drivers/clk/mvebu/ap-cpu-clk.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Marvell Armada AP CPU Clock Controller
  *
  * Copyright (C) 2018 Marvell
  *
  * Omri Itach <omrii@marvell.com>
  * Gregory Clement <gregory.clement@bootlin.com>
  */

 #define pr_fmt(fmt) "ap-cpu-clk: " fmt

 #include <linux/clk-provider.h>
 #include <linux/clk.h>
 #include <linux/mfd/syscon.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
 #include "armada_ap_cp_helper.h"

 #define AP806_CPU_CLUSTER0		0
 #define AP806_CPU_CLUSTER1		1
 #define AP806_CPUS_PER_CLUSTER		2
 #define APN806_CPU1_MASK		0x1

 #define APN806_CLUSTER_NUM_OFFSET	8
 #define APN806_CLUSTER_NUM_MASK		BIT(APN806_CLUSTER_NUM_OFFSET)

 #define APN806_MAX_DIVIDER		32

 /**
  * struct cpu_dfs_regs: CPU DFS register mapping
  * @divider_reg: full integer ratio from PLL frequency to CPU clock frequency
  * @force_reg: request to force new ratio regardless of relation to other clocks
  * @ratio_reg: central request to switch ratios
  */
 struct cpu_dfs_regs {
 	unsigned int divider_reg;
 	unsigned int force_reg;
 	unsigned int ratio_reg;
 	unsigned int ratio_state_reg;
 	unsigned int divider_mask;
 	unsigned int cluster_offset;
 	unsigned int force_mask;
 	int divider_offset;
 	int divider_ratio;
 	int ratio_offset;
 	int ratio_state_offset;
 	int ratio_state_cluster_offset;
 };

 /* AP806 CPU DFS register mapping*/
 #define AP806_CA72MP2_0_PLL_CR_0_REG_OFFSET		0x278
 #define AP806_CA72MP2_0_PLL_CR_1_REG_OFFSET		0x280
 #define AP806_CA72MP2_0_PLL_CR_2_REG_OFFSET		0x284
 #define AP806_CA72MP2_0_PLL_SR_REG_OFFSET		0xC94

 #define AP806_CA72MP2_0_PLL_CR_CLUSTER_OFFSET		0x14
 #define AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET		0
 #define AP806_PLL_CR_CPU_CLK_DIV_RATIO			0
 #define AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_MASK \
 			(0x3f << AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET)
 #define AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_OFFSET	24
 #define AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_MASK \
 			(0x1 << AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_OFFSET)
 #define AP806_PLL_CR_0_CPU_CLK_RELOAD_RATIO_OFFSET	16
 #define AP806_CA72MP2_0_PLL_RATIO_STABLE_OFFSET	0
 #define AP806_CA72MP2_0_PLL_RATIO_STATE			11

 #define STATUS_POLL_PERIOD_US		1
 #define STATUS_POLL_TIMEOUT_US		1000000

 #define to_ap_cpu_clk(_hw) container_of(_hw, struct ap_cpu_clk, hw)

 static const struct cpu_dfs_regs ap806_dfs_regs = {
 	.divider_reg = AP806_CA72MP2_0_PLL_CR_0_REG_OFFSET,
 	.force_reg = AP806_CA72MP2_0_PLL_CR_1_REG_OFFSET,
 	.ratio_reg = AP806_CA72MP2_0_PLL_CR_2_REG_OFFSET,
 	.ratio_state_reg = AP806_CA72MP2_0_PLL_SR_REG_OFFSET,
 	.divider_mask = AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_MASK,
 	.cluster_offset = AP806_CA72MP2_0_PLL_CR_CLUSTER_OFFSET,
 	.force_mask = AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_MASK,
 	.divider_offset = AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET,
 	.divider_ratio = AP806_PLL_CR_CPU_CLK_DIV_RATIO,
 	.ratio_offset = AP806_PLL_CR_0_CPU_CLK_RELOAD_RATIO_OFFSET,
 	.ratio_state_offset = AP806_CA72MP2_0_PLL_RATIO_STABLE_OFFSET,
 	.ratio_state_cluster_offset = AP806_CA72MP2_0_PLL_RATIO_STABLE_OFFSET,
 };

 /* AP807 CPU DFS register mapping */
 #define AP807_DEVICE_GENERAL_CONTROL_10_REG_OFFSET		0x278
 #define AP807_DEVICE_GENERAL_CONTROL_11_REG_OFFSET		0x27c
 #define AP807_DEVICE_GENERAL_STATUS_6_REG_OFFSET		0xc98
 #define AP807_CA72MP2_0_PLL_CR_CLUSTER_OFFSET			0x8
 #define AP807_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET			18
 #define AP807_PLL_CR_0_CPU_CLK_DIV_RATIO_MASK \
 		(0x3f << AP807_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET)
 #define AP807_PLL_CR_1_CPU_CLK_DIV_RATIO_OFFSET			12
 #define AP807_PLL_CR_1_CPU_CLK_DIV_RATIO_MASK \
 		(0x3f << AP807_PLL_CR_1_CPU_CLK_DIV_RATIO_OFFSET)
 #define AP807_PLL_CR_CPU_CLK_DIV_RATIO				3
 #define AP807_PLL_CR_0_CPU_CLK_RELOAD_FORCE_OFFSET		0
 #define AP807_PLL_CR_0_CPU_CLK_RELOAD_FORCE_MASK \
 		(0x3 << AP807_PLL_CR_0_CPU_CLK_RELOAD_FORCE_OFFSET)
 #define AP807_PLL_CR_0_CPU_CLK_RELOAD_RATIO_OFFSET		6
 #define	AP807_CA72MP2_0_PLL_CLKDIV_RATIO_STABLE_OFFSET		20
 #define AP807_CA72MP2_0_PLL_CLKDIV_RATIO_STABLE_CLUSTER_OFFSET	3

 static const struct cpu_dfs_regs ap807_dfs_regs = {
 	.divider_reg = AP807_DEVICE_GENERAL_CONTROL_10_REG_OFFSET,
 	.force_reg = AP807_DEVICE_GENERAL_CONTROL_11_REG_OFFSET,
 	.ratio_reg = AP807_DEVICE_GENERAL_CONTROL_11_REG_OFFSET,
 	.ratio_state_reg = AP807_DEVICE_GENERAL_STATUS_6_REG_OFFSET,
 	.divider_mask = AP807_PLL_CR_0_CPU_CLK_DIV_RATIO_MASK,
 	.cluster_offset = AP807_CA72MP2_0_PLL_CR_CLUSTER_OFFSET,
 	.force_mask = AP807_PLL_CR_0_CPU_CLK_RELOAD_FORCE_MASK,
 	.divider_offset = AP807_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET,
 	.divider_ratio = AP807_PLL_CR_CPU_CLK_DIV_RATIO,
 	.ratio_offset = AP807_PLL_CR_0_CPU_CLK_RELOAD_RATIO_OFFSET,
 	.ratio_state_offset = AP807_CA72MP2_0_PLL_CLKDIV_RATIO_STABLE_OFFSET,
 	.ratio_state_cluster_offset =
 		AP807_CA72MP2_0_PLL_CLKDIV_RATIO_STABLE_CLUSTER_OFFSET
 };

 /*
  * struct ap806_clk: CPU cluster clock controller instance
  * @cluster: Cluster clock controller index
  * @clk_name: Cluster clock controller name
  * @dev : Cluster clock device
  * @hw: HW specific structure of Cluster clock controller
  * @pll_cr_base: CA72MP2 Register base (Device Sample at Reset register)
  */
 struct ap_cpu_clk {
 	unsigned int cluster;
 	const char *clk_name;
 	struct device *dev;
 	struct clk_hw hw;
 	struct regmap *pll_cr_base;
 	const struct cpu_dfs_regs *pll_regs;
 };

 static unsigned long ap_cpu_clk_recalc_rate(struct clk_hw *hw,
 					    unsigned long parent_rate)
 {
 	struct ap_cpu_clk *clk = to_ap_cpu_clk(hw);
 	unsigned int cpu_clkdiv_reg;
 	int cpu_clkdiv_ratio;

 	cpu_clkdiv_reg = clk->pll_regs->divider_reg +
 		(clk->cluster * clk->pll_regs->cluster_offset);
 	regmap_read(clk->pll_cr_base, cpu_clkdiv_reg, &cpu_clkdiv_ratio);
 	cpu_clkdiv_ratio &= clk->pll_regs->divider_mask;
 	cpu_clkdiv_ratio >>= clk->pll_regs->divider_offset;

 	return parent_rate / cpu_clkdiv_ratio;
 }

 static int ap_cpu_clk_set_rate(struct clk_hw *hw, unsigned long rate,
 			       unsigned long parent_rate)
 {
 	struct ap_cpu_clk *clk = to_ap_cpu_clk(hw);
 	int ret, reg, divider = parent_rate / rate;
 	unsigned int cpu_clkdiv_reg, cpu_force_reg, cpu_ratio_reg, stable_bit;

 	cpu_clkdiv_reg = clk->pll_regs->divider_reg +
 		(clk->cluster * clk->pll_regs->cluster_offset);
 	cpu_force_reg = clk->pll_regs->force_reg +
 		(clk->cluster * clk->pll_regs->cluster_offset);
 	cpu_ratio_reg = clk->pll_regs->ratio_reg +
 		(clk->cluster * clk->pll_regs->cluster_offset);

 	regmap_read(clk->pll_cr_base, cpu_clkdiv_reg, &reg);
 	reg &= ~(clk->pll_regs->divider_mask);
 	reg |= (divider << clk->pll_regs->divider_offset);

 	/*
 	 * AP807 CPU divider has two channels with ratio 1:3 and divider_ratio
 	 * is 1. Otherwise, in the case of the AP806, divider_ratio is 0.
 	 */
 	if (clk->pll_regs->divider_ratio) {
 		reg &= ~(AP807_PLL_CR_1_CPU_CLK_DIV_RATIO_MASK);
 		reg |= ((divider * clk->pll_regs->divider_ratio) <<
 				AP807_PLL_CR_1_CPU_CLK_DIV_RATIO_OFFSET);
 	}
 	regmap_write(clk->pll_cr_base, cpu_clkdiv_reg, reg);


 	regmap_update_bits(clk->pll_cr_base, cpu_force_reg,
 			   clk->pll_regs->force_mask,
 			   clk->pll_regs->force_mask);

 	regmap_update_bits(clk->pll_cr_base, cpu_ratio_reg,
 			   BIT(clk->pll_regs->ratio_offset),
 			   BIT(clk->pll_regs->ratio_offset));

 	stable_bit = BIT(clk->pll_regs->ratio_state_offset +
 			 clk->cluster *
 			 clk->pll_regs->ratio_state_cluster_offset);
 	ret = regmap_read_poll_timeout(clk->pll_cr_base,
 				       clk->pll_regs->ratio_state_reg, reg,
 				       reg & stable_bit, STATUS_POLL_PERIOD_US,
 				       STATUS_POLL_TIMEOUT_US);
 	if (ret)
 		return ret;

 	regmap_update_bits(clk->pll_cr_base, cpu_ratio_reg,
 			   BIT(clk->pll_regs->ratio_offset), 0);

 	return 0;
 }

 static long ap_cpu_clk_round_rate(struct clk_hw *hw, unsigned long rate,
 				  unsigned long *parent_rate)
 {
 	int divider = *parent_rate / rate;

 	divider = min(divider, APN806_MAX_DIVIDER);

 	return *parent_rate / divider;
 }

 static const struct clk_ops ap_cpu_clk_ops = {
 	.recalc_rate	= ap_cpu_clk_recalc_rate,
 	.round_rate	= ap_cpu_clk_round_rate,
 	.set_rate	= ap_cpu_clk_set_rate,
 };

 static int ap_cpu_clock_probe(struct platform_device *pdev)
 {
 	int ret, nclusters = 0, cluster_index = 0;
 	struct device *dev = &pdev->dev;
 	struct device_node *dn, *np = dev->of_node;
 	struct clk_hw_onecell_data *ap_cpu_data;
 	struct ap_cpu_clk *ap_cpu_clk;
 	struct regmap *regmap;

 	regmap = syscon_node_to_regmap(np->parent);
 	if (IS_ERR(regmap)) {
 		pr_err("cannot get pll_cr_base regmap\n");
 		return PTR_ERR(regmap);
 	}

 	/*
 	 * AP806 has 4 cpus and DFS for AP806 is controlled per
 	 * cluster (2 CPUs per cluster), cpu0 and cpu1 are fixed to
 	 * cluster0 while cpu2 and cpu3 are fixed to cluster1 whether
 	 * they are enabled or not.  Since cpu0 is the boot cpu, then
 	 * cluster0 must exist.  If cpu2 or cpu3 is enabled, cluster1
 	 * will exist and the cluster number is 2; otherwise the
 	 * cluster number is 1.
 	 */
 	nclusters = 1;
 	for_each_of_cpu_node(dn) {
 		int cpu, err;

 		err = of_property_read_u32(dn, "reg", &cpu);
 		if (WARN_ON(err))
 			return err;

 		/* If cpu2 or cpu3 is enabled */
 		if (cpu & APN806_CLUSTER_NUM_MASK) {
 			nclusters = 2;
 			break;
 		}
 	}
 	/*
 	 * DFS for AP806 is controlled per cluster (2 CPUs per cluster),
 	 * so allocate structs per cluster
 	 */
 	ap_cpu_clk = devm_kcalloc(dev, nclusters, sizeof(*ap_cpu_clk),
 				  GFP_KERNEL);
 	if (!ap_cpu_clk)
 		return -ENOMEM;

 	ap_cpu_data = devm_kzalloc(dev, struct_size(ap_cpu_data, hws,
 						    nclusters),
 				GFP_KERNEL);
 	if (!ap_cpu_data)
 		return -ENOMEM;

 	for_each_of_cpu_node(dn) {
 		char *clk_name = "cpu-cluster-0";
 		struct clk_init_data init;
 		const char *parent_name;
 		struct clk *parent;
 		int cpu, err;

 		err = of_property_read_u32(dn, "reg", &cpu);
 		if (WARN_ON(err))
 			return err;

 		cluster_index = cpu & APN806_CLUSTER_NUM_MASK;
 		cluster_index >>= APN806_CLUSTER_NUM_OFFSET;

 		/* Initialize once for one cluster */
 		if (ap_cpu_data->hws[cluster_index])
 			continue;

 		parent = of_clk_get(np, cluster_index);
 		if (IS_ERR(parent)) {
 			dev_err(dev, "Could not get the clock parent\n");
 			return -EINVAL;
 		}
 		parent_name =  __clk_get_name(parent);
 		clk_name[12] += cluster_index;
 		ap_cpu_clk[cluster_index].clk_name =
 			ap_cp_unique_name(dev, np->parent, clk_name);
 		ap_cpu_clk[cluster_index].cluster = cluster_index;
 		ap_cpu_clk[cluster_index].pll_cr_base = regmap;
 		ap_cpu_clk[cluster_index].hw.init = &init;
 		ap_cpu_clk[cluster_index].dev = dev;
 		ap_cpu_clk[cluster_index].pll_regs = of_device_get_match_data(&pdev->dev);

 		init.name = ap_cpu_clk[cluster_index].clk_name;
 		init.ops = &ap_cpu_clk_ops;
 		init.num_parents = 1;
 		init.parent_names = &parent_name;

 		ret = devm_clk_hw_register(dev, &ap_cpu_clk[cluster_index].hw);
 		if (ret)
 			return ret;
 		ap_cpu_data->hws[cluster_index] = &ap_cpu_clk[cluster_index].hw;
 	}

 	ap_cpu_data->num = cluster_index + 1;

 	ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, ap_cpu_data);
 	if (ret)
 		dev_err(dev, "failed to register OF clock provider\n");

 	return ret;
 }

 static const struct of_device_id ap_cpu_clock_of_match[] = {
 	{
 		.compatible = "marvell,ap806-cpu-clock",
 		.data = &ap806_dfs_regs,
 	},
 	{
 		.compatible = "marvell,ap807-cpu-clock",
 		.data = &ap807_dfs_regs,
 	},
 	{ }
 };

 static struct platform_driver ap_cpu_clock_driver = {
 	.probe = ap_cpu_clock_probe,
 	.driver		= {
 		.name	= "marvell-ap-cpu-clock",
 		.of_match_table = ap_cpu_clock_of_match,
 		.suppress_bind_attrs = true,
 	},
 };
 builtin_platform_driver(ap_cpu_clock_driver);
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Marvell Armada AP CPU Clock Controller
	*
	* Copyright (C) 2018 Marvell
	*
	* Omri Itach <omrii@marvell.com>
	* Gregory Clement <gregory.clement@bootlin.com>
	*/

	#define pr_fmt(fmt) "ap-cpu-clk: " fmt

	#include <linux/clk-provider.h>
	#include <linux/clk.h>
	#include <linux/mfd/syscon.h>
	#include <linux/of.h>
	#include <linux/of_address.h>
	#include <linux/of_platform.h>
	#include <linux/platform_device.h>
	#include <linux/regmap.h>
	#include "armada_ap_cp_helper.h"

	#define AP806_CPU_CLUSTER0 0
	#define AP806_CPU_CLUSTER1 1
	#define AP806_CPUS_PER_CLUSTER 2
	#define APN806_CPU1_MASK 0x1

	#define APN806_CLUSTER_NUM_OFFSET 8
	#define APN806_CLUSTER_NUM_MASK BIT(APN806_CLUSTER_NUM_OFFSET)

	#define APN806_MAX_DIVIDER 32

	/**
	* struct cpu_dfs_regs: CPU DFS register mapping
	* @divider_reg: full integer ratio from PLL frequency to CPU clock frequency
	* @force_reg: request to force new ratio regardless of relation to other clocks
	* @ratio_reg: central request to switch ratios
	*/
	struct cpu_dfs_regs {
	unsigned int divider_reg;
	unsigned int force_reg;
	unsigned int ratio_reg;
	unsigned int ratio_state_reg;
	unsigned int divider_mask;
	unsigned int cluster_offset;
	unsigned int force_mask;
	int divider_offset;
	int divider_ratio;
	int ratio_offset;
	int ratio_state_offset;
	int ratio_state_cluster_offset;
	};

	/* AP806 CPU DFS register mapping*/
	#define AP806_CA72MP2_0_PLL_CR_0_REG_OFFSET 0x278
	#define AP806_CA72MP2_0_PLL_CR_1_REG_OFFSET 0x280
	#define AP806_CA72MP2_0_PLL_CR_2_REG_OFFSET 0x284
	#define AP806_CA72MP2_0_PLL_SR_REG_OFFSET 0xC94

	#define AP806_CA72MP2_0_PLL_CR_CLUSTER_OFFSET 0x14
	#define AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET 0
	#define AP806_PLL_CR_CPU_CLK_DIV_RATIO 0
	#define AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_MASK \
	(0x3f << AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET)
	#define AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_OFFSET 24
	#define AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_MASK \
	(0x1 << AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_OFFSET)
	#define AP806_PLL_CR_0_CPU_CLK_RELOAD_RATIO_OFFSET 16
	#define AP806_CA72MP2_0_PLL_RATIO_STABLE_OFFSET 0
	#define AP806_CA72MP2_0_PLL_RATIO_STATE 11

	#define STATUS_POLL_PERIOD_US 1
	#define STATUS_POLL_TIMEOUT_US 1000000

	#define to_ap_cpu_clk(_hw) container_of(_hw, struct ap_cpu_clk, hw)

	static const struct cpu_dfs_regs ap806_dfs_regs = {
	.divider_reg = AP806_CA72MP2_0_PLL_CR_0_REG_OFFSET,
	.force_reg = AP806_CA72MP2_0_PLL_CR_1_REG_OFFSET,
	.ratio_reg = AP806_CA72MP2_0_PLL_CR_2_REG_OFFSET,
	.ratio_state_reg = AP806_CA72MP2_0_PLL_SR_REG_OFFSET,
	.divider_mask = AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_MASK,
	.cluster_offset = AP806_CA72MP2_0_PLL_CR_CLUSTER_OFFSET,
	.force_mask = AP806_PLL_CR_0_CPU_CLK_RELOAD_FORCE_MASK,
	.divider_offset = AP806_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET,
	.divider_ratio = AP806_PLL_CR_CPU_CLK_DIV_RATIO,
	.ratio_offset = AP806_PLL_CR_0_CPU_CLK_RELOAD_RATIO_OFFSET,
	.ratio_state_offset = AP806_CA72MP2_0_PLL_RATIO_STABLE_OFFSET,
	.ratio_state_cluster_offset = AP806_CA72MP2_0_PLL_RATIO_STABLE_OFFSET,
	};

	/* AP807 CPU DFS register mapping */
	#define AP807_DEVICE_GENERAL_CONTROL_10_REG_OFFSET 0x278
	#define AP807_DEVICE_GENERAL_CONTROL_11_REG_OFFSET 0x27c
	#define AP807_DEVICE_GENERAL_STATUS_6_REG_OFFSET 0xc98
	#define AP807_CA72MP2_0_PLL_CR_CLUSTER_OFFSET 0x8
	#define AP807_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET 18
	#define AP807_PLL_CR_0_CPU_CLK_DIV_RATIO_MASK \
	(0x3f << AP807_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET)
	#define AP807_PLL_CR_1_CPU_CLK_DIV_RATIO_OFFSET 12
	#define AP807_PLL_CR_1_CPU_CLK_DIV_RATIO_MASK \
	(0x3f << AP807_PLL_CR_1_CPU_CLK_DIV_RATIO_OFFSET)
	#define AP807_PLL_CR_CPU_CLK_DIV_RATIO 3
	#define AP807_PLL_CR_0_CPU_CLK_RELOAD_FORCE_OFFSET 0
	#define AP807_PLL_CR_0_CPU_CLK_RELOAD_FORCE_MASK \
	(0x3 << AP807_PLL_CR_0_CPU_CLK_RELOAD_FORCE_OFFSET)
	#define AP807_PLL_CR_0_CPU_CLK_RELOAD_RATIO_OFFSET 6
	#define AP807_CA72MP2_0_PLL_CLKDIV_RATIO_STABLE_OFFSET 20
	#define AP807_CA72MP2_0_PLL_CLKDIV_RATIO_STABLE_CLUSTER_OFFSET 3

	static const struct cpu_dfs_regs ap807_dfs_regs = {
	.divider_reg = AP807_DEVICE_GENERAL_CONTROL_10_REG_OFFSET,
	.force_reg = AP807_DEVICE_GENERAL_CONTROL_11_REG_OFFSET,
	.ratio_reg = AP807_DEVICE_GENERAL_CONTROL_11_REG_OFFSET,
	.ratio_state_reg = AP807_DEVICE_GENERAL_STATUS_6_REG_OFFSET,
	.divider_mask = AP807_PLL_CR_0_CPU_CLK_DIV_RATIO_MASK,
	.cluster_offset = AP807_CA72MP2_0_PLL_CR_CLUSTER_OFFSET,
	.force_mask = AP807_PLL_CR_0_CPU_CLK_RELOAD_FORCE_MASK,
	.divider_offset = AP807_PLL_CR_0_CPU_CLK_DIV_RATIO_OFFSET,
	.divider_ratio = AP807_PLL_CR_CPU_CLK_DIV_RATIO,
	.ratio_offset = AP807_PLL_CR_0_CPU_CLK_RELOAD_RATIO_OFFSET,
	.ratio_state_offset = AP807_CA72MP2_0_PLL_CLKDIV_RATIO_STABLE_OFFSET,
	.ratio_state_cluster_offset =
	AP807_CA72MP2_0_PLL_CLKDIV_RATIO_STABLE_CLUSTER_OFFSET
	};

	/*
	* struct ap806_clk: CPU cluster clock controller instance
	* @cluster: Cluster clock controller index
	* @clk_name: Cluster clock controller name
	* @dev : Cluster clock device
	* @hw: HW specific structure of Cluster clock controller
	* @pll_cr_base: CA72MP2 Register base (Device Sample at Reset register)
	*/
	struct ap_cpu_clk {
	unsigned int cluster;
	const char *clk_name;
	struct device *dev;
	struct clk_hw hw;
	struct regmap *pll_cr_base;
	const struct cpu_dfs_regs *pll_regs;
	};

	static unsigned long ap_cpu_clk_recalc_rate(struct clk_hw *hw,
	unsigned long parent_rate)
	{
	struct ap_cpu_clk *clk = to_ap_cpu_clk(hw);
	unsigned int cpu_clkdiv_reg;
	int cpu_clkdiv_ratio;

	cpu_clkdiv_reg = clk->pll_regs->divider_reg +
	(clk->cluster * clk->pll_regs->cluster_offset);
	regmap_read(clk->pll_cr_base, cpu_clkdiv_reg, &cpu_clkdiv_ratio);
	cpu_clkdiv_ratio &= clk->pll_regs->divider_mask;
	cpu_clkdiv_ratio >>= clk->pll_regs->divider_offset;

	return parent_rate / cpu_clkdiv_ratio;
	}

	static int ap_cpu_clk_set_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long parent_rate)
	{
	struct ap_cpu_clk *clk = to_ap_cpu_clk(hw);
	int ret, reg, divider = parent_rate / rate;
	unsigned int cpu_clkdiv_reg, cpu_force_reg, cpu_ratio_reg, stable_bit;

	cpu_clkdiv_reg = clk->pll_regs->divider_reg +
	(clk->cluster * clk->pll_regs->cluster_offset);
	cpu_force_reg = clk->pll_regs->force_reg +
	(clk->cluster * clk->pll_regs->cluster_offset);
	cpu_ratio_reg = clk->pll_regs->ratio_reg +
	(clk->cluster * clk->pll_regs->cluster_offset);

	regmap_read(clk->pll_cr_base, cpu_clkdiv_reg, &reg);
	reg &= ~(clk->pll_regs->divider_mask);
	reg \|= (divider << clk->pll_regs->divider_offset);

	/*
	* AP807 CPU divider has two channels with ratio 1:3 and divider_ratio
	* is 1. Otherwise, in the case of the AP806, divider_ratio is 0.
	*/
	if (clk->pll_regs->divider_ratio) {
	reg &= ~(AP807_PLL_CR_1_CPU_CLK_DIV_RATIO_MASK);
	reg \|= ((divider * clk->pll_regs->divider_ratio) <<
	AP807_PLL_CR_1_CPU_CLK_DIV_RATIO_OFFSET);
	}
	regmap_write(clk->pll_cr_base, cpu_clkdiv_reg, reg);


	regmap_update_bits(clk->pll_cr_base, cpu_force_reg,
	clk->pll_regs->force_mask,
	clk->pll_regs->force_mask);

	regmap_update_bits(clk->pll_cr_base, cpu_ratio_reg,
	BIT(clk->pll_regs->ratio_offset),
	BIT(clk->pll_regs->ratio_offset));

	stable_bit = BIT(clk->pll_regs->ratio_state_offset +
	clk->cluster *
	clk->pll_regs->ratio_state_cluster_offset);
	ret = regmap_read_poll_timeout(clk->pll_cr_base,
	clk->pll_regs->ratio_state_reg, reg,
	reg & stable_bit, STATUS_POLL_PERIOD_US,
	STATUS_POLL_TIMEOUT_US);
	if (ret)
	return ret;

	regmap_update_bits(clk->pll_cr_base, cpu_ratio_reg,
	BIT(clk->pll_regs->ratio_offset), 0);

	return 0;
	}

	static long ap_cpu_clk_round_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long *parent_rate)
	{
	int divider = *parent_rate / rate;

	divider = min(divider, APN806_MAX_DIVIDER);

	return *parent_rate / divider;
	}

	static const struct clk_ops ap_cpu_clk_ops = {
	.recalc_rate = ap_cpu_clk_recalc_rate,
	.round_rate = ap_cpu_clk_round_rate,
	.set_rate = ap_cpu_clk_set_rate,
	};

	static int ap_cpu_clock_probe(struct platform_device *pdev)
	{
	int ret, nclusters = 0, cluster_index = 0;
	struct device *dev = &pdev->dev;
	struct device_node dn, np = dev->of_node;
	struct clk_hw_onecell_data *ap_cpu_data;
	struct ap_cpu_clk *ap_cpu_clk;
	struct regmap *regmap;

	regmap = syscon_node_to_regmap(np->parent);
	if (IS_ERR(regmap)) {
	pr_err("cannot get pll_cr_base regmap\n");
	return PTR_ERR(regmap);
	}

	/*
	* AP806 has 4 cpus and DFS for AP806 is controlled per
	* cluster (2 CPUs per cluster), cpu0 and cpu1 are fixed to
	* cluster0 while cpu2 and cpu3 are fixed to cluster1 whether
	* they are enabled or not. Since cpu0 is the boot cpu, then
	* cluster0 must exist. If cpu2 or cpu3 is enabled, cluster1
	* will exist and the cluster number is 2; otherwise the
	* cluster number is 1.
	*/
	nclusters = 1;
	for_each_of_cpu_node(dn) {
	int cpu, err;

	err = of_property_read_u32(dn, "reg", &cpu);
	if (WARN_ON(err))
	return err;

	/* If cpu2 or cpu3 is enabled */
	if (cpu & APN806_CLUSTER_NUM_MASK) {
	nclusters = 2;
	break;
	}
	}
	/*
	* DFS for AP806 is controlled per cluster (2 CPUs per cluster),
	* so allocate structs per cluster
	*/
	ap_cpu_clk = devm_kcalloc(dev, nclusters, sizeof(*ap_cpu_clk),
	GFP_KERNEL);
	if (!ap_cpu_clk)
	return -ENOMEM;

	ap_cpu_data = devm_kzalloc(dev, struct_size(ap_cpu_data, hws,
	nclusters),
	GFP_KERNEL);
	if (!ap_cpu_data)
	return -ENOMEM;

	for_each_of_cpu_node(dn) {
	char *clk_name = "cpu-cluster-0";
	struct clk_init_data init;
	const char *parent_name;
	struct clk *parent;
	int cpu, err;

	err = of_property_read_u32(dn, "reg", &cpu);
	if (WARN_ON(err))
	return err;

	cluster_index = cpu & APN806_CLUSTER_NUM_MASK;
	cluster_index >>= APN806_CLUSTER_NUM_OFFSET;

	/* Initialize once for one cluster */
	if (ap_cpu_data->hws[cluster_index])
	continue;

	parent = of_clk_get(np, cluster_index);
	if (IS_ERR(parent)) {
	dev_err(dev, "Could not get the clock parent\n");
	return -EINVAL;
	}
	parent_name = __clk_get_name(parent);
	clk_name[12] += cluster_index;
	ap_cpu_clk[cluster_index].clk_name =
	ap_cp_unique_name(dev, np->parent, clk_name);
	ap_cpu_clk[cluster_index].cluster = cluster_index;
	ap_cpu_clk[cluster_index].pll_cr_base = regmap;
	ap_cpu_clk[cluster_index].hw.init = &init;
	ap_cpu_clk[cluster_index].dev = dev;
	ap_cpu_clk[cluster_index].pll_regs = of_device_get_match_data(&pdev->dev);

	init.name = ap_cpu_clk[cluster_index].clk_name;
	init.ops = &ap_cpu_clk_ops;
	init.num_parents = 1;
	init.parent_names = &parent_name;

	ret = devm_clk_hw_register(dev, &ap_cpu_clk[cluster_index].hw);
	if (ret)
	return ret;
	ap_cpu_data->hws[cluster_index] = &ap_cpu_clk[cluster_index].hw;
	}

	ap_cpu_data->num = cluster_index + 1;

	ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, ap_cpu_data);
	if (ret)
	dev_err(dev, "failed to register OF clock provider\n");

	return ret;
	}

	static const struct of_device_id ap_cpu_clock_of_match[] = {
	{
	.compatible = "marvell,ap806-cpu-clock",
	.data = &ap806_dfs_regs,
	},
	{
	.compatible = "marvell,ap807-cpu-clock",
	.data = &ap807_dfs_regs,
	},
	{ }
	};

	static struct platform_driver ap_cpu_clock_driver = {
	.probe = ap_cpu_clock_probe,
	.driver = {
	.name = "marvell-ap-cpu-clock",
	.of_match_table = ap_cpu_clock_of_match,
	.suppress_bind_attrs = true,
	},
	};
	builtin_platform_driver(ap_cpu_clock_driver);