diff mbox series

[U-Boot,v9,2/9] clk: sifive: Sync-up WRPLL library with upstream Linux

Message ID 20190625063030.6200-3-anup.patel@wdc.com
State Accepted
Commit c236802696ec2ad3b9110d7db9e601c27e61e8bc
Delegated to: Joe Hershberger
Headers show
Series Update SiFive Unleashed Drivers | expand

Commit Message

Anup Patel June 25, 2019, 6:31 a.m. UTC
Now that SiFive clock driver is merged in upstream Linux, we
sync-up WRPLL library used by SiFive clock driver with upstream
Linux sources.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
---
 drivers/clk/analogbits/wrpll-cln28hpc.c       | 165 ++++++++----------
 drivers/clk/sifive/fu540-prci.c               |  26 +--
 include/linux/clk/analogbits-wrpll-cln28hpc.h |  70 +++-----
 3 files changed, 107 insertions(+), 154 deletions(-)

Comments

Rick Chen July 19, 2019, 5:41 a.m. UTC | #1
> > From: Anup Patel [mailto:Anup.Patel@wdc.com]
> > Sent: Tuesday, June 25, 2019 2:31 PM
> > To: Rick Jian-Zhi Chen(陳建志); Bin Meng; Lukas Auer; Simon Glass
> > Cc: Ramon Fried; Joe Hershberger; Palmer Dabbelt; Paul Walmsley; Troy
> > Benjegerdes; Atish Patra; Alistair Francis; U-Boot Mailing List; Anup Patel
> > Subject: [PATCH v9 2/9] clk: sifive: Sync-up WRPLL library with upstream Linux
> >
> > Now that SiFive clock driver is merged in upstream Linux, we sync-up WRPLL
> > library used by SiFive clock driver with upstream Linux sources.
> >
> > Signed-off-by: Anup Patel <anup.patel@wdc.com>
> > Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
> > ---
> >  drivers/clk/analogbits/wrpll-cln28hpc.c       | 165 ++++++++----------
> >  drivers/clk/sifive/fu540-prci.c               |  26 +--
> >  include/linux/clk/analogbits-wrpll-cln28hpc.h |  70 +++-----
> >  3 files changed, 107 insertions(+), 154 deletions(-)
> >
> > diff --git a/drivers/clk/analogbits/wrpll-cln28hpc.c
> > b/drivers/clk/analogbits/wrpll-cln28hpc.c
> > index 68eb1148b9..776ead319a 100644
> > --- a/drivers/clk/analogbits/wrpll-cln28hpc.c
> > +++ b/drivers/clk/analogbits/wrpll-cln28hpc.c
> > @@ -1,20 +1,9 @@
> >  // SPDX-License-Identifier: GPL-2.0
> >  /*
> > - * Copyright (c) 2019 Western Digital Corporation or its affiliates.
> > - *
> > - * Copyright (C) 2018 SiFive, Inc.
> > + * Copyright (C) 2018-2019 SiFive, Inc.
> >   * Wesley Terpstra
> >   * Paul Walmsley
> >   *
> > - * This program is free software; you can redistribute it and/or modify
> > - * it under the terms of the GNU General Public License version 2 as
> > - * published by the Free Software Foundation.
> > - *
> > - * This program is distributed in the hope that it will be useful,
> > - * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> > - * GNU General Public License for more details.
> > - *
> >   * This library supports configuration parsing and reprogramming of
> >   * the CLN28HPC variant of the Analog Bits Wide Range PLL.  The
> >   * intention is for this library to be reusable for any device that @@ -29,6
> > +18,7 @@
> >   * References:
> >   * - Analog Bits "Wide Range PLL Datasheet", version 2015.10.01
> >   * - SiFive FU540-C000 Manual v1p0, Chapter 7 "Clocking and Reset"
> > + *   https://static.dev.sifive.com/FU540-C000-v1.0.pdf
> >   */
> >
> >  #include <linux/bug.h>
> > @@ -84,40 +74,38 @@
> >   * range selection.
> >   *
> >   * Return: The RANGE value to be presented to the PLL configuration inputs,
> > - *         or -1 upon error.
> > + *         or a negative return code upon error.
> >   */
> >  static int __wrpll_calc_filter_range(unsigned long post_divr_freq)  {
> > -     u8 range;
> > -
> >       if (post_divr_freq < MIN_POST_DIVR_FREQ ||
> >           post_divr_freq > MAX_POST_DIVR_FREQ) {
> >               WARN(1, "%s: post-divider reference freq out of range: %lu",
> >                    __func__, post_divr_freq);
> > -             return -1;
> > +             return -ERANGE;
> >       }
> >
> > -     if (post_divr_freq < 11000000)
> > -             range = 1;
> > -     else if (post_divr_freq < 18000000)
> > -             range = 2;
> > -     else if (post_divr_freq < 30000000)
> > -             range = 3;
> > -     else if (post_divr_freq < 50000000)
> > -             range = 4;
> > -     else if (post_divr_freq < 80000000)
> > -             range = 5;
> > -     else if (post_divr_freq < 130000000)
> > -             range = 6;
> > -     else
> > -             range = 7;
> > -
> > -     return range;
> > +     switch (post_divr_freq) {
> > +     case 0 ... 10999999:
> > +             return 1;
> > +     case 11000000 ... 17999999:
> > +             return 2;
> > +     case 18000000 ... 29999999:
> > +             return 3;
> > +     case 30000000 ... 49999999:
> > +             return 4;
> > +     case 50000000 ... 79999999:
> > +             return 5;
> > +     case 80000000 ... 129999999:
> > +             return 6;
> > +     }
> > +
> > +     return 7;
> >  }
> >
> >  /**
> >   * __wrpll_calc_fbdiv() - return feedback fixed divide value
> > - * @c: ptr to a struct analogbits_wrpll_cfg record to read from
> > + * @c: ptr to a struct wrpll_cfg record to read from
> >   *
> >   * The internal feedback path includes a fixed by-two divider; the
> >   * external feedback path does not.  Return the appropriate divider @@
> > -132,7 +120,7 @@ static int __wrpll_calc_filter_range(unsigned long
> > post_divr_freq)
> >   * Return: 2 if internal feedback is enabled or 1 if external feedback
> >   *         is enabled.
> >   */
> > -static u8 __wrpll_calc_fbdiv(struct analogbits_wrpll_cfg *c)
> > +static u8 __wrpll_calc_fbdiv(const struct wrpll_cfg *c)
> >  {
> >       return (c->flags & WRPLL_FLAGS_INT_FEEDBACK_MASK) ? 2 : 1;  } @@
> > -172,7 +160,7 @@ static u8 __wrpll_calc_divq(u32 target_rate, u64
> > *vco_rate)
> >               *vco_rate = MIN_VCO_FREQ;
> >       } else {
> >               divq = ilog2(s);
> > -             *vco_rate = target_rate << divq;
> > +             *vco_rate = (u64)target_rate << divq;
> >       }
> >
> >  wcd_out:
> > @@ -181,7 +169,7 @@ wcd_out:
> >
> >  /**
> >   * __wrpll_update_parent_rate() - update PLL data when parent rate changes
> > - * @c: ptr to a struct analogbits_wrpll_cfg record to write PLL data to
> > + * @c: ptr to a struct wrpll_cfg record to write PLL data to
> >   * @parent_rate: PLL input refclk rate (pre-R-divider)
> >   *
> >   * Pre-compute some data used by the PLL configuration algorithm when @@
> > -189,46 +177,40 @@ wcd_out:
> >   * computation when the parent rate remains constant - expected to be
> >   * the common case.
> >   *
> > - * Returns: 0 upon success or -1 if the reference clock rate is out of range.
> > + * Returns: 0 upon success or -ERANGE if the reference clock rate is
> > + * out of range.
> >   */
> > -static int __wrpll_update_parent_rate(struct analogbits_wrpll_cfg *c,
> > +static int __wrpll_update_parent_rate(struct wrpll_cfg *c,
> >                                     unsigned long parent_rate)
> >  {
> >       u8 max_r_for_parent;
> >
> >       if (parent_rate > MAX_INPUT_FREQ || parent_rate <
> > MIN_POST_DIVR_FREQ)
> > -             return -1;
> > +             return -ERANGE;
> >
> > -     c->_parent_rate = parent_rate;
> > +     c->parent_rate = parent_rate;
> >       max_r_for_parent = div_u64(parent_rate, MIN_POST_DIVR_FREQ);
> > -     c->_max_r = min_t(u8, MAX_DIVR_DIVISOR, max_r_for_parent);
> > +     c->max_r = min_t(u8, MAX_DIVR_DIVISOR, max_r_for_parent);
> >
> > -     /* Round up */
> > -     c->_init_r = div_u64(parent_rate + MAX_POST_DIVR_FREQ - 1,
> > -                          MAX_POST_DIVR_FREQ);
> > +     c->init_r = DIV_ROUND_UP_ULL(parent_rate, MAX_POST_DIVR_FREQ);
> >
> >       return 0;
> >  }
> >
> > -/*
> > - * Public functions
> > - */
> > -
> >  /**
> > - * analogbits_wrpll_configure() - compute PLL configuration for a target rate
> > - * @c: ptr to a struct analogbits_wrpll_cfg record to write into
> > + * wrpll_configure() - compute PLL configuration for a target rate
> > + * @c: ptr to a struct wrpll_cfg record to write into
> >   * @target_rate: target PLL output clock rate (post-Q-divider)
> >   * @parent_rate: PLL input refclk rate (pre-R-divider)
> >   *
> > - * Given a pointer to a PLL context @c, a desired PLL target output
> > - * rate @target_rate, and a reference clock input rate @parent_rate,
> > - * compute the appropriate PLL signal configuration values.  PLL
> > - * reprogramming is not glitchless, so the caller should switch any
> > - * downstream logic to a different clock source or clock-gate it
> > - * before presenting these values to the PLL configuration signals.
> > + * Compute the appropriate PLL signal configuration values and store
> > + * in PLL context @c.  PLL reprogramming is not glitchless, so the
> > + * caller should switch any downstream logic to a different clock
> > + * source or clock-gate it before presenting these values to the PLL
> > + * configuration signals.
> >   *
> >   * The caller must pass this function a pre-initialized struct
> > - * analogbits_wrpll_cfg record: either initialized to zero (with the
> > + * wrpll_cfg record: either initialized to zero (with the
> >   * exception of the .name and .flags fields) or read from the PLL.
> >   *
> >   * Context: Any context.  Caller must protect the memory pointed to by @c
> > @@ -236,41 +218,26 @@ static int __wrpll_update_parent_rate(struct
> > analogbits_wrpll_cfg *c,
> >   *
> >   * Return: 0 upon success; anything else upon failure.
> >   */
> > -int analogbits_wrpll_configure_for_rate(struct analogbits_wrpll_cfg *c,
> > -                                     u32 target_rate,
> > -                                     unsigned long parent_rate)
> > +int wrpll_configure_for_rate(struct wrpll_cfg *c, u32 target_rate,
> > +                          unsigned long parent_rate)
> >  {
> >       unsigned long ratio;
> >       u64 target_vco_rate, delta, best_delta, f_pre_div, vco, vco_pre;
> > -     u32 best_f, f, post_divr_freq, fbcfg;
> > +     u32 best_f, f, post_divr_freq;
> >       u8 fbdiv, divq, best_r, r;
> > -
> > -     if (!c)
> > -             return -1;
> > +     int range;
> >
> >       if (c->flags == 0) {
> >               WARN(1, "%s called with uninitialized PLL config", __func__);
> > -             return -1;
> > -     }
> > -
> > -     fbcfg = WRPLL_FLAGS_INT_FEEDBACK_MASK |
> > WRPLL_FLAGS_EXT_FEEDBACK_MASK;
> > -     if ((c->flags & fbcfg) == fbcfg) {
> > -             WARN(1, "%s called with invalid PLL config", __func__);
> > -             return -1;
> > -     }
> > -
> > -     if (c->flags == WRPLL_FLAGS_EXT_FEEDBACK_MASK) {
> > -             WARN(1, "%s: external feedback mode not currently supported",
> > -                  __func__);
> > -             return -1;
> > +             return -EINVAL;
> >       }
> >
> >       /* Initialize rounding data if it hasn't been initialized already */
> > -     if (parent_rate != c->_parent_rate) {
> > +     if (parent_rate != c->parent_rate) {
> >               if (__wrpll_update_parent_rate(c, parent_rate)) {
> >                       pr_err("%s: PLL input rate is out of range\n",
> >                              __func__);
> > -                     return -1;
> > +                     return -ERANGE;
> >               }
> >       }
> >
> > @@ -281,11 +248,12 @@ int analogbits_wrpll_configure_for_rate(struct
> > analogbits_wrpll_cfg *c,
> >               c->flags |= WRPLL_FLAGS_BYPASS_MASK;
> >               return 0;
> >       }
> > +
> >       c->flags &= ~WRPLL_FLAGS_BYPASS_MASK;
> >
> >       /* Calculate the Q shift and target VCO rate */
> >       divq = __wrpll_calc_divq(target_rate, &target_vco_rate);
> > -     if (divq == 0)
> > +     if (!divq)
> >               return -1;
> >       c->divq = divq;
> >
> > @@ -301,8 +269,7 @@ int analogbits_wrpll_configure_for_rate(struct
> > analogbits_wrpll_cfg *c,
> >        * Consider all values for R which land within
> >        * [MIN_POST_DIVR_FREQ, MAX_POST_DIVR_FREQ]; prefer smaller R
> >        */
> > -     for (r = c->_init_r; r <= c->_max_r; ++r) {
> > -             /* What is the best F we can pick in this case? */
> > +     for (r = c->init_r; r <= c->max_r; ++r) {
> >               f_pre_div = ratio * r;
> >               f = (f_pre_div + (1 << ROUND_SHIFT)) >> ROUND_SHIFT;
> >               f >>= (fbdiv - 1);
> > @@ -334,46 +301,54 @@ int analogbits_wrpll_configure_for_rate(struct
> > analogbits_wrpll_cfg *c,
> >       post_divr_freq = div_u64(parent_rate, best_r);
> >
> >       /* Pick the best PLL jitter filter */
> > -     c->range = __wrpll_calc_filter_range(post_divr_freq);
> > +     range = __wrpll_calc_filter_range(post_divr_freq);
> > +     if (range < 0)
> > +             return range;
> > +     c->range = range;
> >
> >       return 0;
> >  }
> >
> >  /**
> > - * analogbits_wrpll_calc_output_rate() - calculate the PLL's target output rate
> > - * @c: ptr to a struct analogbits_wrpll_cfg record to read from
> > + * wrpll_calc_output_rate() - calculate the PLL's target output rate
> > + * @c: ptr to a struct wrpll_cfg record to read from
> >   * @parent_rate: PLL refclk rate
> >   *
> >   * Given a pointer to the PLL's current input configuration @c and the
> >   * PLL's input reference clock rate @parent_rate (before the R
> >   * pre-divider), calculate the PLL's output clock rate (after the Q
> > - * post-divider)
> > + * post-divider).
> >   *
> >   * Context: Any context.  Caller must protect the memory pointed to by @c
> >   *          from simultaneous modification.
> >   *
> > - * Return: the PLL's output clock rate, in Hz.
> > + * Return: the PLL's output clock rate, in Hz.  The return value from
> > + *         this function is intended to be convenient to pass directly
> > + *         to the Linux clock framework; thus there is no explicit
> > + *         error return value.
> >   */
> > -unsigned long analogbits_wrpll_calc_output_rate(struct analogbits_wrpll_cfg
> > *c,
> > -                                             unsigned long parent_rate)
> > +unsigned long wrpll_calc_output_rate(const struct wrpll_cfg *c,
> > +                                  unsigned long parent_rate)
> >  {
> >       u8 fbdiv;
> >       u64 n;
> >
> > -     WARN(c->flags & WRPLL_FLAGS_EXT_FEEDBACK_MASK,
> > -          "external feedback mode not yet supported");
> > +     if (c->flags & WRPLL_FLAGS_EXT_FEEDBACK_MASK) {
> > +             WARN(1, "external feedback mode not yet supported");
> > +             return ULONG_MAX;
> > +     }
> >
> >       fbdiv = __wrpll_calc_fbdiv(c);
> >       n = parent_rate * fbdiv * (c->divf + 1);
> > -     n = div_u64(n, (c->divr + 1));
> > +     n = div_u64(n, c->divr + 1);
> >       n >>= c->divq;
> >
> >       return n;
> >  }
> >
> >  /**
> > - * analogbits_wrpll_calc_max_lock_us() - return the time for the PLL to lock
> > - * @c: ptr to a struct analogbits_wrpll_cfg record to read from
> > + * wrpll_calc_max_lock_us() - return the time for the PLL to lock
> > + * @c: ptr to a struct wrpll_cfg record to read from
> >   *
> >   * Return the minimum amount of time (in microseconds) that the caller
> >   * must wait after reprogramming the PLL to ensure that it is locked @@
> > -383,7 +358,7 @@ unsigned long analogbits_wrpll_calc_output_rate(struct
> > analogbits_wrpll_cfg *c,
> >   * Return: the minimum amount of time the caller must wait for the PLL
> >   *         to lock (in microseconds)
> >   */
> > -unsigned int analogbits_wrpll_calc_max_lock_us(struct analogbits_wrpll_cfg
> > *c)
> > +unsigned int wrpll_calc_max_lock_us(const struct wrpll_cfg *c)
> >  {
> >       return MAX_LOCK_US;
> >  }
> > diff --git a/drivers/clk/sifive/fu540-prci.c b/drivers/clk/sifive/fu540-prci.c index
> > 56084db2e6..cdbf35e871 100644
> > --- a/drivers/clk/sifive/fu540-prci.c
> > +++ b/drivers/clk/sifive/fu540-prci.c
> > @@ -174,7 +174,7 @@ struct __prci_data {
> >   * bypass mux is not glitchless.
> >   */
> >  struct __prci_wrpll_data {
> > -     struct analogbits_wrpll_cfg c;
> > +     struct wrpll_cfg c;
> >       void (*bypass)(struct __prci_data *pd);
> >       void (*no_bypass)(struct __prci_data *pd);
> >       u8 cfg0_offs;
> > @@ -244,7 +244,7 @@ static void __prci_writel(u32 v, u32 offs, struct
> > __prci_data *pd)
> >
> >  /**
> >   * __prci_wrpll_unpack() - unpack WRPLL configuration registers into
> > parameters
> > - * @c: ptr to a struct analogbits_wrpll_cfg record to write config into
> > + * @c: ptr to a struct wrpll_cfg record to write config into
> >   * @r: value read from the PRCI PLL configuration register
> >   *
> >   * Given a value @r read from an FU540 PRCI PLL configuration register, @@
> > -256,7 +256,7 @@ static void __prci_writel(u32 v, u32 offs, struct __prci_data
> > *pd)
> >   *
> >   * Context: Any context.
> >   */
> > -static void __prci_wrpll_unpack(struct analogbits_wrpll_cfg *c, u32 r)
> > +static void __prci_wrpll_unpack(struct wrpll_cfg *c, u32 r)
> >  {
> >       u32 v;
> >
> > @@ -287,7 +287,7 @@ static void __prci_wrpll_unpack(struct
> > analogbits_wrpll_cfg *c, u32 r)
> >
> >  /**
> >   * __prci_wrpll_pack() - pack PLL configuration parameters into a register
> > value
> > - * @c: pointer to a struct analogbits_wrpll_cfg record containing the PLL's cfg
> > + * @c: pointer to a struct wrpll_cfg record containing the PLL's cfg
> >   *
> >   * Using a set of WRPLL configuration values pointed to by @c,
> >   * assemble a PRCI PLL configuration register value, and return it to @@
> > -300,7 +300,7 @@ static void __prci_wrpll_unpack(struct analogbits_wrpll_cfg
> > *c, u32 r)
> >   * Returns: a value suitable for writing into a PRCI PLL configuration
> >   *          register
> >   */
> > -static u32 __prci_wrpll_pack(struct analogbits_wrpll_cfg *c)
> > +static u32 __prci_wrpll_pack(struct wrpll_cfg *c)
> >  {
> >       u32 r = 0;
> >
> > @@ -348,11 +348,11 @@ static void __prci_wrpll_read_cfg(struct __prci_data
> > *pd,
> >   */
> >  static void __prci_wrpll_write_cfg(struct __prci_data *pd,
> >                                  struct __prci_wrpll_data *pwd,
> > -                                struct analogbits_wrpll_cfg *c)
> > +                                struct wrpll_cfg *c)
> >  {
> >       __prci_writel(__prci_wrpll_pack(c), pwd->cfg0_offs, pd);
> >
> > -     memcpy(&pwd->c, c, sizeof(struct analogbits_wrpll_cfg));
> > +     memcpy(&pwd->c, c, sizeof(struct wrpll_cfg));
> >  }
> >
> >  /* Core clock mux control */
> > @@ -403,7 +403,7 @@ static unsigned long
> > sifive_fu540_prci_wrpll_recalc_rate(
> >  {
> >       struct __prci_wrpll_data *pwd = pc->pwd;
> >
> > -     return analogbits_wrpll_calc_output_rate(&pwd->c, parent_rate);
> > +     return wrpll_calc_output_rate(&pwd->c, parent_rate);
> >  }
> >
> >  static unsigned long sifive_fu540_prci_wrpll_round_rate(
> > @@ -412,13 +412,13 @@ static unsigned long
> > sifive_fu540_prci_wrpll_round_rate(
> >                                               unsigned long *parent_rate)
> >  {
> >       struct __prci_wrpll_data *pwd = pc->pwd;
> > -     struct analogbits_wrpll_cfg c;
> > +     struct wrpll_cfg c;
> >
> >       memcpy(&c, &pwd->c, sizeof(c));
> >
> > -     analogbits_wrpll_configure_for_rate(&c, rate, *parent_rate);
> > +     wrpll_configure_for_rate(&c, rate, *parent_rate);
> >
> > -     return analogbits_wrpll_calc_output_rate(&c, *parent_rate);
> > +     return wrpll_calc_output_rate(&c, *parent_rate);
> >  }
> >
> >  static int sifive_fu540_prci_wrpll_set_rate(struct __prci_clock *pc, @@
> > -429,7 +429,7 @@ static int sifive_fu540_prci_wrpll_set_rate(struct
> > __prci_clock *pc,
> >       struct __prci_data *pd = pc->pd;
> >       int r;
> >
> > -     r = analogbits_wrpll_configure_for_rate(&pwd->c, rate, parent_rate);
> > +     r = wrpll_configure_for_rate(&pwd->c, rate, parent_rate);
> >       if (r)
> >               return -ERANGE;
> >
> > @@ -438,7 +438,7 @@ static int sifive_fu540_prci_wrpll_set_rate(struct
> > __prci_clock *pc,
> >
> >       __prci_wrpll_write_cfg(pd, pwd, &pwd->c);
> >
> > -     udelay(analogbits_wrpll_calc_max_lock_us(&pwd->c));
> > +     udelay(wrpll_calc_max_lock_us(&pwd->c));
> >
> >       if (pwd->no_bypass)
> >               pwd->no_bypass(pd);
> > diff --git a/include/linux/clk/analogbits-wrpll-cln28hpc.h
> > b/include/linux/clk/analogbits-wrpll-cln28hpc.h
> > index 4432e24749..03279097e1 100644
> > --- a/include/linux/clk/analogbits-wrpll-cln28hpc.h
> > +++ b/include/linux/clk/analogbits-wrpll-cln28hpc.h
> > @@ -1,19 +1,8 @@
> >  /* SPDX-License-Identifier: GPL-2.0 */
> >  /*
> > - * Copyright (c) 2019 Western Digital Corporation or its affiliates.
> > - *
> > - * Copyright (C) 2018 SiFive, Inc.
> > + * Copyright (C) 2018-2019 SiFive, Inc.
> >   * Wesley Terpstra
> >   * Paul Walmsley
> > - *
> > - * This program is free software; you can redistribute it and/or modify
> > - * it under the terms of the GNU General Public License version 2 as
> > - * published by the Free Software Foundation.
> > - *
> > - * This program is distributed in the hope that it will be useful,
> > - * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> > - * GNU General Public License for more details.
> >   */
> >
> >  #ifndef __LINUX_CLK_ANALOGBITS_WRPLL_CLN28HPC_H
> > @@ -25,7 +14,7 @@
> >  #define DIVQ_VALUES                          6
> >
> >  /*
> > - * Bit definitions for struct analogbits_wrpll_cfg.flags
> > + * Bit definitions for struct wrpll_cfg.flags
> >   *
> >   * WRPLL_FLAGS_BYPASS_FLAG: if set, the PLL is either in bypass, or should be
> >   *   programmed to enter bypass
> > @@ -34,10 +23,6 @@
> >   *   feedback mode
> >   * WRPLL_FLAGS_EXT_FEEDBACK_FLAG: if set, the PLL is configured for
> > external
> >   *   feedback mode (not yet supported by this driver)
> > - *
> > - * The flags WRPLL_FLAGS_INT_FEEDBACK_FLAG and
> > WRPLL_FLAGS_EXT_FEEDBACK_FLAG are
> > - * mutually exclusive.  If both bits are set, or both are zero, the struct
> > - * analogbits_wrpll_cfg record is uninitialized or corrupt.
> >   */
> >  #define WRPLL_FLAGS_BYPASS_SHIFT             0
> >  #define WRPLL_FLAGS_BYPASS_MASK
> >       BIT(WRPLL_FLAGS_BYPASS_SHIFT)
> > @@ -49,53 +34,46 @@
> >  #define WRPLL_FLAGS_EXT_FEEDBACK_MASK
> >       BIT(WRPLL_FLAGS_EXT_FEEDBACK_SHIFT)
> >
> >  /**
> > - * struct analogbits_wrpll_cfg - WRPLL configuration values
> > - * @divr: reference divider value (6 bits), as presented to the PLL signals.
> > - * @divf: feedback divider value (9 bits), as presented to the PLL signals.
> > - * @divq: output divider value (3 bits), as presented to the PLL signals.
> > - * @flags: PLL configuration flags.  See above for more information.
> > - * @range: PLL loop filter range.  See below for more information.
> > - * @_output_rate_cache: cached output rates, swept across DIVQ.
> > - * @_parent_rate: PLL refclk rate for which values are valid
> > - * @_max_r: maximum possible R divider value, given @parent_rate
> > - * @_init_r: initial R divider value to start the search from
> > + * struct wrpll_cfg - WRPLL configuration values
> > + * @divr: reference divider value (6 bits), as presented to the PLL
> > + signals
> > + * @divf: feedback divider value (9 bits), as presented to the PLL
> > + signals
> > + * @divq: output divider value (3 bits), as presented to the PLL
> > + signals
> > + * @flags: PLL configuration flags.  See above for more information
> > + * @range: PLL loop filter range.  See below for more information
> > + * @output_rate_cache: cached output rates, swept across DIVQ
> > + * @parent_rate: PLL refclk rate for which values are valid
> > + * @max_r: maximum possible R divider value, given @parent_rate
> > + * @init_r: initial R divider value to start the search from
> >   *
> >   * @divr, @divq, @divq, @range represent what the PLL expects to see
> >   * on its input signals.  Thus @divr and @divf are the actual divisors
> >   * minus one.  @divq is a power-of-two divider; for example, 1 =
> >   * divide-by-2 and 6 = divide-by-64.  0 is an invalid @divq value.
> >   *
> > - * When initially passing a struct analogbits_wrpll_cfg record, the
> > + * When initially passing a struct wrpll_cfg record, the
> >   * record should be zero-initialized with the exception of the @flags
> >   * field.  The only flag bits that need to be set are either
> >   * WRPLL_FLAGS_INT_FEEDBACK or WRPLL_FLAGS_EXT_FEEDBACK.
> > - *
> > - * Field names beginning with an underscore should be considered
> > - * private to the wrpll-cln28hpc.c code.
> >   */
> > -struct analogbits_wrpll_cfg {
> > +struct wrpll_cfg {
> >       u8 divr;
> >       u8 divq;
> >       u8 range;
> >       u8 flags;
> >       u16 divf;
> > -     u32 _output_rate_cache[DIVQ_VALUES];
> > -     unsigned long _parent_rate;
> > -     u8 _max_r;
> > -     u8 _init_r;
> > +/* private: */
> > +     u32 output_rate_cache[DIVQ_VALUES];
> > +     unsigned long parent_rate;
> > +     u8 max_r;
> > +     u8 init_r;
> >  };
> >
> > -/*
> > - * Function prototypes
> > - */
> > -
> > -int analogbits_wrpll_configure_for_rate(struct analogbits_wrpll_cfg *c,
> > -                                     u32 target_rate,
> > -                                     unsigned long parent_rate);
> > +int wrpll_configure_for_rate(struct wrpll_cfg *c, u32 target_rate,
> > +                          unsigned long parent_rate);
> >
> > -unsigned int analogbits_wrpll_calc_max_lock_us(struct analogbits_wrpll_cfg
> > *c);
> > +unsigned int wrpll_calc_max_lock_us(const struct wrpll_cfg *c);
> >
> > -unsigned long analogbits_wrpll_calc_output_rate(struct analogbits_wrpll_cfg
> > *c,
> > -                                             unsigned long parent_rate);
> > +unsigned long wrpll_calc_output_rate(const struct wrpll_cfg *c,
> > +                                  unsigned long parent_rate);
> >
> >  #endif /* __LINUX_CLK_ANALOGBITS_WRPLL_CLN28HPC_H */

Applied to u-boot-riscv/master, thanks!

Rick
diff mbox series

Patch

diff --git a/drivers/clk/analogbits/wrpll-cln28hpc.c b/drivers/clk/analogbits/wrpll-cln28hpc.c
index 68eb1148b9..776ead319a 100644
--- a/drivers/clk/analogbits/wrpll-cln28hpc.c
+++ b/drivers/clk/analogbits/wrpll-cln28hpc.c
@@ -1,20 +1,9 @@ 
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Copyright (c) 2019 Western Digital Corporation or its affiliates.
- *
- * Copyright (C) 2018 SiFive, Inc.
+ * Copyright (C) 2018-2019 SiFive, Inc.
  * Wesley Terpstra
  * Paul Walmsley
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
  * This library supports configuration parsing and reprogramming of
  * the CLN28HPC variant of the Analog Bits Wide Range PLL.  The
  * intention is for this library to be reusable for any device that
@@ -29,6 +18,7 @@ 
  * References:
  * - Analog Bits "Wide Range PLL Datasheet", version 2015.10.01
  * - SiFive FU540-C000 Manual v1p0, Chapter 7 "Clocking and Reset"
+ *   https://static.dev.sifive.com/FU540-C000-v1.0.pdf
  */
 
 #include <linux/bug.h>
@@ -84,40 +74,38 @@ 
  * range selection.
  *
  * Return: The RANGE value to be presented to the PLL configuration inputs,
- *         or -1 upon error.
+ *         or a negative return code upon error.
  */
 static int __wrpll_calc_filter_range(unsigned long post_divr_freq)
 {
-	u8 range;
-
 	if (post_divr_freq < MIN_POST_DIVR_FREQ ||
 	    post_divr_freq > MAX_POST_DIVR_FREQ) {
 		WARN(1, "%s: post-divider reference freq out of range: %lu",
 		     __func__, post_divr_freq);
-		return -1;
+		return -ERANGE;
 	}
 
-	if (post_divr_freq < 11000000)
-		range = 1;
-	else if (post_divr_freq < 18000000)
-		range = 2;
-	else if (post_divr_freq < 30000000)
-		range = 3;
-	else if (post_divr_freq < 50000000)
-		range = 4;
-	else if (post_divr_freq < 80000000)
-		range = 5;
-	else if (post_divr_freq < 130000000)
-		range = 6;
-	else
-		range = 7;
-
-	return range;
+	switch (post_divr_freq) {
+	case 0 ... 10999999:
+		return 1;
+	case 11000000 ... 17999999:
+		return 2;
+	case 18000000 ... 29999999:
+		return 3;
+	case 30000000 ... 49999999:
+		return 4;
+	case 50000000 ... 79999999:
+		return 5;
+	case 80000000 ... 129999999:
+		return 6;
+	}
+
+	return 7;
 }
 
 /**
  * __wrpll_calc_fbdiv() - return feedback fixed divide value
- * @c: ptr to a struct analogbits_wrpll_cfg record to read from
+ * @c: ptr to a struct wrpll_cfg record to read from
  *
  * The internal feedback path includes a fixed by-two divider; the
  * external feedback path does not.  Return the appropriate divider
@@ -132,7 +120,7 @@  static int __wrpll_calc_filter_range(unsigned long post_divr_freq)
  * Return: 2 if internal feedback is enabled or 1 if external feedback
  *         is enabled.
  */
-static u8 __wrpll_calc_fbdiv(struct analogbits_wrpll_cfg *c)
+static u8 __wrpll_calc_fbdiv(const struct wrpll_cfg *c)
 {
 	return (c->flags & WRPLL_FLAGS_INT_FEEDBACK_MASK) ? 2 : 1;
 }
@@ -172,7 +160,7 @@  static u8 __wrpll_calc_divq(u32 target_rate, u64 *vco_rate)
 		*vco_rate = MIN_VCO_FREQ;
 	} else {
 		divq = ilog2(s);
-		*vco_rate = target_rate << divq;
+		*vco_rate = (u64)target_rate << divq;
 	}
 
 wcd_out:
@@ -181,7 +169,7 @@  wcd_out:
 
 /**
  * __wrpll_update_parent_rate() - update PLL data when parent rate changes
- * @c: ptr to a struct analogbits_wrpll_cfg record to write PLL data to
+ * @c: ptr to a struct wrpll_cfg record to write PLL data to
  * @parent_rate: PLL input refclk rate (pre-R-divider)
  *
  * Pre-compute some data used by the PLL configuration algorithm when
@@ -189,46 +177,40 @@  wcd_out:
  * computation when the parent rate remains constant - expected to be
  * the common case.
  *
- * Returns: 0 upon success or -1 if the reference clock rate is out of range.
+ * Returns: 0 upon success or -ERANGE if the reference clock rate is
+ * out of range.
  */
-static int __wrpll_update_parent_rate(struct analogbits_wrpll_cfg *c,
+static int __wrpll_update_parent_rate(struct wrpll_cfg *c,
 				      unsigned long parent_rate)
 {
 	u8 max_r_for_parent;
 
 	if (parent_rate > MAX_INPUT_FREQ || parent_rate < MIN_POST_DIVR_FREQ)
-		return -1;
+		return -ERANGE;
 
-	c->_parent_rate = parent_rate;
+	c->parent_rate = parent_rate;
 	max_r_for_parent = div_u64(parent_rate, MIN_POST_DIVR_FREQ);
-	c->_max_r = min_t(u8, MAX_DIVR_DIVISOR, max_r_for_parent);
+	c->max_r = min_t(u8, MAX_DIVR_DIVISOR, max_r_for_parent);
 
-	/* Round up */
-	c->_init_r = div_u64(parent_rate + MAX_POST_DIVR_FREQ - 1,
-			     MAX_POST_DIVR_FREQ);
+	c->init_r = DIV_ROUND_UP_ULL(parent_rate, MAX_POST_DIVR_FREQ);
 
 	return 0;
 }
 
-/*
- * Public functions
- */
-
 /**
- * analogbits_wrpll_configure() - compute PLL configuration for a target rate
- * @c: ptr to a struct analogbits_wrpll_cfg record to write into
+ * wrpll_configure() - compute PLL configuration for a target rate
+ * @c: ptr to a struct wrpll_cfg record to write into
  * @target_rate: target PLL output clock rate (post-Q-divider)
  * @parent_rate: PLL input refclk rate (pre-R-divider)
  *
- * Given a pointer to a PLL context @c, a desired PLL target output
- * rate @target_rate, and a reference clock input rate @parent_rate,
- * compute the appropriate PLL signal configuration values.  PLL
- * reprogramming is not glitchless, so the caller should switch any
- * downstream logic to a different clock source or clock-gate it
- * before presenting these values to the PLL configuration signals.
+ * Compute the appropriate PLL signal configuration values and store
+ * in PLL context @c.  PLL reprogramming is not glitchless, so the
+ * caller should switch any downstream logic to a different clock
+ * source or clock-gate it before presenting these values to the PLL
+ * configuration signals.
  *
  * The caller must pass this function a pre-initialized struct
- * analogbits_wrpll_cfg record: either initialized to zero (with the
+ * wrpll_cfg record: either initialized to zero (with the
  * exception of the .name and .flags fields) or read from the PLL.
  *
  * Context: Any context.  Caller must protect the memory pointed to by @c
@@ -236,41 +218,26 @@  static int __wrpll_update_parent_rate(struct analogbits_wrpll_cfg *c,
  *
  * Return: 0 upon success; anything else upon failure.
  */
-int analogbits_wrpll_configure_for_rate(struct analogbits_wrpll_cfg *c,
-					u32 target_rate,
-					unsigned long parent_rate)
+int wrpll_configure_for_rate(struct wrpll_cfg *c, u32 target_rate,
+			     unsigned long parent_rate)
 {
 	unsigned long ratio;
 	u64 target_vco_rate, delta, best_delta, f_pre_div, vco, vco_pre;
-	u32 best_f, f, post_divr_freq, fbcfg;
+	u32 best_f, f, post_divr_freq;
 	u8 fbdiv, divq, best_r, r;
-
-	if (!c)
-		return -1;
+	int range;
 
 	if (c->flags == 0) {
 		WARN(1, "%s called with uninitialized PLL config", __func__);
-		return -1;
-	}
-
-	fbcfg = WRPLL_FLAGS_INT_FEEDBACK_MASK | WRPLL_FLAGS_EXT_FEEDBACK_MASK;
-	if ((c->flags & fbcfg) == fbcfg) {
-		WARN(1, "%s called with invalid PLL config", __func__);
-		return -1;
-	}
-
-	if (c->flags == WRPLL_FLAGS_EXT_FEEDBACK_MASK) {
-		WARN(1, "%s: external feedback mode not currently supported",
-		     __func__);
-		return -1;
+		return -EINVAL;
 	}
 
 	/* Initialize rounding data if it hasn't been initialized already */
-	if (parent_rate != c->_parent_rate) {
+	if (parent_rate != c->parent_rate) {
 		if (__wrpll_update_parent_rate(c, parent_rate)) {
 			pr_err("%s: PLL input rate is out of range\n",
 			       __func__);
-			return -1;
+			return -ERANGE;
 		}
 	}
 
@@ -281,11 +248,12 @@  int analogbits_wrpll_configure_for_rate(struct analogbits_wrpll_cfg *c,
 		c->flags |= WRPLL_FLAGS_BYPASS_MASK;
 		return 0;
 	}
+
 	c->flags &= ~WRPLL_FLAGS_BYPASS_MASK;
 
 	/* Calculate the Q shift and target VCO rate */
 	divq = __wrpll_calc_divq(target_rate, &target_vco_rate);
-	if (divq == 0)
+	if (!divq)
 		return -1;
 	c->divq = divq;
 
@@ -301,8 +269,7 @@  int analogbits_wrpll_configure_for_rate(struct analogbits_wrpll_cfg *c,
 	 * Consider all values for R which land within
 	 * [MIN_POST_DIVR_FREQ, MAX_POST_DIVR_FREQ]; prefer smaller R
 	 */
-	for (r = c->_init_r; r <= c->_max_r; ++r) {
-		/* What is the best F we can pick in this case? */
+	for (r = c->init_r; r <= c->max_r; ++r) {
 		f_pre_div = ratio * r;
 		f = (f_pre_div + (1 << ROUND_SHIFT)) >> ROUND_SHIFT;
 		f >>= (fbdiv - 1);
@@ -334,46 +301,54 @@  int analogbits_wrpll_configure_for_rate(struct analogbits_wrpll_cfg *c,
 	post_divr_freq = div_u64(parent_rate, best_r);
 
 	/* Pick the best PLL jitter filter */
-	c->range = __wrpll_calc_filter_range(post_divr_freq);
+	range = __wrpll_calc_filter_range(post_divr_freq);
+	if (range < 0)
+		return range;
+	c->range = range;
 
 	return 0;
 }
 
 /**
- * analogbits_wrpll_calc_output_rate() - calculate the PLL's target output rate
- * @c: ptr to a struct analogbits_wrpll_cfg record to read from
+ * wrpll_calc_output_rate() - calculate the PLL's target output rate
+ * @c: ptr to a struct wrpll_cfg record to read from
  * @parent_rate: PLL refclk rate
  *
  * Given a pointer to the PLL's current input configuration @c and the
  * PLL's input reference clock rate @parent_rate (before the R
  * pre-divider), calculate the PLL's output clock rate (after the Q
- * post-divider)
+ * post-divider).
  *
  * Context: Any context.  Caller must protect the memory pointed to by @c
  *          from simultaneous modification.
  *
- * Return: the PLL's output clock rate, in Hz.
+ * Return: the PLL's output clock rate, in Hz.  The return value from
+ *         this function is intended to be convenient to pass directly
+ *         to the Linux clock framework; thus there is no explicit
+ *         error return value.
  */
-unsigned long analogbits_wrpll_calc_output_rate(struct analogbits_wrpll_cfg *c,
-						unsigned long parent_rate)
+unsigned long wrpll_calc_output_rate(const struct wrpll_cfg *c,
+				     unsigned long parent_rate)
 {
 	u8 fbdiv;
 	u64 n;
 
-	WARN(c->flags & WRPLL_FLAGS_EXT_FEEDBACK_MASK,
-	     "external feedback mode not yet supported");
+	if (c->flags & WRPLL_FLAGS_EXT_FEEDBACK_MASK) {
+		WARN(1, "external feedback mode not yet supported");
+		return ULONG_MAX;
+	}
 
 	fbdiv = __wrpll_calc_fbdiv(c);
 	n = parent_rate * fbdiv * (c->divf + 1);
-	n = div_u64(n, (c->divr + 1));
+	n = div_u64(n, c->divr + 1);
 	n >>= c->divq;
 
 	return n;
 }
 
 /**
- * analogbits_wrpll_calc_max_lock_us() - return the time for the PLL to lock
- * @c: ptr to a struct analogbits_wrpll_cfg record to read from
+ * wrpll_calc_max_lock_us() - return the time for the PLL to lock
+ * @c: ptr to a struct wrpll_cfg record to read from
  *
  * Return the minimum amount of time (in microseconds) that the caller
  * must wait after reprogramming the PLL to ensure that it is locked
@@ -383,7 +358,7 @@  unsigned long analogbits_wrpll_calc_output_rate(struct analogbits_wrpll_cfg *c,
  * Return: the minimum amount of time the caller must wait for the PLL
  *         to lock (in microseconds)
  */
-unsigned int analogbits_wrpll_calc_max_lock_us(struct analogbits_wrpll_cfg *c)
+unsigned int wrpll_calc_max_lock_us(const struct wrpll_cfg *c)
 {
 	return MAX_LOCK_US;
 }
diff --git a/drivers/clk/sifive/fu540-prci.c b/drivers/clk/sifive/fu540-prci.c
index 56084db2e6..cdbf35e871 100644
--- a/drivers/clk/sifive/fu540-prci.c
+++ b/drivers/clk/sifive/fu540-prci.c
@@ -174,7 +174,7 @@  struct __prci_data {
  * bypass mux is not glitchless.
  */
 struct __prci_wrpll_data {
-	struct analogbits_wrpll_cfg c;
+	struct wrpll_cfg c;
 	void (*bypass)(struct __prci_data *pd);
 	void (*no_bypass)(struct __prci_data *pd);
 	u8 cfg0_offs;
@@ -244,7 +244,7 @@  static void __prci_writel(u32 v, u32 offs, struct __prci_data *pd)
 
 /**
  * __prci_wrpll_unpack() - unpack WRPLL configuration registers into parameters
- * @c: ptr to a struct analogbits_wrpll_cfg record to write config into
+ * @c: ptr to a struct wrpll_cfg record to write config into
  * @r: value read from the PRCI PLL configuration register
  *
  * Given a value @r read from an FU540 PRCI PLL configuration register,
@@ -256,7 +256,7 @@  static void __prci_writel(u32 v, u32 offs, struct __prci_data *pd)
  *
  * Context: Any context.
  */
-static void __prci_wrpll_unpack(struct analogbits_wrpll_cfg *c, u32 r)
+static void __prci_wrpll_unpack(struct wrpll_cfg *c, u32 r)
 {
 	u32 v;
 
@@ -287,7 +287,7 @@  static void __prci_wrpll_unpack(struct analogbits_wrpll_cfg *c, u32 r)
 
 /**
  * __prci_wrpll_pack() - pack PLL configuration parameters into a register value
- * @c: pointer to a struct analogbits_wrpll_cfg record containing the PLL's cfg
+ * @c: pointer to a struct wrpll_cfg record containing the PLL's cfg
  *
  * Using a set of WRPLL configuration values pointed to by @c,
  * assemble a PRCI PLL configuration register value, and return it to
@@ -300,7 +300,7 @@  static void __prci_wrpll_unpack(struct analogbits_wrpll_cfg *c, u32 r)
  * Returns: a value suitable for writing into a PRCI PLL configuration
  *          register
  */
-static u32 __prci_wrpll_pack(struct analogbits_wrpll_cfg *c)
+static u32 __prci_wrpll_pack(struct wrpll_cfg *c)
 {
 	u32 r = 0;
 
@@ -348,11 +348,11 @@  static void __prci_wrpll_read_cfg(struct __prci_data *pd,
  */
 static void __prci_wrpll_write_cfg(struct __prci_data *pd,
 				   struct __prci_wrpll_data *pwd,
-				   struct analogbits_wrpll_cfg *c)
+				   struct wrpll_cfg *c)
 {
 	__prci_writel(__prci_wrpll_pack(c), pwd->cfg0_offs, pd);
 
-	memcpy(&pwd->c, c, sizeof(struct analogbits_wrpll_cfg));
+	memcpy(&pwd->c, c, sizeof(struct wrpll_cfg));
 }
 
 /* Core clock mux control */
@@ -403,7 +403,7 @@  static unsigned long sifive_fu540_prci_wrpll_recalc_rate(
 {
 	struct __prci_wrpll_data *pwd = pc->pwd;
 
-	return analogbits_wrpll_calc_output_rate(&pwd->c, parent_rate);
+	return wrpll_calc_output_rate(&pwd->c, parent_rate);
 }
 
 static unsigned long sifive_fu540_prci_wrpll_round_rate(
@@ -412,13 +412,13 @@  static unsigned long sifive_fu540_prci_wrpll_round_rate(
 						unsigned long *parent_rate)
 {
 	struct __prci_wrpll_data *pwd = pc->pwd;
-	struct analogbits_wrpll_cfg c;
+	struct wrpll_cfg c;
 
 	memcpy(&c, &pwd->c, sizeof(c));
 
-	analogbits_wrpll_configure_for_rate(&c, rate, *parent_rate);
+	wrpll_configure_for_rate(&c, rate, *parent_rate);
 
-	return analogbits_wrpll_calc_output_rate(&c, *parent_rate);
+	return wrpll_calc_output_rate(&c, *parent_rate);
 }
 
 static int sifive_fu540_prci_wrpll_set_rate(struct __prci_clock *pc,
@@ -429,7 +429,7 @@  static int sifive_fu540_prci_wrpll_set_rate(struct __prci_clock *pc,
 	struct __prci_data *pd = pc->pd;
 	int r;
 
-	r = analogbits_wrpll_configure_for_rate(&pwd->c, rate, parent_rate);
+	r = wrpll_configure_for_rate(&pwd->c, rate, parent_rate);
 	if (r)
 		return -ERANGE;
 
@@ -438,7 +438,7 @@  static int sifive_fu540_prci_wrpll_set_rate(struct __prci_clock *pc,
 
 	__prci_wrpll_write_cfg(pd, pwd, &pwd->c);
 
-	udelay(analogbits_wrpll_calc_max_lock_us(&pwd->c));
+	udelay(wrpll_calc_max_lock_us(&pwd->c));
 
 	if (pwd->no_bypass)
 		pwd->no_bypass(pd);
diff --git a/include/linux/clk/analogbits-wrpll-cln28hpc.h b/include/linux/clk/analogbits-wrpll-cln28hpc.h
index 4432e24749..03279097e1 100644
--- a/include/linux/clk/analogbits-wrpll-cln28hpc.h
+++ b/include/linux/clk/analogbits-wrpll-cln28hpc.h
@@ -1,19 +1,8 @@ 
 /* SPDX-License-Identifier: GPL-2.0 */
 /*
- * Copyright (c) 2019 Western Digital Corporation or its affiliates.
- *
- * Copyright (C) 2018 SiFive, Inc.
+ * Copyright (C) 2018-2019 SiFive, Inc.
  * Wesley Terpstra
  * Paul Walmsley
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
  */
 
 #ifndef __LINUX_CLK_ANALOGBITS_WRPLL_CLN28HPC_H
@@ -25,7 +14,7 @@ 
 #define DIVQ_VALUES				6
 
 /*
- * Bit definitions for struct analogbits_wrpll_cfg.flags
+ * Bit definitions for struct wrpll_cfg.flags
  *
  * WRPLL_FLAGS_BYPASS_FLAG: if set, the PLL is either in bypass, or should be
  *	programmed to enter bypass
@@ -34,10 +23,6 @@ 
  *	feedback mode
  * WRPLL_FLAGS_EXT_FEEDBACK_FLAG: if set, the PLL is configured for external
  *	feedback mode (not yet supported by this driver)
- *
- * The flags WRPLL_FLAGS_INT_FEEDBACK_FLAG and WRPLL_FLAGS_EXT_FEEDBACK_FLAG are
- * mutually exclusive.  If both bits are set, or both are zero, the struct
- * analogbits_wrpll_cfg record is uninitialized or corrupt.
  */
 #define WRPLL_FLAGS_BYPASS_SHIFT		0
 #define WRPLL_FLAGS_BYPASS_MASK		BIT(WRPLL_FLAGS_BYPASS_SHIFT)
@@ -49,53 +34,46 @@ 
 #define WRPLL_FLAGS_EXT_FEEDBACK_MASK	BIT(WRPLL_FLAGS_EXT_FEEDBACK_SHIFT)
 
 /**
- * struct analogbits_wrpll_cfg - WRPLL configuration values
- * @divr: reference divider value (6 bits), as presented to the PLL signals.
- * @divf: feedback divider value (9 bits), as presented to the PLL signals.
- * @divq: output divider value (3 bits), as presented to the PLL signals.
- * @flags: PLL configuration flags.  See above for more information.
- * @range: PLL loop filter range.  See below for more information.
- * @_output_rate_cache: cached output rates, swept across DIVQ.
- * @_parent_rate: PLL refclk rate for which values are valid
- * @_max_r: maximum possible R divider value, given @parent_rate
- * @_init_r: initial R divider value to start the search from
+ * struct wrpll_cfg - WRPLL configuration values
+ * @divr: reference divider value (6 bits), as presented to the PLL signals
+ * @divf: feedback divider value (9 bits), as presented to the PLL signals
+ * @divq: output divider value (3 bits), as presented to the PLL signals
+ * @flags: PLL configuration flags.  See above for more information
+ * @range: PLL loop filter range.  See below for more information
+ * @output_rate_cache: cached output rates, swept across DIVQ
+ * @parent_rate: PLL refclk rate for which values are valid
+ * @max_r: maximum possible R divider value, given @parent_rate
+ * @init_r: initial R divider value to start the search from
  *
  * @divr, @divq, @divq, @range represent what the PLL expects to see
  * on its input signals.  Thus @divr and @divf are the actual divisors
  * minus one.  @divq is a power-of-two divider; for example, 1 =
  * divide-by-2 and 6 = divide-by-64.  0 is an invalid @divq value.
  *
- * When initially passing a struct analogbits_wrpll_cfg record, the
+ * When initially passing a struct wrpll_cfg record, the
  * record should be zero-initialized with the exception of the @flags
  * field.  The only flag bits that need to be set are either
  * WRPLL_FLAGS_INT_FEEDBACK or WRPLL_FLAGS_EXT_FEEDBACK.
- *
- * Field names beginning with an underscore should be considered
- * private to the wrpll-cln28hpc.c code.
  */
-struct analogbits_wrpll_cfg {
+struct wrpll_cfg {
 	u8 divr;
 	u8 divq;
 	u8 range;
 	u8 flags;
 	u16 divf;
-	u32 _output_rate_cache[DIVQ_VALUES];
-	unsigned long _parent_rate;
-	u8 _max_r;
-	u8 _init_r;
+/* private: */
+	u32 output_rate_cache[DIVQ_VALUES];
+	unsigned long parent_rate;
+	u8 max_r;
+	u8 init_r;
 };
 
-/*
- * Function prototypes
- */
-
-int analogbits_wrpll_configure_for_rate(struct analogbits_wrpll_cfg *c,
-					u32 target_rate,
-					unsigned long parent_rate);
+int wrpll_configure_for_rate(struct wrpll_cfg *c, u32 target_rate,
+			     unsigned long parent_rate);
 
-unsigned int analogbits_wrpll_calc_max_lock_us(struct analogbits_wrpll_cfg *c);
+unsigned int wrpll_calc_max_lock_us(const struct wrpll_cfg *c);
 
-unsigned long analogbits_wrpll_calc_output_rate(struct analogbits_wrpll_cfg *c,
-						unsigned long parent_rate);
+unsigned long wrpll_calc_output_rate(const struct wrpll_cfg *c,
+				     unsigned long parent_rate);
 
 #endif /* __LINUX_CLK_ANALOGBITS_WRPLL_CLN28HPC_H */