
    c). 64 <= m <= 1023;
    d). 0 <= s <= 6;
    e). -32768 <= k <= 32767;

due to the frac part calculation deviation, frac pll 'recalc_rate'
is updated to look up the pll rate from table first.

Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Reviewed-by: Anson Huang <Anson.Huang@nxp.com>

2 files changed, 18 insertions, 3 deletions

diff --git a/drivers/clk/imx/clk-imx8mm.c b/drivers/clk/imx/clk-imx8mm.c
index 3cd9c57ed8b8..5709bfce578c 100644
--- a/drivers/clk/imx/clk-imx8mm.c
+++ b/drivers/clk/imx/clk-imx8mm.c
@@ -77,8 +77,8 @@ static const struct imx_int_pll_rate_table imx8mm_intpll_tbl[] = {
 };
 
 static const struct imx_int_pll_rate_table imx8mm_audiopll_tbl[] = {
-	PLL_1443X_RATE(786432000U, 655, 5, 2, 23593),
-	PLL_1443X_RATE(722534400U, 301, 5, 1, 3670),
+	PLL_1443X_RATE(786432000U, 262, 2, 2, 9437),
+	PLL_1443X_RATE(722534400U, 361, 3, 2, 17511),
 };
 
 static const struct imx_int_pll_rate_table imx8mm_videopll_tbl[] = {
diff --git a/drivers/clk/imx/clk-intpll.c b/drivers/clk/imx/clk-intpll.c
index a783a8a67eec..4c8e0685b8ba 100644
--- a/drivers/clk/imx/clk-intpll.c
+++ b/drivers/clk/imx/clk-intpll.c
@@ -98,9 +98,12 @@ static unsigned long clk_int_pll1443x_recalc_rate(struct clk_hw *hw,
 						  unsigned long parent_rate)
 {
 	struct clk_int_pll *pll = to_clk_int_pll(hw);
+	const struct imx_int_pll_rate_table *rate_table = pll->rate_table;
 	u32 mdiv, pdiv, sdiv, pll_gnrl, pll_div_ctl0, pll_div_ctl1;
 	short int kdiv;
 	u64 fvco = parent_rate;
+	long rate = 0;
+	int i;
 
 	pll_gnrl = readl_relaxed(pll->base);
 	pll_div_ctl0 = readl_relaxed(pll->base + 4);
@@ -110,13 +113,25 @@ static unsigned long clk_int_pll1443x_recalc_rate(struct clk_hw *hw,
 	sdiv = (pll_div_ctl0 & SDIV_MASK) >> SDIV_SHIFT;
 	kdiv = pll_div_ctl1 & KDIV_MASK;
 
+	/*
+	 * Sometimes, the recalculated rate has deviation due to
+	 * the frac part. So find the accurate pll rate from the table
+	 * first, if no match rate in the table, use the rate calculated
+	 * from the equation below.
+	 */
+	for (i = 0; i < pll->rate_count; i++) {
+		if (rate_table[i].pdiv == pdiv && rate_table[i].mdiv == mdiv &&
+		    rate_table[i].sdiv == sdiv && rate_table[i].kdiv == kdiv)
+			rate = rate_table[i].rate;
+	}
+
 	/* fvco = (m * 65536 + k) * Fin / (p * 65536) */
 	fvco *= (mdiv * 65536 + kdiv);
 	pdiv *= 65536;
 
 	do_div(fvco, pdiv << sdiv);
 
-	return (unsigned long)fvco;
+	return rate ? (unsigned long) rate : (unsigned long)fvco;
 }
 
 static inline bool clk_int_pll1416x_mp_change(const struct imx_int_pll_rate_table *rate,