// SPDX-License-Identifier: GPL-2.0
/*
* R-Car SYSC Power management support
*
* Copyright (C) 2014 Magnus Damm
* Copyright (C) 2015-2017 Glider bvba
*/
#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/iopoll.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_TIMEOUT 1000
#define SYSCSR_DELAY_US 1
#define PWRER_RETRIES 1000
#define PWRER_DELAY_US 1
#define SYSCISR_TIMEOUT 1000
#define SYSCISR_DELAY_US 1
#define RCAR_PD_ALWAYS_ON 32 /* Always-on power area */
struct rcar_sysc_pd {
struct generic_pm_domain genpd;
u16 chan_offs;
u8 chan_bit;
u8 isr_bit;
unsigned int flags;
char name[];
};
static void __iomem *rcar_sysc_base;
static DEFINE_SPINLOCK(rcar_sysc_lock); /* SMP CPUs + I/O devices */
static u32 rcar_sysc_extmask_offs, rcar_sysc_extmask_val;
static int rcar_sysc_pwr_on_off(const struct rcar_sysc_pd *pd, bool on)
{
unsigned int sr_bit, reg_offs;
u32 val;
int ret;
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 */
ret = readl_poll_timeout_atomic(rcar_sysc_base + SYSCSR, val,
val & BIT(sr_bit), SYSCSR_DELAY_US,
SYSCSR_TIMEOUT);
if (ret)
return -EAGAIN;
/* Power-off delay quirk */
if (!on && (pd->flags & PD_OFF_DELAY))
udelay(1);
/* Submit power shutoff or power resume request */
iowrite32(BIT(pd->chan_bit), rcar_sysc_base + pd->chan_offs + reg_offs);
return 0;
}
static int rcar_sysc_power(const struct rcar_sysc_pd *pd, bool on)
{
unsigned int isr_mask = BIT(pd->isr_bit);
unsigned int chan_mask = BIT(pd->chan_bit);
unsigned int status, k;
unsigned long flags;
int ret;
spin_lock_irqsave(&rcar_sysc_lock, flags);
/*
* Mask external power requests for CPU or 3DG domains
*/
if (rcar_sysc_extmask_val) {
iowrite32(rcar_sysc_extmask_val,
rcar_sysc_base + rcar_sysc_extmask_offs);
}
/*
* The interrupt source needs to be enabled, but masked, to prevent the
* CPU from receiving it.
*/
iowrite32(ioread32(rcar_sysc_base + SYSCIMR) | isr_mask,
rcar_sysc_base + SYSCIMR);
iowrite32(ioread32(rcar_sysc_base + SYSCIER) | isr_mask,
rcar_sysc_base + SYSCIER);
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(pd, on);
if (ret)
goto out;
status = ioread32(rcar_sysc_base + pd->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 * */
ret = readl_poll_timeout_atomic(rcar_sysc_base + SYSCISR, status,
status & isr_mask, SYSCISR_DELAY_US,
SYSCISR_TIMEOUT);
if (ret)
ret = -EIO;
iowrite32(isr_mask, rcar_sysc_base + SYSCISCR);
out:
if (rcar_sysc_extmask_val)
iowrite32(0, rcar_sysc_base + rcar_sysc_extmask_offs);
spin_unlock_irqrestore(&rcar_sysc_lock, flags);
pr_debug("sysc power %s domain %d: %08x -> %d\n", on ? "on" : "off",
pd->isr_bit, ioread32(rcar_sysc_base + SYSCISR), ret);
return ret;
}
static bool rcar_sysc_power_is_off(const struct rcar_sysc_pd *pd)
{
unsigned int st;
st = ioread32(rcar_sysc_base + pd->chan_offs + PWRSR_OFFS);
if (st & BIT(pd->chan_bit))
return true;
return false;
}
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(pd, false);
}
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(pd, true);
}
static bool has_cpg_mstp;
static int __init rcar_sysc_pd_setup(struct rcar_sysc_pd *pd)
{
struct generic_pm_domain *genpd = &pd->genpd;
const char *name = pd->genpd.name;
int error;
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 | GENPD_FLAG_ACTIVE_WAKEUP;
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)) {
pr_debug("%s: %s is already powered\n", __func__, genpd->name);
goto finalize;
}
rcar_sysc_power(pd, true);
finalize:
error = pm_genpd_init(genpd, &simple_qos_governor, false);
if (error)
pr_err("Failed to init PM domain %s: %d\n", name, error);
return error;
}
static const struct of_device_id rcar_sysc_matches[] __initconst = {
#ifdef CONFIG_SYSC_R8A7742
{ .compatible = "renesas,r8a7742-sysc", .data = &r8a7742_sysc_info },
#endif
#ifdef CONFIG_SYSC_R8A7743
{ .compatible = "renesas,r8a7743-sysc", .data = &r8a7743_sysc_info },
/* RZ/G1N is identical to RZ/G2M w.r.t. power domains. */
{ .compatible = "renesas,r8a7744-sysc", .data = &r8a7743_sysc_info },
#endif
#ifdef CONFIG_SYSC_R8A7745
{ .compatible = "renesas,r8a7745-sysc", .data = &r8a7745_sysc_info },
#endif
#ifdef CONFIG_SYSC_R8A77470
{ .compatible = "renesas,r8a77470-sysc", .data = &r8a77470_sysc_info },
#endif
#ifdef CONFIG_SYSC_R8A774A1
{ .compatible = "renesas,r8a774a1-sysc", .data = &r8a774a1_sysc_info },
#endif
#ifdef CONFIG_SYSC_R8A774B1
{ .compatible = "renesas,r8a774b1-sysc", .data = &r8a774b1_sysc_info },
#endif
#ifdef CONFIG_SYSC_R8A774C0
{ .compatible = "renesas,r8a774c0-sysc", .data = &r8a774c0_sysc_info },
#endif
#ifdef CONFIG_SYSC_R8A774E1
{ .compatible = "renesas,r8a774e1-sysc", .data = &r8a774e1_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_R8A77960
{ .compatible = "renesas,r8a7796-sysc", .data = &r8a77960_sysc_info },
#endif
#ifdef CONFIG_SYSC_R8A77961
{ .compatible = "renesas,r8a77961-sysc", .data = &r8a77961_sysc_info },
#endif
#ifdef CONFIG_SYSC_R8A77965
{ .compatible = "renesas,r8a77965-sysc", .data = &r8a77965_sysc_info },
#endif
#ifdef CONFIG_SYSC_R8A77970
{ .compatible = "renesas,r8a77970-sysc", .data = &r8a77970_sysc_info },
#endif
#ifdef CONFIG_SYSC_R8A77980
{ .compatible = "renesas,r8a77980-sysc", .data = &r8a77980_sysc_info },
#endif
#ifdef CONFIG_SYSC_R8A77990
{ .compatible = "renesas,r8a77990-sysc", .data = &r8a77990_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 struct genpd_onecell_data *rcar_sysc_onecell_data;
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;
void __iomem *base;
unsigned int i;
int error;
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)
goto out_put;
}
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;
/* Optional External Request Mask Register */
rcar_sysc_extmask_offs = info->extmask_offs;
rcar_sysc_extmask_val = info->extmask_val;
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);
rcar_sysc_onecell_data = &domains->onecell_data;
for (i = 0; i < info->num_areas; i++) {
const struct rcar_sysc_area *area = &info->areas[i];
struct rcar_sysc_pd *pd;
size_t n;
if (!area->name) {
/* Skip NULLified area */
continue;
}
n = strlen(area->name) + 1;
pd = kzalloc(sizeof(*pd) + n, GFP_KERNEL);
if (!pd) {
error = -ENOMEM;
goto out_put;
}
memcpy(pd->name, area->name, n);
pd->genpd.name = pd->name;
pd->chan_offs = area->chan_offs;
pd->chan_bit = area->chan_bit;
pd->isr_bit = area->isr_bit;
pd->flags = area->flags;
error = rcar_sysc_pd_setup(pd);
if (error)
goto out_put;
domains->domains[area->isr_bit] = &pd->genpd;
if (area->parent < 0)
continue;
error = pm_genpd_add_subdomain(domains->domains[area->parent],
&pd->genpd);
if (error) {
pr_warn("Failed to add PM subdomain %s to parent %u\n",
area->name, area->parent);
goto out_put;
}
}
error = of_genpd_add_provider_onecell(np, &domains->onecell_data);
if (!error)
fwnode_dev_initialized(of_fwnode_handle(np), true);
out_put:
of_node_put(np);
return error;
}
early_initcall(rcar_sysc_pd_init);
#ifdef CONFIG_ARCH_R8A7779
static int rcar_sysc_power_cpu(unsigned int idx, bool on)
{
struct generic_pm_domain *genpd;
struct rcar_sysc_pd *pd;
unsigned int i;
if (!rcar_sysc_onecell_data)
return -ENODEV;
for (i = 0; i < rcar_sysc_onecell_data->num_domains; i++) {
genpd = rcar_sysc_onecell_data->domains[i];
if (!genpd)
continue;
pd = to_rcar_pd(genpd);
if (!(pd->flags & PD_CPU) || pd->chan_bit != idx)
continue;
return rcar_sysc_power(pd, on);
}
return -ENOENT;
}
int rcar_sysc_power_down_cpu(unsigned int cpu)
{
return rcar_sysc_power_cpu(cpu, false);
}
int rcar_sysc_power_up_cpu(unsigned int cpu)
{
return rcar_sysc_power_cpu(cpu, true);
}
#endif /* CONFIG_ARCH_R8A7779 */
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