clk: change clk_ops' ->determine_rate() prototype

[mirror_ubuntu-zesty-kernel.git] / drivers / clk / sunxi / clk-sunxi.c

/*
 * Copyright 2013 Emilio López
 *
 * Emilio López <emilio@elopez.com.ar>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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.
 */

#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/reset-controller.h>
#include <linux/spinlock.h>
#include <linux/log2.h>

#include "clk-factors.h"

static DEFINE_SPINLOCK(clk_lock);

/**
 * sun6i_a31_ahb1_clk_setup() - Setup function for a31 ahb1 composite clk
 */

#define SUN6I_AHB1_MAX_PARENTS          4
#define SUN6I_AHB1_MUX_PARENT_PLL6      3
#define SUN6I_AHB1_MUX_SHIFT            12
/* un-shifted mask is what mux_clk expects */
#define SUN6I_AHB1_MUX_MASK             0x3
#define SUN6I_AHB1_MUX_GET_PARENT(reg)  ((reg >> SUN6I_AHB1_MUX_SHIFT) & \
                                         SUN6I_AHB1_MUX_MASK)

#define SUN6I_AHB1_DIV_SHIFT            4
#define SUN6I_AHB1_DIV_MASK             (0x3 << SUN6I_AHB1_DIV_SHIFT)
#define SUN6I_AHB1_DIV_GET(reg)         ((reg & SUN6I_AHB1_DIV_MASK) >> \
                                                SUN6I_AHB1_DIV_SHIFT)
#define SUN6I_AHB1_DIV_SET(reg, div)    ((reg & ~SUN6I_AHB1_DIV_MASK) | \
                                                (div << SUN6I_AHB1_DIV_SHIFT))
#define SUN6I_AHB1_PLL6_DIV_SHIFT       6
#define SUN6I_AHB1_PLL6_DIV_MASK        (0x3 << SUN6I_AHB1_PLL6_DIV_SHIFT)
#define SUN6I_AHB1_PLL6_DIV_GET(reg)    ((reg & SUN6I_AHB1_PLL6_DIV_MASK) >> \
                                                SUN6I_AHB1_PLL6_DIV_SHIFT)
#define SUN6I_AHB1_PLL6_DIV_SET(reg, div) ((reg & ~SUN6I_AHB1_PLL6_DIV_MASK) | \
                                                (div << SUN6I_AHB1_PLL6_DIV_SHIFT))

struct sun6i_ahb1_clk {
        struct clk_hw hw;
        void __iomem *reg;
};

#define to_sun6i_ahb1_clk(_hw) container_of(_hw, struct sun6i_ahb1_clk, hw)

static unsigned long sun6i_ahb1_clk_recalc_rate(struct clk_hw *hw,
                                                unsigned long parent_rate)
{
        struct sun6i_ahb1_clk *ahb1 = to_sun6i_ahb1_clk(hw);
        unsigned long rate;
        u32 reg;

        /* Fetch the register value */
        reg = readl(ahb1->reg);

        /* apply pre-divider first if parent is pll6 */
        if (SUN6I_AHB1_MUX_GET_PARENT(reg) == SUN6I_AHB1_MUX_PARENT_PLL6)
                parent_rate /= SUN6I_AHB1_PLL6_DIV_GET(reg) + 1;

        /* clk divider */
        rate = parent_rate >> SUN6I_AHB1_DIV_GET(reg);

        return rate;
}

static long sun6i_ahb1_clk_round(unsigned long rate, u8 *divp, u8 *pre_divp,
                                 u8 parent, unsigned long parent_rate)
{
        u8 div, calcp, calcm = 1;

        /*
         * clock can only divide, so we will never be able to achieve
         * frequencies higher than the parent frequency
         */
        if (parent_rate && rate > parent_rate)
                rate = parent_rate;

        div = DIV_ROUND_UP(parent_rate, rate);

        /* calculate pre-divider if parent is pll6 */
        if (parent == SUN6I_AHB1_MUX_PARENT_PLL6) {
                if (div < 4)
                        calcp = 0;
                else if (div / 2 < 4)
                        calcp = 1;
                else if (div / 4 < 4)
                        calcp = 2;
                else
                        calcp = 3;

                calcm = DIV_ROUND_UP(div, 1 << calcp);
        } else {
                calcp = __roundup_pow_of_two(div);
                calcp = calcp > 3 ? 3 : calcp;
        }

        /* we were asked to pass back divider values */
        if (divp) {
                *divp = calcp;
                *pre_divp = calcm - 1;
        }

        return (parent_rate / calcm) >> calcp;
}

static int sun6i_ahb1_clk_determine_rate(struct clk_hw *hw,
                                         struct clk_rate_request *req)
{
        struct clk *clk = hw->clk, *parent, *best_parent = NULL;
        int i, num_parents;
        unsigned long parent_rate, best = 0, child_rate, best_child_rate = 0;

        /* find the parent that can help provide the fastest rate <= rate */
        num_parents = __clk_get_num_parents(clk);
        for (i = 0; i < num_parents; i++) {
                parent = clk_get_parent_by_index(clk, i);
                if (!parent)
                        continue;
                if (__clk_get_flags(clk) & CLK_SET_RATE_PARENT)
                        parent_rate = __clk_round_rate(parent, req->rate);
                else
                        parent_rate = __clk_get_rate(parent);

                child_rate = sun6i_ahb1_clk_round(req->rate, NULL, NULL, i,
                                                  parent_rate);

                if (child_rate <= req->rate && child_rate > best_child_rate) {
                        best_parent = parent;
                        best = parent_rate;
                        best_child_rate = child_rate;
                }
        }

        if (best_parent)
                req->best_parent_hw = __clk_get_hw(best_parent);
        req->best_parent_rate = best;
        req->rate = best_child_rate;

        return 0;
}

static int sun6i_ahb1_clk_set_rate(struct clk_hw *hw, unsigned long rate,
                                   unsigned long parent_rate)
{
        struct sun6i_ahb1_clk *ahb1 = to_sun6i_ahb1_clk(hw);
        unsigned long flags;
        u8 div, pre_div, parent;
        u32 reg;

        spin_lock_irqsave(&clk_lock, flags);

        reg = readl(ahb1->reg);

        /* need to know which parent is used to apply pre-divider */
        parent = SUN6I_AHB1_MUX_GET_PARENT(reg);
        sun6i_ahb1_clk_round(rate, &div, &pre_div, parent, parent_rate);

        reg = SUN6I_AHB1_DIV_SET(reg, div);
        reg = SUN6I_AHB1_PLL6_DIV_SET(reg, pre_div);
        writel(reg, ahb1->reg);

        spin_unlock_irqrestore(&clk_lock, flags);

        return 0;
}

static const struct clk_ops sun6i_ahb1_clk_ops = {
        .determine_rate = sun6i_ahb1_clk_determine_rate,
        .recalc_rate    = sun6i_ahb1_clk_recalc_rate,
        .set_rate       = sun6i_ahb1_clk_set_rate,
};

static void __init sun6i_ahb1_clk_setup(struct device_node *node)
{
        struct clk *clk;
        struct sun6i_ahb1_clk *ahb1;
        struct clk_mux *mux;
        const char *clk_name = node->name;
        const char *parents[SUN6I_AHB1_MAX_PARENTS];
        void __iomem *reg;
        int i = 0;

        reg = of_io_request_and_map(node, 0, of_node_full_name(node));
        if (IS_ERR(reg))
                return;

        /* we have a mux, we will have >1 parents */
        while (i < SUN6I_AHB1_MAX_PARENTS &&
               (parents[i] = of_clk_get_parent_name(node, i)) != NULL)
                i++;

        of_property_read_string(node, "clock-output-names", &clk_name);

        ahb1 = kzalloc(sizeof(struct sun6i_ahb1_clk), GFP_KERNEL);
        if (!ahb1)
                return;

        mux = kzalloc(sizeof(struct clk_mux), GFP_KERNEL);
        if (!mux) {
                kfree(ahb1);
                return;
        }

        /* set up clock properties */
        mux->reg = reg;
        mux->shift = SUN6I_AHB1_MUX_SHIFT;
        mux->mask = SUN6I_AHB1_MUX_MASK;
        mux->lock = &clk_lock;
        ahb1->reg = reg;

        clk = clk_register_composite(NULL, clk_name, parents, i,
                                     &mux->hw, &clk_mux_ops,
                                     &ahb1->hw, &sun6i_ahb1_clk_ops,
                                     NULL, NULL, 0);

        if (!IS_ERR(clk)) {
                of_clk_add_provider(node, of_clk_src_simple_get, clk);
                clk_register_clkdev(clk, clk_name, NULL);
        }
}
CLK_OF_DECLARE(sun6i_a31_ahb1, "allwinner,sun6i-a31-ahb1-clk", sun6i_ahb1_clk_setup);

/* Maximum number of parents our clocks have */
#define SUNXI_MAX_PARENTS       5

/**
 * sun4i_get_pll1_factors() - calculates n, k, m, p factors for PLL1
 * PLL1 rate is calculated as follows
 * rate = (parent_rate * n * (k + 1) >> p) / (m + 1);
 * parent_rate is always 24Mhz
 */

static void sun4i_get_pll1_factors(u32 *freq, u32 parent_rate,
                                   u8 *n, u8 *k, u8 *m, u8 *p)
{
        u8 div;

        /* Normalize value to a 6M multiple */
        div = *freq / 6000000;
        *freq = 6000000 * div;

        /* we were called to round the frequency, we can now return */
        if (n == NULL)
                return;

        /* m is always zero for pll1 */
        *m = 0;

        /* k is 1 only on these cases */
        if (*freq >= 768000000 || *freq == 42000000 || *freq == 54000000)
                *k = 1;
        else
                *k = 0;

        /* p will be 3 for divs under 10 */
        if (div < 10)
                *p = 3;

        /* p will be 2 for divs between 10 - 20 and odd divs under 32 */
        else if (div < 20 || (div < 32 && (div & 1)))
                *p = 2;

        /* p will be 1 for even divs under 32, divs under 40 and odd pairs
         * of divs between 40-62 */
        else if (div < 40 || (div < 64 && (div & 2)))
                *p = 1;

        /* any other entries have p = 0 */
        else
                *p = 0;

        /* calculate a suitable n based on k and p */
        div <<= *p;
        div /= (*k + 1);
        *n = div / 4;
}

/**
 * sun6i_a31_get_pll1_factors() - calculates n, k and m factors for PLL1
 * PLL1 rate is calculated as follows
 * rate = parent_rate * (n + 1) * (k + 1) / (m + 1);
 * parent_rate should always be 24MHz
 */
static void sun6i_a31_get_pll1_factors(u32 *freq, u32 parent_rate,
                                       u8 *n, u8 *k, u8 *m, u8 *p)
{
        /*
         * We can operate only on MHz, this will make our life easier
         * later.
         */
        u32 freq_mhz = *freq / 1000000;
        u32 parent_freq_mhz = parent_rate / 1000000;

        /*
         * Round down the frequency to the closest multiple of either
         * 6 or 16
         */
        u32 round_freq_6 = round_down(freq_mhz, 6);
        u32 round_freq_16 = round_down(freq_mhz, 16);

        if (round_freq_6 > round_freq_16)
                freq_mhz = round_freq_6;
        else
                freq_mhz = round_freq_16;

        *freq = freq_mhz * 1000000;

        /*
         * If the factors pointer are null, we were just called to
         * round down the frequency.
         * Exit.
         */
        if (n == NULL)
                return;

        /* If the frequency is a multiple of 32 MHz, k is always 3 */
        if (!(freq_mhz % 32))
                *k = 3;
        /* If the frequency is a multiple of 9 MHz, k is always 2 */
        else if (!(freq_mhz % 9))
                *k = 2;
        /* If the frequency is a multiple of 8 MHz, k is always 1 */
        else if (!(freq_mhz % 8))
                *k = 1;
        /* Otherwise, we don't use the k factor */
        else
                *k = 0;

        /*
         * If the frequency is a multiple of 2 but not a multiple of
         * 3, m is 3. This is the first time we use 6 here, yet we
         * will use it on several other places.
         * We use this number because it's the lowest frequency we can
         * generate (with n = 0, k = 0, m = 3), so every other frequency
         * somehow relates to this frequency.
         */
        if ((freq_mhz % 6) == 2 || (freq_mhz % 6) == 4)
                *m = 2;
        /*
         * If the frequency is a multiple of 6MHz, but the factor is
         * odd, m will be 3
         */
        else if ((freq_mhz / 6) & 1)
                *m = 3;
        /* Otherwise, we end up with m = 1 */
        else
                *m = 1;

        /* Calculate n thanks to the above factors we already got */
        *n = freq_mhz * (*m + 1) / ((*k + 1) * parent_freq_mhz) - 1;

        /*
         * If n end up being outbound, and that we can still decrease
         * m, do it.
         */
        if ((*n + 1) > 31 && (*m + 1) > 1) {
                *n = (*n + 1) / 2 - 1;
                *m = (*m + 1) / 2 - 1;
        }
}

/**
 * sun8i_a23_get_pll1_factors() - calculates n, k, m, p factors for PLL1
 * PLL1 rate is calculated as follows
 * rate = (parent_rate * (n + 1) * (k + 1) >> p) / (m + 1);
 * parent_rate is always 24Mhz
 */

static void sun8i_a23_get_pll1_factors(u32 *freq, u32 parent_rate,
                                   u8 *n, u8 *k, u8 *m, u8 *p)
{
        u8 div;

        /* Normalize value to a 6M multiple */
        div = *freq / 6000000;
        *freq = 6000000 * div;

        /* we were called to round the frequency, we can now return */
        if (n == NULL)
                return;

        /* m is always zero for pll1 */
        *m = 0;

        /* k is 1 only on these cases */
        if (*freq >= 768000000 || *freq == 42000000 || *freq == 54000000)
                *k = 1;
        else
                *k = 0;

        /* p will be 2 for divs under 20 and odd divs under 32 */
        if (div < 20 || (div < 32 && (div & 1)))
                *p = 2;

        /* p will be 1 for even divs under 32, divs under 40 and odd pairs
         * of divs between 40-62 */
        else if (div < 40 || (div < 64 && (div & 2)))
                *p = 1;

        /* any other entries have p = 0 */
        else
                *p = 0;

        /* calculate a suitable n based on k and p */
        div <<= *p;
        div /= (*k + 1);
        *n = div / 4 - 1;
}

/**
 * sun4i_get_pll5_factors() - calculates n, k factors for PLL5
 * PLL5 rate is calculated as follows
 * rate = parent_rate * n * (k + 1)
 * parent_rate is always 24Mhz
 */

static void sun4i_get_pll5_factors(u32 *freq, u32 parent_rate,
                                   u8 *n, u8 *k, u8 *m, u8 *p)
{
        u8 div;

        /* Normalize value to a parent_rate multiple (24M) */
        div = *freq / parent_rate;
        *freq = parent_rate * div;

        /* we were called to round the frequency, we can now return */
        if (n == NULL)
                return;

        if (div < 31)
                *k = 0;
        else if (div / 2 < 31)
                *k = 1;
        else if (div / 3 < 31)
                *k = 2;
        else
                *k = 3;

        *n = DIV_ROUND_UP(div, (*k+1));
}

/**
 * sun6i_a31_get_pll6_factors() - calculates n, k factors for A31 PLL6x2
 * PLL6x2 rate is calculated as follows
 * rate = parent_rate * (n + 1) * (k + 1)
 * parent_rate is always 24Mhz
 */

static void sun6i_a31_get_pll6_factors(u32 *freq, u32 parent_rate,
                                       u8 *n, u8 *k, u8 *m, u8 *p)
{
        u8 div;

        /* Normalize value to a parent_rate multiple (24M) */
        div = *freq / parent_rate;
        *freq = parent_rate * div;

        /* we were called to round the frequency, we can now return */
        if (n == NULL)
                return;

        *k = div / 32;
        if (*k > 3)
                *k = 3;

        *n = DIV_ROUND_UP(div, (*k+1)) - 1;
}

/**
 * sun5i_a13_get_ahb_factors() - calculates m, p factors for AHB
 * AHB rate is calculated as follows
 * rate = parent_rate >> p
 */

static void sun5i_a13_get_ahb_factors(u32 *freq, u32 parent_rate,
                                       u8 *n, u8 *k, u8 *m, u8 *p)
{
        u32 div;

        /* divide only */
        if (parent_rate < *freq)
                *freq = parent_rate;

        /*
         * user manual says valid speed is 8k ~ 276M, but tests show it
         * can work at speeds up to 300M, just after reparenting to pll6
         */
        if (*freq < 8000)
                *freq = 8000;
        if (*freq > 300000000)
                *freq = 300000000;

        div = order_base_2(DIV_ROUND_UP(parent_rate, *freq));

        /* p = 0 ~ 3 */
        if (div > 3)
                div = 3;

        *freq = parent_rate >> div;

        /* we were called to round the frequency, we can now return */
        if (p == NULL)
                return;

        *p = div;
}

/**
 * sun4i_get_apb1_factors() - calculates m, p factors for APB1
 * APB1 rate is calculated as follows
 * rate = (parent_rate >> p) / (m + 1);
 */

static void sun4i_get_apb1_factors(u32 *freq, u32 parent_rate,
                                   u8 *n, u8 *k, u8 *m, u8 *p)
{
        u8 calcm, calcp;

        if (parent_rate < *freq)
                *freq = parent_rate;

        parent_rate = DIV_ROUND_UP(parent_rate, *freq);

        /* Invalid rate! */
        if (parent_rate > 32)
                return;

        if (parent_rate <= 4)
                calcp = 0;
        else if (parent_rate <= 8)
                calcp = 1;
        else if (parent_rate <= 16)
                calcp = 2;
        else
                calcp = 3;

        calcm = (parent_rate >> calcp) - 1;

        *freq = (parent_rate >> calcp) / (calcm + 1);

        /* we were called to round the frequency, we can now return */
        if (n == NULL)
                return;

        *m = calcm;
        *p = calcp;
}




/**
 * sun7i_a20_get_out_factors() - calculates m, p factors for CLK_OUT_A/B
 * CLK_OUT rate is calculated as follows
 * rate = (parent_rate >> p) / (m + 1);
 */

static void sun7i_a20_get_out_factors(u32 *freq, u32 parent_rate,
                                      u8 *n, u8 *k, u8 *m, u8 *p)
{
        u8 div, calcm, calcp;

        /* These clocks can only divide, so we will never be able to achieve
         * frequencies higher than the parent frequency */
        if (*freq > parent_rate)
                *freq = parent_rate;

        div = DIV_ROUND_UP(parent_rate, *freq);

        if (div < 32)
                calcp = 0;
        else if (div / 2 < 32)
                calcp = 1;
        else if (div / 4 < 32)
                calcp = 2;
        else
                calcp = 3;

        calcm = DIV_ROUND_UP(div, 1 << calcp);

        *freq = (parent_rate >> calcp) / calcm;

        /* we were called to round the frequency, we can now return */
        if (n == NULL)
                return;

        *m = calcm - 1;
        *p = calcp;
}

/**
 * sunxi_factors_clk_setup() - Setup function for factor clocks
 */

static struct clk_factors_config sun4i_pll1_config = {
        .nshift = 8,
        .nwidth = 5,
        .kshift = 4,
        .kwidth = 2,
        .mshift = 0,
        .mwidth = 2,
        .pshift = 16,
        .pwidth = 2,
};

static struct clk_factors_config sun6i_a31_pll1_config = {
        .nshift = 8,
        .nwidth = 5,
        .kshift = 4,
        .kwidth = 2,
        .mshift = 0,
        .mwidth = 2,
        .n_start = 1,
};

static struct clk_factors_config sun8i_a23_pll1_config = {
        .nshift = 8,
        .nwidth = 5,
        .kshift = 4,
        .kwidth = 2,
        .mshift = 0,
        .mwidth = 2,
        .pshift = 16,
        .pwidth = 2,
        .n_start = 1,
};

static struct clk_factors_config sun4i_pll5_config = {
        .nshift = 8,
        .nwidth = 5,
        .kshift = 4,
        .kwidth = 2,
};

static struct clk_factors_config sun6i_a31_pll6_config = {
        .nshift = 8,
        .nwidth = 5,
        .kshift = 4,
        .kwidth = 2,
        .n_start = 1,
};

static struct clk_factors_config sun5i_a13_ahb_config = {
        .pshift = 4,
        .pwidth = 2,
};

static struct clk_factors_config sun4i_apb1_config = {
        .mshift = 0,
        .mwidth = 5,
        .pshift = 16,
        .pwidth = 2,
};

/* user manual says "n" but it's really "p" */
static struct clk_factors_config sun7i_a20_out_config = {
        .mshift = 8,
        .mwidth = 5,
        .pshift = 20,
        .pwidth = 2,
};

static const struct factors_data sun4i_pll1_data __initconst = {
        .enable = 31,
        .table = &sun4i_pll1_config,
        .getter = sun4i_get_pll1_factors,
};

static const struct factors_data sun6i_a31_pll1_data __initconst = {
        .enable = 31,
        .table = &sun6i_a31_pll1_config,
        .getter = sun6i_a31_get_pll1_factors,
};

static const struct factors_data sun8i_a23_pll1_data __initconst = {
        .enable = 31,
        .table = &sun8i_a23_pll1_config,
        .getter = sun8i_a23_get_pll1_factors,
};

static const struct factors_data sun7i_a20_pll4_data __initconst = {
        .enable = 31,
        .table = &sun4i_pll5_config,
        .getter = sun4i_get_pll5_factors,
};

static const struct factors_data sun4i_pll5_data __initconst = {
        .enable = 31,
        .table = &sun4i_pll5_config,
        .getter = sun4i_get_pll5_factors,
        .name = "pll5",
};

static const struct factors_data sun4i_pll6_data __initconst = {
        .enable = 31,
        .table = &sun4i_pll5_config,
        .getter = sun4i_get_pll5_factors,
        .name = "pll6",
};

static const struct factors_data sun6i_a31_pll6_data __initconst = {
        .enable = 31,
        .table = &sun6i_a31_pll6_config,
        .getter = sun6i_a31_get_pll6_factors,
        .name = "pll6x2",
};

static const struct factors_data sun5i_a13_ahb_data __initconst = {
        .mux = 6,
        .muxmask = BIT(1) | BIT(0),
        .table = &sun5i_a13_ahb_config,
        .getter = sun5i_a13_get_ahb_factors,
};

static const struct factors_data sun4i_apb1_data __initconst = {
        .mux = 24,
        .muxmask = BIT(1) | BIT(0),
        .table = &sun4i_apb1_config,
        .getter = sun4i_get_apb1_factors,
};

static const struct factors_data sun7i_a20_out_data __initconst = {
        .enable = 31,
        .mux = 24,
        .muxmask = BIT(1) | BIT(0),
        .table = &sun7i_a20_out_config,
        .getter = sun7i_a20_get_out_factors,
};

static struct clk * __init sunxi_factors_clk_setup(struct device_node *node,
                                                   const struct factors_data *data)
{
        void __iomem *reg;

        reg = of_iomap(node, 0);
        if (!reg) {
                pr_err("Could not get registers for factors-clk: %s\n",
                       node->name);
                return NULL;
        }

        return sunxi_factors_register(node, data, &clk_lock, reg);
}



/**
 * sunxi_mux_clk_setup() - Setup function for muxes
 */

#define SUNXI_MUX_GATE_WIDTH    2

struct mux_data {
        u8 shift;
};

static const struct mux_data sun4i_cpu_mux_data __initconst = {
        .shift = 16,
};

static const struct mux_data sun6i_a31_ahb1_mux_data __initconst = {
        .shift = 12,
};

static void __init sunxi_mux_clk_setup(struct device_node *node,
                                       struct mux_data *data)
{
        struct clk *clk;
        const char *clk_name = node->name;
        const char *parents[SUNXI_MAX_PARENTS];
        void __iomem *reg;
        int i = 0;

        reg = of_iomap(node, 0);

        while (i < SUNXI_MAX_PARENTS &&
               (parents[i] = of_clk_get_parent_name(node, i)) != NULL)
                i++;

        of_property_read_string(node, "clock-output-names", &clk_name);

        clk = clk_register_mux(NULL, clk_name, parents, i,
                               CLK_SET_RATE_PARENT, reg,
                               data->shift, SUNXI_MUX_GATE_WIDTH,
                               0, &clk_lock);

        if (clk) {
                of_clk_add_provider(node, of_clk_src_simple_get, clk);
                clk_register_clkdev(clk, clk_name, NULL);
        }
}



/**
 * sunxi_divider_clk_setup() - Setup function for simple divider clocks
 */

struct div_data {
        u8      shift;
        u8      pow;
        u8      width;
        const struct clk_div_table *table;
};

static const struct div_data sun4i_axi_data __initconst = {
        .shift  = 0,
        .pow    = 0,
        .width  = 2,
};

static const struct clk_div_table sun8i_a23_axi_table[] __initconst = {
        { .val = 0, .div = 1 },
        { .val = 1, .div = 2 },
        { .val = 2, .div = 3 },
        { .val = 3, .div = 4 },
        { .val = 4, .div = 4 },
        { .val = 5, .div = 4 },
        { .val = 6, .div = 4 },
        { .val = 7, .div = 4 },
        { } /* sentinel */
};

static const struct div_data sun8i_a23_axi_data __initconst = {
        .width  = 3,
        .table  = sun8i_a23_axi_table,
};

static const struct div_data sun4i_ahb_data __initconst = {
        .shift  = 4,
        .pow    = 1,
        .width  = 2,
};

static const struct clk_div_table sun4i_apb0_table[] __initconst = {
        { .val = 0, .div = 2 },
        { .val = 1, .div = 2 },
        { .val = 2, .div = 4 },
        { .val = 3, .div = 8 },
        { } /* sentinel */
};

static const struct div_data sun4i_apb0_data __initconst = {
        .shift  = 8,
        .pow    = 1,
        .width  = 2,
        .table  = sun4i_apb0_table,
};

static void __init sunxi_divider_clk_setup(struct device_node *node,
                                           struct div_data *data)
{
        struct clk *clk;
        const char *clk_name = node->name;
        const char *clk_parent;
        void __iomem *reg;

        reg = of_iomap(node, 0);

        clk_parent = of_clk_get_parent_name(node, 0);

        of_property_read_string(node, "clock-output-names", &clk_name);

        clk = clk_register_divider_table(NULL, clk_name, clk_parent, 0,
                                         reg, data->shift, data->width,
                                         data->pow ? CLK_DIVIDER_POWER_OF_TWO : 0,
                                         data->table, &clk_lock);
        if (clk) {
                of_clk_add_provider(node, of_clk_src_simple_get, clk);
                clk_register_clkdev(clk, clk_name, NULL);
        }
}



/**
 * sunxi_gates_clk_setup() - Setup function for leaf gates on clocks
 */

#define SUNXI_GATES_MAX_SIZE    64

struct gates_data {
        DECLARE_BITMAP(mask, SUNXI_GATES_MAX_SIZE);
};

static const struct gates_data sun4i_axi_gates_data __initconst = {
        .mask = {1},
};

static const struct gates_data sun4i_ahb_gates_data __initconst = {
        .mask = {0x7F77FFF, 0x14FB3F},
};

static const struct gates_data sun5i_a10s_ahb_gates_data __initconst = {
        .mask = {0x147667e7, 0x185915},
};

static const struct gates_data sun5i_a13_ahb_gates_data __initconst = {
        .mask = {0x107067e7, 0x185111},
};

static const struct gates_data sun6i_a31_ahb1_gates_data __initconst = {
        .mask = {0xEDFE7F62, 0x794F931},
};

static const struct gates_data sun7i_a20_ahb_gates_data __initconst = {
        .mask = { 0x12f77fff, 0x16ff3f },
};

static const struct gates_data sun8i_a23_ahb1_gates_data __initconst = {
        .mask = {0x25386742, 0x2505111},
};

static const struct gates_data sun9i_a80_ahb0_gates_data __initconst = {
        .mask = {0xF5F12B},
};

static const struct gates_data sun9i_a80_ahb1_gates_data __initconst = {
        .mask = {0x1E20003},
};

static const struct gates_data sun9i_a80_ahb2_gates_data __initconst = {
        .mask = {0x9B7},
};

static const struct gates_data sun4i_apb0_gates_data __initconst = {
        .mask = {0x4EF},
};

static const struct gates_data sun5i_a10s_apb0_gates_data __initconst = {
        .mask = {0x469},
};

static const struct gates_data sun5i_a13_apb0_gates_data __initconst = {
        .mask = {0x61},
};

static const struct gates_data sun7i_a20_apb0_gates_data __initconst = {
        .mask = { 0x4ff },
};

static const struct gates_data sun9i_a80_apb0_gates_data __initconst = {
        .mask = {0xEB822},
};

static const struct gates_data sun4i_apb1_gates_data __initconst = {
        .mask = {0xFF00F7},
};

static const struct gates_data sun5i_a10s_apb1_gates_data __initconst = {
        .mask = {0xf0007},
};

static const struct gates_data sun5i_a13_apb1_gates_data __initconst = {
        .mask = {0xa0007},
};

static const struct gates_data sun6i_a31_apb1_gates_data __initconst = {
        .mask = {0x3031},
};

static const struct gates_data sun8i_a23_apb1_gates_data __initconst = {
        .mask = {0x3021},
};

static const struct gates_data sun6i_a31_apb2_gates_data __initconst = {
        .mask = {0x3F000F},
};

static const struct gates_data sun7i_a20_apb1_gates_data __initconst = {
        .mask = { 0xff80ff },
};

static const struct gates_data sun9i_a80_apb1_gates_data __initconst = {
        .mask = {0x3F001F},
};

static const struct gates_data sun8i_a23_apb2_gates_data __initconst = {
        .mask = {0x1F0007},
};

static void __init sunxi_gates_clk_setup(struct device_node *node,
                                         struct gates_data *data)
{
        struct clk_onecell_data *clk_data;
        const char *clk_parent;
        const char *clk_name;
        void __iomem *reg;
        int qty;
        int i = 0;
        int j = 0;

        reg = of_iomap(node, 0);

        clk_parent = of_clk_get_parent_name(node, 0);

        /* Worst-case size approximation and memory allocation */
        qty = find_last_bit(data->mask, SUNXI_GATES_MAX_SIZE);
        clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
        if (!clk_data)
                return;
        clk_data->clks = kzalloc((qty+1) * sizeof(struct clk *), GFP_KERNEL);
        if (!clk_data->clks) {
                kfree(clk_data);
                return;
        }

        for_each_set_bit(i, data->mask, SUNXI_GATES_MAX_SIZE) {
                of_property_read_string_index(node, "clock-output-names",
                                              j, &clk_name);

                clk_data->clks[i] = clk_register_gate(NULL, clk_name,
                                                      clk_parent, 0,
                                                      reg + 4 * (i/32), i % 32,
                                                      0, &clk_lock);
                WARN_ON(IS_ERR(clk_data->clks[i]));
                clk_register_clkdev(clk_data->clks[i], clk_name, NULL);

                j++;
        }

        /* Adjust to the real max */
        clk_data->clk_num = i;

        of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
}



/**
 * sunxi_divs_clk_setup() helper data
 */

#define SUNXI_DIVS_MAX_QTY      4
#define SUNXI_DIVISOR_WIDTH     2

struct divs_data {
        const struct factors_data *factors; /* data for the factor clock */
        int ndivs; /* number of outputs */
        /*
         * List of outputs. Refer to the diagram for sunxi_divs_clk_setup():
         * self or base factor clock refers to the output from the pll
         * itself. The remaining refer to fixed or configurable divider
         * outputs.
         */
        struct {
                u8 self; /* is it the base factor clock? (only one) */
                u8 fixed; /* is it a fixed divisor? if not... */
                struct clk_div_table *table; /* is it a table based divisor? */
                u8 shift; /* otherwise it's a normal divisor with this shift */
                u8 pow;   /* is it power-of-two based? */
                u8 gate;  /* is it independently gateable? */
        } div[SUNXI_DIVS_MAX_QTY];
};

static struct clk_div_table pll6_sata_tbl[] = {
        { .val = 0, .div = 6, },
        { .val = 1, .div = 12, },
        { .val = 2, .div = 18, },
        { .val = 3, .div = 24, },
        { } /* sentinel */
};

static const struct divs_data pll5_divs_data __initconst = {
        .factors = &sun4i_pll5_data,
        .ndivs = 2,
        .div = {
                { .shift = 0, .pow = 0, }, /* M, DDR */
                { .shift = 16, .pow = 1, }, /* P, other */
                /* No output for the base factor clock */
        }
};

static const struct divs_data pll6_divs_data __initconst = {
        .factors = &sun4i_pll6_data,
        .ndivs = 4,
        .div = {
                { .shift = 0, .table = pll6_sata_tbl, .gate = 14 }, /* M, SATA */
                { .fixed = 2 }, /* P, other */
                { .self = 1 }, /* base factor clock, 2x */
                { .fixed = 4 }, /* pll6 / 4, used as ahb input */
        }
};

static const struct divs_data sun6i_a31_pll6_divs_data __initconst = {
        .factors = &sun6i_a31_pll6_data,
        .ndivs = 2,
        .div = {
                { .fixed = 2 }, /* normal output */
                { .self = 1 }, /* base factor clock, 2x */
        }
};

/**
 * sunxi_divs_clk_setup() - Setup function for leaf divisors on clocks
 *
 * These clocks look something like this
 *            ________________________
 *           |         ___divisor 1---|----> to consumer
 * parent >--|  pll___/___divisor 2---|----> to consumer
 *           |        \_______________|____> to consumer
 *           |________________________|
 */

static void __init sunxi_divs_clk_setup(struct device_node *node,
                                        struct divs_data *data)
{
        struct clk_onecell_data *clk_data;
        const char *parent;
        const char *clk_name;
        struct clk **clks, *pclk;
        struct clk_hw *gate_hw, *rate_hw;
        const struct clk_ops *rate_ops;
        struct clk_gate *gate = NULL;
        struct clk_fixed_factor *fix_factor;
        struct clk_divider *divider;
        void __iomem *reg;
        int ndivs = SUNXI_DIVS_MAX_QTY, i = 0;
        int flags, clkflags;

        /* if number of children known, use it */
        if (data->ndivs)
                ndivs = data->ndivs;

        /* Set up factor clock that we will be dividing */
        pclk = sunxi_factors_clk_setup(node, data->factors);
        parent = __clk_get_name(pclk);

        reg = of_iomap(node, 0);

        clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
        if (!clk_data)
                return;

        clks = kcalloc(ndivs, sizeof(*clks), GFP_KERNEL);
        if (!clks)
                goto free_clkdata;

        clk_data->clks = clks;

        /* It's not a good idea to have automatic reparenting changing
         * our RAM clock! */
        clkflags = !strcmp("pll5", parent) ? 0 : CLK_SET_RATE_PARENT;

        for (i = 0; i < ndivs; i++) {
                if (of_property_read_string_index(node, "clock-output-names",
                                                  i, &clk_name) != 0)
                        break;

                /* If this is the base factor clock, only update clks */
                if (data->div[i].self) {
                        clk_data->clks[i] = pclk;
                        continue;
                }

                gate_hw = NULL;
                rate_hw = NULL;
                rate_ops = NULL;

                /* If this leaf clock can be gated, create a gate */
                if (data->div[i].gate) {
                        gate = kzalloc(sizeof(*gate), GFP_KERNEL);
                        if (!gate)
                                goto free_clks;

                        gate->reg = reg;
                        gate->bit_idx = data->div[i].gate;
                        gate->lock = &clk_lock;

                        gate_hw = &gate->hw;
                }

                /* Leaves can be fixed or configurable divisors */
                if (data->div[i].fixed) {
                        fix_factor = kzalloc(sizeof(*fix_factor), GFP_KERNEL);
                        if (!fix_factor)
                                goto free_gate;

                        fix_factor->mult = 1;
                        fix_factor->div = data->div[i].fixed;

                        rate_hw = &fix_factor->hw;
                        rate_ops = &clk_fixed_factor_ops;
                } else {
                        divider = kzalloc(sizeof(*divider), GFP_KERNEL);
                        if (!divider)
                                goto free_gate;

                        flags = data->div[i].pow ? CLK_DIVIDER_POWER_OF_TWO : 0;

                        divider->reg = reg;
                        divider->shift = data->div[i].shift;
                        divider->width = SUNXI_DIVISOR_WIDTH;
                        divider->flags = flags;
                        divider->lock = &clk_lock;
                        divider->table = data->div[i].table;

                        rate_hw = &divider->hw;
                        rate_ops = &clk_divider_ops;
                }

                /* Wrap the (potential) gate and the divisor on a composite
                 * clock to unify them */
                clks[i] = clk_register_composite(NULL, clk_name, &parent, 1,
                                                 NULL, NULL,
                                                 rate_hw, rate_ops,
                                                 gate_hw, &clk_gate_ops,
                                                 clkflags);

                WARN_ON(IS_ERR(clk_data->clks[i]));
                clk_register_clkdev(clks[i], clk_name, NULL);
        }

        /* Adjust to the real max */
        clk_data->clk_num = i;

        of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);

        return;

free_gate:
        kfree(gate);
free_clks:
        kfree(clks);
free_clkdata:
        kfree(clk_data);
}



/* Matches for factors clocks */
static const struct of_device_id clk_factors_match[] __initconst = {
        {.compatible = "allwinner,sun4i-a10-pll1-clk", .data = &sun4i_pll1_data,},
        {.compatible = "allwinner,sun6i-a31-pll1-clk", .data = &sun6i_a31_pll1_data,},
        {.compatible = "allwinner,sun8i-a23-pll1-clk", .data = &sun8i_a23_pll1_data,},
        {.compatible = "allwinner,sun7i-a20-pll4-clk", .data = &sun7i_a20_pll4_data,},
        {.compatible = "allwinner,sun5i-a13-ahb-clk", .data = &sun5i_a13_ahb_data,},
        {.compatible = "allwinner,sun4i-a10-apb1-clk", .data = &sun4i_apb1_data,},
        {.compatible = "allwinner,sun7i-a20-out-clk", .data = &sun7i_a20_out_data,},
        {}
};

/* Matches for divider clocks */
static const struct of_device_id clk_div_match[] __initconst = {
        {.compatible = "allwinner,sun4i-a10-axi-clk", .data = &sun4i_axi_data,},
        {.compatible = "allwinner,sun8i-a23-axi-clk", .data = &sun8i_a23_axi_data,},
        {.compatible = "allwinner,sun4i-a10-ahb-clk", .data = &sun4i_ahb_data,},
        {.compatible = "allwinner,sun4i-a10-apb0-clk", .data = &sun4i_apb0_data,},
        {}
};

/* Matches for divided outputs */
static const struct of_device_id clk_divs_match[] __initconst = {
        {.compatible = "allwinner,sun4i-a10-pll5-clk", .data = &pll5_divs_data,},
        {.compatible = "allwinner,sun4i-a10-pll6-clk", .data = &pll6_divs_data,},
        {.compatible = "allwinner,sun6i-a31-pll6-clk", .data = &sun6i_a31_pll6_divs_data,},
        {}
};

/* Matches for mux clocks */
static const struct of_device_id clk_mux_match[] __initconst = {
        {.compatible = "allwinner,sun4i-a10-cpu-clk", .data = &sun4i_cpu_mux_data,},
        {.compatible = "allwinner,sun6i-a31-ahb1-mux-clk", .data = &sun6i_a31_ahb1_mux_data,},
        {}
};

/* Matches for gate clocks */
static const struct of_device_id clk_gates_match[] __initconst = {
        {.compatible = "allwinner,sun4i-a10-axi-gates-clk", .data = &sun4i_axi_gates_data,},
        {.compatible = "allwinner,sun4i-a10-ahb-gates-clk", .data = &sun4i_ahb_gates_data,},
        {.compatible = "allwinner,sun5i-a10s-ahb-gates-clk", .data = &sun5i_a10s_ahb_gates_data,},
        {.compatible = "allwinner,sun5i-a13-ahb-gates-clk", .data = &sun5i_a13_ahb_gates_data,},
        {.compatible = "allwinner,sun6i-a31-ahb1-gates-clk", .data = &sun6i_a31_ahb1_gates_data,},
        {.compatible = "allwinner,sun7i-a20-ahb-gates-clk", .data = &sun7i_a20_ahb_gates_data,},
        {.compatible = "allwinner,sun8i-a23-ahb1-gates-clk", .data = &sun8i_a23_ahb1_gates_data,},
        {.compatible = "allwinner,sun9i-a80-ahb0-gates-clk", .data = &sun9i_a80_ahb0_gates_data,},
        {.compatible = "allwinner,sun9i-a80-ahb1-gates-clk", .data = &sun9i_a80_ahb1_gates_data,},
        {.compatible = "allwinner,sun9i-a80-ahb2-gates-clk", .data = &sun9i_a80_ahb2_gates_data,},
        {.compatible = "allwinner,sun4i-a10-apb0-gates-clk", .data = &sun4i_apb0_gates_data,},
        {.compatible = "allwinner,sun5i-a10s-apb0-gates-clk", .data = &sun5i_a10s_apb0_gates_data,},
        {.compatible = "allwinner,sun5i-a13-apb0-gates-clk", .data = &sun5i_a13_apb0_gates_data,},
        {.compatible = "allwinner,sun7i-a20-apb0-gates-clk", .data = &sun7i_a20_apb0_gates_data,},
        {.compatible = "allwinner,sun9i-a80-apb0-gates-clk", .data = &sun9i_a80_apb0_gates_data,},
        {.compatible = "allwinner,sun4i-a10-apb1-gates-clk", .data = &sun4i_apb1_gates_data,},
        {.compatible = "allwinner,sun5i-a10s-apb1-gates-clk", .data = &sun5i_a10s_apb1_gates_data,},
        {.compatible = "allwinner,sun5i-a13-apb1-gates-clk", .data = &sun5i_a13_apb1_gates_data,},
        {.compatible = "allwinner,sun6i-a31-apb1-gates-clk", .data = &sun6i_a31_apb1_gates_data,},
        {.compatible = "allwinner,sun7i-a20-apb1-gates-clk", .data = &sun7i_a20_apb1_gates_data,},
        {.compatible = "allwinner,sun8i-a23-apb1-gates-clk", .data = &sun8i_a23_apb1_gates_data,},
        {.compatible = "allwinner,sun9i-a80-apb1-gates-clk", .data = &sun9i_a80_apb1_gates_data,},
        {.compatible = "allwinner,sun6i-a31-apb2-gates-clk", .data = &sun6i_a31_apb2_gates_data,},
        {.compatible = "allwinner,sun8i-a23-apb2-gates-clk", .data = &sun8i_a23_apb2_gates_data,},
        {}
};

static void __init of_sunxi_table_clock_setup(const struct of_device_id *clk_match,
                                              void *function)
{
        struct device_node *np;
        const struct div_data *data;
        const struct of_device_id *match;
        void (*setup_function)(struct device_node *, const void *) = function;

        for_each_matching_node_and_match(np, clk_match, &match) {
                data = match->data;
                setup_function(np, data);
        }
}

static void __init sunxi_init_clocks(const char *clocks[], int nclocks)
{
        unsigned int i;

        /* Register divided output clocks */
        of_sunxi_table_clock_setup(clk_divs_match, sunxi_divs_clk_setup);

        /* Register factor clocks */
        of_sunxi_table_clock_setup(clk_factors_match, sunxi_factors_clk_setup);

        /* Register divider clocks */
        of_sunxi_table_clock_setup(clk_div_match, sunxi_divider_clk_setup);

        /* Register mux clocks */
        of_sunxi_table_clock_setup(clk_mux_match, sunxi_mux_clk_setup);

        /* Register gate clocks */
        of_sunxi_table_clock_setup(clk_gates_match, sunxi_gates_clk_setup);

        /* Protect the clocks that needs to stay on */
        for (i = 0; i < nclocks; i++) {
                struct clk *clk = clk_get(NULL, clocks[i]);

                if (!IS_ERR(clk))
                        clk_prepare_enable(clk);
        }
}

static const char *sun4i_a10_critical_clocks[] __initdata = {
        "pll5_ddr",
        "ahb_sdram",
};

static void __init sun4i_a10_init_clocks(struct device_node *node)
{
        sunxi_init_clocks(sun4i_a10_critical_clocks,
                          ARRAY_SIZE(sun4i_a10_critical_clocks));
}
CLK_OF_DECLARE(sun4i_a10_clk_init, "allwinner,sun4i-a10", sun4i_a10_init_clocks);

static const char *sun5i_critical_clocks[] __initdata = {
        "cpu",
        "pll5_ddr",
        "ahb_sdram",
};

static void __init sun5i_init_clocks(struct device_node *node)
{
        sunxi_init_clocks(sun5i_critical_clocks,
                          ARRAY_SIZE(sun5i_critical_clocks));
}
CLK_OF_DECLARE(sun5i_a10s_clk_init, "allwinner,sun5i-a10s", sun5i_init_clocks);
CLK_OF_DECLARE(sun5i_a13_clk_init, "allwinner,sun5i-a13", sun5i_init_clocks);
CLK_OF_DECLARE(sun7i_a20_clk_init, "allwinner,sun7i-a20", sun5i_init_clocks);

static const char *sun6i_critical_clocks[] __initdata = {
        "cpu",
};

static void __init sun6i_init_clocks(struct device_node *node)
{
        sunxi_init_clocks(sun6i_critical_clocks,
                          ARRAY_SIZE(sun6i_critical_clocks));
}
CLK_OF_DECLARE(sun6i_a31_clk_init, "allwinner,sun6i-a31", sun6i_init_clocks);
CLK_OF_DECLARE(sun6i_a31s_clk_init, "allwinner,sun6i-a31s", sun6i_init_clocks);
CLK_OF_DECLARE(sun8i_a23_clk_init, "allwinner,sun8i-a23", sun6i_init_clocks);

static void __init sun9i_init_clocks(struct device_node *node)
{
        sunxi_init_clocks(NULL, 0);
}
CLK_OF_DECLARE(sun9i_a80_clk_init, "allwinner,sun9i-a80", sun9i_init_clocks);