drivers/clk/microchip/clk-mpfs.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * PolarFire SoC MSS/core complex clock control
  *
  * Copyright (C) 2020-2022 Microchip Technology Inc. All rights reserved.
  */
 #include <linux/auxiliary_bus.h>
 #include <linux/clk-provider.h>
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <dt-bindings/clock/microchip,mpfs-clock.h>
 #include <soc/microchip/mpfs.h>

 /* address offset of control registers */
 #define REG_MSSPLL_REF_CR	0x08u
 #define REG_MSSPLL_POSTDIV_CR	0x10u
 #define REG_MSSPLL_SSCG_2_CR	0x2Cu
 #define REG_CLOCK_CONFIG_CR	0x08u
 #define REG_RTC_CLOCK_CR	0x0Cu
 #define REG_SUBBLK_CLOCK_CR	0x84u
 #define REG_SUBBLK_RESET_CR	0x88u

 #define MSSPLL_FBDIV_SHIFT	0x00u
 #define MSSPLL_FBDIV_WIDTH	0x0Cu
 #define MSSPLL_REFDIV_SHIFT	0x08u
 #define MSSPLL_REFDIV_WIDTH	0x06u
 #define MSSPLL_POSTDIV_SHIFT	0x08u
 #define MSSPLL_POSTDIV_WIDTH	0x07u
 #define MSSPLL_FIXED_DIV	4u

 struct mpfs_clock_data {
 	struct device *dev;
 	void __iomem *base;
 	void __iomem *msspll_base;
 	struct clk_hw_onecell_data hw_data;
 };

 struct mpfs_msspll_hw_clock {
 	void __iomem *base;
 	unsigned int id;
 	u32 reg_offset;
 	u32 shift;
 	u32 width;
 	u32 flags;
 	struct clk_hw hw;
 	struct clk_init_data init;
 };

 #define to_mpfs_msspll_clk(_hw) container_of(_hw, struct mpfs_msspll_hw_clock, hw)

 struct mpfs_cfg_hw_clock {
 	struct clk_divider cfg;
 	struct clk_init_data init;
 	unsigned int id;
 	u32 reg_offset;
 };

 struct mpfs_periph_hw_clock {
 	struct clk_gate periph;
 	unsigned int id;
 };

 /*
  * mpfs_clk_lock prevents anything else from writing to the
  * mpfs clk block while a software locked register is being written.
  */
 static DEFINE_SPINLOCK(mpfs_clk_lock);

 static const struct clk_parent_data mpfs_ext_ref[] = {
 	{ .index = 0 },
 };

 static const struct clk_div_table mpfs_div_cpu_axi_table[] = {
 	{ 0, 1 }, { 1, 2 }, { 2, 4 }, { 3, 8 },
 	{ 0, 0 }
 };

 static const struct clk_div_table mpfs_div_ahb_table[] = {
 	{ 1, 2 }, { 2, 4}, { 3, 8 },
 	{ 0, 0 }
 };

 /*
  * The only two supported reference clock frequencies for the PolarFire SoC are
  * 100 and 125 MHz, as the rtc reference is required to be 1 MHz.
  * It therefore only needs to have divider table entries corresponding to
  * divide by 100 and 125.
  */
 static const struct clk_div_table mpfs_div_rtcref_table[] = {
 	{ 100, 100 }, { 125, 125 },
 	{ 0, 0 }
 };

 static unsigned long mpfs_clk_msspll_recalc_rate(struct clk_hw *hw, unsigned long prate)
 {
 	struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
 	void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
 	void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
 	void __iomem *postdiv_addr = msspll_hw->base + REG_MSSPLL_POSTDIV_CR;
 	u32 mult, ref_div, postdiv;

 	mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
 	mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
 	ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
 	ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);
 	postdiv = readl_relaxed(postdiv_addr) >> MSSPLL_POSTDIV_SHIFT;
 	postdiv &= clk_div_mask(MSSPLL_POSTDIV_WIDTH);

 	return prate * mult / (ref_div * MSSPLL_FIXED_DIV * postdiv);
 }

 static long mpfs_clk_msspll_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate)
 {
 	struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
 	void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
 	void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
 	u32 mult, ref_div;
 	unsigned long rate_before_ctrl;

 	mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
 	mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
 	ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
 	ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);

 	rate_before_ctrl = rate * (ref_div * MSSPLL_FIXED_DIV) / mult;

 	return divider_round_rate(hw, rate_before_ctrl, prate, NULL, MSSPLL_POSTDIV_WIDTH,
 				  msspll_hw->flags);
 }

 static int mpfs_clk_msspll_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long prate)
 {
 	struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
 	void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
 	void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
 	void __iomem *postdiv_addr = msspll_hw->base + REG_MSSPLL_POSTDIV_CR;
 	u32 mult, ref_div, postdiv;
 	int divider_setting;
 	unsigned long rate_before_ctrl, flags;

 	mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
 	mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
 	ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
 	ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);

 	rate_before_ctrl = rate * (ref_div * MSSPLL_FIXED_DIV) / mult;
 	divider_setting = divider_get_val(rate_before_ctrl, prate, NULL, MSSPLL_POSTDIV_WIDTH,
 					  msspll_hw->flags);

 	if (divider_setting < 0)
 		return divider_setting;

 	spin_lock_irqsave(&mpfs_clk_lock, flags);

 	postdiv = readl_relaxed(postdiv_addr);
 	postdiv &= ~(clk_div_mask(MSSPLL_POSTDIV_WIDTH) << MSSPLL_POSTDIV_SHIFT);
 	writel_relaxed(postdiv, postdiv_addr);

 	spin_unlock_irqrestore(&mpfs_clk_lock, flags);

 	return 0;
 }

 static const struct clk_ops mpfs_clk_msspll_ops = {
 	.recalc_rate = mpfs_clk_msspll_recalc_rate,
 	.round_rate = mpfs_clk_msspll_round_rate,
 	.set_rate = mpfs_clk_msspll_set_rate,
 };

 #define CLK_PLL(_id, _name, _parent, _shift, _width, _flags, _offset) {			\
 	.id = _id,									\
 	.shift = _shift,								\
 	.width = _width,								\
 	.reg_offset = _offset,								\
 	.flags = _flags,								\
 	.hw.init = CLK_HW_INIT_PARENTS_DATA(_name, _parent, &mpfs_clk_msspll_ops, 0),	\
 }

 static struct mpfs_msspll_hw_clock mpfs_msspll_clks[] = {
 	CLK_PLL(CLK_MSSPLL, "clk_msspll", mpfs_ext_ref, MSSPLL_FBDIV_SHIFT,
 		MSSPLL_FBDIV_WIDTH, 0, REG_MSSPLL_SSCG_2_CR),
 };

 static int mpfs_clk_register_mssplls(struct device *dev, struct mpfs_msspll_hw_clock *msspll_hws,
 				     unsigned int num_clks, struct mpfs_clock_data *data)
 {
 	unsigned int i;
 	int ret;

 	for (i = 0; i < num_clks; i++) {
 		struct mpfs_msspll_hw_clock *msspll_hw = &msspll_hws[i];

 		msspll_hw->base = data->msspll_base;
 		ret = devm_clk_hw_register(dev, &msspll_hw->hw);
 		if (ret)
 			return dev_err_probe(dev, ret, "failed to register msspll id: %d\n",
 					     CLK_MSSPLL);

 		data->hw_data.hws[msspll_hw->id] = &msspll_hw->hw;
 	}

 	return 0;
 }

 /*
  * "CFG" clocks
  */

 #define CLK_CFG(_id, _name, _parent, _shift, _width, _table, _flags, _offset) {		\
 	.id = _id,									\
 	.cfg.shift = _shift,								\
 	.cfg.width = _width,								\
 	.cfg.table = _table,								\
 	.reg_offset = _offset,								\
 	.cfg.flags = _flags,								\
 	.cfg.hw.init = CLK_HW_INIT(_name, _parent, &clk_divider_ops, 0),		\
 	.cfg.lock = &mpfs_clk_lock,							\
 }

 #define CLK_CPU_OFFSET		0u
 #define CLK_AXI_OFFSET		1u
 #define CLK_AHB_OFFSET		2u
 #define CLK_RTCREF_OFFSET	3u

 static struct mpfs_cfg_hw_clock mpfs_cfg_clks[] = {
 	CLK_CFG(CLK_CPU, "clk_cpu", "clk_msspll", 0, 2, mpfs_div_cpu_axi_table, 0,
 		REG_CLOCK_CONFIG_CR),
 	CLK_CFG(CLK_AXI, "clk_axi", "clk_msspll", 2, 2, mpfs_div_cpu_axi_table, 0,
 		REG_CLOCK_CONFIG_CR),
 	CLK_CFG(CLK_AHB, "clk_ahb", "clk_msspll", 4, 2, mpfs_div_ahb_table, 0,
 		REG_CLOCK_CONFIG_CR),
 	{
 		.id = CLK_RTCREF,
 		.cfg.shift = 0,
 		.cfg.width = 12,
 		.cfg.table = mpfs_div_rtcref_table,
 		.reg_offset = REG_RTC_CLOCK_CR,
 		.cfg.flags = CLK_DIVIDER_ONE_BASED,
 		.cfg.hw.init =
 			CLK_HW_INIT_PARENTS_DATA("clk_rtcref", mpfs_ext_ref, &clk_divider_ops, 0),
 	}
 };

 static int mpfs_clk_register_cfgs(struct device *dev, struct mpfs_cfg_hw_clock *cfg_hws,
 				  unsigned int num_clks, struct mpfs_clock_data *data)
 {
 	unsigned int i, id;
 	int ret;

 	for (i = 0; i < num_clks; i++) {
 		struct mpfs_cfg_hw_clock *cfg_hw = &cfg_hws[i];

 		cfg_hw->cfg.reg = data->base + cfg_hw->reg_offset;
 		ret = devm_clk_hw_register(dev, &cfg_hw->cfg.hw);
 		if (ret)
 			return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
 					     cfg_hw->id);

 		id = cfg_hw->id;
 		data->hw_data.hws[id] = &cfg_hw->cfg.hw;
 	}

 	return 0;
 }

 /*
  * peripheral clocks - devices connected to axi or ahb buses.
  */

 #define CLK_PERIPH(_id, _name, _parent, _shift, _flags) {			\
 	.id = _id,								\
 	.periph.bit_idx = _shift,						\
 	.periph.hw.init = CLK_HW_INIT_HW(_name, _parent, &clk_gate_ops,		\
 				  _flags),					\
 	.periph.lock = &mpfs_clk_lock,						\
 }

 #define PARENT_CLK(PARENT) (&mpfs_cfg_clks[CLK_##PARENT##_OFFSET].cfg.hw)

 /*
  * Critical clocks:
  * - CLK_ENVM: reserved by hart software services (hss) superloop monitor/m mode interrupt
  *   trap handler
  * - CLK_MMUART0: reserved by the hss
  * - CLK_DDRC: provides clock to the ddr subsystem
  * - CLK_RTC: the onboard RTC's AHB bus clock must be kept running as the rtc will stop
  *   if the AHB interface clock is disabled
  * - CLK_FICx: these provide the processor side clocks to the "FIC" (Fabric InterConnect)
  *   clock domain crossers which provide the interface to the FPGA fabric. Disabling them
  *   causes the FPGA fabric to go into reset.
  * - CLK_ATHENA: The athena clock is FIC4, which is reserved for the Athena TeraFire.
  */

 static struct mpfs_periph_hw_clock mpfs_periph_clks[] = {
 	CLK_PERIPH(CLK_ENVM, "clk_periph_envm", PARENT_CLK(AHB), 0, CLK_IS_CRITICAL),
 	CLK_PERIPH(CLK_MAC0, "clk_periph_mac0", PARENT_CLK(AHB), 1, 0),
 	CLK_PERIPH(CLK_MAC1, "clk_periph_mac1", PARENT_CLK(AHB), 2, 0),
 	CLK_PERIPH(CLK_MMC, "clk_periph_mmc", PARENT_CLK(AHB), 3, 0),
 	CLK_PERIPH(CLK_TIMER, "clk_periph_timer", PARENT_CLK(RTCREF), 4, 0),
 	CLK_PERIPH(CLK_MMUART0, "clk_periph_mmuart0", PARENT_CLK(AHB), 5, CLK_IS_CRITICAL),
 	CLK_PERIPH(CLK_MMUART1, "clk_periph_mmuart1", PARENT_CLK(AHB), 6, 0),
 	CLK_PERIPH(CLK_MMUART2, "clk_periph_mmuart2", PARENT_CLK(AHB), 7, 0),
 	CLK_PERIPH(CLK_MMUART3, "clk_periph_mmuart3", PARENT_CLK(AHB), 8, 0),
 	CLK_PERIPH(CLK_MMUART4, "clk_periph_mmuart4", PARENT_CLK(AHB), 9, 0),
 	CLK_PERIPH(CLK_SPI0, "clk_periph_spi0", PARENT_CLK(AHB), 10, 0),
 	CLK_PERIPH(CLK_SPI1, "clk_periph_spi1", PARENT_CLK(AHB), 11, 0),
 	CLK_PERIPH(CLK_I2C0, "clk_periph_i2c0", PARENT_CLK(AHB), 12, 0),
 	CLK_PERIPH(CLK_I2C1, "clk_periph_i2c1", PARENT_CLK(AHB), 13, 0),
 	CLK_PERIPH(CLK_CAN0, "clk_periph_can0", PARENT_CLK(AHB), 14, 0),
 	CLK_PERIPH(CLK_CAN1, "clk_periph_can1", PARENT_CLK(AHB), 15, 0),
 	CLK_PERIPH(CLK_USB, "clk_periph_usb", PARENT_CLK(AHB), 16, 0),
 	CLK_PERIPH(CLK_RTC, "clk_periph_rtc", PARENT_CLK(AHB), 18, CLK_IS_CRITICAL),
 	CLK_PERIPH(CLK_QSPI, "clk_periph_qspi", PARENT_CLK(AHB), 19, 0),
 	CLK_PERIPH(CLK_GPIO0, "clk_periph_gpio0", PARENT_CLK(AHB), 20, 0),
 	CLK_PERIPH(CLK_GPIO1, "clk_periph_gpio1", PARENT_CLK(AHB), 21, 0),
 	CLK_PERIPH(CLK_GPIO2, "clk_periph_gpio2", PARENT_CLK(AHB), 22, 0),
 	CLK_PERIPH(CLK_DDRC, "clk_periph_ddrc", PARENT_CLK(AHB), 23, CLK_IS_CRITICAL),
 	CLK_PERIPH(CLK_FIC0, "clk_periph_fic0", PARENT_CLK(AXI), 24, CLK_IS_CRITICAL),
 	CLK_PERIPH(CLK_FIC1, "clk_periph_fic1", PARENT_CLK(AXI), 25, CLK_IS_CRITICAL),
 	CLK_PERIPH(CLK_FIC2, "clk_periph_fic2", PARENT_CLK(AXI), 26, CLK_IS_CRITICAL),
 	CLK_PERIPH(CLK_FIC3, "clk_periph_fic3", PARENT_CLK(AXI), 27, CLK_IS_CRITICAL),
 	CLK_PERIPH(CLK_ATHENA, "clk_periph_athena", PARENT_CLK(AXI), 28, CLK_IS_CRITICAL),
 	CLK_PERIPH(CLK_CFM, "clk_periph_cfm", PARENT_CLK(AHB), 29, 0),
 };

 static int mpfs_clk_register_periphs(struct device *dev, struct mpfs_periph_hw_clock *periph_hws,
 				     int num_clks, struct mpfs_clock_data *data)
 {
 	unsigned int i, id;
 	int ret;

 	for (i = 0; i < num_clks; i++) {
 		struct mpfs_periph_hw_clock *periph_hw = &periph_hws[i];

 		periph_hw->periph.reg = data->base + REG_SUBBLK_CLOCK_CR;
 		ret = devm_clk_hw_register(dev, &periph_hw->periph.hw);
 		if (ret)
 			return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
 					     periph_hw->id);

 		id = periph_hws[i].id;
 		data->hw_data.hws[id] = &periph_hw->periph.hw;
 	}

 	return 0;
 }

 /*
  * Peripheral clock resets
  */

 #if IS_ENABLED(CONFIG_RESET_CONTROLLER)

 u32 mpfs_reset_read(struct device *dev)
 {
 	struct mpfs_clock_data *clock_data = dev_get_drvdata(dev->parent);

 	return readl_relaxed(clock_data->base + REG_SUBBLK_RESET_CR);
 }
 EXPORT_SYMBOL_NS_GPL(mpfs_reset_read, MCHP_CLK_MPFS);

 void mpfs_reset_write(struct device *dev, u32 val)
 {
 	struct mpfs_clock_data *clock_data = dev_get_drvdata(dev->parent);

 	writel_relaxed(val, clock_data->base + REG_SUBBLK_RESET_CR);
 }
 EXPORT_SYMBOL_NS_GPL(mpfs_reset_write, MCHP_CLK_MPFS);

 static void mpfs_reset_unregister_adev(void *_adev)
 {
 	struct auxiliary_device *adev = _adev;

 	auxiliary_device_delete(adev);
 }

 static void mpfs_reset_adev_release(struct device *dev)
 {
 	struct auxiliary_device *adev = to_auxiliary_dev(dev);

 	auxiliary_device_uninit(adev);

 	kfree(adev);
 }

 static struct auxiliary_device *mpfs_reset_adev_alloc(struct mpfs_clock_data *clk_data)
 {
 	struct auxiliary_device *adev;
 	int ret;

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

 	adev->name = "reset-mpfs";
 	adev->dev.parent = clk_data->dev;
 	adev->dev.release = mpfs_reset_adev_release;
 	adev->id = 666u;

 	ret = auxiliary_device_init(adev);
 	if (ret) {
 		kfree(adev);
 		return ERR_PTR(ret);
 	}

 	return adev;
 }

 static int mpfs_reset_controller_register(struct mpfs_clock_data *clk_data)
 {
 	struct auxiliary_device *adev;
 	int ret;

 	adev = mpfs_reset_adev_alloc(clk_data);
 	if (IS_ERR(adev))
 		return PTR_ERR(adev);

 	ret = auxiliary_device_add(adev);
 	if (ret) {
 		auxiliary_device_uninit(adev);
 		return ret;
 	}

 	return devm_add_action_or_reset(clk_data->dev, mpfs_reset_unregister_adev, adev);
 }

 #else /* !CONFIG_RESET_CONTROLLER */

 static int mpfs_reset_controller_register(struct mpfs_clock_data *clk_data)
 {
 	return 0;
 }

 #endif /* !CONFIG_RESET_CONTROLLER */

 static int mpfs_clk_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct mpfs_clock_data *clk_data;
 	unsigned int num_clks;
 	int ret;

 	/* CLK_RESERVED is not part of clock arrays, so add 1 */
 	num_clks = ARRAY_SIZE(mpfs_msspll_clks) + ARRAY_SIZE(mpfs_cfg_clks)
 		   + ARRAY_SIZE(mpfs_periph_clks) + 1;

 	clk_data = devm_kzalloc(dev, struct_size(clk_data, hw_data.hws, num_clks), GFP_KERNEL);
 	if (!clk_data)
 		return -ENOMEM;

 	clk_data->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(clk_data->base))
 		return PTR_ERR(clk_data->base);

 	clk_data->msspll_base = devm_platform_ioremap_resource(pdev, 1);
 	if (IS_ERR(clk_data->msspll_base))
 		return PTR_ERR(clk_data->msspll_base);

 	clk_data->hw_data.num = num_clks;
 	clk_data->dev = dev;
 	dev_set_drvdata(dev, clk_data);

 	ret = mpfs_clk_register_mssplls(dev, mpfs_msspll_clks, ARRAY_SIZE(mpfs_msspll_clks),
 					clk_data);
 	if (ret)
 		return ret;

 	ret = mpfs_clk_register_cfgs(dev, mpfs_cfg_clks, ARRAY_SIZE(mpfs_cfg_clks), clk_data);
 	if (ret)
 		return ret;

 	ret = mpfs_clk_register_periphs(dev, mpfs_periph_clks, ARRAY_SIZE(mpfs_periph_clks),
 					clk_data);
 	if (ret)
 		return ret;

 	ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, &clk_data->hw_data);
 	if (ret)
 		return ret;

 	return mpfs_reset_controller_register(clk_data);
 }

 static const struct of_device_id mpfs_clk_of_match_table[] = {
 	{ .compatible = "microchip,mpfs-clkcfg", },
 	{}
 };
 MODULE_DEVICE_TABLE(of, mpfs_clk_of_match_table);

 static struct platform_driver mpfs_clk_driver = {
 	.probe = mpfs_clk_probe,
 	.driver	= {
 		.name = "microchip-mpfs-clkcfg",
 		.of_match_table = mpfs_clk_of_match_table,
 	},
 };

 static int __init clk_mpfs_init(void)
 {
 	return platform_driver_register(&mpfs_clk_driver);
 }
 core_initcall(clk_mpfs_init);

 static void __exit clk_mpfs_exit(void)
 {
 	platform_driver_unregister(&mpfs_clk_driver);
 }
 module_exit(clk_mpfs_exit);

 MODULE_DESCRIPTION("Microchip PolarFire SoC Clock Driver");
 MODULE_AUTHOR("Padmarao Begari <padmarao.begari@microchip.com>");
 MODULE_AUTHOR("Daire McNamara <daire.mcnamara@microchip.com>");
 MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* PolarFire SoC MSS/core complex clock control
	*
	* Copyright (C) 2020-2022 Microchip Technology Inc. All rights reserved.
	*/
	#include <linux/auxiliary_bus.h>
	#include <linux/clk-provider.h>
	#include <linux/io.h>
	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/slab.h>
	#include <dt-bindings/clock/microchip,mpfs-clock.h>
	#include <soc/microchip/mpfs.h>

	/* address offset of control registers */
	#define REG_MSSPLL_REF_CR 0x08u
	#define REG_MSSPLL_POSTDIV_CR 0x10u
	#define REG_MSSPLL_SSCG_2_CR 0x2Cu
	#define REG_CLOCK_CONFIG_CR 0x08u
	#define REG_RTC_CLOCK_CR 0x0Cu
	#define REG_SUBBLK_CLOCK_CR 0x84u
	#define REG_SUBBLK_RESET_CR 0x88u

	#define MSSPLL_FBDIV_SHIFT 0x00u
	#define MSSPLL_FBDIV_WIDTH 0x0Cu
	#define MSSPLL_REFDIV_SHIFT 0x08u
	#define MSSPLL_REFDIV_WIDTH 0x06u
	#define MSSPLL_POSTDIV_SHIFT 0x08u
	#define MSSPLL_POSTDIV_WIDTH 0x07u
	#define MSSPLL_FIXED_DIV 4u

	struct mpfs_clock_data {
	struct device *dev;
	void __iomem *base;
	void __iomem *msspll_base;
	struct clk_hw_onecell_data hw_data;
	};

	struct mpfs_msspll_hw_clock {
	void __iomem *base;
	unsigned int id;
	u32 reg_offset;
	u32 shift;
	u32 width;
	u32 flags;
	struct clk_hw hw;
	struct clk_init_data init;
	};

	#define to_mpfs_msspll_clk(_hw) container_of(_hw, struct mpfs_msspll_hw_clock, hw)

	struct mpfs_cfg_hw_clock {
	struct clk_divider cfg;
	struct clk_init_data init;
	unsigned int id;
	u32 reg_offset;
	};

	struct mpfs_periph_hw_clock {
	struct clk_gate periph;
	unsigned int id;
	};

	/*
	* mpfs_clk_lock prevents anything else from writing to the
	* mpfs clk block while a software locked register is being written.
	*/
	static DEFINE_SPINLOCK(mpfs_clk_lock);

	static const struct clk_parent_data mpfs_ext_ref[] = {
	{ .index = 0 },
	};

	static const struct clk_div_table mpfs_div_cpu_axi_table[] = {
	{ 0, 1 }, { 1, 2 }, { 2, 4 }, { 3, 8 },
	{ 0, 0 }
	};

	static const struct clk_div_table mpfs_div_ahb_table[] = {
	{ 1, 2 }, { 2, 4}, { 3, 8 },
	{ 0, 0 }
	};

	/*
	* The only two supported reference clock frequencies for the PolarFire SoC are
	* 100 and 125 MHz, as the rtc reference is required to be 1 MHz.
	* It therefore only needs to have divider table entries corresponding to
	* divide by 100 and 125.
	*/
	static const struct clk_div_table mpfs_div_rtcref_table[] = {
	{ 100, 100 }, { 125, 125 },
	{ 0, 0 }
	};

	static unsigned long mpfs_clk_msspll_recalc_rate(struct clk_hw *hw, unsigned long prate)
	{
	struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
	void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
	void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
	void __iomem *postdiv_addr = msspll_hw->base + REG_MSSPLL_POSTDIV_CR;
	u32 mult, ref_div, postdiv;

	mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
	mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
	ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
	ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);
	postdiv = readl_relaxed(postdiv_addr) >> MSSPLL_POSTDIV_SHIFT;
	postdiv &= clk_div_mask(MSSPLL_POSTDIV_WIDTH);

	return prate * mult / (ref_div * MSSPLL_FIXED_DIV * postdiv);
	}

	static long mpfs_clk_msspll_round_rate(struct clk_hw hw, unsigned long rate, unsigned long prate)
	{
	struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
	void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
	void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
	u32 mult, ref_div;
	unsigned long rate_before_ctrl;

	mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
	mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
	ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
	ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);

	rate_before_ctrl = rate * (ref_div * MSSPLL_FIXED_DIV) / mult;

	return divider_round_rate(hw, rate_before_ctrl, prate, NULL, MSSPLL_POSTDIV_WIDTH,
	msspll_hw->flags);
	}

	static int mpfs_clk_msspll_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long prate)
	{
	struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
	void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
	void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
	void __iomem *postdiv_addr = msspll_hw->base + REG_MSSPLL_POSTDIV_CR;
	u32 mult, ref_div, postdiv;
	int divider_setting;
	unsigned long rate_before_ctrl, flags;

	mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
	mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
	ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
	ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);

	rate_before_ctrl = rate * (ref_div * MSSPLL_FIXED_DIV) / mult;
	divider_setting = divider_get_val(rate_before_ctrl, prate, NULL, MSSPLL_POSTDIV_WIDTH,
	msspll_hw->flags);

	if (divider_setting < 0)
	return divider_setting;

	spin_lock_irqsave(&mpfs_clk_lock, flags);

	postdiv = readl_relaxed(postdiv_addr);
	postdiv &= ~(clk_div_mask(MSSPLL_POSTDIV_WIDTH) << MSSPLL_POSTDIV_SHIFT);
	writel_relaxed(postdiv, postdiv_addr);

	spin_unlock_irqrestore(&mpfs_clk_lock, flags);

	return 0;
	}

	static const struct clk_ops mpfs_clk_msspll_ops = {
	.recalc_rate = mpfs_clk_msspll_recalc_rate,
	.round_rate = mpfs_clk_msspll_round_rate,
	.set_rate = mpfs_clk_msspll_set_rate,
	};

	#define CLK_PLL(_id, _name, _parent, _shift, _width, _flags, _offset) { \
	.id = _id, \
	.shift = _shift, \
	.width = _width, \
	.reg_offset = _offset, \
	.flags = _flags, \
	.hw.init = CLK_HW_INIT_PARENTS_DATA(_name, _parent, &mpfs_clk_msspll_ops, 0), \
	}

	static struct mpfs_msspll_hw_clock mpfs_msspll_clks[] = {
	CLK_PLL(CLK_MSSPLL, "clk_msspll", mpfs_ext_ref, MSSPLL_FBDIV_SHIFT,
	MSSPLL_FBDIV_WIDTH, 0, REG_MSSPLL_SSCG_2_CR),
	};

	static int mpfs_clk_register_mssplls(struct device dev, struct mpfs_msspll_hw_clock msspll_hws,
	unsigned int num_clks, struct mpfs_clock_data *data)
	{
	unsigned int i;
	int ret;

	for (i = 0; i < num_clks; i++) {
	struct mpfs_msspll_hw_clock *msspll_hw = &msspll_hws[i];

	msspll_hw->base = data->msspll_base;
	ret = devm_clk_hw_register(dev, &msspll_hw->hw);
	if (ret)
	return dev_err_probe(dev, ret, "failed to register msspll id: %d\n",
	CLK_MSSPLL);

	data->hw_data.hws[msspll_hw->id] = &msspll_hw->hw;
	}

	return 0;
	}

	/*
	* "CFG" clocks
	*/

	#define CLK_CFG(_id, _name, _parent, _shift, _width, _table, _flags, _offset) { \
	.id = _id, \
	.cfg.shift = _shift, \
	.cfg.width = _width, \
	.cfg.table = _table, \
	.reg_offset = _offset, \
	.cfg.flags = _flags, \
	.cfg.hw.init = CLK_HW_INIT(_name, _parent, &clk_divider_ops, 0), \
	.cfg.lock = &mpfs_clk_lock, \
	}

	#define CLK_CPU_OFFSET 0u
	#define CLK_AXI_OFFSET 1u
	#define CLK_AHB_OFFSET 2u
	#define CLK_RTCREF_OFFSET 3u

	static struct mpfs_cfg_hw_clock mpfs_cfg_clks[] = {
	CLK_CFG(CLK_CPU, "clk_cpu", "clk_msspll", 0, 2, mpfs_div_cpu_axi_table, 0,
	REG_CLOCK_CONFIG_CR),
	CLK_CFG(CLK_AXI, "clk_axi", "clk_msspll", 2, 2, mpfs_div_cpu_axi_table, 0,
	REG_CLOCK_CONFIG_CR),
	CLK_CFG(CLK_AHB, "clk_ahb", "clk_msspll", 4, 2, mpfs_div_ahb_table, 0,
	REG_CLOCK_CONFIG_CR),
	{
	.id = CLK_RTCREF,
	.cfg.shift = 0,
	.cfg.width = 12,
	.cfg.table = mpfs_div_rtcref_table,
	.reg_offset = REG_RTC_CLOCK_CR,
	.cfg.flags = CLK_DIVIDER_ONE_BASED,
	.cfg.hw.init =
	CLK_HW_INIT_PARENTS_DATA("clk_rtcref", mpfs_ext_ref, &clk_divider_ops, 0),
	}
	};

	static int mpfs_clk_register_cfgs(struct device dev, struct mpfs_cfg_hw_clock cfg_hws,
	unsigned int num_clks, struct mpfs_clock_data *data)
	{
	unsigned int i, id;
	int ret;

	for (i = 0; i < num_clks; i++) {
	struct mpfs_cfg_hw_clock *cfg_hw = &cfg_hws[i];

	cfg_hw->cfg.reg = data->base + cfg_hw->reg_offset;
	ret = devm_clk_hw_register(dev, &cfg_hw->cfg.hw);
	if (ret)
	return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
	cfg_hw->id);

	id = cfg_hw->id;
	data->hw_data.hws[id] = &cfg_hw->cfg.hw;
	}

	return 0;
	}

	/*
	* peripheral clocks - devices connected to axi or ahb buses.
	*/

	#define CLK_PERIPH(_id, _name, _parent, _shift, _flags) { \
	.id = _id, \
	.periph.bit_idx = _shift, \
	.periph.hw.init = CLK_HW_INIT_HW(_name, _parent, &clk_gate_ops, \
	_flags), \
	.periph.lock = &mpfs_clk_lock, \
	}

	#define PARENT_CLK(PARENT) (&mpfs_cfg_clks[CLK_##PARENT##_OFFSET].cfg.hw)

	/*
	* Critical clocks:
	* - CLK_ENVM: reserved by hart software services (hss) superloop monitor/m mode interrupt
	* trap handler
	* - CLK_MMUART0: reserved by the hss
	* - CLK_DDRC: provides clock to the ddr subsystem
	* - CLK_RTC: the onboard RTC's AHB bus clock must be kept running as the rtc will stop
	* if the AHB interface clock is disabled
	* - CLK_FICx: these provide the processor side clocks to the "FIC" (Fabric InterConnect)
	* clock domain crossers which provide the interface to the FPGA fabric. Disabling them
	* causes the FPGA fabric to go into reset.
	* - CLK_ATHENA: The athena clock is FIC4, which is reserved for the Athena TeraFire.
	*/

	static struct mpfs_periph_hw_clock mpfs_periph_clks[] = {
	CLK_PERIPH(CLK_ENVM, "clk_periph_envm", PARENT_CLK(AHB), 0, CLK_IS_CRITICAL),
	CLK_PERIPH(CLK_MAC0, "clk_periph_mac0", PARENT_CLK(AHB), 1, 0),
	CLK_PERIPH(CLK_MAC1, "clk_periph_mac1", PARENT_CLK(AHB), 2, 0),
	CLK_PERIPH(CLK_MMC, "clk_periph_mmc", PARENT_CLK(AHB), 3, 0),
	CLK_PERIPH(CLK_TIMER, "clk_periph_timer", PARENT_CLK(RTCREF), 4, 0),
	CLK_PERIPH(CLK_MMUART0, "clk_periph_mmuart0", PARENT_CLK(AHB), 5, CLK_IS_CRITICAL),
	CLK_PERIPH(CLK_MMUART1, "clk_periph_mmuart1", PARENT_CLK(AHB), 6, 0),
	CLK_PERIPH(CLK_MMUART2, "clk_periph_mmuart2", PARENT_CLK(AHB), 7, 0),
	CLK_PERIPH(CLK_MMUART3, "clk_periph_mmuart3", PARENT_CLK(AHB), 8, 0),
	CLK_PERIPH(CLK_MMUART4, "clk_periph_mmuart4", PARENT_CLK(AHB), 9, 0),
	CLK_PERIPH(CLK_SPI0, "clk_periph_spi0", PARENT_CLK(AHB), 10, 0),
	CLK_PERIPH(CLK_SPI1, "clk_periph_spi1", PARENT_CLK(AHB), 11, 0),
	CLK_PERIPH(CLK_I2C0, "clk_periph_i2c0", PARENT_CLK(AHB), 12, 0),
	CLK_PERIPH(CLK_I2C1, "clk_periph_i2c1", PARENT_CLK(AHB), 13, 0),
	CLK_PERIPH(CLK_CAN0, "clk_periph_can0", PARENT_CLK(AHB), 14, 0),
	CLK_PERIPH(CLK_CAN1, "clk_periph_can1", PARENT_CLK(AHB), 15, 0),
	CLK_PERIPH(CLK_USB, "clk_periph_usb", PARENT_CLK(AHB), 16, 0),
	CLK_PERIPH(CLK_RTC, "clk_periph_rtc", PARENT_CLK(AHB), 18, CLK_IS_CRITICAL),
	CLK_PERIPH(CLK_QSPI, "clk_periph_qspi", PARENT_CLK(AHB), 19, 0),
	CLK_PERIPH(CLK_GPIO0, "clk_periph_gpio0", PARENT_CLK(AHB), 20, 0),
	CLK_PERIPH(CLK_GPIO1, "clk_periph_gpio1", PARENT_CLK(AHB), 21, 0),
	CLK_PERIPH(CLK_GPIO2, "clk_periph_gpio2", PARENT_CLK(AHB), 22, 0),
	CLK_PERIPH(CLK_DDRC, "clk_periph_ddrc", PARENT_CLK(AHB), 23, CLK_IS_CRITICAL),
	CLK_PERIPH(CLK_FIC0, "clk_periph_fic0", PARENT_CLK(AXI), 24, CLK_IS_CRITICAL),
	CLK_PERIPH(CLK_FIC1, "clk_periph_fic1", PARENT_CLK(AXI), 25, CLK_IS_CRITICAL),
	CLK_PERIPH(CLK_FIC2, "clk_periph_fic2", PARENT_CLK(AXI), 26, CLK_IS_CRITICAL),
	CLK_PERIPH(CLK_FIC3, "clk_periph_fic3", PARENT_CLK(AXI), 27, CLK_IS_CRITICAL),
	CLK_PERIPH(CLK_ATHENA, "clk_periph_athena", PARENT_CLK(AXI), 28, CLK_IS_CRITICAL),
	CLK_PERIPH(CLK_CFM, "clk_periph_cfm", PARENT_CLK(AHB), 29, 0),
	};

	static int mpfs_clk_register_periphs(struct device dev, struct mpfs_periph_hw_clock periph_hws,
	int num_clks, struct mpfs_clock_data *data)
	{
	unsigned int i, id;
	int ret;

	for (i = 0; i < num_clks; i++) {
	struct mpfs_periph_hw_clock *periph_hw = &periph_hws[i];

	periph_hw->periph.reg = data->base + REG_SUBBLK_CLOCK_CR;
	ret = devm_clk_hw_register(dev, &periph_hw->periph.hw);
	if (ret)
	return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
	periph_hw->id);

	id = periph_hws[i].id;
	data->hw_data.hws[id] = &periph_hw->periph.hw;
	}

	return 0;
	}

	/*
	* Peripheral clock resets
	*/

	#if IS_ENABLED(CONFIG_RESET_CONTROLLER)

	u32 mpfs_reset_read(struct device *dev)
	{
	struct mpfs_clock_data *clock_data = dev_get_drvdata(dev->parent);

	return readl_relaxed(clock_data->base + REG_SUBBLK_RESET_CR);
	}
	EXPORT_SYMBOL_NS_GPL(mpfs_reset_read, MCHP_CLK_MPFS);

	void mpfs_reset_write(struct device *dev, u32 val)
	{
	struct mpfs_clock_data *clock_data = dev_get_drvdata(dev->parent);

	writel_relaxed(val, clock_data->base + REG_SUBBLK_RESET_CR);
	}
	EXPORT_SYMBOL_NS_GPL(mpfs_reset_write, MCHP_CLK_MPFS);

	static void mpfs_reset_unregister_adev(void *_adev)
	{
	struct auxiliary_device *adev = _adev;

	auxiliary_device_delete(adev);
	}

	static void mpfs_reset_adev_release(struct device *dev)
	{
	struct auxiliary_device *adev = to_auxiliary_dev(dev);

	auxiliary_device_uninit(adev);

	kfree(adev);
	}

	static struct auxiliary_device mpfs_reset_adev_alloc(struct mpfs_clock_data clk_data)
	{
	struct auxiliary_device *adev;
	int ret;

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

	adev->name = "reset-mpfs";
	adev->dev.parent = clk_data->dev;
	adev->dev.release = mpfs_reset_adev_release;
	adev->id = 666u;

	ret = auxiliary_device_init(adev);
	if (ret) {
	kfree(adev);
	return ERR_PTR(ret);
	}

	return adev;
	}

	static int mpfs_reset_controller_register(struct mpfs_clock_data *clk_data)
	{
	struct auxiliary_device *adev;
	int ret;

	adev = mpfs_reset_adev_alloc(clk_data);
	if (IS_ERR(adev))
	return PTR_ERR(adev);

	ret = auxiliary_device_add(adev);
	if (ret) {
	auxiliary_device_uninit(adev);
	return ret;
	}

	return devm_add_action_or_reset(clk_data->dev, mpfs_reset_unregister_adev, adev);
	}

	#else /* !CONFIG_RESET_CONTROLLER */

	static int mpfs_reset_controller_register(struct mpfs_clock_data *clk_data)
	{
	return 0;
	}

	#endif /* !CONFIG_RESET_CONTROLLER */

	static int mpfs_clk_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct mpfs_clock_data *clk_data;
	unsigned int num_clks;
	int ret;

	/* CLK_RESERVED is not part of clock arrays, so add 1 */
	num_clks = ARRAY_SIZE(mpfs_msspll_clks) + ARRAY_SIZE(mpfs_cfg_clks)
	+ ARRAY_SIZE(mpfs_periph_clks) + 1;

	clk_data = devm_kzalloc(dev, struct_size(clk_data, hw_data.hws, num_clks), GFP_KERNEL);
	if (!clk_data)
	return -ENOMEM;

	clk_data->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(clk_data->base))
	return PTR_ERR(clk_data->base);

	clk_data->msspll_base = devm_platform_ioremap_resource(pdev, 1);
	if (IS_ERR(clk_data->msspll_base))
	return PTR_ERR(clk_data->msspll_base);

	clk_data->hw_data.num = num_clks;
	clk_data->dev = dev;
	dev_set_drvdata(dev, clk_data);

	ret = mpfs_clk_register_mssplls(dev, mpfs_msspll_clks, ARRAY_SIZE(mpfs_msspll_clks),
	clk_data);
	if (ret)
	return ret;

	ret = mpfs_clk_register_cfgs(dev, mpfs_cfg_clks, ARRAY_SIZE(mpfs_cfg_clks), clk_data);
	if (ret)
	return ret;

	ret = mpfs_clk_register_periphs(dev, mpfs_periph_clks, ARRAY_SIZE(mpfs_periph_clks),
	clk_data);
	if (ret)
	return ret;

	ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, &clk_data->hw_data);
	if (ret)
	return ret;

	return mpfs_reset_controller_register(clk_data);
	}

	static const struct of_device_id mpfs_clk_of_match_table[] = {
	{ .compatible = "microchip,mpfs-clkcfg", },
	{}
	};
	MODULE_DEVICE_TABLE(of, mpfs_clk_of_match_table);

	static struct platform_driver mpfs_clk_driver = {
	.probe = mpfs_clk_probe,
	.driver = {
	.name = "microchip-mpfs-clkcfg",
	.of_match_table = mpfs_clk_of_match_table,
	},
	};

	static int __init clk_mpfs_init(void)
	{
	return platform_driver_register(&mpfs_clk_driver);
	}
	core_initcall(clk_mpfs_init);

	static void __exit clk_mpfs_exit(void)
	{
	platform_driver_unregister(&mpfs_clk_driver);
	}
	module_exit(clk_mpfs_exit);

	MODULE_DESCRIPTION("Microchip PolarFire SoC Clock Driver");
	MODULE_AUTHOR("Padmarao Begari <padmarao.begari@microchip.com>");
	MODULE_AUTHOR("Daire McNamara <daire.mcnamara@microchip.com>");
	MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
	MODULE_LICENSE("GPL");