drivers/soc/renesas/rcar-sysc.c - arm/linux - Git at Google

 /*
  * R-Car SYSC Power management support
  *
  * Copyright (C) 2014  Magnus Damm
  * Copyright (C) 2015-2017 Glider bvba
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  */

 #include <linux/clk/renesas.h>
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/mm.h>
 #include <linux/of_address.h>
 #include <linux/pm_domain.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/io.h>
 #include <linux/soc/renesas/rcar-sysc.h>

 #include "rcar-sysc.h"

 /* SYSC Common */
 #define SYSCSR			0x00	/* SYSC Status Register */
 #define SYSCISR			0x04	/* Interrupt Status Register */
 #define SYSCISCR		0x08	/* Interrupt Status Clear Register */
 #define SYSCIER			0x0c	/* Interrupt Enable Register */
 #define SYSCIMR			0x10	/* Interrupt Mask Register */

 /* SYSC Status Register */
 #define SYSCSR_PONENB		1	/* Ready for power resume requests */
 #define SYSCSR_POFFENB		0	/* Ready for power shutoff requests */

 /*
  * Power Control Register Offsets inside the register block for each domain
  * Note: The "CR" registers for ARM cores exist on H1 only
  *	 Use WFI to power off, CPG/APMU to resume ARM cores on R-Car Gen2
  *	 Use PSCI on R-Car Gen3
  */
 #define PWRSR_OFFS		0x00	/* Power Status Register */
 #define PWROFFCR_OFFS		0x04	/* Power Shutoff Control Register */
 #define PWROFFSR_OFFS		0x08	/* Power Shutoff Status Register */
 #define PWRONCR_OFFS		0x0c	/* Power Resume Control Register */
 #define PWRONSR_OFFS		0x10	/* Power Resume Status Register */
 #define PWRER_OFFS		0x14	/* Power Shutoff/Resume Error */


 #define SYSCSR_RETRIES		100
 #define SYSCSR_DELAY_US		1

 #define PWRER_RETRIES		100
 #define PWRER_DELAY_US		1

 #define SYSCISR_RETRIES		1000
 #define SYSCISR_DELAY_US	1

 #define RCAR_PD_ALWAYS_ON	32	/* Always-on power area */

 static void __iomem *rcar_sysc_base;
 static DEFINE_SPINLOCK(rcar_sysc_lock); /* SMP CPUs + I/O devices */

 static int rcar_sysc_pwr_on_off(const struct rcar_sysc_ch *sysc_ch, bool on)
 {
 	unsigned int sr_bit, reg_offs;
 	int k;

 	if (on) {
 		sr_bit = SYSCSR_PONENB;
 		reg_offs = PWRONCR_OFFS;
 	} else {
 		sr_bit = SYSCSR_POFFENB;
 		reg_offs = PWROFFCR_OFFS;
 	}

 	/* Wait until SYSC is ready to accept a power request */
 	for (k = 0; k < SYSCSR_RETRIES; k++) {
 		if (ioread32(rcar_sysc_base + SYSCSR) & BIT(sr_bit))
 			break;
 		udelay(SYSCSR_DELAY_US);
 	}

 	if (k == SYSCSR_RETRIES)
 		return -EAGAIN;

 	/* Submit power shutoff or power resume request */
 	iowrite32(BIT(sysc_ch->chan_bit),
 		  rcar_sysc_base + sysc_ch->chan_offs + reg_offs);

 	return 0;
 }

 static int rcar_sysc_power(const struct rcar_sysc_ch *sysc_ch, bool on)
 {
 	unsigned int isr_mask = BIT(sysc_ch->isr_bit);
 	unsigned int chan_mask = BIT(sysc_ch->chan_bit);
 	unsigned int status;
 	unsigned long flags;
 	int ret = 0;
 	int k;

 	spin_lock_irqsave(&rcar_sysc_lock, flags);

 	iowrite32(isr_mask, rcar_sysc_base + SYSCISCR);

 	/* Submit power shutoff or resume request until it was accepted */
 	for (k = 0; k < PWRER_RETRIES; k++) {
 		ret = rcar_sysc_pwr_on_off(sysc_ch, on);
 		if (ret)
 			goto out;

 		status = ioread32(rcar_sysc_base +
 				  sysc_ch->chan_offs + PWRER_OFFS);
 		if (!(status & chan_mask))
 			break;

 		udelay(PWRER_DELAY_US);
 	}

 	if (k == PWRER_RETRIES) {
 		ret = -EIO;
 		goto out;
 	}

 	/* Wait until the power shutoff or resume request has completed * */
 	for (k = 0; k < SYSCISR_RETRIES; k++) {
 		if (ioread32(rcar_sysc_base + SYSCISR) & isr_mask)
 			break;
 		udelay(SYSCISR_DELAY_US);
 	}

 	if (k == SYSCISR_RETRIES)
 		ret = -EIO;

 	iowrite32(isr_mask, rcar_sysc_base + SYSCISCR);

  out:
 	spin_unlock_irqrestore(&rcar_sysc_lock, flags);

 	pr_debug("sysc power %s domain %d: %08x -> %d\n", on ? "on" : "off",
 		 sysc_ch->isr_bit, ioread32(rcar_sysc_base + SYSCISR), ret);
 	return ret;
 }

 int rcar_sysc_power_down(const struct rcar_sysc_ch *sysc_ch)
 {
 	return rcar_sysc_power(sysc_ch, false);
 }

 int rcar_sysc_power_up(const struct rcar_sysc_ch *sysc_ch)
 {
 	return rcar_sysc_power(sysc_ch, true);
 }

 static bool rcar_sysc_power_is_off(const struct rcar_sysc_ch *sysc_ch)
 {
 	unsigned int st;

 	st = ioread32(rcar_sysc_base + sysc_ch->chan_offs + PWRSR_OFFS);
 	if (st & BIT(sysc_ch->chan_bit))
 		return true;

 	return false;
 }

 struct rcar_sysc_pd {
 	struct generic_pm_domain genpd;
 	struct rcar_sysc_ch ch;
 	unsigned int flags;
 	char name[0];
 };

 static inline struct rcar_sysc_pd *to_rcar_pd(struct generic_pm_domain *d)
 {
 	return container_of(d, struct rcar_sysc_pd, genpd);
 }

 static int rcar_sysc_pd_power_off(struct generic_pm_domain *genpd)
 {
 	struct rcar_sysc_pd *pd = to_rcar_pd(genpd);

 	pr_debug("%s: %s\n", __func__, genpd->name);
 	return rcar_sysc_power_down(&pd->ch);
 }

 static int rcar_sysc_pd_power_on(struct generic_pm_domain *genpd)
 {
 	struct rcar_sysc_pd *pd = to_rcar_pd(genpd);

 	pr_debug("%s: %s\n", __func__, genpd->name);
 	return rcar_sysc_power_up(&pd->ch);
 }

 static bool has_cpg_mstp;

 static void __init rcar_sysc_pd_setup(struct rcar_sysc_pd *pd)
 {
 	struct generic_pm_domain *genpd = &pd->genpd;
 	const char *name = pd->genpd.name;
 	struct dev_power_governor *gov = &simple_qos_governor;

 	if (pd->flags & PD_CPU) {
 		/*
 		 * This domain contains a CPU core and therefore it should
 		 * only be turned off if the CPU is not in use.
 		 */
 		pr_debug("PM domain %s contains %s\n", name, "CPU");
 		genpd->flags |= GENPD_FLAG_ALWAYS_ON;
 	} else if (pd->flags & PD_SCU) {
 		/*
 		 * This domain contains an SCU and cache-controller, and
 		 * therefore it should only be turned off if the CPU cores are
 		 * not in use.
 		 */
 		pr_debug("PM domain %s contains %s\n", name, "SCU");
 		genpd->flags |= GENPD_FLAG_ALWAYS_ON;
 	} else if (pd->flags & PD_NO_CR) {
 		/*
 		 * This domain cannot be turned off.
 		 */
 		genpd->flags |= GENPD_FLAG_ALWAYS_ON;
 	}

 	if (!(pd->flags & (PD_CPU | PD_SCU))) {
 		/* Enable Clock Domain for I/O devices */
 		genpd->flags |= GENPD_FLAG_PM_CLK;
 		if (has_cpg_mstp) {
 			genpd->attach_dev = cpg_mstp_attach_dev;
 			genpd->detach_dev = cpg_mstp_detach_dev;
 		} else {
 			genpd->attach_dev = cpg_mssr_attach_dev;
 			genpd->detach_dev = cpg_mssr_detach_dev;
 		}
 	}

 	genpd->power_off = rcar_sysc_pd_power_off;
 	genpd->power_on = rcar_sysc_pd_power_on;

 	if (pd->flags & (PD_CPU | PD_NO_CR)) {
 		/* Skip CPUs (handled by SMP code) and areas without control */
 		pr_debug("%s: Not touching %s\n", __func__, genpd->name);
 		goto finalize;
 	}

 	if (!rcar_sysc_power_is_off(&pd->ch)) {
 		pr_debug("%s: %s is already powered\n", __func__, genpd->name);
 		goto finalize;
 	}

 	rcar_sysc_power_up(&pd->ch);

 finalize:
 	pm_genpd_init(genpd, gov, false);
 }

 static const struct of_device_id rcar_sysc_matches[] = {
 #ifdef CONFIG_SYSC_R8A7743
 	{ .compatible = "renesas,r8a7743-sysc", .data = &r8a7743_sysc_info },
 #endif
 #ifdef CONFIG_SYSC_R8A7745
 	{ .compatible = "renesas,r8a7745-sysc", .data = &r8a7745_sysc_info },
 #endif
 #ifdef CONFIG_SYSC_R8A7779
 	{ .compatible = "renesas,r8a7779-sysc", .data = &r8a7779_sysc_info },
 #endif
 #ifdef CONFIG_SYSC_R8A7790
 	{ .compatible = "renesas,r8a7790-sysc", .data = &r8a7790_sysc_info },
 #endif
 #ifdef CONFIG_SYSC_R8A7791
 	{ .compatible = "renesas,r8a7791-sysc", .data = &r8a7791_sysc_info },
 	/* R-Car M2-N is identical to R-Car M2-W w.r.t. power domains. */
 	{ .compatible = "renesas,r8a7793-sysc", .data = &r8a7791_sysc_info },
 #endif
 #ifdef CONFIG_SYSC_R8A7792
 	{ .compatible = "renesas,r8a7792-sysc", .data = &r8a7792_sysc_info },
 #endif
 #ifdef CONFIG_SYSC_R8A7794
 	{ .compatible = "renesas,r8a7794-sysc", .data = &r8a7794_sysc_info },
 #endif
 #ifdef CONFIG_SYSC_R8A7795
 	{ .compatible = "renesas,r8a7795-sysc", .data = &r8a7795_sysc_info },
 #endif
 #ifdef CONFIG_SYSC_R8A7796
 	{ .compatible = "renesas,r8a7796-sysc", .data = &r8a7796_sysc_info },
 #endif
 #ifdef CONFIG_SYSC_R8A77995
 	{ .compatible = "renesas,r8a77995-sysc", .data = &r8a77995_sysc_info },
 #endif
 	{ /* sentinel */ }
 };

 struct rcar_pm_domains {
 	struct genpd_onecell_data onecell_data;
 	struct generic_pm_domain *domains[RCAR_PD_ALWAYS_ON + 1];
 };

 static int __init rcar_sysc_pd_init(void)
 {
 	const struct rcar_sysc_info *info;
 	const struct of_device_id *match;
 	struct rcar_pm_domains *domains;
 	struct device_node *np;
 	u32 syscier, syscimr;
 	void __iomem *base;
 	unsigned int i;
 	int error;

 	if (rcar_sysc_base)
 		return 0;

 	np = of_find_matching_node_and_match(NULL, rcar_sysc_matches, &match);
 	if (!np)
 		return -ENODEV;

 	info = match->data;

 	if (info->init) {
 		error = info->init();
 		if (error)
 			return error;
 	}

 	has_cpg_mstp = of_find_compatible_node(NULL, NULL,
 					       "renesas,cpg-mstp-clocks");

 	base = of_iomap(np, 0);
 	if (!base) {
 		pr_warn("%pOF: Cannot map regs\n", np);
 		error = -ENOMEM;
 		goto out_put;
 	}

 	rcar_sysc_base = base;

 	domains = kzalloc(sizeof(*domains), GFP_KERNEL);
 	if (!domains) {
 		error = -ENOMEM;
 		goto out_put;
 	}

 	domains->onecell_data.domains = domains->domains;
 	domains->onecell_data.num_domains = ARRAY_SIZE(domains->domains);

 	for (i = 0, syscier = 0; i < info->num_areas; i++)
 		syscier |= BIT(info->areas[i].isr_bit);

 	/*
 	 * Mask all interrupt sources to prevent the CPU from receiving them.
 	 * Make sure not to clear reserved bits that were set before.
 	 */
 	syscimr = ioread32(base + SYSCIMR);
 	syscimr |= syscier;
 	pr_debug("%pOF: syscimr = 0x%08x\n", np, syscimr);
 	iowrite32(syscimr, base + SYSCIMR);

 	/*
 	 * SYSC needs all interrupt sources enabled to control power.
 	 */
 	pr_debug("%pOF: syscier = 0x%08x\n", np, syscier);
 	iowrite32(syscier, base + SYSCIER);

 	for (i = 0; i < info->num_areas; i++) {
 		const struct rcar_sysc_area *area = &info->areas[i];
 		struct rcar_sysc_pd *pd;

 		if (!area->name) {
 			/* Skip NULLified area */
 			continue;
 		}

 		pd = kzalloc(sizeof(*pd) + strlen(area->name) + 1, GFP_KERNEL);
 		if (!pd) {
 			error = -ENOMEM;
 			goto out_put;
 		}

 		strcpy(pd->name, area->name);
 		pd->genpd.name = pd->name;
 		pd->ch.chan_offs = area->chan_offs;
 		pd->ch.chan_bit = area->chan_bit;
 		pd->ch.isr_bit = area->isr_bit;
 		pd->flags = area->flags;

 		rcar_sysc_pd_setup(pd);
 		if (area->parent >= 0)
 			pm_genpd_add_subdomain(domains->domains[area->parent],
 					       &pd->genpd);

 		domains->domains[area->isr_bit] = &pd->genpd;
 	}

 	error = of_genpd_add_provider_onecell(np, &domains->onecell_data);

 out_put:
 	of_node_put(np);
 	return error;
 }
 early_initcall(rcar_sysc_pd_init);

 void __init rcar_sysc_nullify(struct rcar_sysc_area *areas,
 			      unsigned int num_areas, u8 id)
 {
 	unsigned int i;

 	for (i = 0; i < num_areas; i++)
 		if (areas[i].isr_bit == id) {
 			areas[i].name = NULL;
 			return;
 		}
 }

 void __init rcar_sysc_init(phys_addr_t base, u32 syscier)
 {
 	u32 syscimr;

 	if (!rcar_sysc_pd_init())
 		return;

 	rcar_sysc_base = ioremap_nocache(base, PAGE_SIZE);

 	/*
 	 * Mask all interrupt sources to prevent the CPU from receiving them.
 	 * Make sure not to clear reserved bits that were set before.
 	 */
 	syscimr = ioread32(rcar_sysc_base + SYSCIMR);
 	syscimr |= syscier;
 	pr_debug("%s: syscimr = 0x%08x\n", __func__, syscimr);
 	iowrite32(syscimr, rcar_sysc_base + SYSCIMR);

 	/*
 	 * SYSC needs all interrupt sources enabled to control power.
 	 */
 	pr_debug("%s: syscier = 0x%08x\n", __func__, syscier);
 	iowrite32(syscier, rcar_sysc_base + SYSCIER);
 }
	/*
	* R-Car SYSC Power management support
	*
	* Copyright (C) 2014 Magnus Damm
	* Copyright (C) 2015-2017 Glider bvba
	*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file "COPYING" in the main directory of this archive
	* for more details.
	*/

	#include <linux/clk/renesas.h>
	#include <linux/delay.h>
	#include <linux/err.h>
	#include <linux/mm.h>
	#include <linux/of_address.h>
	#include <linux/pm_domain.h>
	#include <linux/slab.h>
	#include <linux/spinlock.h>
	#include <linux/io.h>
	#include <linux/soc/renesas/rcar-sysc.h>

	#include "rcar-sysc.h"

	/* SYSC Common */
	#define SYSCSR 0x00 /* SYSC Status Register */
	#define SYSCISR 0x04 /* Interrupt Status Register */
	#define SYSCISCR 0x08 /* Interrupt Status Clear Register */
	#define SYSCIER 0x0c /* Interrupt Enable Register */
	#define SYSCIMR 0x10 /* Interrupt Mask Register */

	/* SYSC Status Register */
	#define SYSCSR_PONENB 1 /* Ready for power resume requests */
	#define SYSCSR_POFFENB 0 /* Ready for power shutoff requests */

	/*
	* Power Control Register Offsets inside the register block for each domain
	* Note: The "CR" registers for ARM cores exist on H1 only
	* Use WFI to power off, CPG/APMU to resume ARM cores on R-Car Gen2
	* Use PSCI on R-Car Gen3
	*/
	#define PWRSR_OFFS 0x00 /* Power Status Register */
	#define PWROFFCR_OFFS 0x04 /* Power Shutoff Control Register */
	#define PWROFFSR_OFFS 0x08 /* Power Shutoff Status Register */
	#define PWRONCR_OFFS 0x0c /* Power Resume Control Register */
	#define PWRONSR_OFFS 0x10 /* Power Resume Status Register */
	#define PWRER_OFFS 0x14 /* Power Shutoff/Resume Error */


	#define SYSCSR_RETRIES 100
	#define SYSCSR_DELAY_US 1

	#define PWRER_RETRIES 100
	#define PWRER_DELAY_US 1

	#define SYSCISR_RETRIES 1000
	#define SYSCISR_DELAY_US 1

	#define RCAR_PD_ALWAYS_ON 32 /* Always-on power area */

	static void __iomem *rcar_sysc_base;
	static DEFINE_SPINLOCK(rcar_sysc_lock); /* SMP CPUs + I/O devices */

	static int rcar_sysc_pwr_on_off(const struct rcar_sysc_ch *sysc_ch, bool on)
	{
	unsigned int sr_bit, reg_offs;
	int k;

	if (on) {
	sr_bit = SYSCSR_PONENB;
	reg_offs = PWRONCR_OFFS;
	} else {
	sr_bit = SYSCSR_POFFENB;
	reg_offs = PWROFFCR_OFFS;
	}

	/* Wait until SYSC is ready to accept a power request */
	for (k = 0; k < SYSCSR_RETRIES; k++) {
	if (ioread32(rcar_sysc_base + SYSCSR) & BIT(sr_bit))
	break;
	udelay(SYSCSR_DELAY_US);
	}

	if (k == SYSCSR_RETRIES)
	return -EAGAIN;

	/* Submit power shutoff or power resume request */
	iowrite32(BIT(sysc_ch->chan_bit),
	rcar_sysc_base + sysc_ch->chan_offs + reg_offs);

	return 0;
	}

	static int rcar_sysc_power(const struct rcar_sysc_ch *sysc_ch, bool on)
	{
	unsigned int isr_mask = BIT(sysc_ch->isr_bit);
	unsigned int chan_mask = BIT(sysc_ch->chan_bit);
	unsigned int status;
	unsigned long flags;
	int ret = 0;
	int k;

	spin_lock_irqsave(&rcar_sysc_lock, flags);

	iowrite32(isr_mask, rcar_sysc_base + SYSCISCR);

	/* Submit power shutoff or resume request until it was accepted */
	for (k = 0; k < PWRER_RETRIES; k++) {
	ret = rcar_sysc_pwr_on_off(sysc_ch, on);
	if (ret)
	goto out;

	status = ioread32(rcar_sysc_base +
	sysc_ch->chan_offs + PWRER_OFFS);
	if (!(status & chan_mask))
	break;

	udelay(PWRER_DELAY_US);
	}

	if (k == PWRER_RETRIES) {
	ret = -EIO;
	goto out;
	}

	/* Wait until the power shutoff or resume request has completed * */
	for (k = 0; k < SYSCISR_RETRIES; k++) {
	if (ioread32(rcar_sysc_base + SYSCISR) & isr_mask)
	break;
	udelay(SYSCISR_DELAY_US);
	}

	if (k == SYSCISR_RETRIES)
	ret = -EIO;

	iowrite32(isr_mask, rcar_sysc_base + SYSCISCR);

	out:
	spin_unlock_irqrestore(&rcar_sysc_lock, flags);

	pr_debug("sysc power %s domain %d: %08x -> %d\n", on ? "on" : "off",
	sysc_ch->isr_bit, ioread32(rcar_sysc_base + SYSCISR), ret);
	return ret;
	}

	int rcar_sysc_power_down(const struct rcar_sysc_ch *sysc_ch)
	{
	return rcar_sysc_power(sysc_ch, false);
	}

	int rcar_sysc_power_up(const struct rcar_sysc_ch *sysc_ch)
	{
	return rcar_sysc_power(sysc_ch, true);
	}

	static bool rcar_sysc_power_is_off(const struct rcar_sysc_ch *sysc_ch)
	{
	unsigned int st;

	st = ioread32(rcar_sysc_base + sysc_ch->chan_offs + PWRSR_OFFS);
	if (st & BIT(sysc_ch->chan_bit))
	return true;

	return false;
	}

	struct rcar_sysc_pd {
	struct generic_pm_domain genpd;
	struct rcar_sysc_ch ch;
	unsigned int flags;
	char name[0];
	};

	static inline struct rcar_sysc_pd to_rcar_pd(struct generic_pm_domain d)
	{
	return container_of(d, struct rcar_sysc_pd, genpd);
	}

	static int rcar_sysc_pd_power_off(struct generic_pm_domain *genpd)
	{
	struct rcar_sysc_pd *pd = to_rcar_pd(genpd);

	pr_debug("%s: %s\n", __func__, genpd->name);
	return rcar_sysc_power_down(&pd->ch);
	}

	static int rcar_sysc_pd_power_on(struct generic_pm_domain *genpd)
	{
	struct rcar_sysc_pd *pd = to_rcar_pd(genpd);

	pr_debug("%s: %s\n", __func__, genpd->name);
	return rcar_sysc_power_up(&pd->ch);
	}

	static bool has_cpg_mstp;

	static void __init rcar_sysc_pd_setup(struct rcar_sysc_pd *pd)
	{
	struct generic_pm_domain *genpd = &pd->genpd;
	const char *name = pd->genpd.name;
	struct dev_power_governor *gov = &simple_qos_governor;

	if (pd->flags & PD_CPU) {
	/*
	* This domain contains a CPU core and therefore it should
	* only be turned off if the CPU is not in use.
	*/
	pr_debug("PM domain %s contains %s\n", name, "CPU");
	genpd->flags \|= GENPD_FLAG_ALWAYS_ON;
	} else if (pd->flags & PD_SCU) {
	/*
	* This domain contains an SCU and cache-controller, and
	* therefore it should only be turned off if the CPU cores are
	* not in use.
	*/
	pr_debug("PM domain %s contains %s\n", name, "SCU");
	genpd->flags \|= GENPD_FLAG_ALWAYS_ON;
	} else if (pd->flags & PD_NO_CR) {
	/*
	* This domain cannot be turned off.
	*/
	genpd->flags \|= GENPD_FLAG_ALWAYS_ON;
	}

	if (!(pd->flags & (PD_CPU \| PD_SCU))) {
	/* Enable Clock Domain for I/O devices */
	genpd->flags \|= GENPD_FLAG_PM_CLK;
	if (has_cpg_mstp) {
	genpd->attach_dev = cpg_mstp_attach_dev;
	genpd->detach_dev = cpg_mstp_detach_dev;
	} else {
	genpd->attach_dev = cpg_mssr_attach_dev;
	genpd->detach_dev = cpg_mssr_detach_dev;
	}
	}

	genpd->power_off = rcar_sysc_pd_power_off;
	genpd->power_on = rcar_sysc_pd_power_on;

	if (pd->flags & (PD_CPU \| PD_NO_CR)) {
	/* Skip CPUs (handled by SMP code) and areas without control */
	pr_debug("%s: Not touching %s\n", __func__, genpd->name);
	goto finalize;
	}

	if (!rcar_sysc_power_is_off(&pd->ch)) {
	pr_debug("%s: %s is already powered\n", __func__, genpd->name);
	goto finalize;
	}

	rcar_sysc_power_up(&pd->ch);

	finalize:
	pm_genpd_init(genpd, gov, false);
	}

	static const struct of_device_id rcar_sysc_matches[] = {
	#ifdef CONFIG_SYSC_R8A7743
	{ .compatible = "renesas,r8a7743-sysc", .data = &r8a7743_sysc_info },
	#endif
	#ifdef CONFIG_SYSC_R8A7745
	{ .compatible = "renesas,r8a7745-sysc", .data = &r8a7745_sysc_info },
	#endif
	#ifdef CONFIG_SYSC_R8A7779
	{ .compatible = "renesas,r8a7779-sysc", .data = &r8a7779_sysc_info },
	#endif
	#ifdef CONFIG_SYSC_R8A7790
	{ .compatible = "renesas,r8a7790-sysc", .data = &r8a7790_sysc_info },
	#endif
	#ifdef CONFIG_SYSC_R8A7791
	{ .compatible = "renesas,r8a7791-sysc", .data = &r8a7791_sysc_info },
	/* R-Car M2-N is identical to R-Car M2-W w.r.t. power domains. */
	{ .compatible = "renesas,r8a7793-sysc", .data = &r8a7791_sysc_info },
	#endif
	#ifdef CONFIG_SYSC_R8A7792
	{ .compatible = "renesas,r8a7792-sysc", .data = &r8a7792_sysc_info },
	#endif
	#ifdef CONFIG_SYSC_R8A7794
	{ .compatible = "renesas,r8a7794-sysc", .data = &r8a7794_sysc_info },
	#endif
	#ifdef CONFIG_SYSC_R8A7795
	{ .compatible = "renesas,r8a7795-sysc", .data = &r8a7795_sysc_info },
	#endif
	#ifdef CONFIG_SYSC_R8A7796
	{ .compatible = "renesas,r8a7796-sysc", .data = &r8a7796_sysc_info },
	#endif
	#ifdef CONFIG_SYSC_R8A77995
	{ .compatible = "renesas,r8a77995-sysc", .data = &r8a77995_sysc_info },
	#endif
	{ /* sentinel */ }
	};

	struct rcar_pm_domains {
	struct genpd_onecell_data onecell_data;
	struct generic_pm_domain *domains[RCAR_PD_ALWAYS_ON + 1];
	};

	static int __init rcar_sysc_pd_init(void)
	{
	const struct rcar_sysc_info *info;
	const struct of_device_id *match;
	struct rcar_pm_domains *domains;
	struct device_node *np;
	u32 syscier, syscimr;
	void __iomem *base;
	unsigned int i;
	int error;

	if (rcar_sysc_base)
	return 0;

	np = of_find_matching_node_and_match(NULL, rcar_sysc_matches, &match);
	if (!np)
	return -ENODEV;

	info = match->data;

	if (info->init) {
	error = info->init();
	if (error)
	return error;
	}

	has_cpg_mstp = of_find_compatible_node(NULL, NULL,
	"renesas,cpg-mstp-clocks");

	base = of_iomap(np, 0);
	if (!base) {
	pr_warn("%pOF: Cannot map regs\n", np);
	error = -ENOMEM;
	goto out_put;
	}

	rcar_sysc_base = base;

	domains = kzalloc(sizeof(*domains), GFP_KERNEL);
	if (!domains) {
	error = -ENOMEM;
	goto out_put;
	}

	domains->onecell_data.domains = domains->domains;
	domains->onecell_data.num_domains = ARRAY_SIZE(domains->domains);

	for (i = 0, syscier = 0; i < info->num_areas; i++)
	syscier \|= BIT(info->areas[i].isr_bit);

	/*
	* Mask all interrupt sources to prevent the CPU from receiving them.
	* Make sure not to clear reserved bits that were set before.
	*/
	syscimr = ioread32(base + SYSCIMR);
	syscimr \|= syscier;
	pr_debug("%pOF: syscimr = 0x%08x\n", np, syscimr);
	iowrite32(syscimr, base + SYSCIMR);

	/*
	* SYSC needs all interrupt sources enabled to control power.
	*/
	pr_debug("%pOF: syscier = 0x%08x\n", np, syscier);
	iowrite32(syscier, base + SYSCIER);

	for (i = 0; i < info->num_areas; i++) {
	const struct rcar_sysc_area *area = &info->areas[i];
	struct rcar_sysc_pd *pd;

	if (!area->name) {
	/* Skip NULLified area */
	continue;
	}

	pd = kzalloc(sizeof(*pd) + strlen(area->name) + 1, GFP_KERNEL);
	if (!pd) {
	error = -ENOMEM;
	goto out_put;
	}

	strcpy(pd->name, area->name);
	pd->genpd.name = pd->name;
	pd->ch.chan_offs = area->chan_offs;
	pd->ch.chan_bit = area->chan_bit;
	pd->ch.isr_bit = area->isr_bit;
	pd->flags = area->flags;

	rcar_sysc_pd_setup(pd);
	if (area->parent >= 0)
	pm_genpd_add_subdomain(domains->domains[area->parent],
	&pd->genpd);

	domains->domains[area->isr_bit] = &pd->genpd;
	}

	error = of_genpd_add_provider_onecell(np, &domains->onecell_data);

	out_put:
	of_node_put(np);
	return error;
	}
	early_initcall(rcar_sysc_pd_init);

	void __init rcar_sysc_nullify(struct rcar_sysc_area *areas,
	unsigned int num_areas, u8 id)
	{
	unsigned int i;

	for (i = 0; i < num_areas; i++)
	if (areas[i].isr_bit == id) {
	areas[i].name = NULL;
	return;
	}
	}

	void __init rcar_sysc_init(phys_addr_t base, u32 syscier)
	{
	u32 syscimr;

	if (!rcar_sysc_pd_init())
	return;

	rcar_sysc_base = ioremap_nocache(base, PAGE_SIZE);

	/*
	* Mask all interrupt sources to prevent the CPU from receiving them.
	* Make sure not to clear reserved bits that were set before.
	*/
	syscimr = ioread32(rcar_sysc_base + SYSCIMR);
	syscimr \|= syscier;
	pr_debug("%s: syscimr = 0x%08x\n", __func__, syscimr);
	iowrite32(syscimr, rcar_sysc_base + SYSCIMR);

	/*
	* SYSC needs all interrupt sources enabled to control power.
	*/
	pr_debug("%s: syscier = 0x%08x\n", __func__, syscier);
	iowrite32(syscier, rcar_sysc_base + SYSCIER);
	}