Add the DDRPHYC support for clk_set_rate, used in DDR interactive mode
Signed-off-by: Patrick Delaunay patrick.delaunay@st.com ---
drivers/clk/clk_stm32mp1.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 83 insertions(+)
diff --git a/drivers/clk/clk_stm32mp1.c b/drivers/clk/clk_stm32mp1.c index 24859fd..6272b00 100644 --- a/drivers/clk/clk_stm32mp1.c +++ b/drivers/clk/clk_stm32mp1.c @@ -1448,6 +1448,71 @@ static void pll_csg(struct stm32mp1_clk_priv *priv, int pll_id, u32 *csg) setbits_le32(priv->base + pll[pll_id].pllxcr, RCC_PLLNCR_SSCG_CTRL); }
+static __maybe_unused int pll_set_rate(struct udevice *dev, + int pll_id, + int div_id, + unsigned long clk_rate) +{ + struct stm32mp1_clk_priv *priv = dev_get_priv(dev); + unsigned int pllcfg[PLLCFG_NB]; + ofnode plloff; + char name[12]; + const struct stm32mp1_clk_pll *pll = priv->data->pll; + enum stm32mp1_plltype type = pll[pll_id].plltype; + int divm, divn, divy; + int ret; + ulong fck_ref; + u32 fracv; + u64 value; + + if (div_id > _DIV_NB) + return -EINVAL; + + sprintf(name, "st,pll@%d", pll_id); + plloff = dev_read_subnode(dev, name); + if (!ofnode_valid(plloff)) + return -FDT_ERR_NOTFOUND; + + ret = ofnode_read_u32_array(plloff, "cfg", + pllcfg, PLLCFG_NB); + if (ret < 0) + return -FDT_ERR_NOTFOUND; + + fck_ref = pll_get_fref_ck(priv, pll_id); + + divm = pllcfg[PLLCFG_M]; + /* select output divider = 0: for _DIV_P, 1:_DIV_Q 2:_DIV_R */ + divy = pllcfg[PLLCFG_P + div_id]; + + /* 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) + * / (DIVy + 1) * (DIVM + 1) + * value = (DIVN + 1) * 2^13 + FRACV / 2^13 + * = Fck_pll_y (DIVy + 1) * (DIVM + 1) * 2^13 / Fck_ref + */ + value = ((u64)clk_rate * (divy + 1) * (divm + 1)) << 13; + value = lldiv(value, fck_ref); + + divn = (value >> 13) - 1; + if (divn < DIVN_MIN || + divn > stm32mp1_pll[type].divn_max) { + pr_err("divn invalid = %d", divn); + return -EINVAL; + } + fracv = value - ((divn + 1) << 13); + pllcfg[PLLCFG_N] = divn; + + /* reconfigure PLL */ + pll_stop(priv, pll_id); + pll_config(priv, pll_id, pllcfg, fracv); + pll_start(priv, pll_id); + pll_output(priv, pll_id, pllcfg[PLLCFG_O]); + + return 0; +} + static int set_clksrc(struct stm32mp1_clk_priv *priv, unsigned int clksrc) { u32 address = priv->base + (clksrc >> 4); @@ -1820,6 +1885,11 @@ static ulong stm32mp1_clk_set_rate(struct clk *clk, unsigned long clk_rate) int p;
switch (clk->id) { +#if defined(STM32MP1_CLOCK_TREE_INIT) && \ + defined(CONFIG_STM32MP1_DDR_INTERACTIVE) + case DDRPHYC: + break; +#endif case LTDC_PX: case DSI_PX: break; @@ -1833,6 +1903,19 @@ static ulong stm32mp1_clk_set_rate(struct clk *clk, unsigned long clk_rate) return -EINVAL;
switch (p) { +#if defined(STM32MP1_CLOCK_TREE_INIT) && \ + defined(CONFIG_STM32MP1_DDR_INTERACTIVE) + case _PLL2_R: /* DDRPHYC */ + { + /* only for change DDR clock in interactive mode */ + ulong result; + + set_clksrc(priv, CLK_AXI_HSI); + result = pll_set_rate(clk->dev, _PLL2, _DIV_R, clk_rate); + set_clksrc(priv, CLK_AXI_PLL2P); + return result; + } +#endif case _PLL4_Q: /* for LTDC_PX and DSI_PX case */ return pll_set_output_rate(clk->dev, _PLL4, _DIV_Q, clk_rate);