xref: /openbmc/linux/drivers/clk/mmp/clk-audio.c (revision 46c13513)

// 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 long audio_pll_round_rate(struct clk_hw *hw, unsigned long rate,
				 unsigned long *parent_rate)
{
	unsigned int prediv;
	unsigned int postdiv;
	long rounded = 0;

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

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

	return rounded;
}

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,
	.round_rate = audio_pll_round_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_new = 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");