[PATCH v4 2/7] clk: starfive: Add StarFive JH7110 PLL clock driver

Emil Renner Berthing emil.renner.berthing at canonical.com
Thu Jun 1 04:02:48 PDT 2023


Hi Xingyu,

Thanks for working on this.

On Fri, 12 May 2023 at 04:24, Xingyu Wu <xingyu.wu at starfivetech.com> wrote:
>
> Add driver for the StarFive JH7110 PLL clock controller
> and they work by reading and setting syscon registers.
>
> Signed-off-by: Xingyu Wu <xingyu.wu at starfivetech.com>
> ---
>  MAINTAINERS                                   |   6 +
>  drivers/clk/starfive/Kconfig                  |   8 +
>  drivers/clk/starfive/Makefile                 |   1 +
>  .../clk/starfive/clk-starfive-jh7110-pll.c    | 309 ++++++++++++++++
>  .../clk/starfive/clk-starfive-jh7110-pll.h    | 331 ++++++++++++++++++
>  5 files changed, 655 insertions(+)
>  create mode 100644 drivers/clk/starfive/clk-starfive-jh7110-pll.c
>  create mode 100644 drivers/clk/starfive/clk-starfive-jh7110-pll.h
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 7e0b87d5aa2e..0fb4a703f66f 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -20087,6 +20087,12 @@ S:     Supported
>  F:     Documentation/devicetree/bindings/mmc/starfive*
>  F:     drivers/mmc/host/dw_mmc-starfive.c
>
> +STARFIVE JH7110 PLL CLOCK DRIVER
> +M:     Xingyu Wu <xingyu.wu at starfivetech.com>
> +S:     Supported
> +F:     Documentation/devicetree/bindings/clock/starfive,jh7110-pll.yaml
> +F:     drivers/clk/starfive/clk-starfive-jh7110-pll.*
> +
>  STARFIVE JH71X0 CLOCK DRIVERS
>  M:     Emil Renner Berthing <kernel at esmil.dk>
>  M:     Hal Feng <hal.feng at starfivetech.com>
> diff --git a/drivers/clk/starfive/Kconfig b/drivers/clk/starfive/Kconfig
> index 5d2333106f13..5195f7be5213 100644
> --- a/drivers/clk/starfive/Kconfig
> +++ b/drivers/clk/starfive/Kconfig
> @@ -21,6 +21,14 @@ config CLK_STARFIVE_JH7100_AUDIO
>           Say Y or M here to support the audio clocks on the StarFive JH7100
>           SoC.
>
> +config CLK_STARFIVE_JH7110_PLL
> +       bool "StarFive JH7110 PLL clock support"
> +       depends on ARCH_STARFIVE || COMPILE_TEST
> +       default ARCH_STARFIVE
> +       help
> +         Say yes here to support the PLL clock controller on the
> +         StarFive JH7110 SoC.
> +
>  config CLK_STARFIVE_JH7110_SYS
>         bool "StarFive JH7110 system clock support"
>         depends on ARCH_STARFIVE || COMPILE_TEST
> diff --git a/drivers/clk/starfive/Makefile b/drivers/clk/starfive/Makefile
> index f3df7d957b1e..b48e539e52b0 100644
> --- a/drivers/clk/starfive/Makefile
> +++ b/drivers/clk/starfive/Makefile
> @@ -4,5 +4,6 @@ obj-$(CONFIG_CLK_STARFIVE_JH71X0)       += clk-starfive-jh71x0.o
>  obj-$(CONFIG_CLK_STARFIVE_JH7100)      += clk-starfive-jh7100.o
>  obj-$(CONFIG_CLK_STARFIVE_JH7100_AUDIO)        += clk-starfive-jh7100-audio.o
>
> +obj-$(CONFIG_CLK_STARFIVE_JH7110_PLL)  += clk-starfive-jh7110-pll.o
>  obj-$(CONFIG_CLK_STARFIVE_JH7110_SYS)  += clk-starfive-jh7110-sys.o
>  obj-$(CONFIG_CLK_STARFIVE_JH7110_AON)  += clk-starfive-jh7110-aon.o
> diff --git a/drivers/clk/starfive/clk-starfive-jh7110-pll.c b/drivers/clk/starfive/clk-starfive-jh7110-pll.c
> new file mode 100644
> index 000000000000..f86deddd4bef
> --- /dev/null
> +++ b/drivers/clk/starfive/clk-starfive-jh7110-pll.c
> @@ -0,0 +1,309 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * StarFive JH7110 PLL Clock Generator Driver
> + *
> + * Copyright (C) 2023 StarFive Technology Co., Ltd.
> + *
> + * This driver is about to register JH7110 PLL clock generator and support ops.
> + * The JH7110 have three PLL clock, PLL0, PLL1 and PLL2.
> + * Each PLL clocks work in integer mode or fraction mode by some dividers,
> + * and the configuration registers and dividers are set in several syscon registers.
> + * The formula for calculating frequency is:
> + * Fvco = Fref * (NI + NF) / M / Q1
> + * Fref: OSC source clock rate
> + * NI: integer frequency dividing ratio of feedback divider, set by fbdiv[11:0].
> + * NF: fractional frequency dividing ratio, set by frac[23:0]. NF = frac[23:0] / 2^24 = 0 ~ 0.999.
> + * M: frequency dividing ratio of pre-divider, set by prediv[5:0].
> + * Q1: frequency dividing ratio of post divider, set by postdiv1[1:0], Q1= 1,2,4,8.
> + */
> +
> +#include <linux/clk-provider.h>
> +#include <linux/debugfs.h>
> +#include <linux/device.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +
> +#include <dt-bindings/clock/starfive,jh7110-crg.h>
> +
> +#include "clk-starfive-jh7110-pll.h"
> +
> +struct jh7110_pll_conf_variant {
> +       unsigned int pll_nums;
> +       struct jh7110_pll_syscon_conf conf[];
> +};
> +
> +static const struct jh7110_pll_conf_variant jh7110_pll_variant = {
> +       .pll_nums = JH7110_PLLCLK_END,
> +       .conf = {
> +               JH7110_PLL(JH7110_CLK_PLL0_OUT, "pll0_out",
> +                          JH7110_PLL0_FREQ_MAX, jh7110_pll0_syscon_val_preset),
> +               JH7110_PLL(JH7110_CLK_PLL1_OUT, "pll1_out",
> +                          JH7110_PLL1_FREQ_MAX, jh7110_pll1_syscon_val_preset),
> +               JH7110_PLL(JH7110_CLK_PLL2_OUT, "pll2_out",
> +                          JH7110_PLL2_FREQ_MAX, jh7110_pll2_syscon_val_preset),
> +       },
> +};
> +
> +static struct jh7110_clk_pll_data *jh7110_pll_data_from(struct clk_hw *hw)
> +{
> +       return container_of(hw, struct jh7110_clk_pll_data, hw);
> +}
> +
> +static struct jh7110_clk_pll_priv *jh7110_pll_priv_from(struct jh7110_clk_pll_data *data)
> +{
> +       return container_of(data, struct jh7110_clk_pll_priv, data[data->idx]);
> +}
> +
> +/* Read register value from syscon and calculate PLL(x) frequency */
> +static unsigned long jh7110_pll_get_freq(struct jh7110_clk_pll_data *data,
> +                                        unsigned long parent_rate)
> +{
> +       struct jh7110_clk_pll_priv *priv = jh7110_pll_priv_from(data);
> +       struct jh7110_pll_syscon_offset *offset = &data->conf.offsets;
> +       struct jh7110_pll_syscon_mask *mask = &data->conf.masks;
> +       struct jh7110_pll_syscon_shift *shift = &data->conf.shifts;
> +       unsigned long frac_cal;
> +       u32 dacpd;
> +       u32 dsmpd;
> +       u32 fbdiv;
> +       u32 prediv;
> +       u32 postdiv1;
> +       u32 frac;
> +       u32 reg_val;
> +
> +       regmap_read(priv->syscon_regmap, offset->dacpd, &reg_val);
> +       dacpd = (reg_val & mask->dacpd) >> shift->dacpd;
> +
> +       regmap_read(priv->syscon_regmap, offset->dsmpd, &reg_val);
> +       dsmpd = (reg_val & mask->dsmpd) >> shift->dsmpd;
> +
> +       regmap_read(priv->syscon_regmap, offset->fbdiv, &reg_val);
> +       fbdiv = (reg_val & mask->fbdiv) >> shift->fbdiv;
> +
> +       regmap_read(priv->syscon_regmap, offset->prediv, &reg_val);
> +       prediv = (reg_val & mask->prediv) >> shift->prediv;
> +
> +       regmap_read(priv->syscon_regmap, offset->postdiv1, &reg_val);
> +       /* postdiv1 = 2 ^ reg_val */
> +       postdiv1 = 1 << ((reg_val & mask->postdiv1) >> shift->postdiv1);
> +
> +       regmap_read(priv->syscon_regmap, offset->frac, &reg_val);
> +       frac = (reg_val & mask->frac) >> shift->frac;
> +
> +       /*
> +        * Integer Mode (Both 1) or Fraction Mode (Both 0).
> +        * And the decimal places are counted by expanding them by
> +        * a factor of STARFIVE_PLL_FRAC_PATR_SIZE.
> +        */
> +       if (dacpd == 1 && dsmpd == 1)
> +               frac_cal = 0;
> +       else if (dacpd == 0 && dsmpd == 0)
> +               frac_cal = (unsigned long)frac * STARFIVE_PLL_FRAC_PATR_SIZE / (1 << 24);
> +       else
> +               return 0;
> +
> +       /* Fvco = Fref * (NI + NF) / M / Q1 */
> +       return (parent_rate / STARFIVE_PLL_FRAC_PATR_SIZE *
> +               (fbdiv * STARFIVE_PLL_FRAC_PATR_SIZE + frac_cal) / prediv / postdiv1);

You have

  rate = parent * (fbdiv + frac/2^24) / prediv / 2^postdiv1regval

Where postdiv1regval is the raw postdiv1 register value. This can also
be written

  rate = (parent * fbdiv + parent * frac / 2^24) / (prediv * 2^postdiv1regval)

so how about

if (dacpd == 1 && dsmpd == 1)
  rate = 0;
else if (dacpd == 0 && dsmpd == 0)
  rate = parent * frac / (1UL << 24);
else
  return 0;

rate += parent * fbdiv;
rate /= prediv << postdiv1regval;
return rate;

> +}
> +
> +static unsigned long jh7110_pll_rate_sub_fabs(unsigned long rate1, unsigned long rate2)
> +{
> +       return rate1 > rate2 ? (rate1 - rate2) : (rate2 - rate1);
> +}
> +
> +/* Select the appropriate frequency from the already configured registers value */
> +static void jh7110_pll_select_near_freq_id(struct jh7110_clk_pll_data *data,
> +                                          unsigned long rate)
> +{
> +       const struct jh7110_pll_syscon_val *val;
> +       unsigned int id;
> +       unsigned long rate_diff;
> +
> +       /* compare the frequency one by one from small to large in order */
> +       for (id = 0; id < data->conf.preset_val_nums; id++) {
> +               val = &data->conf.preset_val[id];
> +
> +               if (rate == val->freq)
> +                       goto match_end;
> +
> +               /* select near frequency */

Is there any reason we can't just pick the highest rate <= the
requested rate, just like we do for the regular clock dividers?

> +               if (rate < val->freq) {
> +                       /* The last frequency is closer to the target rate than this time. */
> +                       if (id > 0)
> +                               if (rate_diff < jh7110_pll_rate_sub_fabs(rate, val->freq))
> +                                       id--;
> +
> +                       goto match_end;
> +               } else {
> +                       rate_diff = jh7110_pll_rate_sub_fabs(rate, val->freq);
> +               }
> +       }
> +
> +match_end:
> +       data->freq_select_idx = id;
> +}
> +
> +static int jh7110_pll_set_freq_syscon(struct jh7110_clk_pll_data *data)
> +{
> +       struct jh7110_clk_pll_priv *priv = jh7110_pll_priv_from(data);
> +       struct jh7110_pll_syscon_offset *offset = &data->conf.offsets;
> +       struct jh7110_pll_syscon_mask *mask = &data->conf.masks;
> +       struct jh7110_pll_syscon_shift *shift = &data->conf.shifts;
> +       const struct jh7110_pll_syscon_val *val = &data->conf.preset_val[data->freq_select_idx];
> +
> +       /* frac: Integer Mode (Both 1) or Fraction Mode (Both 0) */
> +       if (val->dacpd == 0 && val->dsmpd == 0)
> +               regmap_update_bits(priv->syscon_regmap, offset->frac, mask->frac,
> +                                  (val->frac << shift->frac));
> +       else if (val->dacpd != val->dsmpd)
> +               return -EINVAL;
> +
> +       /* fbdiv value should be 8 to 4095 */
> +       if (val->fbdiv < 8)
> +               return -EINVAL;
> +
> +       regmap_update_bits(priv->syscon_regmap, offset->dacpd, mask->dacpd,
> +                          (val->dacpd << shift->dacpd));
> +       regmap_update_bits(priv->syscon_regmap, offset->dsmpd, mask->dsmpd,
> +                          (val->dsmpd << shift->dsmpd));
> +       regmap_update_bits(priv->syscon_regmap, offset->prediv, mask->prediv,
> +                          (val->prediv << shift->prediv));
> +       regmap_update_bits(priv->syscon_regmap, offset->fbdiv, mask->fbdiv,
> +                          (val->fbdiv << shift->fbdiv));
> +       regmap_update_bits(priv->syscon_regmap, offset->postdiv1, mask->postdiv1,
> +                          ((val->postdiv1 >> 1) << shift->postdiv1));

It seems like you're storing the divider and not the register value in
the presets. Since the divider is 2^regval it means you need to write
log2 (divider) into the register, but here you store divider >> 1 aka
divider / 2.

I'd strongly suggest you just store the register value, and just use
2^regval when you need the divider. This way you won't need to ever
calculate log2 of anything.

> +
> +       return 0;
> +}
> +
> +static unsigned long jh7110_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
> +{
> +       struct jh7110_clk_pll_data *data = jh7110_pll_data_from(hw);
> +
> +       return jh7110_pll_get_freq(data, parent_rate);
> +}
> +
> +static int jh7110_pll_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
> +{
> +       struct jh7110_clk_pll_data *data = jh7110_pll_data_from(hw);

What happens if the parent rate != 24MHz? Then all your presets will
be wrong. We probably want to guard against that.

> +       jh7110_pll_select_near_freq_id(data, req->rate);
> +       req->rate = data->conf.preset_val[data->freq_select_idx].freq;
> +
> +       return 0;
> +}
> +
> +static int jh7110_pll_set_rate(struct clk_hw *hw, unsigned long rate,
> +                              unsigned long parent_rate)
> +{
> +       struct jh7110_clk_pll_data *data = jh7110_pll_data_from(hw);
> +
> +       return jh7110_pll_set_freq_syscon(data);
> +}
> +
> +#ifdef CONFIG_DEBUG_FS
> +static void jh7110_pll_debug_init(struct clk_hw *hw, struct dentry *dentry)
> +{
> +       static const struct debugfs_reg32 jh7110_clk_pll_reg = {
> +               .name = "CTRL",
> +               .offset = 0,
> +       };
> +       struct jh7110_clk_pll_data *data = jh7110_pll_data_from(hw);
> +       struct jh7110_clk_pll_priv *priv = jh7110_pll_priv_from(data);
> +       struct debugfs_regset32 *regset;
> +
> +       regset = devm_kzalloc(priv->dev, sizeof(*regset), GFP_KERNEL);
> +       if (!regset)
> +               return;
> +
> +       regset->regs = &jh7110_clk_pll_reg;
> +       regset->nregs = 1;

You never set regset->base, so this function creates a registers file
that just shows the contents of address 0. I don't think you tested
this.

> +
> +       debugfs_create_regset32("registers", 0400, dentry, regset);
> +}
> +#else
> +#define jh7110_pll_debug_init NULL
> +#endif
> +
> +static const struct clk_ops jh7110_pll_ops = {
> +       .recalc_rate = jh7110_pll_recalc_rate,
> +       .determine_rate = jh7110_pll_determine_rate,
> +       .set_rate = jh7110_pll_set_rate,
> +       .debug_init = jh7110_pll_debug_init,
> +};
> +
> +static struct clk_hw *jh7110_pll_get(struct of_phandle_args *clkspec, void *data)
> +{
> +       struct jh7110_clk_pll_priv *priv = data;
> +       unsigned int idx = clkspec->args[0];
> +
> +       if (idx < priv->pll_nums)
> +               return &priv->data[idx].hw;
> +
> +       return ERR_PTR(-EINVAL);
> +}
> +
> +static int jh7110_pll_probe(struct platform_device *pdev)
> +{
> +       const struct jh7110_pll_conf_variant *variant;
> +       struct jh7110_clk_pll_priv *priv;
> +       struct jh7110_clk_pll_data *data;
> +       int ret;
> +       unsigned int idx;
> +
> +       variant = of_device_get_match_data(&pdev->dev);
> +       if (!variant)
> +               return -ENOMEM;
> +
> +       priv = devm_kzalloc(&pdev->dev, struct_size(priv, data, variant->pll_nums),
> +                           GFP_KERNEL);
> +       if (!priv)
> +               return -ENOMEM;
> +
> +       priv->dev = &pdev->dev;
> +       priv->syscon_regmap = syscon_node_to_regmap(priv->dev->of_node->parent);
> +       if (IS_ERR(priv->syscon_regmap))
> +               return PTR_ERR(priv->syscon_regmap);
> +
> +       priv->pll_nums = variant->pll_nums;
> +       for (idx = 0; idx < priv->pll_nums; idx++) {
> +               struct clk_parent_data parents = {
> +                       .index = 0,
> +               };
> +               struct clk_init_data init = {
> +                       .name = variant->conf[idx].name,
> +                       .ops = &jh7110_pll_ops,
> +                       .parent_data = &parents,
> +                       .num_parents = 1,
> +                       .flags = 0,
> +               };
> +
> +               data = &priv->data[idx];
> +               data->conf = variant->conf[idx];

Why do you need to copy all this static data? Can't you just reference
the static const version you already have?

> +               data->hw.init = &init;
> +               data->idx = idx;
> +
> +               ret = devm_clk_hw_register(&pdev->dev, &data->hw);
> +               if (ret)
> +                       return ret;
> +       }
> +
> +       return devm_of_clk_add_hw_provider(&pdev->dev, jh7110_pll_get, priv);
> +}
> +
> +static const struct of_device_id jh7110_pll_match[] = {
> +       { .compatible = "starfive,jh7110-pll", .data = &jh7110_pll_variant },
> +       { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, jh7110_pll_match);
> +
> +static struct platform_driver jh7110_pll_driver = {
> +       .driver = {
> +               .name = "clk-starfive-jh7110-pll",
> +               .of_match_table = jh7110_pll_match,
> +       },
> +};
> +builtin_platform_driver_probe(jh7110_pll_driver, jh7110_pll_probe);
> diff --git a/drivers/clk/starfive/clk-starfive-jh7110-pll.h b/drivers/clk/starfive/clk-starfive-jh7110-pll.h
> new file mode 100644
> index 000000000000..526f21670fe3
> --- /dev/null
> +++ b/drivers/clk/starfive/clk-starfive-jh7110-pll.h

This header is never used outside of clk-starfive-jh7110-pll.c. Please
just merge it into that file.

> @@ -0,0 +1,331 @@
> +/* SPDX-License-Identifier: GPL-2.0 OR MIT */
> +/*
> + * StarFive JH7110 PLL Clock Generator Driver
> + *
> + * Copyright (C) 2023 StarFive Technology Co., Ltd.
> + */
> +
> +#ifndef _CLK_STARFIVE_JH7110_PLL_H_
> +#define _CLK_STARFIVE_JH7110_PLL_H_
> +
> +#include <linux/bits.h>
> +
> +/* The decimal places are counted by expanding them by a factor of STARFIVE_PLL_FRAC_PATR_SIZE */
> +#define STARFIVE_PLL_FRAC_PATR_SIZE            1000
> +
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_DACPD_OFFSET      0x18
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_DACPD_SHIFT       24
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_DACPD_MASK                BIT(24)
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_DSMPD_OFFSET      0x18
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_DSMPD_SHIFT       25
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_DSMPD_MASK                BIT(25)
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_FBDIV_OFFSET      0x1c
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_FBDIV_SHIFT       0
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_FBDIV_MASK                GENMASK(11, 0)
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_FRAC_OFFSET       0x20
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_FRAC_SHIFT                0
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_FRAC_MASK         GENMASK(23, 0)
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_POSTDIV1_OFFSET   0x20
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_POSTDIV1_SHIFT    28
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_POSTDIV1_MASK     GENMASK(29, 28)
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_PREDIV_OFFSET     0x24
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_PREDIV_SHIFT      0
> +#define STARFIVE_JH7110_CLK_PLL0_OUT_PREDIV_MASK       GENMASK(5, 0)
> +
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_DACPD_OFFSET      0x24
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_DACPD_SHIFT       15
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_DACPD_MASK                BIT(15)
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_DSMPD_OFFSET      0x24
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_DSMPD_SHIFT       16
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_DSMPD_MASK                BIT(16)
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_FBDIV_OFFSET      0x24
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_FBDIV_SHIFT       17
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_FBDIV_MASK                GENMASK(28, 17)
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_FRAC_OFFSET       0x28
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_FRAC_SHIFT                0
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_FRAC_MASK         GENMASK(23, 0)
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_POSTDIV1_OFFSET   0x28
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_POSTDIV1_SHIFT    28
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_POSTDIV1_MASK     GENMASK(29, 28)
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_PREDIV_OFFSET     0x2c
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_PREDIV_SHIFT      0
> +#define STARFIVE_JH7110_CLK_PLL1_OUT_PREDIV_MASK       GENMASK(5, 0)
> +
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_DACPD_OFFSET      0x2c
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_DACPD_SHIFT       15
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_DACPD_MASK                BIT(15)
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_DSMPD_OFFSET      0x2c
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_DSMPD_SHIFT       16
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_DSMPD_MASK                BIT(16)
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_FBDIV_OFFSET      0x2c
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_FBDIV_SHIFT       17
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_FBDIV_MASK                GENMASK(28, 17)
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_FRAC_OFFSET       0x30
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_FRAC_SHIFT                0
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_FRAC_MASK         GENMASK(23, 0)
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_POSTDIV1_OFFSET   0x30
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_POSTDIV1_SHIFT    28
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_POSTDIV1_MASK     GENMASK(29, 28)
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_PREDIV_OFFSET     0x34
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_PREDIV_SHIFT      0
> +#define STARFIVE_JH7110_CLK_PLL2_OUT_PREDIV_MASK       GENMASK(5, 0)
> +
> +#define JH7110_PLL(_idx, _name, _nums, _val)                   \
> +[_idx] = {                                                     \
> +       .name = _name,                                          \
> +       .offsets = {                                            \
> +               .dacpd = STARFIVE_##_idx##_DACPD_OFFSET,        \
> +               .dsmpd = STARFIVE_##_idx##_DSMPD_OFFSET,        \
> +               .fbdiv = STARFIVE_##_idx##_FBDIV_OFFSET,        \
> +               .frac = STARFIVE_##_idx##_FRAC_OFFSET,          \
> +               .prediv = STARFIVE_##_idx##_PREDIV_OFFSET,      \
> +               .postdiv1 = STARFIVE_##_idx##_POSTDIV1_OFFSET,  \
> +       },                                                      \
> +       .masks = {                                              \
> +               .dacpd = STARFIVE_##_idx##_DACPD_MASK,          \
> +               .dsmpd = STARFIVE_##_idx##_DSMPD_MASK,          \
> +               .fbdiv = STARFIVE_##_idx##_FBDIV_MASK,          \
> +               .frac = STARFIVE_##_idx##_FRAC_MASK,            \
> +               .prediv = STARFIVE_##_idx##_PREDIV_MASK,        \
> +               .postdiv1 = STARFIVE_##_idx##_POSTDIV1_MASK,    \
> +       },                                                      \
> +       .shifts = {                                             \
> +               .dacpd = STARFIVE_##_idx##_DACPD_SHIFT,         \
> +               .dsmpd = STARFIVE_##_idx##_DSMPD_SHIFT,         \
> +               .fbdiv = STARFIVE_##_idx##_FBDIV_SHIFT,         \
> +               .frac = STARFIVE_##_idx##_FRAC_SHIFT,           \
> +               .prediv = STARFIVE_##_idx##_PREDIV_SHIFT,       \
> +               .postdiv1 = STARFIVE_##_idx##_POSTDIV1_SHIFT,   \
> +       },                                                      \
> +       .preset_val_nums = _nums,                               \
> +       .preset_val = _val,                                     \
> +}
> +
> +struct jh7110_pll_syscon_offset {
> +       unsigned int dacpd;
> +       unsigned int dsmpd;
> +       unsigned int fbdiv;
> +       unsigned int frac;
> +       unsigned int prediv;
> +       unsigned int postdiv1;
> +};
> +
> +struct jh7110_pll_syscon_mask {
> +       u32 dacpd;
> +       u32 dsmpd;
> +       u32 fbdiv;
> +       u32 frac;
> +       u32 prediv;
> +       u32 postdiv1;
> +};
> +
> +struct jh7110_pll_syscon_shift {
> +       char dacpd;
> +       char dsmpd;
> +       char fbdiv;
> +       char frac;
> +       char prediv;
> +       char postdiv1;
> +};
> +
> +struct jh7110_pll_syscon_val {
> +       unsigned long freq;
> +       u32 prediv;
> +       u32 fbdiv;
> +       u32 postdiv1;
> +/* Both daxpd and dsmpd set 1 while integer mode */
> +/* Both daxpd and dsmpd set 0 while fraction mode */
> +       u32 dacpd;
> +       u32 dsmpd;
> +/* frac value should be decimals multiplied by 2^24 */
> +       u32 frac;
> +};
> +
> +struct jh7110_pll_syscon_conf {
> +       char *name;
> +       struct jh7110_pll_syscon_offset offsets;
> +       struct jh7110_pll_syscon_mask masks;
> +       struct jh7110_pll_syscon_shift shifts;
> +       unsigned int preset_val_nums;
> +       const struct jh7110_pll_syscon_val *preset_val;
> +};
> +
> +struct jh7110_clk_pll_data {
> +       struct clk_hw hw;
> +       unsigned int idx;
> +       unsigned int freq_select_idx;
> +       struct jh7110_pll_syscon_conf conf;
> +};
> +
> +struct jh7110_clk_pll_priv {
> +       unsigned int pll_nums;
> +       struct device *dev;
> +       struct regmap *syscon_regmap;
> +       struct jh7110_clk_pll_data data[];
> +};
> +
> +enum jh7110_pll0_freq_index {
> +       JH7110_PLL0_FREQ_375 = 0,
> +       JH7110_PLL0_FREQ_500,
> +       JH7110_PLL0_FREQ_625,
> +       JH7110_PLL0_FREQ_750,
> +       JH7110_PLL0_FREQ_875,
> +       JH7110_PLL0_FREQ_1000,
> +       JH7110_PLL0_FREQ_1250,
> +       JH7110_PLL0_FREQ_1375,
> +       JH7110_PLL0_FREQ_1500,
> +       JH7110_PLL0_FREQ_MAX
> +};
> +
> +enum jh7110_pll1_freq_index {
> +       JH7110_PLL1_FREQ_1066 = 0,
> +       JH7110_PLL1_FREQ_1200,
> +       JH7110_PLL1_FREQ_1400,
> +       JH7110_PLL1_FREQ_1600,
> +       JH7110_PLL1_FREQ_MAX
> +};
> +
> +enum jh7110_pll2_freq_index {
> +       JH7110_PLL2_FREQ_1188 = 0,
> +       JH7110_PLL2_FREQ_12288,
> +       JH7110_PLL2_FREQ_MAX
> +};
> +
> +/*
> + * Because the pll frequency is relatively fixed,
> + * it cannot be set arbitrarily, so it needs a specific configuration.
> + * PLL0 frequency should be multiple of 125MHz (USB frequency).
> + */
> +static const struct jh7110_pll_syscon_val
> +       jh7110_pll0_syscon_val_preset[] = {
> +       [JH7110_PLL0_FREQ_375] = {
> +               .freq = 375000000,
> +               .prediv = 8,
> +               .fbdiv = 125,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +       [JH7110_PLL0_FREQ_500] = {
> +               .freq = 500000000,
> +               .prediv = 6,
> +               .fbdiv = 125,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +       [JH7110_PLL0_FREQ_625] = {
> +               .freq = 625000000,
> +               .prediv = 24,
> +               .fbdiv = 625,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +       [JH7110_PLL0_FREQ_750] = {
> +               .freq = 750000000,
> +               .prediv = 4,
> +               .fbdiv = 125,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +       [JH7110_PLL0_FREQ_875] = {
> +               .freq = 875000000,
> +               .prediv = 24,
> +               .fbdiv = 875,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +       [JH7110_PLL0_FREQ_1000] = {
> +               .freq = 1000000000,
> +               .prediv = 3,
> +               .fbdiv = 125,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +       [JH7110_PLL0_FREQ_1250] = {
> +               .freq = 1250000000,
> +               .prediv = 12,
> +               .fbdiv = 625,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +       [JH7110_PLL0_FREQ_1375] = {
> +               .freq = 1375000000,
> +               .prediv = 24,
> +               .fbdiv = 1375,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +       [JH7110_PLL0_FREQ_1500] = {
> +               .freq = 1500000000,
> +               .prediv = 2,
> +               .fbdiv = 125,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +};
> +
> +static const struct jh7110_pll_syscon_val
> +       jh7110_pll1_syscon_val_preset[] = {
> +       [JH7110_PLL1_FREQ_1066] = {
> +               .freq = 1066000000,
> +               .prediv = 12,
> +               .fbdiv = 533,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +       [JH7110_PLL1_FREQ_1200] = {
> +               .freq = 1200000000,
> +               .prediv = 1,
> +               .fbdiv = 50,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +       [JH7110_PLL1_FREQ_1400] = {
> +               .freq = 1400000000,
> +               .prediv = 6,
> +               .fbdiv = 350,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +       [JH7110_PLL1_FREQ_1600] = {
> +               .freq = 1600000000,
> +               .prediv = 3,
> +               .fbdiv = 200,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +};
> +
> +static const struct jh7110_pll_syscon_val
> +       jh7110_pll2_syscon_val_preset[] = {
> +       [JH7110_PLL2_FREQ_1188] = {
> +               .freq = 1188000000,
> +               .prediv = 2,
> +               .fbdiv = 99,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +       [JH7110_PLL2_FREQ_12288] = {
> +               .freq = 1228800000,
> +               .prediv = 5,
> +               .fbdiv = 256,
> +               .postdiv1 = 1,
> +               .dacpd = 1,
> +               .dsmpd = 1,
> +       },
> +};
> +
> +#endif
> --
> 2.25.1

In general this driver is overly generic even though it is a driver
specific to the JH7110 SoC. Rather than try to explain all the ways
you can simplify it, I decided it would be easier to show you:

https://github.com/esmil/linux/commit/9b7f325267c9a760eda6612c7ffbf22366790878

It has all the same functionality, fixes all of the above and saves
more than 100 lines of code, so please use that for your next
revision.

/Emil



More information about the linux-riscv mailing list