/* * 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 * * 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/console.h> #include <linux/delay.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/pm.h> #include <linux/pm_clock.h> #include <linux/slab.h> #include <asm/io.h> #include "pm-rmobile.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 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; if (rmobile_pd->bit_shift == ~0) return -EBUSY; mask = BIT(rmobile_pd->bit_shift); if (rmobile_pd->suspend) { int ret = rmobile_pd->suspend(); if (ret) return ret; } if (__raw_readl(rmobile_pd->base + PSTR) & mask) { unsigned int retry_count; __raw_writel(mask, rmobile_pd->base + SPDCR); for (retry_count = PSTR_RETRIES; retry_count; retry_count--) { if (!(__raw_readl(rmobile_pd->base + SPDCR) & mask)) break; cpu_relax(); } } if (!rmobile_pd->no_debug) pr_debug("%s: Power off, 0x%08x -> PSTR = 0x%08x\n", genpd->name, mask, __raw_readl(rmobile_pd->base + PSTR)); return 0; } static int __rmobile_pd_power_up(struct rmobile_pm_domain *rmobile_pd, bool do_resume) { unsigned int mask; unsigned int retry_count; int ret = 0; if (rmobile_pd->bit_shift == ~0) return 0; mask = BIT(rmobile_pd->bit_shift); if (__raw_readl(rmobile_pd->base + PSTR) & mask) goto out; __raw_writel(mask, rmobile_pd->base + SWUCR); for (retry_count = 2 * PSTR_RETRIES; retry_count; retry_count--) { if (!(__raw_readl(rmobile_pd->base + SWUCR) & mask)) break; if (retry_count > PSTR_RETRIES) udelay(PSTR_DELAY_US); else cpu_relax(); } if (!retry_count) ret = -EIO; if (!rmobile_pd->no_debug) pr_debug("%s: Power on, 0x%08x -> PSTR = 0x%08x\n", rmobile_pd->genpd.name, mask, __raw_readl(rmobile_pd->base + PSTR)); out: if (ret == 0 && rmobile_pd->resume && do_resume) rmobile_pd->resume(); return ret; } static int rmobile_pd_power_up(struct generic_pm_domain *genpd) { return __rmobile_pd_power_up(to_rmobile_pd(genpd), true); } 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->power_off = rmobile_pd_power_down; genpd->power_on = rmobile_pd_power_up; genpd->attach_dev = cpg_mstp_attach_dev; genpd->detach_dev = cpg_mstp_detach_dev; __rmobile_pd_power_up(rmobile_pd, false); 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 %s type %d for %pOF\n", pd->name, 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_node_by_type(np, "cpu") 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, (enum pd_types)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: 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) { 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; } } put_special_pds(); return ret; } core_initcall(rmobile_init_pm_domains);