summaryrefslogtreecommitdiffstats
path: root/drivers/pmdomain/renesas/rmobile-sysc.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/pmdomain/renesas/rmobile-sysc.c')
-rw-r--r--drivers/pmdomain/renesas/rmobile-sysc.c343
1 files changed, 343 insertions, 0 deletions
diff --git a/drivers/pmdomain/renesas/rmobile-sysc.c b/drivers/pmdomain/renesas/rmobile-sysc.c
new file mode 100644
index 0000000000..912daadaa1
--- /dev/null
+++ b/drivers/pmdomain/renesas/rmobile-sysc.c
@@ -0,0 +1,343 @@
+// 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, (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:
+ 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);