From: Lucas Stach <l.st...@pengutronix.de> The SCCG is a new PLL type introduced on i.MX8.
The description of this SCCG clock can be found here: https://www.nxp.com/docs/en/reference-manual/IMX8MDQLQRM.pdf#page=834 Signed-off-by: Lucas Stach <l.st...@pengutronix.de> Signed-off-by: Abel Vesa <abel.v...@nxp.com> Reviewed-by: Sascha Hauer <s.ha...@pengutronix.de> --- drivers/clk/imx/Makefile | 3 +- drivers/clk/imx/clk-sccg-pll.c | 256 +++++++++++++++++++++++++++++++++++++++++ drivers/clk/imx/clk.h | 9 ++ 3 files changed, 267 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/imx/clk-sccg-pll.c diff --git a/drivers/clk/imx/Makefile b/drivers/clk/imx/Makefile index 4893c1f..b87513c 100644 --- a/drivers/clk/imx/Makefile +++ b/drivers/clk/imx/Makefile @@ -12,7 +12,8 @@ obj-y += \ clk-pllv1.o \ clk-pllv2.o \ clk-pllv3.o \ - clk-pfd.o + clk-pfd.o \ + clk-sccg-pll.o obj-$(CONFIG_SOC_IMX1) += clk-imx1.o obj-$(CONFIG_SOC_IMX21) += clk-imx21.o diff --git a/drivers/clk/imx/clk-sccg-pll.c b/drivers/clk/imx/clk-sccg-pll.c new file mode 100644 index 0000000..4666b96 --- /dev/null +++ b/drivers/clk/imx/clk-sccg-pll.c @@ -0,0 +1,256 @@ +// SPDX-License-Identifier: (GPL-2.0 OR MIT) +/* + * Copyright 2018 NXP. + * + * This driver supports the SCCG plls found in the imx8m SOCs + * + * Documentation for this SCCG pll can be found at: + * https://www.nxp.com/docs/en/reference-manual/IMX8MDQLQRM.pdf#page=834 + */ + +#include <linux/clk-provider.h> +#include <linux/err.h> +#include <linux/iopoll.h> +#include <linux/slab.h> +#include <linux/bitfield.h> + +#include "clk.h" + +/* PLL CFGs */ +#define PLL_CFG0 0x0 +#define PLL_CFG1 0x4 +#define PLL_CFG2 0x8 + +#define PLL_DIVF1_MASK GENMASK(18, 13) +#define PLL_DIVF2_MASK GENMASK(12, 7) +#define PLL_DIVR1_MASK GENMASK(27, 25) +#define PLL_DIVR2_MASK GENMASK(24, 19) +#define PLL_REF_MASK GENMASK(2, 0) + +#define PLL_LOCK_MASK BIT(31) +#define PLL_PD_MASK BIT(7) + +#define OSC_25M 25000000 +#define OSC_27M 27000000 + +#define PLL_SCCG_LOCK_TIMEOUT 70 + +struct clk_sccg_pll { + struct clk_hw hw; + void __iomem *base; +}; + +#define to_clk_sccg_pll(_hw) container_of(_hw, struct clk_sccg_pll, hw) + +static int clk_pll_wait_lock(struct clk_sccg_pll *pll) +{ + u32 val; + + return readl_poll_timeout(pll->base, val, val & PLL_LOCK_MASK, 0, + PLL_SCCG_LOCK_TIMEOUT); +} + +static int clk_pll1_is_prepared(struct clk_hw *hw) +{ + struct clk_sccg_pll *pll = to_clk_sccg_pll(hw); + u32 val; + + val = readl_relaxed(pll->base + PLL_CFG0); + return (val & PLL_PD_MASK) ? 0 : 1; +} + +static unsigned long clk_pll1_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_sccg_pll *pll = to_clk_sccg_pll(hw); + u32 val, divf; + + val = readl_relaxed(pll->base + PLL_CFG2); + divf = FIELD_GET(PLL_DIVF1_MASK, val); + + return parent_rate * 2 * (divf + 1); +} + +static long clk_pll1_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + unsigned long parent_rate = *prate; + u32 div; + + if (!parent_rate) + return 0; + + div = rate / (parent_rate * 2); + + return parent_rate * div * 2; +} + +static int clk_pll1_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_sccg_pll *pll = to_clk_sccg_pll(hw); + u32 val; + u32 divf; + + if (!parent_rate) + return -EINVAL; + + divf = rate / (parent_rate * 2); + + val = readl_relaxed(pll->base + PLL_CFG2); + val &= ~PLL_DIVF1_MASK; + val |= FIELD_PREP(PLL_DIVF1_MASK, divf - 1); + writel_relaxed(val, pll->base + PLL_CFG2); + + return clk_pll_wait_lock(pll); +} + +static int clk_pll1_prepare(struct clk_hw *hw) +{ + struct clk_sccg_pll *pll = to_clk_sccg_pll(hw); + u32 val; + + val = readl_relaxed(pll->base + PLL_CFG0); + val &= ~PLL_PD_MASK; + writel_relaxed(val, pll->base + PLL_CFG0); + + return clk_pll_wait_lock(pll); +} + +static void clk_pll1_unprepare(struct clk_hw *hw) +{ + struct clk_sccg_pll *pll = to_clk_sccg_pll(hw); + u32 val; + + val = readl_relaxed(pll->base + PLL_CFG0); + val |= PLL_PD_MASK; + writel_relaxed(val, pll->base + PLL_CFG0); + +} + +static unsigned long clk_pll2_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_sccg_pll *pll = to_clk_sccg_pll(hw); + u32 val, ref, divr1, divf1, divr2, divf2; + u64 temp64; + + val = readl_relaxed(pll->base + PLL_CFG0); + switch (FIELD_GET(PLL_REF_MASK, val)) { + case 0: + ref = OSC_25M; + break; + case 1: + ref = OSC_27M; + break; + default: + ref = OSC_25M; + break; + } + + val = readl_relaxed(pll->base + PLL_CFG2); + divr1 = FIELD_GET(PLL_DIVR1_MASK, val); + divr2 = FIELD_GET(PLL_DIVR2_MASK, val); + divf1 = FIELD_GET(PLL_DIVF1_MASK, val); + divf2 = FIELD_GET(PLL_DIVF2_MASK, val); + + temp64 = ref * 2; + temp64 *= (divf1 + 1) * (divf2 + 1); + + do_div(temp64, (divr1 + 1) * (divr2 + 1)); + + return temp64; +} + +static long clk_pll2_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + u32 div; + unsigned long parent_rate = *prate; + + if (!parent_rate) + return 0; + + div = rate / parent_rate; + + return parent_rate * div; +} + +static int clk_pll2_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + u32 val; + u32 divf; + struct clk_sccg_pll *pll = to_clk_sccg_pll(hw); + + if (!parent_rate) + return -EINVAL; + + divf = rate / parent_rate; + + val = readl_relaxed(pll->base + PLL_CFG2); + val &= ~PLL_DIVF2_MASK; + val |= FIELD_PREP(PLL_DIVF2_MASK, divf - 1); + writel_relaxed(val, pll->base + PLL_CFG2); + + return clk_pll_wait_lock(pll); +} + +static const struct clk_ops clk_sccg_pll1_ops = { + .is_prepared = clk_pll1_is_prepared, + .recalc_rate = clk_pll1_recalc_rate, + .round_rate = clk_pll1_round_rate, + .set_rate = clk_pll1_set_rate, +}; + +static const struct clk_ops clk_sccg_pll2_ops = { + .prepare = clk_pll1_prepare, + .unprepare = clk_pll1_unprepare, + .recalc_rate = clk_pll2_recalc_rate, + .round_rate = clk_pll2_round_rate, + .set_rate = clk_pll2_set_rate, +}; + +struct clk *imx_clk_sccg_pll(const char *name, + const char *parent_name, + void __iomem *base, + enum imx_sccg_pll_type pll_type) +{ + struct clk_sccg_pll *pll; + struct clk_init_data init; + struct clk_hw *hw; + int ret; + + switch (pll_type) { + case SCCG_PLL1: + init.ops = &clk_sccg_pll1_ops; + break; + case SCCG_PLL2: + init.ops = &clk_sccg_pll2_ops; + break; + default: + return ERR_PTR(-EINVAL); + } + + pll = kzalloc(sizeof(*pll), GFP_KERNEL); + if (!pll) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.flags = 0; + init.parent_names = &parent_name; + init.num_parents = 1; + + pll->base = base; + pll->hw.init = &init; + + hw = &pll->hw; + + ret = clk_hw_register(NULL, hw); + if (ret) { + kfree(pll); + return ERR_CAST(hw); + } + + return hw->clk; +} diff --git a/drivers/clk/imx/clk.h b/drivers/clk/imx/clk.h index 44a1f14..864cd8a 100644 --- a/drivers/clk/imx/clk.h +++ b/drivers/clk/imx/clk.h @@ -21,6 +21,11 @@ enum imx_pllv1_type { IMX_PLLV1_IMX35, }; +enum imx_sccg_pll_type { + SCCG_PLL1, + SCCG_PLL2, +}; + struct clk *imx_clk_pllv1(enum imx_pllv1_type type, const char *name, const char *parent, void __iomem *base); @@ -30,6 +35,10 @@ struct clk *imx_clk_pllv2(const char *name, const char *parent, struct clk *imx_clk_frac_pll(const char *name, const char *parent_name, void __iomem *base); +struct clk *imx_clk_sccg_pll(const char *name, const char *parent_name, + void __iomem *base, + enum imx_sccg_pll_type pll_type); + enum imx_pllv3_type { IMX_PLLV3_GENERIC, IMX_PLLV3_SYS, -- 2.7.4
