root/drivers/clk/mmp/clk-audio.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * MMP Audio Clock Controller driver
 *
 * Copyright (C) 2020 Lubomir Rintel <lkundrak@v3.sk>
 */

#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm_clock.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <dt-bindings/clock/marvell,mmp2-audio.h>

/* Audio Controller Registers */
#define SSPA_AUD_CTRL                           0x04
#define SSPA_AUD_PLL_CTRL0                      0x08
#define SSPA_AUD_PLL_CTRL1                      0x0c

/* SSPA Audio Control Register */
#define SSPA_AUD_CTRL_SYSCLK_SHIFT              0
#define SSPA_AUD_CTRL_SYSCLK_DIV_SHIFT          1
#define SSPA_AUD_CTRL_SSPA0_MUX_SHIFT           7
#define SSPA_AUD_CTRL_SSPA0_SHIFT               8
#define SSPA_AUD_CTRL_SSPA0_DIV_SHIFT           9
#define SSPA_AUD_CTRL_SSPA1_SHIFT               16
#define SSPA_AUD_CTRL_SSPA1_DIV_SHIFT           17
#define SSPA_AUD_CTRL_SSPA1_MUX_SHIFT           23
#define SSPA_AUD_CTRL_DIV_MASK                  0x7e

/* SSPA Audio PLL Control 0 Register */
#define SSPA_AUD_PLL_CTRL0_DIV_OCLK_MODULO_MASK (0x7 << 28)
#define SSPA_AUD_PLL_CTRL0_DIV_OCLK_MODULO(x)   ((x) << 28)
#define SSPA_AUD_PLL_CTRL0_FRACT_MASK           (0xfffff << 8)
#define SSPA_AUD_PLL_CTRL0_FRACT(x)             ((x) << 8)
#define SSPA_AUD_PLL_CTRL0_ENA_DITHER           (1 << 7)
#define SSPA_AUD_PLL_CTRL0_ICP_2UA              (0 << 5)
#define SSPA_AUD_PLL_CTRL0_ICP_5UA              (1 << 5)
#define SSPA_AUD_PLL_CTRL0_ICP_7UA              (2 << 5)
#define SSPA_AUD_PLL_CTRL0_ICP_10UA             (3 << 5)
#define SSPA_AUD_PLL_CTRL0_DIV_FBCCLK_MASK      (0x3 << 3)
#define SSPA_AUD_PLL_CTRL0_DIV_FBCCLK(x)        ((x) << 3)
#define SSPA_AUD_PLL_CTRL0_DIV_MCLK_MASK        (0x1 << 2)
#define SSPA_AUD_PLL_CTRL0_DIV_MCLK(x)          ((x) << 2)
#define SSPA_AUD_PLL_CTRL0_PD_OVPROT_DIS        (1 << 1)
#define SSPA_AUD_PLL_CTRL0_PU                   (1 << 0)

/* SSPA Audio PLL Control 1 Register */
#define SSPA_AUD_PLL_CTRL1_SEL_FAST_CLK         (1 << 24)
#define SSPA_AUD_PLL_CTRL1_CLK_SEL_MASK         (1 << 11)
#define SSPA_AUD_PLL_CTRL1_CLK_SEL_AUDIO_PLL    (1 << 11)
#define SSPA_AUD_PLL_CTRL1_CLK_SEL_VCXO         (0 << 11)
#define SSPA_AUD_PLL_CTRL1_DIV_OCLK_PATTERN_MASK (0x7ff << 0)
#define SSPA_AUD_PLL_CTRL1_DIV_OCLK_PATTERN(x)  ((x) << 0)

#define CLK_AUDIO_NR_CLKS                       3

struct mmp2_audio_clk {
        void __iomem *mmio_base;

        struct clk_hw audio_pll_hw;
        struct clk_mux sspa_mux;
        struct clk_mux sspa1_mux;
        struct clk_divider sysclk_div;
        struct clk_divider sspa0_div;
        struct clk_divider sspa1_div;
        struct clk_gate sysclk_gate;
        struct clk_gate sspa0_gate;
        struct clk_gate sspa1_gate;

        u32 aud_ctrl;
        u32 aud_pll_ctrl0;
        u32 aud_pll_ctrl1;

        spinlock_t lock;

        /* Must be last */
        struct clk_hw_onecell_data clk_data;
};

static const struct {
        unsigned long parent_rate;
        unsigned long freq_vco;
        unsigned char mclk;
        unsigned char fbcclk;
        unsigned short fract;
} predivs[] = {
        { 26000000, 135475200, 0, 0, 0x8a18 },
        { 26000000, 147456000, 0, 1, 0x0da1 },
        { 38400000, 135475200, 1, 2, 0x8208 },
        { 38400000, 147456000, 1, 3, 0xaaaa },
};

static const struct {
        unsigned char divisor;
        unsigned char modulo;
        unsigned char pattern;
} postdivs[] = {
        {   1,  3,  0, },
        {   2,  5,  0, },
        {   4,  0,  0, },
        {   6,  1,  1, },
        {   8,  1,  0, },
        {   9,  1,  2, },
        {  12,  2,  1, },
        {  16,  2,  0, },
        {  18,  2,  2, },
        {  24,  4,  1, },
        {  36,  4,  2, },
        {  48,  6,  1, },
        {  72,  6,  2, },
};

static unsigned long audio_pll_recalc_rate(struct clk_hw *hw,
                                           unsigned long parent_rate)
{
        struct mmp2_audio_clk *priv = container_of(hw, struct mmp2_audio_clk, audio_pll_hw);
        unsigned int prediv;
        unsigned int postdiv;
        u32 aud_pll_ctrl0;
        u32 aud_pll_ctrl1;

        aud_pll_ctrl0 = readl(priv->mmio_base + SSPA_AUD_PLL_CTRL0);
        aud_pll_ctrl0 &= SSPA_AUD_PLL_CTRL0_DIV_OCLK_MODULO_MASK |
                         SSPA_AUD_PLL_CTRL0_FRACT_MASK |
                         SSPA_AUD_PLL_CTRL0_ENA_DITHER |
                         SSPA_AUD_PLL_CTRL0_DIV_FBCCLK_MASK |
                         SSPA_AUD_PLL_CTRL0_DIV_MCLK_MASK |
                         SSPA_AUD_PLL_CTRL0_PU;

        aud_pll_ctrl1 = readl(priv->mmio_base + SSPA_AUD_PLL_CTRL1);
        aud_pll_ctrl1 &= SSPA_AUD_PLL_CTRL1_CLK_SEL_MASK |
                         SSPA_AUD_PLL_CTRL1_DIV_OCLK_PATTERN_MASK;

        for (prediv = 0; prediv < ARRAY_SIZE(predivs); prediv++) {
                if (predivs[prediv].parent_rate != parent_rate)
                        continue;
                for (postdiv = 0; postdiv < ARRAY_SIZE(postdivs); postdiv++) {
                        unsigned long freq;
                        u32 val;

                        val = SSPA_AUD_PLL_CTRL0_ENA_DITHER;
                        val |= SSPA_AUD_PLL_CTRL0_PU;
                        val |= SSPA_AUD_PLL_CTRL0_DIV_OCLK_MODULO(postdivs[postdiv].modulo);
                        val |= SSPA_AUD_PLL_CTRL0_FRACT(predivs[prediv].fract);
                        val |= SSPA_AUD_PLL_CTRL0_DIV_FBCCLK(predivs[prediv].fbcclk);
                        val |= SSPA_AUD_PLL_CTRL0_DIV_MCLK(predivs[prediv].mclk);
                        if (val != aud_pll_ctrl0)
                                continue;

                        val = SSPA_AUD_PLL_CTRL1_CLK_SEL_AUDIO_PLL;
                        val |= SSPA_AUD_PLL_CTRL1_DIV_OCLK_PATTERN(postdivs[postdiv].pattern);
                        if (val != aud_pll_ctrl1)
                                continue;

                        freq = predivs[prediv].freq_vco;
                        freq /= postdivs[postdiv].divisor;
                        return freq;
                }
        }

        return 0;
}

static int audio_pll_determine_rate(struct clk_hw *hw,
                                    struct clk_rate_request *req)
{
        unsigned int prediv;
        unsigned int postdiv;
        long rounded = 0;

        for (prediv = 0; prediv < ARRAY_SIZE(predivs); prediv++) {
                if (predivs[prediv].parent_rate != req->best_parent_rate)
                        continue;
                for (postdiv = 0; postdiv < ARRAY_SIZE(postdivs); postdiv++) {
                        long freq = predivs[prediv].freq_vco;

                        freq /= postdivs[postdiv].divisor;
                        if (freq == req->rate)
                                return 0;
                        if (freq < req->rate)
                                continue;
                        if (rounded && freq > rounded)
                                continue;
                        rounded = freq;
                }
        }

        req->rate = rounded;

        return 0;
}

static int audio_pll_set_rate(struct clk_hw *hw, unsigned long rate,
                              unsigned long parent_rate)
{
        struct mmp2_audio_clk *priv = container_of(hw, struct mmp2_audio_clk, audio_pll_hw);
        unsigned int prediv;
        unsigned int postdiv;
        unsigned long val;

        for (prediv = 0; prediv < ARRAY_SIZE(predivs); prediv++) {
                if (predivs[prediv].parent_rate != parent_rate)
                        continue;

                for (postdiv = 0; postdiv < ARRAY_SIZE(postdivs); postdiv++) {
                        if (rate * postdivs[postdiv].divisor != predivs[prediv].freq_vco)
                                continue;

                        val = SSPA_AUD_PLL_CTRL0_ENA_DITHER;
                        val |= SSPA_AUD_PLL_CTRL0_PU;
                        val |= SSPA_AUD_PLL_CTRL0_DIV_OCLK_MODULO(postdivs[postdiv].modulo);
                        val |= SSPA_AUD_PLL_CTRL0_FRACT(predivs[prediv].fract);
                        val |= SSPA_AUD_PLL_CTRL0_DIV_FBCCLK(predivs[prediv].fbcclk);
                        val |= SSPA_AUD_PLL_CTRL0_DIV_MCLK(predivs[prediv].mclk);
                        writel(val, priv->mmio_base + SSPA_AUD_PLL_CTRL0);

                        val = SSPA_AUD_PLL_CTRL1_CLK_SEL_AUDIO_PLL;
                        val |= SSPA_AUD_PLL_CTRL1_DIV_OCLK_PATTERN(postdivs[postdiv].pattern);
                        writel(val, priv->mmio_base + SSPA_AUD_PLL_CTRL1);

                        return 0;
                }
        }

        return -ERANGE;
}

static const struct clk_ops audio_pll_ops = {
        .recalc_rate = audio_pll_recalc_rate,
        .determine_rate = audio_pll_determine_rate,
        .set_rate = audio_pll_set_rate,
};

static int register_clocks(struct mmp2_audio_clk *priv, struct device *dev)
{
        const struct clk_parent_data sspa_mux_parents[] = {
                { .hw = &priv->audio_pll_hw },
                { .fw_name = "i2s0" },
        };
        const struct clk_parent_data sspa1_mux_parents[] = {
                { .hw = &priv->audio_pll_hw },
                { .fw_name = "i2s1" },
        };
        int ret;

        priv->audio_pll_hw.init = CLK_HW_INIT_FW_NAME("audio_pll",
                                "vctcxo", &audio_pll_ops,
                                CLK_SET_RATE_PARENT);
        ret = devm_clk_hw_register(dev, &priv->audio_pll_hw);
        if (ret)
                return ret;

        priv->sspa_mux.hw.init = CLK_HW_INIT_PARENTS_DATA("sspa_mux",
                                sspa_mux_parents, &clk_mux_ops,
                                CLK_SET_RATE_PARENT);
        priv->sspa_mux.reg = priv->mmio_base + SSPA_AUD_CTRL;
        priv->sspa_mux.mask = 1;
        priv->sspa_mux.shift = SSPA_AUD_CTRL_SSPA0_MUX_SHIFT;
        ret = devm_clk_hw_register(dev, &priv->sspa_mux.hw);
        if (ret)
                return ret;

        priv->sysclk_div.hw.init = CLK_HW_INIT_HW("sys_div",
                                &priv->sspa_mux.hw, &clk_divider_ops,
                                CLK_SET_RATE_PARENT);
        priv->sysclk_div.reg = priv->mmio_base + SSPA_AUD_CTRL;
        priv->sysclk_div.shift = SSPA_AUD_CTRL_SYSCLK_DIV_SHIFT;
        priv->sysclk_div.width = 6;
        priv->sysclk_div.flags = CLK_DIVIDER_ONE_BASED;
        priv->sysclk_div.flags |= CLK_DIVIDER_ROUND_CLOSEST;
        priv->sysclk_div.flags |= CLK_DIVIDER_ALLOW_ZERO;
        ret = devm_clk_hw_register(dev, &priv->sysclk_div.hw);
        if (ret)
                return ret;

        priv->sysclk_gate.hw.init = CLK_HW_INIT_HW("sys_clk",
                                &priv->sysclk_div.hw, &clk_gate_ops,
                                CLK_SET_RATE_PARENT);
        priv->sysclk_gate.reg = priv->mmio_base + SSPA_AUD_CTRL;
        priv->sysclk_gate.bit_idx = SSPA_AUD_CTRL_SYSCLK_SHIFT;
        ret = devm_clk_hw_register(dev, &priv->sysclk_gate.hw);
        if (ret)
                return ret;

        priv->sspa0_div.hw.init = CLK_HW_INIT_HW("sspa0_div",
                                &priv->sspa_mux.hw, &clk_divider_ops, 0);
        priv->sspa0_div.reg = priv->mmio_base + SSPA_AUD_CTRL;
        priv->sspa0_div.shift = SSPA_AUD_CTRL_SSPA0_DIV_SHIFT;
        priv->sspa0_div.width = 6;
        priv->sspa0_div.flags = CLK_DIVIDER_ONE_BASED;
        priv->sspa0_div.flags |= CLK_DIVIDER_ROUND_CLOSEST;
        priv->sspa0_div.flags |= CLK_DIVIDER_ALLOW_ZERO;
        ret = devm_clk_hw_register(dev, &priv->sspa0_div.hw);
        if (ret)
                return ret;

        priv->sspa0_gate.hw.init = CLK_HW_INIT_HW("sspa0_clk",
                                &priv->sspa0_div.hw, &clk_gate_ops,
                                CLK_SET_RATE_PARENT);
        priv->sspa0_gate.reg = priv->mmio_base + SSPA_AUD_CTRL;
        priv->sspa0_gate.bit_idx = SSPA_AUD_CTRL_SSPA0_SHIFT;
        ret = devm_clk_hw_register(dev, &priv->sspa0_gate.hw);
        if (ret)
                return ret;

        priv->sspa1_mux.hw.init = CLK_HW_INIT_PARENTS_DATA("sspa1_mux",
                                sspa1_mux_parents, &clk_mux_ops,
                                CLK_SET_RATE_PARENT);
        priv->sspa1_mux.reg = priv->mmio_base + SSPA_AUD_CTRL;
        priv->sspa1_mux.mask = 1;
        priv->sspa1_mux.shift = SSPA_AUD_CTRL_SSPA1_MUX_SHIFT;
        ret = devm_clk_hw_register(dev, &priv->sspa1_mux.hw);
        if (ret)
                return ret;

        priv->sspa1_div.hw.init = CLK_HW_INIT_HW("sspa1_div",
                                &priv->sspa1_mux.hw, &clk_divider_ops, 0);
        priv->sspa1_div.reg = priv->mmio_base + SSPA_AUD_CTRL;
        priv->sspa1_div.shift = SSPA_AUD_CTRL_SSPA1_DIV_SHIFT;
        priv->sspa1_div.width = 6;
        priv->sspa1_div.flags = CLK_DIVIDER_ONE_BASED;
        priv->sspa1_div.flags |= CLK_DIVIDER_ROUND_CLOSEST;
        priv->sspa1_div.flags |= CLK_DIVIDER_ALLOW_ZERO;
        ret = devm_clk_hw_register(dev, &priv->sspa1_div.hw);
        if (ret)
                return ret;

        priv->sspa1_gate.hw.init = CLK_HW_INIT_HW("sspa1_clk",
                                &priv->sspa1_div.hw, &clk_gate_ops,
                                CLK_SET_RATE_PARENT);
        priv->sspa1_gate.reg = priv->mmio_base + SSPA_AUD_CTRL;
        priv->sspa1_gate.bit_idx = SSPA_AUD_CTRL_SSPA1_SHIFT;
        ret = devm_clk_hw_register(dev, &priv->sspa1_gate.hw);
        if (ret)
                return ret;

        priv->clk_data.hws[MMP2_CLK_AUDIO_SYSCLK] = &priv->sysclk_gate.hw;
        priv->clk_data.hws[MMP2_CLK_AUDIO_SSPA0] = &priv->sspa0_gate.hw;
        priv->clk_data.hws[MMP2_CLK_AUDIO_SSPA1] = &priv->sspa1_gate.hw;
        priv->clk_data.num = CLK_AUDIO_NR_CLKS;

        return of_clk_add_hw_provider(dev->of_node, of_clk_hw_onecell_get,
                                      &priv->clk_data);
}

static int mmp2_audio_clk_probe(struct platform_device *pdev)
{
        struct mmp2_audio_clk *priv;
        int ret;

        priv = devm_kzalloc(&pdev->dev,
                            struct_size(priv, clk_data.hws,
                                        CLK_AUDIO_NR_CLKS),
                            GFP_KERNEL);
        if (!priv)
                return -ENOMEM;

        spin_lock_init(&priv->lock);
        platform_set_drvdata(pdev, priv);

        priv->mmio_base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(priv->mmio_base))
                return PTR_ERR(priv->mmio_base);

        pm_runtime_enable(&pdev->dev);
        ret = pm_clk_create(&pdev->dev);
        if (ret)
                goto disable_pm_runtime;

        ret = pm_clk_add(&pdev->dev, "audio");
        if (ret)
                goto destroy_pm_clk;

        ret = register_clocks(priv, &pdev->dev);
        if (ret)
                goto destroy_pm_clk;

        return 0;

destroy_pm_clk:
        pm_clk_destroy(&pdev->dev);
disable_pm_runtime:
        pm_runtime_disable(&pdev->dev);

        return ret;
}

static void mmp2_audio_clk_remove(struct platform_device *pdev)
{
        pm_clk_destroy(&pdev->dev);
        pm_runtime_disable(&pdev->dev);
}

#ifdef CONFIG_PM
static int mmp2_audio_clk_suspend(struct device *dev)
{
        struct mmp2_audio_clk *priv = dev_get_drvdata(dev);

        priv->aud_ctrl = readl(priv->mmio_base + SSPA_AUD_CTRL);
        priv->aud_pll_ctrl0 = readl(priv->mmio_base + SSPA_AUD_PLL_CTRL0);
        priv->aud_pll_ctrl1 = readl(priv->mmio_base + SSPA_AUD_PLL_CTRL1);
        pm_clk_suspend(dev);

        return 0;
}

static int mmp2_audio_clk_resume(struct device *dev)
{
        struct mmp2_audio_clk *priv = dev_get_drvdata(dev);

        pm_clk_resume(dev);
        writel(priv->aud_ctrl, priv->mmio_base + SSPA_AUD_CTRL);
        writel(priv->aud_pll_ctrl0, priv->mmio_base + SSPA_AUD_PLL_CTRL0);
        writel(priv->aud_pll_ctrl1, priv->mmio_base + SSPA_AUD_PLL_CTRL1);

        return 0;
}
#endif

static const struct dev_pm_ops mmp2_audio_clk_pm_ops = {
        SET_RUNTIME_PM_OPS(mmp2_audio_clk_suspend, mmp2_audio_clk_resume, NULL)
};

static const struct of_device_id mmp2_audio_clk_of_match[] = {
        { .compatible = "marvell,mmp2-audio-clock" },
        {}
};

MODULE_DEVICE_TABLE(of, mmp2_audio_clk_of_match);

static struct platform_driver mmp2_audio_clk_driver = {
        .driver = {
                .name = "mmp2-audio-clock",
                .of_match_table = of_match_ptr(mmp2_audio_clk_of_match),
                .pm = &mmp2_audio_clk_pm_ops,
        },
        .probe = mmp2_audio_clk_probe,
        .remove = mmp2_audio_clk_remove,
};
module_platform_driver(mmp2_audio_clk_driver);

MODULE_AUTHOR("Lubomir Rintel <lkundrak@v3.sk>");
MODULE_DESCRIPTION("Clock driver for MMP2 Audio subsystem");
MODULE_LICENSE("GPL");