drivers/clk/renesas/rcar-gen4-cpg.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * R-Car Gen4 Clock Pulse Generator
  *
  * Copyright (C) 2021 Renesas Electronics Corp.
  *
  * Based on rcar-gen3-cpg.c
  *
  * Copyright (C) 2015-2018 Glider bvba
  * Copyright (C) 2019 Renesas Electronics Corp.
  */

 #include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/slab.h>

 #include "renesas-cpg-mssr.h"
 #include "rcar-gen4-cpg.h"
 #include "rcar-cpg-lib.h"

 static const struct rcar_gen4_cpg_pll_config *cpg_pll_config __initconst;
 static unsigned int cpg_clk_extalr __initdata;
 static u32 cpg_mode __initdata;

 /*
  * Z0 Clock & Z1 Clock
  */
 #define CPG_FRQCRB			0x00000804
 #define CPG_FRQCRB_KICK			BIT(31)
 #define CPG_FRQCRC			0x00000808

 struct cpg_z_clk {
 	struct clk_hw hw;
 	void __iomem *reg;
 	void __iomem *kick_reg;
 	unsigned long max_rate;		/* Maximum rate for normal mode */
 	unsigned int fixed_div;
 	u32 mask;
 };

 #define to_z_clk(_hw)	container_of(_hw, struct cpg_z_clk, hw)

 static unsigned long cpg_z_clk_recalc_rate(struct clk_hw *hw,
 					   unsigned long parent_rate)
 {
 	struct cpg_z_clk *zclk = to_z_clk(hw);
 	unsigned int mult;
 	u32 val;

 	val = readl(zclk->reg) & zclk->mask;
 	mult = 32 - (val >> __ffs(zclk->mask));

 	return DIV_ROUND_CLOSEST_ULL((u64)parent_rate * mult,
 				     32 * zclk->fixed_div);
 }

 static int cpg_z_clk_determine_rate(struct clk_hw *hw,
 				    struct clk_rate_request *req)
 {
 	struct cpg_z_clk *zclk = to_z_clk(hw);
 	unsigned int min_mult, max_mult, mult;
 	unsigned long rate, prate;

 	rate = min(req->rate, req->max_rate);
 	if (rate <= zclk->max_rate) {
 		/* Set parent rate to initial value for normal modes */
 		prate = zclk->max_rate;
 	} else {
 		/* Set increased parent rate for boost modes */
 		prate = rate;
 	}
 	req->best_parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw),
 						  prate * zclk->fixed_div);

 	prate = req->best_parent_rate / zclk->fixed_div;
 	min_mult = max(div64_ul(req->min_rate * 32ULL, prate), 1ULL);
 	max_mult = min(div64_ul(req->max_rate * 32ULL, prate), 32ULL);
 	if (max_mult < min_mult)
 		return -EINVAL;

 	mult = DIV_ROUND_CLOSEST_ULL(rate * 32ULL, prate);
 	mult = clamp(mult, min_mult, max_mult);

 	req->rate = DIV_ROUND_CLOSEST_ULL((u64)prate * mult, 32);
 	return 0;
 }

 static int cpg_z_clk_set_rate(struct clk_hw *hw, unsigned long rate,
 			      unsigned long parent_rate)
 {
 	struct cpg_z_clk *zclk = to_z_clk(hw);
 	unsigned int mult;
 	unsigned int i;

 	mult = DIV64_U64_ROUND_CLOSEST(rate * 32ULL * zclk->fixed_div,
 				       parent_rate);
 	mult = clamp(mult, 1U, 32U);

 	if (readl(zclk->kick_reg) & CPG_FRQCRB_KICK)
 		return -EBUSY;

 	cpg_reg_modify(zclk->reg, zclk->mask, (32 - mult) << __ffs(zclk->mask));

 	/*
 	 * Set KICK bit in FRQCRB to update hardware setting and wait for
 	 * clock change completion.
 	 */
 	cpg_reg_modify(zclk->kick_reg, 0, CPG_FRQCRB_KICK);

 	/*
 	 * Note: There is no HW information about the worst case latency.
 	 *
 	 * Using experimental measurements, it seems that no more than
 	 * ~10 iterations are needed, independently of the CPU rate.
 	 * Since this value might be dependent on external xtal rate, pll1
 	 * rate or even the other emulation clocks rate, use 1000 as a
 	 * "super" safe value.
 	 */
 	for (i = 1000; i; i--) {
 		if (!(readl(zclk->kick_reg) & CPG_FRQCRB_KICK))
 			return 0;

 		cpu_relax();
 	}

 	return -ETIMEDOUT;
 }

 static const struct clk_ops cpg_z_clk_ops = {
 	.recalc_rate = cpg_z_clk_recalc_rate,
 	.determine_rate = cpg_z_clk_determine_rate,
 	.set_rate = cpg_z_clk_set_rate,
 };

 static struct clk * __init cpg_z_clk_register(const char *name,
 					      const char *parent_name,
 					      void __iomem *reg,
 					      unsigned int div,
 					      unsigned int offset)
 {
 	struct clk_init_data init = {};
 	struct cpg_z_clk *zclk;
 	struct clk *clk;

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

 	init.name = name;
 	init.ops = &cpg_z_clk_ops;
 	init.flags = CLK_SET_RATE_PARENT;
 	init.parent_names = &parent_name;
 	init.num_parents = 1;

 	zclk->reg = reg + CPG_FRQCRC;
 	zclk->kick_reg = reg + CPG_FRQCRB;
 	zclk->hw.init = &init;
 	zclk->mask = GENMASK(offset + 4, offset);
 	zclk->fixed_div = div; /* PLLVCO x 1/div x SYS-CPU divider */

 	clk = clk_register(NULL, &zclk->hw);
 	if (IS_ERR(clk)) {
 		kfree(zclk);
 		return clk;
 	}

 	zclk->max_rate = clk_hw_get_rate(clk_hw_get_parent(&zclk->hw)) /
 			 zclk->fixed_div;
 	return clk;
 }

 /*
  * RPC Clocks
  */
 static const struct clk_div_table cpg_rpcsrc_div_table[] = {
 	{ 0, 4 }, { 1, 6 }, { 2, 5 }, { 3, 6 }, { 0, 0 },
 };

 struct clk * __init rcar_gen4_cpg_clk_register(struct device *dev,
 	const struct cpg_core_clk *core, const struct cpg_mssr_info *info,
 	struct clk **clks, void __iomem *base,
 	struct raw_notifier_head *notifiers)
 {
 	const struct clk *parent;
 	unsigned int mult = 1;
 	unsigned int div = 1;
 	u32 value;

 	parent = clks[core->parent & 0xffff];	/* some types use high bits */
 	if (IS_ERR(parent))
 		return ERR_CAST(parent);

 	switch (core->type) {
 	case CLK_TYPE_GEN4_MAIN:
 		div = cpg_pll_config->extal_div;
 		break;

 	case CLK_TYPE_GEN4_PLL1:
 		mult = cpg_pll_config->pll1_mult;
 		div = cpg_pll_config->pll1_div;
 		break;

 	case CLK_TYPE_GEN4_PLL2:
 		mult = cpg_pll_config->pll2_mult;
 		div = cpg_pll_config->pll2_div;
 		break;

 	case CLK_TYPE_GEN4_PLL3:
 		mult = cpg_pll_config->pll3_mult;
 		div = cpg_pll_config->pll3_div;
 		break;

 	case CLK_TYPE_GEN4_PLL4:
 		mult = cpg_pll_config->pll4_mult;
 		div = cpg_pll_config->pll4_div;
 		break;

 	case CLK_TYPE_GEN4_PLL5:
 		mult = cpg_pll_config->pll5_mult;
 		div = cpg_pll_config->pll5_div;
 		break;

 	case CLK_TYPE_GEN4_PLL6:
 		mult = cpg_pll_config->pll6_mult;
 		div = cpg_pll_config->pll6_div;
 		break;

 	case CLK_TYPE_GEN4_PLL2X_3X:
 		value = readl(base + core->offset);
 		mult = (((value >> 24) & 0x7f) + 1) * 2;
 		break;

 	case CLK_TYPE_GEN4_Z:
 		return cpg_z_clk_register(core->name, __clk_get_name(parent),
 					  base, core->div, core->offset);

 	case CLK_TYPE_GEN4_SDSRC:
 		div = ((readl(base + SD0CKCR1) >> 29) & 0x03) + 4;
 		break;

 	case CLK_TYPE_GEN4_SDH:
 		return cpg_sdh_clk_register(core->name, base + core->offset,
 					   __clk_get_name(parent), notifiers);

 	case CLK_TYPE_GEN4_SD:
 		return cpg_sd_clk_register(core->name, base + core->offset,
 					   __clk_get_name(parent));

 	case CLK_TYPE_GEN4_MDSEL:
 		/*
 		 * Clock selectable between two parents and two fixed dividers
 		 * using a mode pin
 		 */
 		if (cpg_mode & BIT(core->offset)) {
 			div = core->div & 0xffff;
 		} else {
 			parent = clks[core->parent >> 16];
 			if (IS_ERR(parent))
 				return ERR_CAST(parent);
 			div = core->div >> 16;
 		}
 		mult = 1;
 		break;

 	case CLK_TYPE_GEN4_OSC:
 		/*
 		 * Clock combining OSC EXTAL predivider and a fixed divider
 		 */
 		div = cpg_pll_config->osc_prediv * core->div;
 		break;

 	case CLK_TYPE_GEN4_RPCSRC:
 		return clk_register_divider_table(NULL, core->name,
 						  __clk_get_name(parent), 0,
 						  base + CPG_RPCCKCR, 3, 2, 0,
 						  cpg_rpcsrc_div_table,
 						  &cpg_lock);

 	case CLK_TYPE_GEN4_RPC:
 		return cpg_rpc_clk_register(core->name, base + CPG_RPCCKCR,
 					    __clk_get_name(parent), notifiers);

 	case CLK_TYPE_GEN4_RPCD2:
 		return cpg_rpcd2_clk_register(core->name, base + CPG_RPCCKCR,
 					      __clk_get_name(parent));

 	default:
 		return ERR_PTR(-EINVAL);
 	}

 	return clk_register_fixed_factor(NULL, core->name,
 					 __clk_get_name(parent), 0, mult, div);
 }

 int __init rcar_gen4_cpg_init(const struct rcar_gen4_cpg_pll_config *config,
 			      unsigned int clk_extalr, u32 mode)
 {
 	cpg_pll_config = config;
 	cpg_clk_extalr = clk_extalr;
 	cpg_mode = mode;

 	spin_lock_init(&cpg_lock);

 	return 0;
 }
	// SPDX-License-Identifier: GPL-2.0
	/*
	* R-Car Gen4 Clock Pulse Generator
	*
	* Copyright (C) 2021 Renesas Electronics Corp.
	*
	* Based on rcar-gen3-cpg.c
	*
	* Copyright (C) 2015-2018 Glider bvba
	* Copyright (C) 2019 Renesas Electronics Corp.
	*/

	#include <linux/bitfield.h>
	#include <linux/clk.h>
	#include <linux/clk-provider.h>
	#include <linux/device.h>
	#include <linux/err.h>
	#include <linux/init.h>
	#include <linux/io.h>
	#include <linux/slab.h>

	#include "renesas-cpg-mssr.h"
	#include "rcar-gen4-cpg.h"
	#include "rcar-cpg-lib.h"

	static const struct rcar_gen4_cpg_pll_config *cpg_pll_config __initconst;
	static unsigned int cpg_clk_extalr __initdata;
	static u32 cpg_mode __initdata;

	/*
	* Z0 Clock & Z1 Clock
	*/
	#define CPG_FRQCRB 0x00000804
	#define CPG_FRQCRB_KICK BIT(31)
	#define CPG_FRQCRC 0x00000808

	struct cpg_z_clk {
	struct clk_hw hw;
	void __iomem *reg;
	void __iomem *kick_reg;
	unsigned long max_rate; /* Maximum rate for normal mode */
	unsigned int fixed_div;
	u32 mask;
	};

	#define to_z_clk(_hw) container_of(_hw, struct cpg_z_clk, hw)

	static unsigned long cpg_z_clk_recalc_rate(struct clk_hw *hw,
	unsigned long parent_rate)
	{
	struct cpg_z_clk *zclk = to_z_clk(hw);
	unsigned int mult;
	u32 val;

	val = readl(zclk->reg) & zclk->mask;
	mult = 32 - (val >> __ffs(zclk->mask));

	return DIV_ROUND_CLOSEST_ULL((u64)parent_rate * mult,
	32 * zclk->fixed_div);
	}

	static int cpg_z_clk_determine_rate(struct clk_hw *hw,
	struct clk_rate_request *req)
	{
	struct cpg_z_clk *zclk = to_z_clk(hw);
	unsigned int min_mult, max_mult, mult;
	unsigned long rate, prate;

	rate = min(req->rate, req->max_rate);
	if (rate <= zclk->max_rate) {
	/* Set parent rate to initial value for normal modes */
	prate = zclk->max_rate;
	} else {
	/* Set increased parent rate for boost modes */
	prate = rate;
	}
	req->best_parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw),
	prate * zclk->fixed_div);

	prate = req->best_parent_rate / zclk->fixed_div;
	min_mult = max(div64_ul(req->min_rate * 32ULL, prate), 1ULL);
	max_mult = min(div64_ul(req->max_rate * 32ULL, prate), 32ULL);
	if (max_mult < min_mult)
	return -EINVAL;

	mult = DIV_ROUND_CLOSEST_ULL(rate * 32ULL, prate);
	mult = clamp(mult, min_mult, max_mult);

	req->rate = DIV_ROUND_CLOSEST_ULL((u64)prate * mult, 32);
	return 0;
	}

	static int cpg_z_clk_set_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long parent_rate)
	{
	struct cpg_z_clk *zclk = to_z_clk(hw);
	unsigned int mult;
	unsigned int i;

	mult = DIV64_U64_ROUND_CLOSEST(rate * 32ULL * zclk->fixed_div,
	parent_rate);
	mult = clamp(mult, 1U, 32U);

	if (readl(zclk->kick_reg) & CPG_FRQCRB_KICK)
	return -EBUSY;

	cpg_reg_modify(zclk->reg, zclk->mask, (32 - mult) << __ffs(zclk->mask));

	/*
	* Set KICK bit in FRQCRB to update hardware setting and wait for
	* clock change completion.
	*/
	cpg_reg_modify(zclk->kick_reg, 0, CPG_FRQCRB_KICK);

	/*
	* Note: There is no HW information about the worst case latency.
	*
	* Using experimental measurements, it seems that no more than
	* ~10 iterations are needed, independently of the CPU rate.
	* Since this value might be dependent on external xtal rate, pll1
	* rate or even the other emulation clocks rate, use 1000 as a
	* "super" safe value.
	*/
	for (i = 1000; i; i--) {
	if (!(readl(zclk->kick_reg) & CPG_FRQCRB_KICK))
	return 0;

	cpu_relax();
	}

	return -ETIMEDOUT;
	}

	static const struct clk_ops cpg_z_clk_ops = {
	.recalc_rate = cpg_z_clk_recalc_rate,
	.determine_rate = cpg_z_clk_determine_rate,
	.set_rate = cpg_z_clk_set_rate,
	};

	static struct clk * __init cpg_z_clk_register(const char *name,
	const char *parent_name,
	void __iomem *reg,
	unsigned int div,
	unsigned int offset)
	{
	struct clk_init_data init = {};
	struct cpg_z_clk *zclk;
	struct clk *clk;

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

	init.name = name;
	init.ops = &cpg_z_clk_ops;
	init.flags = CLK_SET_RATE_PARENT;
	init.parent_names = &parent_name;
	init.num_parents = 1;

	zclk->reg = reg + CPG_FRQCRC;
	zclk->kick_reg = reg + CPG_FRQCRB;
	zclk->hw.init = &init;
	zclk->mask = GENMASK(offset + 4, offset);
	zclk->fixed_div = div; /* PLLVCO x 1/div x SYS-CPU divider */

	clk = clk_register(NULL, &zclk->hw);
	if (IS_ERR(clk)) {
	kfree(zclk);
	return clk;
	}

	zclk->max_rate = clk_hw_get_rate(clk_hw_get_parent(&zclk->hw)) /
	zclk->fixed_div;
	return clk;
	}

	/*
	* RPC Clocks
	*/
	static const struct clk_div_table cpg_rpcsrc_div_table[] = {
	{ 0, 4 }, { 1, 6 }, { 2, 5 }, { 3, 6 }, { 0, 0 },
	};

	struct clk * __init rcar_gen4_cpg_clk_register(struct device *dev,
	const struct cpg_core_clk core, const struct cpg_mssr_info info,
	struct clk *clks, void __iomem base,
	struct raw_notifier_head *notifiers)
	{
	const struct clk *parent;
	unsigned int mult = 1;
	unsigned int div = 1;
	u32 value;

	parent = clks[core->parent & 0xffff]; /* some types use high bits */
	if (IS_ERR(parent))
	return ERR_CAST(parent);

	switch (core->type) {
	case CLK_TYPE_GEN4_MAIN:
	div = cpg_pll_config->extal_div;
	break;

	case CLK_TYPE_GEN4_PLL1:
	mult = cpg_pll_config->pll1_mult;
	div = cpg_pll_config->pll1_div;
	break;

	case CLK_TYPE_GEN4_PLL2:
	mult = cpg_pll_config->pll2_mult;
	div = cpg_pll_config->pll2_div;
	break;

	case CLK_TYPE_GEN4_PLL3:
	mult = cpg_pll_config->pll3_mult;
	div = cpg_pll_config->pll3_div;
	break;

	case CLK_TYPE_GEN4_PLL4:
	mult = cpg_pll_config->pll4_mult;
	div = cpg_pll_config->pll4_div;
	break;

	case CLK_TYPE_GEN4_PLL5:
	mult = cpg_pll_config->pll5_mult;
	div = cpg_pll_config->pll5_div;
	break;

	case CLK_TYPE_GEN4_PLL6:
	mult = cpg_pll_config->pll6_mult;
	div = cpg_pll_config->pll6_div;
	break;

	case CLK_TYPE_GEN4_PLL2X_3X:
	value = readl(base + core->offset);
	mult = (((value >> 24) & 0x7f) + 1) * 2;
	break;

	case CLK_TYPE_GEN4_Z:
	return cpg_z_clk_register(core->name, __clk_get_name(parent),
	base, core->div, core->offset);

	case CLK_TYPE_GEN4_SDSRC:
	div = ((readl(base + SD0CKCR1) >> 29) & 0x03) + 4;
	break;

	case CLK_TYPE_GEN4_SDH:
	return cpg_sdh_clk_register(core->name, base + core->offset,
	__clk_get_name(parent), notifiers);

	case CLK_TYPE_GEN4_SD:
	return cpg_sd_clk_register(core->name, base + core->offset,
	__clk_get_name(parent));

	case CLK_TYPE_GEN4_MDSEL:
	/*
	* Clock selectable between two parents and two fixed dividers
	* using a mode pin
	*/
	if (cpg_mode & BIT(core->offset)) {
	div = core->div & 0xffff;
	} else {
	parent = clks[core->parent >> 16];
	if (IS_ERR(parent))
	return ERR_CAST(parent);
	div = core->div >> 16;
	}
	mult = 1;
	break;

	case CLK_TYPE_GEN4_OSC:
	/*
	* Clock combining OSC EXTAL predivider and a fixed divider
	*/
	div = cpg_pll_config->osc_prediv * core->div;
	break;

	case CLK_TYPE_GEN4_RPCSRC:
	return clk_register_divider_table(NULL, core->name,
	__clk_get_name(parent), 0,
	base + CPG_RPCCKCR, 3, 2, 0,
	cpg_rpcsrc_div_table,
	&cpg_lock);

	case CLK_TYPE_GEN4_RPC:
	return cpg_rpc_clk_register(core->name, base + CPG_RPCCKCR,
	__clk_get_name(parent), notifiers);

	case CLK_TYPE_GEN4_RPCD2:
	return cpg_rpcd2_clk_register(core->name, base + CPG_RPCCKCR,
	__clk_get_name(parent));

	default:
	return ERR_PTR(-EINVAL);
	}

	return clk_register_fixed_factor(NULL, core->name,
	__clk_get_name(parent), 0, mult, div);
	}

	int __init rcar_gen4_cpg_init(const struct rcar_gen4_cpg_pll_config *config,
	unsigned int clk_extalr, u32 mode)
	{
	cpg_pll_config = config;
	cpg_clk_extalr = clk_extalr;
	cpg_mode = mode;

	spin_lock_init(&cpg_lock);

	return 0;
	}