drivers/clk/ti/clk-k3-pll.c - platform/external/u-boot - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Texas Instruments K3 SoC PLL clock driver
  *
  * Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com/
  *	Tero Kristo <t-kristo@ti.com>
  */

 #include <common.h>
 #include <asm/io.h>
 #include <dm.h>
 #include <div64.h>
 #include <errno.h>
 #include <clk-uclass.h>
 #include <linux/clk-provider.h>
 #include "k3-clk.h"
 #include <linux/rational.h>

 /* 16FFT register offsets */
 #define PLL_16FFT_CFG			0x08
 #define PLL_KICK0			0x10
 #define PLL_KICK1			0x14
 #define PLL_16FFT_CTRL			0x20
 #define PLL_16FFT_STAT			0x24
 #define PLL_16FFT_FREQ_CTRL0		0x30
 #define PLL_16FFT_FREQ_CTRL1		0x34
 #define PLL_16FFT_DIV_CTRL		0x38

 /* CTRL register bits */
 #define PLL_16FFT_CTRL_BYPASS_EN	BIT(31)
 #define PLL_16FFT_CTRL_PLL_EN		BIT(15)
 #define PLL_16FFT_CTRL_DSM_EN		BIT(1)

 /* STAT register bits */
 #define PLL_16FFT_STAT_LOCK		BIT(0)

 /* FREQ_CTRL0 bits */
 #define PLL_16FFT_FREQ_CTRL0_FB_DIV_INT_MASK	0xfff

 /* DIV CTRL register bits */
 #define PLL_16FFT_DIV_CTRL_REF_DIV_MASK		0x3f

 #define PLL_16FFT_FREQ_CTRL1_FB_DIV_FRAC_BITS	24
 #define PLL_16FFT_HSDIV_CTRL_CLKOUT_EN          BIT(15)

 /* KICK register magic values */
 #define PLL_KICK0_VALUE				0x68ef3490
 #define PLL_KICK1_VALUE				0xd172bc5a

 /**
  * struct ti_pll_clk - TI PLL clock data info structure
  * @clk: core clock structure
  * @reg: memory address of the PLL controller
  */
 struct ti_pll_clk {
 	struct clk	clk;
 	void __iomem	*reg;
 };

 #define to_clk_pll(_clk) container_of(_clk, struct ti_pll_clk, clk)

 static int ti_pll_wait_for_lock(struct clk *clk)
 {
 	struct ti_pll_clk *pll = to_clk_pll(clk);
 	u32 stat;
 	int i;

 	for (i = 0; i < 100000; i++) {
 		stat = readl(pll->reg + PLL_16FFT_STAT);
 		if (stat & PLL_16FFT_STAT_LOCK)
 			return 0;
 	}

 	printf("%s: pll (%s) failed to lock\n", __func__,
 	       clk->dev->name);

 	return -EBUSY;
 }

 static ulong ti_pll_clk_get_rate(struct clk *clk)
 {
 	struct ti_pll_clk *pll = to_clk_pll(clk);
 	u64 current_freq;
 	u64 parent_freq = clk_get_parent_rate(clk);
 	u32 pllm;
 	u32 plld;
 	u32 pllfm;
 	u32 ctrl;

 	/* Check if we are in bypass */
 	ctrl = readl(pll->reg + PLL_16FFT_CTRL);
 	if (ctrl & PLL_16FFT_CTRL_BYPASS_EN)
 		return parent_freq;

 	pllm = readl(pll->reg + PLL_16FFT_FREQ_CTRL0);
 	pllfm = readl(pll->reg + PLL_16FFT_FREQ_CTRL1);

 	plld = readl(pll->reg + PLL_16FFT_DIV_CTRL) &
 		PLL_16FFT_DIV_CTRL_REF_DIV_MASK;

 	current_freq = parent_freq * pllm / plld;

 	if (pllfm) {
 		u64 tmp;

 		tmp = parent_freq * pllfm;
 		do_div(tmp, plld);
 		tmp >>= PLL_16FFT_FREQ_CTRL1_FB_DIV_FRAC_BITS;
 		current_freq += tmp;
 	}

 	return current_freq;
 }

 static ulong ti_pll_clk_set_rate(struct clk *clk, ulong rate)
 {
 	struct ti_pll_clk *pll = to_clk_pll(clk);
 	u64 current_freq;
 	u64 parent_freq = clk_get_parent_rate(clk);
 	int ret;
 	u32 ctrl;
 	unsigned long pllm;
 	u32 pllfm = 0;
 	unsigned long plld;
 	u32 rem;
 	int shift;

 	debug("%s(clk=%p, rate=%u)\n", __func__, clk, (u32)rate);

 	if (ti_pll_clk_get_rate(clk) == rate)
 		return rate;

 	if (rate != parent_freq)
 		/*
 		 * Attempt with higher max multiplier value first to give
 		 * some space for fractional divider to kick in.
 		 */
 		for (shift = 8; shift >= 0; shift -= 8) {
 			rational_best_approximation(rate, parent_freq,
 				((PLL_16FFT_FREQ_CTRL0_FB_DIV_INT_MASK + 1) << shift) - 1,
 				PLL_16FFT_DIV_CTRL_REF_DIV_MASK, &pllm, &plld);
 			if (pllm / plld <= PLL_16FFT_FREQ_CTRL0_FB_DIV_INT_MASK)
 				break;
 		}

 	/* Put PLL to bypass mode */
 	ctrl = readl(pll->reg + PLL_16FFT_CTRL);
 	ctrl |= PLL_16FFT_CTRL_BYPASS_EN;
 	writel(ctrl, pll->reg + PLL_16FFT_CTRL);

 	if (rate == parent_freq) {
 		debug("%s: put %s to bypass\n", __func__, clk->dev->name);
 		return rate;
 	}

 	debug("%s: pre-frac-calc: rate=%u, parent_freq=%u, plld=%u, pllm=%u\n",
 	      __func__, (u32)rate, (u32)parent_freq, (u32)plld, (u32)pllm);

 	/* Check if we need fractional config */
 	if (plld > 1) {
 		pllfm = pllm % plld;
 		pllfm <<= PLL_16FFT_FREQ_CTRL1_FB_DIV_FRAC_BITS;
 		rem = pllfm % plld;
 		pllfm /= plld;
 		if (rem)
 			pllfm++;
 		pllm /= plld;
 		plld = 1;
 	}

 	if (pllfm)
 		ctrl |= PLL_16FFT_CTRL_DSM_EN;
 	else
 		ctrl &= ~PLL_16FFT_CTRL_DSM_EN;

 	writel(pllm, pll->reg + PLL_16FFT_FREQ_CTRL0);
 	writel(pllfm, pll->reg + PLL_16FFT_FREQ_CTRL1);
 	writel(plld, pll->reg + PLL_16FFT_DIV_CTRL);

 	ctrl &= ~PLL_16FFT_CTRL_BYPASS_EN;
 	ctrl |= PLL_16FFT_CTRL_PLL_EN;
 	writel(ctrl, pll->reg + PLL_16FFT_CTRL);

 	ret = ti_pll_wait_for_lock(clk);
 	if (ret)
 		return ret;

 	debug("%s: pllm=%u, plld=%u, pllfm=%u, parent_freq=%u\n",
 	      __func__, (u32)pllm, (u32)plld, (u32)pllfm, (u32)parent_freq);

 	current_freq = parent_freq * pllm / plld;

 	if (pllfm) {
 		u64 tmp;

 		tmp = parent_freq * pllfm;
 		do_div(tmp, plld);
 		tmp >>= PLL_16FFT_FREQ_CTRL1_FB_DIV_FRAC_BITS;
 		current_freq += tmp;
 	}

 	return current_freq;
 }

 static int ti_pll_clk_enable(struct clk *clk)
 {
 	struct ti_pll_clk *pll = to_clk_pll(clk);
 	u32 ctrl;

 	ctrl = readl(pll->reg + PLL_16FFT_CTRL);
 	ctrl &= ~PLL_16FFT_CTRL_BYPASS_EN;
 	ctrl |= PLL_16FFT_CTRL_PLL_EN;
 	writel(ctrl, pll->reg + PLL_16FFT_CTRL);

 	return ti_pll_wait_for_lock(clk);
 }

 static int ti_pll_clk_disable(struct clk *clk)
 {
 	struct ti_pll_clk *pll = to_clk_pll(clk);
 	u32 ctrl;

 	ctrl = readl(pll->reg + PLL_16FFT_CTRL);
 	ctrl |= PLL_16FFT_CTRL_BYPASS_EN;
 	writel(ctrl, pll->reg + PLL_16FFT_CTRL);

 	return 0;
 }

 static const struct clk_ops ti_pll_clk_ops = {
 	.get_rate = ti_pll_clk_get_rate,
 	.set_rate = ti_pll_clk_set_rate,
 	.enable = ti_pll_clk_enable,
 	.disable = ti_pll_clk_disable,
 };

 struct clk *clk_register_ti_pll(const char *name, const char *parent_name,
 				void __iomem *reg)
 {
 	struct ti_pll_clk *pll;
 	int ret;
 	int i;
 	u32 cfg, ctrl, hsdiv_presence_bit, hsdiv_ctrl_offs;

 	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
 	if (!pll)
 		return ERR_PTR(-ENOMEM);

 	pll->reg = reg;

 	ret = clk_register(&pll->clk, "ti-pll-clk", name, parent_name);
 	if (ret) {
 		printf("%s: failed to register: %d\n", __func__, ret);
 		kfree(pll);
 		return ERR_PTR(ret);
 	}

 	/* Unlock the PLL registers */
 	writel(PLL_KICK0_VALUE, pll->reg + PLL_KICK0);
 	writel(PLL_KICK1_VALUE, pll->reg + PLL_KICK1);

 	/* Enable all HSDIV outputs */
 	cfg = readl(pll->reg + PLL_16FFT_CFG);
 	for (i = 0; i < 16; i++) {
 		hsdiv_presence_bit = BIT(16 + i);
 		hsdiv_ctrl_offs = 0x80 + (i * 4);
 		/* Enable HSDIV output if present */
 		if ((hsdiv_presence_bit & cfg) != 0UL) {
 			ctrl = readl(pll->reg + hsdiv_ctrl_offs);
 			ctrl |= PLL_16FFT_HSDIV_CTRL_CLKOUT_EN;
 			writel(ctrl, pll->reg + hsdiv_ctrl_offs);
 		}
 	}

 	return &pll->clk;
 }

 U_BOOT_DRIVER(ti_pll_clk) = {
 	.name = "ti-pll-clk",
 	.id = UCLASS_CLK,
 	.ops = &ti_pll_clk_ops,
 	.flags = DM_FLAG_PRE_RELOC,
 };
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Texas Instruments K3 SoC PLL clock driver
	*
	* Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com/
	* Tero Kristo <t-kristo@ti.com>
	*/

	#include <common.h>
	#include <asm/io.h>
	#include <dm.h>
	#include <div64.h>
	#include <errno.h>
	#include <clk-uclass.h>
	#include <linux/clk-provider.h>
	#include "k3-clk.h"
	#include <linux/rational.h>

	/* 16FFT register offsets */
	#define PLL_16FFT_CFG 0x08
	#define PLL_KICK0 0x10
	#define PLL_KICK1 0x14
	#define PLL_16FFT_CTRL 0x20
	#define PLL_16FFT_STAT 0x24
	#define PLL_16FFT_FREQ_CTRL0 0x30
	#define PLL_16FFT_FREQ_CTRL1 0x34
	#define PLL_16FFT_DIV_CTRL 0x38

	/* CTRL register bits */
	#define PLL_16FFT_CTRL_BYPASS_EN BIT(31)
	#define PLL_16FFT_CTRL_PLL_EN BIT(15)
	#define PLL_16FFT_CTRL_DSM_EN BIT(1)

	/* STAT register bits */
	#define PLL_16FFT_STAT_LOCK BIT(0)

	/* FREQ_CTRL0 bits */
	#define PLL_16FFT_FREQ_CTRL0_FB_DIV_INT_MASK 0xfff

	/* DIV CTRL register bits */
	#define PLL_16FFT_DIV_CTRL_REF_DIV_MASK 0x3f

	#define PLL_16FFT_FREQ_CTRL1_FB_DIV_FRAC_BITS 24
	#define PLL_16FFT_HSDIV_CTRL_CLKOUT_EN BIT(15)

	/* KICK register magic values */
	#define PLL_KICK0_VALUE 0x68ef3490
	#define PLL_KICK1_VALUE 0xd172bc5a

	/**
	* struct ti_pll_clk - TI PLL clock data info structure
	* @clk: core clock structure
	* @reg: memory address of the PLL controller
	*/
	struct ti_pll_clk {
	struct clk clk;
	void __iomem *reg;
	};

	#define to_clk_pll(_clk) container_of(_clk, struct ti_pll_clk, clk)

	static int ti_pll_wait_for_lock(struct clk *clk)
	{
	struct ti_pll_clk *pll = to_clk_pll(clk);
	u32 stat;
	int i;

	for (i = 0; i < 100000; i++) {
	stat = readl(pll->reg + PLL_16FFT_STAT);
	if (stat & PLL_16FFT_STAT_LOCK)
	return 0;
	}

	printf("%s: pll (%s) failed to lock\n", __func__,
	clk->dev->name);

	return -EBUSY;
	}

	static ulong ti_pll_clk_get_rate(struct clk *clk)
	{
	struct ti_pll_clk *pll = to_clk_pll(clk);
	u64 current_freq;
	u64 parent_freq = clk_get_parent_rate(clk);
	u32 pllm;
	u32 plld;
	u32 pllfm;
	u32 ctrl;

	/* Check if we are in bypass */
	ctrl = readl(pll->reg + PLL_16FFT_CTRL);
	if (ctrl & PLL_16FFT_CTRL_BYPASS_EN)
	return parent_freq;

	pllm = readl(pll->reg + PLL_16FFT_FREQ_CTRL0);
	pllfm = readl(pll->reg + PLL_16FFT_FREQ_CTRL1);

	plld = readl(pll->reg + PLL_16FFT_DIV_CTRL) &
	PLL_16FFT_DIV_CTRL_REF_DIV_MASK;

	current_freq = parent_freq * pllm / plld;

	if (pllfm) {
	u64 tmp;

	tmp = parent_freq * pllfm;
	do_div(tmp, plld);
	tmp >>= PLL_16FFT_FREQ_CTRL1_FB_DIV_FRAC_BITS;
	current_freq += tmp;
	}

	return current_freq;
	}

	static ulong ti_pll_clk_set_rate(struct clk *clk, ulong rate)
	{
	struct ti_pll_clk *pll = to_clk_pll(clk);
	u64 current_freq;
	u64 parent_freq = clk_get_parent_rate(clk);
	int ret;
	u32 ctrl;
	unsigned long pllm;
	u32 pllfm = 0;
	unsigned long plld;
	u32 rem;
	int shift;

	debug("%s(clk=%p, rate=%u)\n", __func__, clk, (u32)rate);

	if (ti_pll_clk_get_rate(clk) == rate)
	return rate;

	if (rate != parent_freq)
	/*
	* Attempt with higher max multiplier value first to give
	* some space for fractional divider to kick in.
	*/
	for (shift = 8; shift >= 0; shift -= 8) {
	rational_best_approximation(rate, parent_freq,
	((PLL_16FFT_FREQ_CTRL0_FB_DIV_INT_MASK + 1) << shift) - 1,
	PLL_16FFT_DIV_CTRL_REF_DIV_MASK, &pllm, &plld);
	if (pllm / plld <= PLL_16FFT_FREQ_CTRL0_FB_DIV_INT_MASK)
	break;
	}

	/* Put PLL to bypass mode */
	ctrl = readl(pll->reg + PLL_16FFT_CTRL);
	ctrl \|= PLL_16FFT_CTRL_BYPASS_EN;
	writel(ctrl, pll->reg + PLL_16FFT_CTRL);

	if (rate == parent_freq) {
	debug("%s: put %s to bypass\n", __func__, clk->dev->name);
	return rate;
	}

	debug("%s: pre-frac-calc: rate=%u, parent_freq=%u, plld=%u, pllm=%u\n",
	__func__, (u32)rate, (u32)parent_freq, (u32)plld, (u32)pllm);

	/* Check if we need fractional config */
	if (plld > 1) {
	pllfm = pllm % plld;
	pllfm <<= PLL_16FFT_FREQ_CTRL1_FB_DIV_FRAC_BITS;
	rem = pllfm % plld;
	pllfm /= plld;
	if (rem)
	pllfm++;
	pllm /= plld;
	plld = 1;
	}

	if (pllfm)
	ctrl \|= PLL_16FFT_CTRL_DSM_EN;
	else
	ctrl &= ~PLL_16FFT_CTRL_DSM_EN;

	writel(pllm, pll->reg + PLL_16FFT_FREQ_CTRL0);
	writel(pllfm, pll->reg + PLL_16FFT_FREQ_CTRL1);
	writel(plld, pll->reg + PLL_16FFT_DIV_CTRL);

	ctrl &= ~PLL_16FFT_CTRL_BYPASS_EN;
	ctrl \|= PLL_16FFT_CTRL_PLL_EN;
	writel(ctrl, pll->reg + PLL_16FFT_CTRL);

	ret = ti_pll_wait_for_lock(clk);
	if (ret)
	return ret;

	debug("%s: pllm=%u, plld=%u, pllfm=%u, parent_freq=%u\n",
	__func__, (u32)pllm, (u32)plld, (u32)pllfm, (u32)parent_freq);

	current_freq = parent_freq * pllm / plld;

	if (pllfm) {
	u64 tmp;

	tmp = parent_freq * pllfm;
	do_div(tmp, plld);
	tmp >>= PLL_16FFT_FREQ_CTRL1_FB_DIV_FRAC_BITS;
	current_freq += tmp;
	}

	return current_freq;
	}

	static int ti_pll_clk_enable(struct clk *clk)
	{
	struct ti_pll_clk *pll = to_clk_pll(clk);
	u32 ctrl;

	ctrl = readl(pll->reg + PLL_16FFT_CTRL);
	ctrl &= ~PLL_16FFT_CTRL_BYPASS_EN;
	ctrl \|= PLL_16FFT_CTRL_PLL_EN;
	writel(ctrl, pll->reg + PLL_16FFT_CTRL);

	return ti_pll_wait_for_lock(clk);
	}

	static int ti_pll_clk_disable(struct clk *clk)
	{
	struct ti_pll_clk *pll = to_clk_pll(clk);
	u32 ctrl;

	ctrl = readl(pll->reg + PLL_16FFT_CTRL);
	ctrl \|= PLL_16FFT_CTRL_BYPASS_EN;
	writel(ctrl, pll->reg + PLL_16FFT_CTRL);

	return 0;
	}

	static const struct clk_ops ti_pll_clk_ops = {
	.get_rate = ti_pll_clk_get_rate,
	.set_rate = ti_pll_clk_set_rate,
	.enable = ti_pll_clk_enable,
	.disable = ti_pll_clk_disable,
	};

	struct clk clk_register_ti_pll(const char name, const char *parent_name,
	void __iomem *reg)
	{
	struct ti_pll_clk *pll;
	int ret;
	int i;
	u32 cfg, ctrl, hsdiv_presence_bit, hsdiv_ctrl_offs;

	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
	if (!pll)
	return ERR_PTR(-ENOMEM);

	pll->reg = reg;

	ret = clk_register(&pll->clk, "ti-pll-clk", name, parent_name);
	if (ret) {
	printf("%s: failed to register: %d\n", __func__, ret);
	kfree(pll);
	return ERR_PTR(ret);
	}

	/* Unlock the PLL registers */
	writel(PLL_KICK0_VALUE, pll->reg + PLL_KICK0);
	writel(PLL_KICK1_VALUE, pll->reg + PLL_KICK1);

	/* Enable all HSDIV outputs */
	cfg = readl(pll->reg + PLL_16FFT_CFG);
	for (i = 0; i < 16; i++) {
	hsdiv_presence_bit = BIT(16 + i);
	hsdiv_ctrl_offs = 0x80 + (i * 4);
	/* Enable HSDIV output if present */
	if ((hsdiv_presence_bit & cfg) != 0UL) {
	ctrl = readl(pll->reg + hsdiv_ctrl_offs);
	ctrl \|= PLL_16FFT_HSDIV_CTRL_CLKOUT_EN;
	writel(ctrl, pll->reg + hsdiv_ctrl_offs);
	}
	}

	return &pll->clk;
	}

	U_BOOT_DRIVER(ti_pll_clk) = {
	.name = "ti-pll-clk",
	.id = UCLASS_CLK,
	.ops = &ti_pll_clk_ops,
	.flags = DM_FLAG_PRE_RELOC,
	};