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References: <20230704064610.292603-1-xingyu.wu@starfivetech.com> <20230704064610.292603-5-xingyu.wu@starfivetech.com>
In-Reply-To: <20230704064610.292603-5-xingyu.wu@starfivetech.com>
From:   Emil Renner Berthing <emil.renner.berthing@canonical.com>
Date:   Thu, 13 Jul 2023 14:37:49 +0200
Message-ID: <CAJM55Z_bi-2o4eP8rT4V8zp0D5rvF3WzBRt8ALMjukodgmC_PQ@mail.gmail.com>
Subject: Re: [RESEND PATCH v6 4/7] clk: starfive: Add StarFive JH7110 PLL
 clock driver
To:     Xingyu Wu <xingyu.wu@starfivetech.com>
Cc:     linux-riscv@lists.infradead.org, devicetree@vger.kernel.org,
        Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        Conor Dooley <conor@kernel.org>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Hal Feng <hal.feng@starfivetech.com>,
        William Qiu <william.qiu@starfivetech.com>,
        linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Tue, 4 Jul 2023 at 08:49, Xingyu Wu <xingyu.wu@starfivetech.com> wrote:
>
> Add driver for the StarFive JH7110 PLL clock controller
> and they work by reading and setting syscon registers.
>
> Co-developed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
> Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
> Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com>

Thanks for using my changes! I'll add my r-b for Conor, but since I'm
also a co-developer it's fine to leave it out if you resubmit.
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>

> ---
>  MAINTAINERS                                   |   6 +
>  drivers/clk/starfive/Kconfig                  |   8 +
>  drivers/clk/starfive/Makefile                 |   1 +
>  .../clk/starfive/clk-starfive-jh7110-pll.c    | 507 ++++++++++++++++++
>  4 files changed, 522 insertions(+)
>  create mode 100644 drivers/clk/starfive/clk-starfive-jh7110-pll.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 58ba04bd0bc8..b59b4d217991 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -20127,6 +20127,12 @@ 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@starfivetech.com>
> +S:     Supported
> +F:     Documentation/devicetree/bindings/clock/starfive,jh7110-pll.yaml
> +F:     drivers/clk/starfive/clk-starfive-jh7110-pll.*
> +
>  STARFIVE JH7110 SYSCON
>  M:     William Qiu <william.qiu@starfivetech.com>
>  M:     Xingyu Wu <xingyu.wu@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..b10c142d456d
> --- /dev/null
> +++ b/drivers/clk/starfive/clk-starfive-jh7110-pll.c
> @@ -0,0 +1,507 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * StarFive JH7110 PLL Clock Generator Driver
> + *
> + * Copyright (C) 2023 StarFive Technology Co., Ltd.
> + * Copyright (C) 2023 Emil Renner Berthing <emil.renner.berthing@canonical.com>
> + *
> + * 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 2^postdiv1[1:0], eg. 1, 2, 4 or 8.
> + */
> +
> +#include <linux/bits.h>
> +#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>
> +
> +/* this driver expects a 24MHz input frequency from the oscillator */
> +#define JH7110_PLL_OSC_RATE            24000000UL
> +
> +#define JH7110_PLL0_PD_OFFSET          0x18
> +#define JH7110_PLL0_DACPD_SHIFT                24
> +#define JH7110_PLL0_DACPD_MASK         BIT(24)
> +#define JH7110_PLL0_DSMPD_SHIFT                25
> +#define JH7110_PLL0_DSMPD_MASK         BIT(25)
> +#define JH7110_PLL0_FBDIV_OFFSET       0x1c
> +#define JH7110_PLL0_FBDIV_SHIFT                0
> +#define JH7110_PLL0_FBDIV_MASK         GENMASK(11, 0)
> +#define JH7110_PLL0_FRAC_OFFSET                0x20
> +#define JH7110_PLL0_PREDIV_OFFSET      0x24
> +
> +#define JH7110_PLL1_PD_OFFSET          0x24
> +#define JH7110_PLL1_DACPD_SHIFT                15
> +#define JH7110_PLL1_DACPD_MASK         BIT(15)
> +#define JH7110_PLL1_DSMPD_SHIFT                16
> +#define JH7110_PLL1_DSMPD_MASK         BIT(16)
> +#define JH7110_PLL1_FBDIV_OFFSET       0x24
> +#define JH7110_PLL1_FBDIV_SHIFT                17
> +#define JH7110_PLL1_FBDIV_MASK         GENMASK(28, 17)
> +#define JH7110_PLL1_FRAC_OFFSET                0x28
> +#define JH7110_PLL1_PREDIV_OFFSET      0x2c
> +
> +#define JH7110_PLL2_PD_OFFSET          0x2c
> +#define JH7110_PLL2_DACPD_SHIFT                15
> +#define JH7110_PLL2_DACPD_MASK         BIT(15)
> +#define JH7110_PLL2_DSMPD_SHIFT                16
> +#define JH7110_PLL2_DSMPD_MASK         BIT(16)
> +#define JH7110_PLL2_FBDIV_OFFSET       0x2c
> +#define JH7110_PLL2_FBDIV_SHIFT                17
> +#define JH7110_PLL2_FBDIV_MASK         GENMASK(28, 17)
> +#define JH7110_PLL2_FRAC_OFFSET                0x30
> +#define JH7110_PLL2_PREDIV_OFFSET      0x34
> +
> +#define JH7110_PLL_FRAC_SHIFT          0
> +#define JH7110_PLL_FRAC_MASK           GENMASK(23, 0)
> +#define JH7110_PLL_POSTDIV1_SHIFT      28
> +#define JH7110_PLL_POSTDIV1_MASK       GENMASK(29, 28)
> +#define JH7110_PLL_PREDIV_SHIFT                0
> +#define JH7110_PLL_PREDIV_MASK         GENMASK(5, 0)
> +
> +enum jh7110_pll_mode {
> +       JH7110_PLL_MODE_FRACTION,
> +       JH7110_PLL_MODE_INTEGER,
> +};
> +
> +struct jh7110_pll_preset {
> +       unsigned long freq;
> +       u32 frac;               /* frac value should be decimals multiplied by 2^24 */
> +       unsigned fbdiv    : 12; /* fbdiv value should be 8 to 4095 */
> +       unsigned prediv   :  6;
> +       unsigned postdiv1 :  2;
> +       unsigned mode     :  1;
> +};
> +
> +struct jh7110_pll_info {
> +       char *name;
> +       const struct jh7110_pll_preset *presets;
> +       unsigned int npresets;
> +       struct {
> +               unsigned int pd;
> +               unsigned int fbdiv;
> +               unsigned int frac;
> +               unsigned int prediv;
> +       } offsets;
> +       struct {
> +               u32 dacpd;
> +               u32 dsmpd;
> +               u32 fbdiv;
> +       } masks;
> +       struct {
> +               char dacpd;
> +               char dsmpd;
> +               char fbdiv;
> +       } shifts;
> +};
> +
> +#define _JH7110_PLL(_idx, _name, _presets)                             \
> +       [_idx] = {                                                      \
> +               .name = _name,                                          \
> +               .presets = _presets,                                    \
> +               .npresets = ARRAY_SIZE(_presets),                       \
> +               .offsets = {                                            \
> +                       .pd = JH7110_PLL##_idx##_PD_OFFSET,             \
> +                       .fbdiv = JH7110_PLL##_idx##_FBDIV_OFFSET,       \
> +                       .frac = JH7110_PLL##_idx##_FRAC_OFFSET,         \
> +                       .prediv = JH7110_PLL##_idx##_PREDIV_OFFSET,     \
> +               },                                                      \
> +               .masks = {                                              \
> +                       .dacpd = JH7110_PLL##_idx##_DACPD_MASK,         \
> +                       .dsmpd = JH7110_PLL##_idx##_DSMPD_MASK,         \
> +                       .fbdiv = JH7110_PLL##_idx##_FBDIV_MASK,         \
> +               },                                                      \
> +               .shifts = {                                             \
> +                       .dacpd = JH7110_PLL##_idx##_DACPD_SHIFT,        \
> +                       .dsmpd = JH7110_PLL##_idx##_DSMPD_SHIFT,        \
> +                       .fbdiv = JH7110_PLL##_idx##_FBDIV_SHIFT,        \
> +               },                                                      \
> +       }
> +#define JH7110_PLL(idx, name, presets) _JH7110_PLL(idx, name, presets)
> +
> +struct jh7110_pll_data {
> +       struct clk_hw hw;
> +       unsigned int idx;
> +};
> +
> +struct jh7110_pll_priv {
> +       struct device *dev;
> +       struct regmap *regmap;
> +       struct jh7110_pll_data pll[JH7110_PLLCLK_END];
> +};
> +
> +struct jh7110_pll_regvals {
> +       u32 dacpd;
> +       u32 dsmpd;
> +       u32 fbdiv;
> +       u32 frac;
> +       u32 postdiv1;
> +       u32 prediv;
> +};
> +
> +/*
> + * 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_preset jh7110_pll0_presets[] = {
> +       {
> +               .freq = 375000000,
> +               .fbdiv = 125,
> +               .prediv = 8,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       }, {
> +               .freq = 500000000,
> +               .fbdiv = 125,
> +               .prediv = 6,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       }, {
> +               .freq = 625000000,
> +               .fbdiv = 625,
> +               .prediv = 24,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       }, {
> +               .freq = 750000000,
> +               .fbdiv = 125,
> +               .prediv = 4,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       }, {
> +               .freq = 875000000,
> +               .fbdiv = 875,
> +               .prediv = 24,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       }, {
> +               .freq = 1000000000,
> +               .fbdiv = 125,
> +               .prediv = 3,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       }, {
> +               .freq = 1250000000,
> +               .fbdiv = 625,
> +               .prediv = 12,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       }, {
> +               .freq = 1375000000,
> +               .fbdiv = 1375,
> +               .prediv = 24,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       }, {
> +               .freq = 1500000000,
> +               .fbdiv = 125,
> +               .prediv = 2,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       },
> +};
> +
> +static const struct jh7110_pll_preset jh7110_pll1_presets[] = {
> +       {
> +               .freq = 1066000000,
> +               .fbdiv = 533,
> +               .prediv = 12,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       }, {
> +               .freq = 1200000000,
> +               .fbdiv = 50,
> +               .prediv = 1,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       }, {
> +               .freq = 1400000000,
> +               .fbdiv = 350,
> +               .prediv = 6,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       }, {
> +               .freq = 1600000000,
> +               .fbdiv = 200,
> +               .prediv = 3,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       },
> +};
> +
> +static const struct jh7110_pll_preset jh7110_pll2_presets[] = {
> +       {
> +               .freq = 1188000000,
> +               .fbdiv = 99,
> +               .prediv = 2,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       }, {
> +               .freq = 1228800000,
> +               .fbdiv = 256,
> +               .prediv = 5,
> +               .postdiv1 = 0,
> +               .mode = JH7110_PLL_MODE_INTEGER,
> +       },
> +};
> +
> +static const struct jh7110_pll_info jh7110_plls[JH7110_PLLCLK_END] = {
> +       JH7110_PLL(JH7110_CLK_PLL0_OUT, "pll0_out", jh7110_pll0_presets),
> +       JH7110_PLL(JH7110_CLK_PLL1_OUT, "pll1_out", jh7110_pll1_presets),
> +       JH7110_PLL(JH7110_CLK_PLL2_OUT, "pll2_out", jh7110_pll2_presets),
> +};
> +
> +static struct jh7110_pll_data *jh7110_pll_data_from(struct clk_hw *hw)
> +{
> +       return container_of(hw, struct jh7110_pll_data, hw);
> +}
> +
> +static struct jh7110_pll_priv *jh7110_pll_priv_from(struct jh7110_pll_data *pll)
> +{
> +       return container_of(pll, struct jh7110_pll_priv, pll[pll->idx]);
> +}
> +
> +static void jh7110_pll_regvals_get(struct regmap *regmap,
> +                                  const struct jh7110_pll_info *info,
> +                                  struct jh7110_pll_regvals *ret)
> +{
> +       u32 val;
> +
> +       regmap_read(regmap, info->offsets.pd, &val);
> +       ret->dacpd = (val & info->masks.dacpd) >> info->shifts.dacpd;
> +       ret->dsmpd = (val & info->masks.dsmpd) >> info->shifts.dsmpd;
> +
> +       regmap_read(regmap, info->offsets.fbdiv, &val);
> +       ret->fbdiv = (val & info->masks.fbdiv) >> info->shifts.fbdiv;
> +
> +       regmap_read(regmap, info->offsets.frac, &val);
> +       ret->frac = (val & JH7110_PLL_FRAC_MASK) >> JH7110_PLL_FRAC_SHIFT;
> +       ret->postdiv1 = (val & JH7110_PLL_POSTDIV1_MASK) >> JH7110_PLL_POSTDIV1_SHIFT;
> +
> +       regmap_read(regmap, info->offsets.prediv, &val);
> +       ret->prediv = (val & JH7110_PLL_PREDIV_MASK) >> JH7110_PLL_PREDIV_SHIFT;
> +}
> +
> +static unsigned long jh7110_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
> +{
> +       struct jh7110_pll_data *pll = jh7110_pll_data_from(hw);
> +       struct jh7110_pll_priv *priv = jh7110_pll_priv_from(pll);
> +       struct jh7110_pll_regvals val;
> +       unsigned long rate;
> +
> +       jh7110_pll_regvals_get(priv->regmap, &jh7110_plls[pll->idx], &val);
> +
> +       /*
> +        * dacpd = dsmpd = 0: fraction mode
> +        * dacpd = dsmpd = 1: integer mode, frac value ignored
> +        *
> +        * rate = parent * (fbdiv + frac/2^24) / prediv / 2^postdiv1
> +        *      = (parent * fbdiv + parent * frac / 2^24) / (prediv * 2^postdiv1)
> +        */
> +       if (val.dacpd == 0 && val.dsmpd == 0)
> +               rate = parent_rate * val.frac / (1UL << 24);
> +       else if (val.dacpd == 1 && val.dsmpd == 1)
> +               rate = 0;
> +       else
> +               return 0;
> +
> +       rate += parent_rate * val.fbdiv;
> +       rate /= val.prediv << val.postdiv1;
> +
> +       return rate;
> +}
> +
> +static int jh7110_pll_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
> +{
> +       struct jh7110_pll_data *pll = jh7110_pll_data_from(hw);
> +       const struct jh7110_pll_info *info = &jh7110_plls[pll->idx];
> +       const struct jh7110_pll_preset *selected = &info->presets[0];
> +       unsigned int idx;
> +
> +       /* if the parent rate doesn't match our expectations the presets won't work */
> +       if (req->best_parent_rate != JH7110_PLL_OSC_RATE) {
> +               req->rate = jh7110_pll_recalc_rate(hw, req->best_parent_rate);
> +               return 0;
> +       }
> +
> +       /* find highest rate lower or equal to the requested rate */
> +       for (idx = 1; idx < info->npresets; idx++) {
> +               const struct jh7110_pll_preset *val = &info->presets[idx];
> +
> +               if (req->rate < val->freq)
> +                       break;
> +
> +               selected = val;
> +       }
> +
> +       req->rate = selected->freq;
> +       return 0;
> +}
> +
> +static int jh7110_pll_set_rate(struct clk_hw *hw, unsigned long rate,
> +                              unsigned long parent_rate)
> +{
> +       struct jh7110_pll_data *pll = jh7110_pll_data_from(hw);
> +       struct jh7110_pll_priv *priv = jh7110_pll_priv_from(pll);
> +       const struct jh7110_pll_info *info = &jh7110_plls[pll->idx];
> +       const struct jh7110_pll_preset *val;
> +       unsigned int idx;
> +
> +       /* if the parent rate doesn't match our expectations the presets won't work */
> +       if (parent_rate != JH7110_PLL_OSC_RATE)
> +               return -EINVAL;
> +
> +       for (idx = 0, val = &info->presets[0]; idx < info->npresets; idx++, val++) {
> +               if (val->freq == rate)
> +                       goto found;
> +       }
> +       return -EINVAL;
> +
> +found:
> +       if (val->mode == JH7110_PLL_MODE_FRACTION)
> +               regmap_update_bits(priv->regmap, info->offsets.frac, JH7110_PLL_FRAC_MASK,
> +                                  val->frac << JH7110_PLL_FRAC_SHIFT);
> +
> +       regmap_update_bits(priv->regmap, info->offsets.pd, info->masks.dacpd,
> +                          (u32)val->mode << info->shifts.dacpd);
> +       regmap_update_bits(priv->regmap, info->offsets.pd, info->masks.dsmpd,
> +                          (u32)val->mode << info->shifts.dsmpd);
> +       regmap_update_bits(priv->regmap, info->offsets.prediv, JH7110_PLL_PREDIV_MASK,
> +                          (u32)val->prediv << JH7110_PLL_PREDIV_SHIFT);
> +       regmap_update_bits(priv->regmap, info->offsets.fbdiv, info->masks.fbdiv,
> +                          val->fbdiv << info->shifts.fbdiv);
> +       regmap_update_bits(priv->regmap, info->offsets.frac, JH7110_PLL_POSTDIV1_MASK,
> +                          (u32)val->postdiv1 << JH7110_PLL_POSTDIV1_SHIFT);
> +
> +       return 0;
> +}
> +
> +#ifdef CONFIG_DEBUG_FS
> +static int jh7110_pll_registers_read(struct seq_file *s, void *unused)
> +{
> +       struct jh7110_pll_data *pll = s->private;
> +       struct jh7110_pll_priv *priv = jh7110_pll_priv_from(pll);
> +       struct jh7110_pll_regvals val;
> +
> +       jh7110_pll_regvals_get(priv->regmap, &jh7110_plls[pll->idx], &val);
> +
> +       seq_printf(s, "fbdiv=%u\n"
> +                     "frac=%u\n"
> +                     "prediv=%u\n"
> +                     "postdiv1=%u\n"
> +                     "dacpd=%u\n"
> +                     "dsmpd=%u\n",
> +                     val.fbdiv, val.frac, val.prediv, val.postdiv1,
> +                     val.dacpd, val.dsmpd);
> +
> +       return 0;
> +}
> +
> +static int jh7110_pll_registers_open(struct inode *inode, struct file *f)
> +{
> +       return single_open(f, jh7110_pll_registers_read, inode->i_private);
> +}
> +
> +static const struct file_operations jh7110_pll_registers_ops = {
> +       .owner = THIS_MODULE,
> +       .open = jh7110_pll_registers_open,
> +       .release = single_release,
> +       .read = seq_read,
> +       .llseek = seq_lseek
> +};
> +
> +static void jh7110_pll_debug_init(struct clk_hw *hw, struct dentry *dentry)
> +{
> +       struct jh7110_pll_data *pll = jh7110_pll_data_from(hw);
> +
> +       debugfs_create_file("registers", 0400, dentry, pll,
> +                           &jh7110_pll_registers_ops);
> +}
> +#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_pll_priv *priv = data;
> +       unsigned int idx = clkspec->args[0];
> +
> +       if (idx < JH7110_PLLCLK_END)
> +               return &priv->pll[idx].hw;
> +
> +       return ERR_PTR(-EINVAL);
> +}
> +
> +static int jh7110_pll_probe(struct platform_device *pdev)
> +{
> +       struct jh7110_pll_priv *priv;
> +       unsigned int idx;
> +       int ret;
> +
> +       priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> +       if (!priv)
> +               return -ENOMEM;
> +
> +       priv->dev = &pdev->dev;
> +       priv->regmap = syscon_node_to_regmap(priv->dev->of_node->parent);
> +       if (IS_ERR(priv->regmap))
> +               return PTR_ERR(priv->regmap);
> +
> +       for (idx = 0; idx < JH7110_PLLCLK_END; idx++) {
> +               struct clk_parent_data parents = {
> +                       .index = 0,
> +               };
> +               struct clk_init_data init = {
> +                       .name = jh7110_plls[idx].name,
> +                       .ops = &jh7110_pll_ops,
> +                       .parent_data = &parents,
> +                       .num_parents = 1,
> +                       .flags = 0,
> +               };
> +               struct jh7110_pll_data *pll = &priv->pll[idx];
> +
> +               pll->hw.init = &init;
> +               pll->idx = idx;
> +
> +               ret = devm_clk_hw_register(&pdev->dev, &pll->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" },
> +       { /* 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);
> --
> 2.25.1
>