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Release 4.14 drivers/soc/renesas/rcar-sysc.c

/*
 * 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; }

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm7664.96%120.00%
Geert Uytterhoeven4135.04%480.00%
Total117100.00%5100.00%


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; }

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PersonTokensPropCommitsCommitProp
Magnus Damm17473.73%114.29%
Geert Uytterhoeven6226.27%685.71%
Total236100.00%7100.00%


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

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm1684.21%133.33%
Geert Uytterhoeven315.79%266.67%
Total19100.00%3100.00%


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

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm1684.21%133.33%
Geert Uytterhoeven315.79%266.67%
Total19100.00%3100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm4189.13%125.00%
Geert Uytterhoeven510.87%375.00%
Total46100.00%4100.00%

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); }

Contributors

PersonTokensPropCommitsCommitProp
Geert Uytterhoeven25100.00%1100.00%
Total25100.00%1100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Geert Uytterhoeven41100.00%1100.00%
Total41100.00%1100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Geert Uytterhoeven41100.00%1100.00%
Total41100.00%1100.00%

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); }

Contributors

PersonTokensPropCommitsCommitProp
Geert Uytterhoeven256100.00%3100.00%
Total256100.00%3100.00%

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; }

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PersonTokensPropCommitsCommitProp
Geert Uytterhoeven49199.39%583.33%
Rob Herring30.61%116.67%
Total494100.00%6100.00%

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; } }

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PersonTokensPropCommitsCommitProp
Geert Uytterhoeven58100.00%1100.00%
Total58100.00%1100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Geert Uytterhoeven82100.00%3100.00%
Total82100.00%3100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Geert Uytterhoeven138775.54%2578.12%
Magnus Damm39621.57%26.25%
Sergei Shtylyov492.67%39.38%
Rob Herring30.16%13.12%
Dan J Williams10.05%13.12%
Total1836100.00%32100.00%
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