drivers/pmdomain/renesas/rmobile-sysc.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * rmobile power management support
  *
  * Copyright (C) 2012  Renesas Solutions Corp.
  * Copyright (C) 2012  Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
  * Copyright (C) 2014  Glider bvba
  *
  * based on pm-sh7372.c
  *  Copyright (C) 2011 Magnus Damm
  */
 #include <linux/clk/renesas.h>
 #include <linux/console.h>
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/pm.h>
 #include <linux/pm_clock.h>
 #include <linux/pm_domain.h>
 #include <linux/slab.h>

 /* SYSC */
 #define SPDCR		0x08	/* SYS Power Down Control Register */
 #define SWUCR		0x14	/* SYS Wakeup Control Register */
 #define PSTR		0x80	/* Power Status Register */

 #define PSTR_RETRIES	100
 #define PSTR_DELAY_US	10

 struct rmobile_pm_domain {
 	struct generic_pm_domain genpd;
 	struct dev_power_governor *gov;
 	int (*suspend)(void);
 	void __iomem *base;
 	unsigned int bit_shift;
 };

 static inline
 struct rmobile_pm_domain *to_rmobile_pd(struct generic_pm_domain *d)
 {
 	return container_of(d, struct rmobile_pm_domain, genpd);
 }

 static int rmobile_pd_power_down(struct generic_pm_domain *genpd)
 {
 	struct rmobile_pm_domain *rmobile_pd = to_rmobile_pd(genpd);
 	unsigned int mask = BIT(rmobile_pd->bit_shift);
 	u32 val;

 	if (rmobile_pd->suspend) {
 		int ret = rmobile_pd->suspend();

 		if (ret)
 			return ret;
 	}

 	if (readl(rmobile_pd->base + PSTR) & mask) {
 		writel(mask, rmobile_pd->base + SPDCR);

 		readl_poll_timeout_atomic(rmobile_pd->base + SPDCR, val,
 					  !(val & mask), 0, PSTR_RETRIES);
 	}

 	pr_debug("%s: Power off, 0x%08x -> PSTR = 0x%08x\n", genpd->name, mask,
 		 readl(rmobile_pd->base + PSTR));

 	return 0;
 }

 static int __rmobile_pd_power_up(struct rmobile_pm_domain *rmobile_pd)
 {
 	unsigned int val, mask = BIT(rmobile_pd->bit_shift);
 	int ret = 0;

 	if (readl(rmobile_pd->base + PSTR) & mask)
 		return ret;

 	writel(mask, rmobile_pd->base + SWUCR);

 	ret = readl_poll_timeout_atomic(rmobile_pd->base + SWUCR, val,
 					(val & mask), PSTR_DELAY_US,
 					PSTR_RETRIES * PSTR_DELAY_US);

 	pr_debug("%s: Power on, 0x%08x -> PSTR = 0x%08x\n",
 		 rmobile_pd->genpd.name, mask,
 		 readl(rmobile_pd->base + PSTR));

 	return ret;
 }

 static int rmobile_pd_power_up(struct generic_pm_domain *genpd)
 {
 	return __rmobile_pd_power_up(to_rmobile_pd(genpd));
 }

 static void rmobile_init_pm_domain(struct rmobile_pm_domain *rmobile_pd)
 {
 	struct generic_pm_domain *genpd = &rmobile_pd->genpd;
 	struct dev_power_governor *gov = rmobile_pd->gov;

 	genpd->flags |= GENPD_FLAG_PM_CLK | GENPD_FLAG_ACTIVE_WAKEUP;
 	genpd->attach_dev = cpg_mstp_attach_dev;
 	genpd->detach_dev = cpg_mstp_detach_dev;

 	if (!(genpd->flags & GENPD_FLAG_ALWAYS_ON)) {
 		genpd->power_off = rmobile_pd_power_down;
 		genpd->power_on = rmobile_pd_power_up;
 		__rmobile_pd_power_up(rmobile_pd);
 	}

 	pm_genpd_init(genpd, gov ? : &simple_qos_governor, false);
 }

 static int rmobile_pd_suspend_console(void)
 {
 	/*
 	 * Serial consoles make use of SCIF hardware located in this domain,
 	 * hence keep the power domain on if "no_console_suspend" is set.
 	 */
 	return console_suspend_enabled ? 0 : -EBUSY;
 }

 enum pd_types {
 	PD_NORMAL,
 	PD_CPU,
 	PD_CONSOLE,
 	PD_DEBUG,
 	PD_MEMCTL,
 };

 #define MAX_NUM_SPECIAL_PDS	16

 static struct special_pd {
 	struct device_node *pd;
 	enum pd_types type;
 } special_pds[MAX_NUM_SPECIAL_PDS] __initdata;

 static unsigned int num_special_pds __initdata;

 static const struct of_device_id special_ids[] __initconst = {
 	{ .compatible = "arm,coresight-etm3x", .data = (void *)PD_DEBUG },
 	{ .compatible = "renesas,dbsc-r8a73a4", .data = (void *)PD_MEMCTL, },
 	{ .compatible = "renesas,dbsc3-r8a7740", .data = (void *)PD_MEMCTL, },
 	{ .compatible = "renesas,sbsc-sh73a0", .data = (void *)PD_MEMCTL, },
 	{ /* sentinel */ },
 };

 static void __init add_special_pd(struct device_node *np, enum pd_types type)
 {
 	unsigned int i;
 	struct device_node *pd;

 	pd = of_parse_phandle(np, "power-domains", 0);
 	if (!pd)
 		return;

 	for (i = 0; i < num_special_pds; i++)
 		if (pd == special_pds[i].pd && type == special_pds[i].type) {
 			of_node_put(pd);
 			return;
 		}

 	if (num_special_pds == ARRAY_SIZE(special_pds)) {
 		pr_warn("Too many special PM domains\n");
 		of_node_put(pd);
 		return;
 	}

 	pr_debug("Special PM domain %pOFn type %d for %pOF\n", pd, type, np);

 	special_pds[num_special_pds].pd = pd;
 	special_pds[num_special_pds].type = type;
 	num_special_pds++;
 }

 static void __init get_special_pds(void)
 {
 	struct device_node *np;
 	const struct of_device_id *id;

 	/* PM domains containing CPUs */
 	for_each_of_cpu_node(np)
 		add_special_pd(np, PD_CPU);

 	/* PM domain containing console */
 	if (of_stdout)
 		add_special_pd(of_stdout, PD_CONSOLE);

 	/* PM domains containing other special devices */
 	for_each_matching_node_and_match(np, special_ids, &id)
 		add_special_pd(np, (uintptr_t)id->data);
 }

 static void __init put_special_pds(void)
 {
 	unsigned int i;

 	for (i = 0; i < num_special_pds; i++)
 		of_node_put(special_pds[i].pd);
 }

 static enum pd_types __init pd_type(const struct device_node *pd)
 {
 	unsigned int i;

 	for (i = 0; i < num_special_pds; i++)
 		if (pd == special_pds[i].pd)
 			return special_pds[i].type;

 	return PD_NORMAL;
 }

 static void __init rmobile_setup_pm_domain(struct device_node *np,
 					   struct rmobile_pm_domain *pd)
 {
 	const char *name = pd->genpd.name;

 	switch (pd_type(np)) {
 	case PD_CPU:
 		/*
 		 * This domain contains the CPU core and therefore it should
 		 * only be turned off if the CPU is not in use.
 		 */
 		pr_debug("PM domain %s contains CPU\n", name);
 		pd->genpd.flags |= GENPD_FLAG_ALWAYS_ON;
 		break;

 	case PD_CONSOLE:
 		pr_debug("PM domain %s contains serial console\n", name);
 		pd->gov = &pm_domain_always_on_gov;
 		pd->suspend = rmobile_pd_suspend_console;
 		break;

 	case PD_DEBUG:
 		/*
 		 * This domain contains the Coresight-ETM hardware block and
 		 * therefore it should only be turned off if the debug module
 		 * is not in use.
 		 */
 		pr_debug("PM domain %s contains Coresight-ETM\n", name);
 		pd->genpd.flags |= GENPD_FLAG_ALWAYS_ON;
 		break;

 	case PD_MEMCTL:
 		/*
 		 * This domain contains a memory-controller and therefore it
 		 * should only be turned off if memory is not in use.
 		 */
 		pr_debug("PM domain %s contains MEMCTL\n", name);
 		pd->genpd.flags |= GENPD_FLAG_ALWAYS_ON;
 		break;

 	case PD_NORMAL:
 		if (pd->bit_shift == ~0) {
 			/* Top-level always-on domain */
 			pr_debug("PM domain %s is always-on domain\n", name);
 			pd->genpd.flags |= GENPD_FLAG_ALWAYS_ON;
 		}
 		break;
 	}

 	rmobile_init_pm_domain(pd);
 }

 static int __init rmobile_add_pm_domains(void __iomem *base,
 					 struct device_node *parent,
 					 struct generic_pm_domain *genpd_parent)
 {
 	struct device_node *np;

 	for_each_child_of_node(parent, np) {
 		struct rmobile_pm_domain *pd;
 		u32 idx = ~0;

 		if (of_property_read_u32(np, "reg", &idx)) {
 			/* always-on domain */
 		}

 		pd = kzalloc(sizeof(*pd), GFP_KERNEL);
 		if (!pd) {
 			of_node_put(np);
 			return -ENOMEM;
 		}

 		pd->genpd.name = np->name;
 		pd->base = base;
 		pd->bit_shift = idx;

 		rmobile_setup_pm_domain(np, pd);
 		if (genpd_parent)
 			pm_genpd_add_subdomain(genpd_parent, &pd->genpd);
 		of_genpd_add_provider_simple(np, &pd->genpd);

 		rmobile_add_pm_domains(base, np, &pd->genpd);
 	}
 	return 0;
 }

 static int __init rmobile_init_pm_domains(void)
 {
 	struct device_node *np, *pmd;
 	bool scanned = false;
 	void __iomem *base;
 	int ret = 0;

 	for_each_compatible_node(np, NULL, "renesas,sysc-rmobile") {
 		base = of_iomap(np, 0);
 		if (!base) {
 			pr_warn("%pOF cannot map reg 0\n", np);
 			continue;
 		}

 		pmd = of_get_child_by_name(np, "pm-domains");
 		if (!pmd) {
 			iounmap(base);
 			pr_warn("%pOF lacks pm-domains node\n", np);
 			continue;
 		}

 		if (!scanned) {
 			/* Find PM domains containing special blocks */
 			get_special_pds();
 			scanned = true;
 		}

 		ret = rmobile_add_pm_domains(base, pmd, NULL);
 		of_node_put(pmd);
 		if (ret) {
 			of_node_put(np);
 			break;
 		}

 		fwnode_dev_initialized(of_fwnode_handle(np), true);
 	}

 	put_special_pds();

 	return ret;
 }

 core_initcall(rmobile_init_pm_domains);
	// SPDX-License-Identifier: GPL-2.0
	/*
	* rmobile power management support
	*
	* Copyright (C) 2012 Renesas Solutions Corp.
	* Copyright (C) 2012 Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
	* Copyright (C) 2014 Glider bvba
	*
	* based on pm-sh7372.c
	* Copyright (C) 2011 Magnus Damm
	*/
	#include <linux/clk/renesas.h>
	#include <linux/console.h>
	#include <linux/delay.h>
	#include <linux/io.h>
	#include <linux/iopoll.h>
	#include <linux/of.h>
	#include <linux/of_address.h>
	#include <linux/pm.h>
	#include <linux/pm_clock.h>
	#include <linux/pm_domain.h>
	#include <linux/slab.h>

	/* SYSC */
	#define SPDCR 0x08 /* SYS Power Down Control Register */
	#define SWUCR 0x14 /* SYS Wakeup Control Register */
	#define PSTR 0x80 /* Power Status Register */

	#define PSTR_RETRIES 100
	#define PSTR_DELAY_US 10

	struct rmobile_pm_domain {
	struct generic_pm_domain genpd;
	struct dev_power_governor *gov;
	int (*suspend)(void);
	void __iomem *base;
	unsigned int bit_shift;
	};

	static inline
	struct rmobile_pm_domain to_rmobile_pd(struct generic_pm_domain d)
	{
	return container_of(d, struct rmobile_pm_domain, genpd);
	}

	static int rmobile_pd_power_down(struct generic_pm_domain *genpd)
	{
	struct rmobile_pm_domain *rmobile_pd = to_rmobile_pd(genpd);
	unsigned int mask = BIT(rmobile_pd->bit_shift);
	u32 val;

	if (rmobile_pd->suspend) {
	int ret = rmobile_pd->suspend();

	if (ret)
	return ret;
	}

	if (readl(rmobile_pd->base + PSTR) & mask) {
	writel(mask, rmobile_pd->base + SPDCR);

	readl_poll_timeout_atomic(rmobile_pd->base + SPDCR, val,
	!(val & mask), 0, PSTR_RETRIES);
	}

	pr_debug("%s: Power off, 0x%08x -> PSTR = 0x%08x\n", genpd->name, mask,
	readl(rmobile_pd->base + PSTR));

	return 0;
	}

	static int __rmobile_pd_power_up(struct rmobile_pm_domain *rmobile_pd)
	{
	unsigned int val, mask = BIT(rmobile_pd->bit_shift);
	int ret = 0;

	if (readl(rmobile_pd->base + PSTR) & mask)
	return ret;

	writel(mask, rmobile_pd->base + SWUCR);

	ret = readl_poll_timeout_atomic(rmobile_pd->base + SWUCR, val,
	(val & mask), PSTR_DELAY_US,
	PSTR_RETRIES * PSTR_DELAY_US);

	pr_debug("%s: Power on, 0x%08x -> PSTR = 0x%08x\n",
	rmobile_pd->genpd.name, mask,
	readl(rmobile_pd->base + PSTR));

	return ret;
	}

	static int rmobile_pd_power_up(struct generic_pm_domain *genpd)
	{
	return __rmobile_pd_power_up(to_rmobile_pd(genpd));
	}

	static void rmobile_init_pm_domain(struct rmobile_pm_domain *rmobile_pd)
	{
	struct generic_pm_domain *genpd = &rmobile_pd->genpd;
	struct dev_power_governor *gov = rmobile_pd->gov;

	genpd->flags \|= GENPD_FLAG_PM_CLK \| GENPD_FLAG_ACTIVE_WAKEUP;
	genpd->attach_dev = cpg_mstp_attach_dev;
	genpd->detach_dev = cpg_mstp_detach_dev;

	if (!(genpd->flags & GENPD_FLAG_ALWAYS_ON)) {
	genpd->power_off = rmobile_pd_power_down;
	genpd->power_on = rmobile_pd_power_up;
	__rmobile_pd_power_up(rmobile_pd);
	}

	pm_genpd_init(genpd, gov ? : &simple_qos_governor, false);
	}

	static int rmobile_pd_suspend_console(void)
	{
	/*
	* Serial consoles make use of SCIF hardware located in this domain,
	* hence keep the power domain on if "no_console_suspend" is set.
	*/
	return console_suspend_enabled ? 0 : -EBUSY;
	}

	enum pd_types {
	PD_NORMAL,
	PD_CPU,
	PD_CONSOLE,
	PD_DEBUG,
	PD_MEMCTL,
	};

	#define MAX_NUM_SPECIAL_PDS 16

	static struct special_pd {
	struct device_node *pd;
	enum pd_types type;
	} special_pds[MAX_NUM_SPECIAL_PDS] __initdata;

	static unsigned int num_special_pds __initdata;

	static const struct of_device_id special_ids[] __initconst = {
	{ .compatible = "arm,coresight-etm3x", .data = (void *)PD_DEBUG },
	{ .compatible = "renesas,dbsc-r8a73a4", .data = (void *)PD_MEMCTL, },
	{ .compatible = "renesas,dbsc3-r8a7740", .data = (void *)PD_MEMCTL, },
	{ .compatible = "renesas,sbsc-sh73a0", .data = (void *)PD_MEMCTL, },
	{ /* sentinel */ },
	};

	static void __init add_special_pd(struct device_node *np, enum pd_types type)
	{
	unsigned int i;
	struct device_node *pd;

	pd = of_parse_phandle(np, "power-domains", 0);
	if (!pd)
	return;

	for (i = 0; i < num_special_pds; i++)
	if (pd == special_pds[i].pd && type == special_pds[i].type) {
	of_node_put(pd);
	return;
	}

	if (num_special_pds == ARRAY_SIZE(special_pds)) {
	pr_warn("Too many special PM domains\n");
	of_node_put(pd);
	return;
	}

	pr_debug("Special PM domain %pOFn type %d for %pOF\n", pd, type, np);

	special_pds[num_special_pds].pd = pd;
	special_pds[num_special_pds].type = type;
	num_special_pds++;
	}

	static void __init get_special_pds(void)
	{
	struct device_node *np;
	const struct of_device_id *id;

	/* PM domains containing CPUs */
	for_each_of_cpu_node(np)
	add_special_pd(np, PD_CPU);

	/* PM domain containing console */
	if (of_stdout)
	add_special_pd(of_stdout, PD_CONSOLE);

	/* PM domains containing other special devices */
	for_each_matching_node_and_match(np, special_ids, &id)
	add_special_pd(np, (uintptr_t)id->data);
	}

	static void __init put_special_pds(void)
	{
	unsigned int i;

	for (i = 0; i < num_special_pds; i++)
	of_node_put(special_pds[i].pd);
	}

	static enum pd_types __init pd_type(const struct device_node *pd)
	{
	unsigned int i;

	for (i = 0; i < num_special_pds; i++)
	if (pd == special_pds[i].pd)
	return special_pds[i].type;

	return PD_NORMAL;
	}

	static void __init rmobile_setup_pm_domain(struct device_node *np,
	struct rmobile_pm_domain *pd)
	{
	const char *name = pd->genpd.name;

	switch (pd_type(np)) {
	case PD_CPU:
	/*
	* This domain contains the CPU core and therefore it should
	* only be turned off if the CPU is not in use.
	*/
	pr_debug("PM domain %s contains CPU\n", name);
	pd->genpd.flags \|= GENPD_FLAG_ALWAYS_ON;
	break;

	case PD_CONSOLE:
	pr_debug("PM domain %s contains serial console\n", name);
	pd->gov = &pm_domain_always_on_gov;
	pd->suspend = rmobile_pd_suspend_console;
	break;

	case PD_DEBUG:
	/*
	* This domain contains the Coresight-ETM hardware block and
	* therefore it should only be turned off if the debug module
	* is not in use.
	*/
	pr_debug("PM domain %s contains Coresight-ETM\n", name);
	pd->genpd.flags \|= GENPD_FLAG_ALWAYS_ON;
	break;

	case PD_MEMCTL:
	/*
	* This domain contains a memory-controller and therefore it
	* should only be turned off if memory is not in use.
	*/
	pr_debug("PM domain %s contains MEMCTL\n", name);
	pd->genpd.flags \|= GENPD_FLAG_ALWAYS_ON;
	break;

	case PD_NORMAL:
	if (pd->bit_shift == ~0) {
	/* Top-level always-on domain */
	pr_debug("PM domain %s is always-on domain\n", name);
	pd->genpd.flags \|= GENPD_FLAG_ALWAYS_ON;
	}
	break;
	}

	rmobile_init_pm_domain(pd);
	}

	static int __init rmobile_add_pm_domains(void __iomem *base,
	struct device_node *parent,
	struct generic_pm_domain *genpd_parent)
	{
	struct device_node *np;

	for_each_child_of_node(parent, np) {
	struct rmobile_pm_domain *pd;
	u32 idx = ~0;

	if (of_property_read_u32(np, "reg", &idx)) {
	/* always-on domain */
	}

	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
	if (!pd) {
	of_node_put(np);
	return -ENOMEM;
	}

	pd->genpd.name = np->name;
	pd->base = base;
	pd->bit_shift = idx;

	rmobile_setup_pm_domain(np, pd);
	if (genpd_parent)
	pm_genpd_add_subdomain(genpd_parent, &pd->genpd);
	of_genpd_add_provider_simple(np, &pd->genpd);

	rmobile_add_pm_domains(base, np, &pd->genpd);
	}
	return 0;
	}

	static int __init rmobile_init_pm_domains(void)
	{
	struct device_node np, pmd;
	bool scanned = false;
	void __iomem *base;
	int ret = 0;

	for_each_compatible_node(np, NULL, "renesas,sysc-rmobile") {
	base = of_iomap(np, 0);
	if (!base) {
	pr_warn("%pOF cannot map reg 0\n", np);
	continue;
	}

	pmd = of_get_child_by_name(np, "pm-domains");
	if (!pmd) {
	iounmap(base);
	pr_warn("%pOF lacks pm-domains node\n", np);
	continue;
	}

	if (!scanned) {
	/* Find PM domains containing special blocks */
	get_special_pds();
	scanned = true;
	}

	ret = rmobile_add_pm_domains(base, pmd, NULL);
	of_node_put(pmd);
	if (ret) {
	of_node_put(np);
	break;
	}

	fwnode_dev_initialized(of_fwnode_handle(np), true);
	}

	put_special_pds();

	return ret;
	}

	core_initcall(rmobile_init_pm_domains);