Export the emmc sub clock phase delay ops which will be used by the emmc sub clock driver itself.
Signed-off-by: Yixun Lan <[email protected]> --- drivers/clk/meson/Makefile | 2 +- drivers/clk/meson/clk-phase-delay.c | 96 +++++++++++++++++++++++++++++ drivers/clk/meson/clkc.h | 13 ++++ 3 files changed, 110 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/meson/clk-phase-delay.c diff --git a/drivers/clk/meson/Makefile b/drivers/clk/meson/Makefile index 72ec8c40d848..39ce5661b654 100644 --- a/drivers/clk/meson/Makefile +++ b/drivers/clk/meson/Makefile @@ -2,7 +2,7 @@ # Makefile for Meson specific clk # -obj-$(CONFIG_COMMON_CLK_AMLOGIC) += clk-pll.o clk-mpll.o clk-phase.o +obj-$(CONFIG_COMMON_CLK_AMLOGIC) += clk-pll.o clk-mpll.o clk-phase.o clk-phase-delay.o obj-$(CONFIG_COMMON_CLK_AMLOGIC_AUDIO) += clk-triphase.o sclk-div.o obj-$(CONFIG_COMMON_CLK_MESON_AO) += meson-aoclk.o obj-$(CONFIG_COMMON_CLK_MESON8B) += meson8b.o diff --git a/drivers/clk/meson/clk-phase-delay.c b/drivers/clk/meson/clk-phase-delay.c new file mode 100644 index 000000000000..6f226814cfec --- /dev/null +++ b/drivers/clk/meson/clk-phase-delay.c @@ -0,0 +1,96 @@ +// SPDX-License-Identifier: (GPL-2.0+ OR MIT) +/* + * Amlogic Meson MMC Sub Clock Controller Driver + * + * Copyright (c) 2017 Baylibre SAS. + * Author: Jerome Brunet <[email protected]> + * + * Copyright (c) 2018 Amlogic, inc. + * Author: Yixun Lan <[email protected]> + */ + +#include <linux/clk-provider.h> +#include "clkc.h" + +#define SD_EMMC_CLOCK 0 + +static int meson_clk_phase_delay_get_phase(struct clk_hw *hw) +{ + struct clk_regmap *clk = to_clk_regmap(hw); + struct meson_clk_phase_delay_data *ph = + meson_clk_get_phase_delay_data(clk); + unsigned int phase_num = 1 << hweight_long(ph->phase_mask); + unsigned long period_ps, p, d; + int degrees; + u32 val; + + regmap_read(clk->map, SD_EMMC_CLOCK, &val); + p = (val & ph->phase_mask) >> __ffs(ph->phase_mask); + degrees = p * 360 / phase_num; + + if (ph->delay_mask) { + period_ps = DIV_ROUND_UP((unsigned long)NSEC_PER_SEC * 1000, + clk_hw_get_rate(hw)); + d = (val & ph->delay_mask) >> __ffs(ph->delay_mask); + degrees += d * ph->delay_step_ps * 360 / period_ps; + degrees %= 360; + } + + return degrees; +} + +static void meson_clk_apply_phase_delay(struct clk_regmap *clk, + unsigned int phase, + unsigned int delay) +{ + struct meson_clk_phase_delay_data *ph = clk->data; + u32 val; + + regmap_read(clk->map, SD_EMMC_CLOCK, &val); + + val &= ~ph->phase_mask; + val |= phase << __ffs(ph->phase_mask); + + if (ph->delay_mask) { + val &= ~ph->delay_mask; + val |= delay << __ffs(ph->delay_mask); + } + + regmap_write(clk->map, SD_EMMC_CLOCK, val); +} + +static int meson_clk_phase_delay_set_phase(struct clk_hw *hw, int degrees) +{ + struct clk_regmap *clk = to_clk_regmap(hw); + struct meson_clk_phase_delay_data *ph = + meson_clk_get_phase_delay_data(clk); + unsigned int phase_num = 1 << hweight_long(ph->phase_mask); + unsigned long period_ps, d = 0, r; + u64 p; + + p = degrees % 360; + + if (!ph->delay_mask) { + p = DIV_ROUND_CLOSEST_ULL(p, 360 / phase_num); + } else { + period_ps = DIV_ROUND_UP((unsigned long)NSEC_PER_SEC * 1000, + clk_hw_get_rate(hw)); + + /* First compute the phase index (p), the remainder (r) is the + * part we'll try to acheive using the delays (d). + */ + r = do_div(p, 360 / phase_num); + d = DIV_ROUND_CLOSEST(r * period_ps, + 360 * ph->delay_step_ps); + d = min(d, ph->delay_mask >> __ffs(ph->delay_mask)); + } + + meson_clk_apply_phase_delay(clk, p, d); + return 0; +} + +const struct clk_ops meson_clk_phase_delay_ops = { + .get_phase = meson_clk_phase_delay_get_phase, + .set_phase = meson_clk_phase_delay_set_phase, +}; +EXPORT_SYMBOL_GPL(meson_clk_phase_delay_ops); diff --git a/drivers/clk/meson/clkc.h b/drivers/clk/meson/clkc.h index 24cec16b6038..499834dd34f2 100644 --- a/drivers/clk/meson/clkc.h +++ b/drivers/clk/meson/clkc.h @@ -113,6 +113,18 @@ struct clk_regmap _name = { \ }, \ }; +struct meson_clk_phase_delay_data { + unsigned long phase_mask; + unsigned long delay_mask; + unsigned int delay_step_ps; +}; + +static inline struct meson_clk_phase_delay_data * +meson_clk_get_phase_delay_data(struct clk_regmap *clk) +{ + return (struct meson_clk_phase_delay_data *)clk->data; +} + /* clk_ops */ extern const struct clk_ops meson_clk_pll_ro_ops; extern const struct clk_ops meson_clk_pll_ops; @@ -120,5 +132,6 @@ extern const struct clk_ops meson_clk_cpu_ops; extern const struct clk_ops meson_clk_mpll_ro_ops; extern const struct clk_ops meson_clk_mpll_ops; extern const struct clk_ops meson_clk_phase_ops; +extern const struct clk_ops meson_clk_phase_delay_ops; #endif /* __CLKC_H */ -- 2.17.1
