stm32mp1: clk: add common function pll_get_fvco
the function compute the VCO PLL freq, used in
- stm32mp1_read_pll_freq()
- pll_set_rate()
Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
# Conflicts:
# drivers/clk/clk_stm32mp1.c
diff --git a/drivers/clk/clk_stm32mp1.c b/drivers/clk/clk_stm32mp1.c
index 10e3836..317526a 100644
--- a/drivers/clk/clk_stm32mp1.c
+++ b/drivers/clk/clk_stm32mp1.c
@@ -808,56 +808,87 @@
return -EINVAL;
}
-static ulong stm32mp1_read_pll_freq(struct stm32mp1_clk_priv *priv,
- int pll_id, int div_id)
+static ulong pll_get_fref_ck(struct stm32mp1_clk_priv *priv,
+ int pll_id)
{
const struct stm32mp1_clk_pll *pll = priv->data->pll;
- int divm, divn, divy, src;
- ulong refclk, dfout;
- u32 selr, cfgr1, cfgr2, fracr;
+ u32 selr;
+ int src;
+ ulong refclk;
- debug("%s(%d, %d)\n", __func__, pll_id, div_id);
- if (div_id > _DIV_NB)
- return 0;
-
+ /* Get current refclk */
selr = readl(priv->base + pll[pll_id].rckxselr);
- cfgr1 = readl(priv->base + pll[pll_id].pllxcfgr1);
- cfgr2 = readl(priv->base + pll[pll_id].pllxcfgr2);
- fracr = readl(priv->base + pll[pll_id].pllxfracr);
+ src = selr & RCC_SELR_SRC_MASK;
- debug("PLL%d : selr=%x cfgr1=%x cfgr2=%x fracr=%x\n",
- pll_id, selr, cfgr1, cfgr2, fracr);
+ refclk = stm32mp1_clk_get_fixed(priv, pll[pll_id].refclk[src]);
+ debug("PLL%d : selr=%x refclk = %d kHz\n",
+ pll_id, selr, (u32)(refclk / 1000));
+
+ return refclk;
+}
+
+/*
+ * pll_get_fvco() : return the VCO or (VCO / 2) frequency for the requested PLL
+ * - PLL1 & PLL2 => return VCO / 2 with Fpll_y_ck = FVCO / 2 * (DIVy + 1)
+ * - PLL3 & PLL4 => return VCO with Fpll_y_ck = FVCO / (DIVy + 1)
+ * => in all the case Fpll_y_ck = pll_get_fvco() / (DIVy + 1)
+ */
+static ulong pll_get_fvco(struct stm32mp1_clk_priv *priv,
+ int pll_id)
+{
+ const struct stm32mp1_clk_pll *pll = priv->data->pll;
+ int divm, divn;
+ ulong refclk, fvco;
+ u32 cfgr1, fracr;
+
+ cfgr1 = readl(priv->base + pll[pll_id].pllxcfgr1);
+ fracr = readl(priv->base + pll[pll_id].pllxfracr);
divm = (cfgr1 & (RCC_PLLNCFGR1_DIVM_MASK)) >> RCC_PLLNCFGR1_DIVM_SHIFT;
divn = cfgr1 & RCC_PLLNCFGR1_DIVN_MASK;
- divy = (cfgr2 >> RCC_PLLNCFGR2_SHIFT(div_id)) & RCC_PLLNCFGR2_DIVX_MASK;
- debug(" DIVN=%d DIVM=%d DIVY=%d\n", divn, divm, divy);
+ debug("PLL%d : cfgr1=%x fracr=%x DIVN=%d DIVM=%d\n",
+ pll_id, cfgr1, fracr, divn, divm);
- src = selr & RCC_SELR_SRC_MASK;
- refclk = stm32mp1_clk_get_fixed(priv, pll[pll_id].refclk[src]);
+ refclk = pll_get_fref_ck(priv, pll_id);
- debug(" refclk = %d kHz\n", (u32)(refclk / 1000));
-
- /*
- * For: PLL1 & PLL2 => VCO is * 2 but ck_pll_y is also / 2
- * So same final result than PLL2 et 4
- * with FRACV :
- * Fck_pll_y = Fck_ref * ((DIVN + 1) + FRACV / 2^13)
- * / (DIVM + 1) * (DIVy + 1)
+ /* with FRACV :
+ * Fvco = Fck_ref * ((DIVN + 1) + FRACV / 2^13) / (DIVM + 1)
* without FRACV
- * Fck_pll_y = Fck_ref * ((DIVN + 1) / (DIVM + 1) *(DIVy + 1)
+ * Fvco = Fck_ref * ((DIVN + 1) / (DIVM + 1)
*/
if (fracr & RCC_PLLNFRACR_FRACLE) {
u32 fracv = (fracr & RCC_PLLNFRACR_FRACV_MASK)
>> RCC_PLLNFRACR_FRACV_SHIFT;
- dfout = (ulong)lldiv((unsigned long long)refclk *
+ fvco = (ulong)lldiv((unsigned long long)refclk *
(((divn + 1) << 13) + fracv),
- ((unsigned long long)(divm + 1) *
- (divy + 1)) << 13);
+ ((unsigned long long)(divm + 1)) << 13);
} else {
- dfout = (ulong)(refclk * (divn + 1) / (divm + 1) * (divy + 1));
+ fvco = (ulong)(refclk * (divn + 1) / (divm + 1));
}
+ debug("PLL%d : %s = %ld\n", pll_id, __func__, fvco);
+
+ return fvco;
+}
+
+static ulong stm32mp1_read_pll_freq(struct stm32mp1_clk_priv *priv,
+ int pll_id, int div_id)
+{
+ const struct stm32mp1_clk_pll *pll = priv->data->pll;
+ int divy;
+ ulong dfout;
+ u32 cfgr2;
+
+ debug("%s(%d, %d)\n", __func__, pll_id, div_id);
+ if (div_id >= _DIV_NB)
+ return 0;
+
+ cfgr2 = readl(priv->base + pll[pll_id].pllxcfgr2);
+ divy = (cfgr2 >> RCC_PLLNCFGR2_SHIFT(div_id)) & RCC_PLLNCFGR2_DIVX_MASK;
+
+ debug("PLL%d : cfgr2=%x DIVY=%d\n", pll_id, cfgr2, divy);
+
+ dfout = pll_get_fvco(priv, pll_id) / (divy + 1);
debug(" => dfout = %d kHz\n", (u32)(dfout / 1000));
return dfout;