[PATCH 3/3] ARM: shmobile: R-Mobile: Add DT support for PM domains
Simon Horman
horms+renesas at verge.net.au
Fri Jan 16 16:59:26 PST 2015
From: Geert Uytterhoeven <geert+renesas at glider.be>
Populate the PM domains from DT, and provide support to hook up devices
to their respective PM domain.
The always-on power area (e.g. C5 on r8a7740) is created as a PM domain
without software control, to allow Run-Time management of module clocks
for hardware blocks inside this area.
Special cases like PM domains containing CPUs, the console device, or
Coresight-ETM, are handled by scanning the DT topology.
As long as the ARM debug/perf code doesn't use resource management with
runtime PM support, the power area containing Coresight-ETM (e.g. D4 on
r8a7740) must be kept powered to avoid a crash during resume from s2ram
(dbg_cpu_pm_notify() calls reset_ctrl_regs() unconditionally, causing an
undefined instruction oops).
Initialization is done from core_initcall(), as the
"renesas,intc-irqpin" driver uses postcore_initcall().
Signed-off-by: Geert Uytterhoeven <geert+renesas at glider.be>
Signed-off-by: Simon Horman <horms+renesas at verge.net.au>
---
arch/arm/mach-shmobile/Kconfig | 3 +-
arch/arm/mach-shmobile/pm-rmobile.c | 217 +++++++++++++++++++++++++++++++++++-
arch/arm/mach-shmobile/pm-rmobile.h | 2 +-
3 files changed, 218 insertions(+), 4 deletions(-)
diff --git a/arch/arm/mach-shmobile/Kconfig b/arch/arm/mach-shmobile/Kconfig
index d107b93..894c6876 100644
--- a/arch/arm/mach-shmobile/Kconfig
+++ b/arch/arm/mach-shmobile/Kconfig
@@ -7,6 +7,7 @@ config PM_RCAR
config PM_RMOBILE
bool
+ select PM_GENERIC_DOMAINS
config ARCH_RCAR_GEN1
bool
@@ -23,7 +24,7 @@ config ARCH_RCAR_GEN2
config ARCH_RMOBILE
bool
- select PM_RMOBILE if PM && !ARCH_SHMOBILE_MULTI
+ select PM_RMOBILE if PM
select SYS_SUPPORTS_SH_CMT
select SYS_SUPPORTS_SH_TMU
diff --git a/arch/arm/mach-shmobile/pm-rmobile.c b/arch/arm/mach-shmobile/pm-rmobile.c
index a4fcd2c..85a7fdd 100644
--- a/arch/arm/mach-shmobile/pm-rmobile.c
+++ b/arch/arm/mach-shmobile/pm-rmobile.c
@@ -3,6 +3,7 @@
*
* Copyright (C) 2012 Renesas Solutions Corp.
* Copyright (C) 2012 Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
+ * Copyright (C) 2014 Glider bvba
*
* based on pm-sh7372.c
* Copyright (C) 2011 Magnus Damm
@@ -13,10 +14,16 @@
*/
#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 */
@@ -30,8 +37,12 @@
static int rmobile_pd_power_down(struct generic_pm_domain *genpd)
{
struct rmobile_pm_domain *rmobile_pd = to_rmobile_pd(genpd);
- unsigned int mask = 1 << rmobile_pd->bit_shift;
+ unsigned int mask;
+
+ if (rmobile_pd->bit_shift == ~0)
+ return -EBUSY;
+ mask = 1 << rmobile_pd->bit_shift;
if (rmobile_pd->suspend) {
int ret = rmobile_pd->suspend();
@@ -61,10 +72,14 @@ static int rmobile_pd_power_down(struct generic_pm_domain *genpd)
static int __rmobile_pd_power_up(struct rmobile_pm_domain *rmobile_pd,
bool do_resume)
{
- unsigned int mask = 1 << rmobile_pd->bit_shift;
+ unsigned int mask;
unsigned int retry_count;
int ret = 0;
+ if (rmobile_pd->bit_shift == ~0)
+ return 0;
+
+ mask = 1 << rmobile_pd->bit_shift;
if (__raw_readl(rmobile_pd->base + PSTR) & mask)
goto out;
@@ -148,6 +163,8 @@ static void rmobile_init_pm_domain(struct rmobile_pm_domain *rmobile_pd)
__rmobile_pd_power_up(rmobile_pd, false);
}
+#ifdef CONFIG_ARCH_SHMOBILE_LEGACY
+
void rmobile_init_domains(struct rmobile_pm_domain domains[], int num)
{
int j;
@@ -180,3 +197,199 @@ void rmobile_add_devices_to_domains(struct pm_domain_device data[],
rmobile_add_device_to_domain_td(data[j].domain_name,
data[j].pdev, &latencies);
}
+
+#else /* !CONFIG_ARCH_SHMOBILE_LEGACY */
+
+static int rmobile_pd_suspend_cpu(void)
+{
+ /*
+ * This domain contains the CPU core and therefore it should
+ * only be turned off if the CPU is not in use.
+ */
+ return -EBUSY;
+}
+
+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;
+}
+
+static int rmobile_pd_suspend_debug(void)
+{
+ /*
+ * This domain contains the Coresight-ETM hardware block and
+ * therefore it should only be turned off if the debug module is
+ * not in use.
+ */
+ return -EBUSY;
+}
+
+#define MAX_NUM_CPU_PDS 8
+
+static unsigned int num_cpu_pds __initdata;
+static struct device_node *cpu_pds[MAX_NUM_CPU_PDS] __initdata;
+static struct device_node *console_pd __initdata;
+static struct device_node *debug_pd __initdata;
+
+static void __init get_special_pds(void)
+{
+ struct device_node *np, *pd;
+ unsigned int i;
+
+ /* PM domains containing CPUs */
+ for_each_node_by_type(np, "cpu") {
+ pd = of_parse_phandle(np, "power-domains", 0);
+ if (!pd)
+ continue;
+
+ for (i = 0; i < num_cpu_pds; i++)
+ if (pd == cpu_pds[i])
+ break;
+
+ if (i < num_cpu_pds) {
+ of_node_put(pd);
+ continue;
+ }
+
+ if (num_cpu_pds == MAX_NUM_CPU_PDS) {
+ pr_warn("Too many CPU PM domains\n");
+ of_node_put(pd);
+ continue;
+ }
+
+ cpu_pds[num_cpu_pds++] = pd;
+ }
+
+ /* PM domain containing console */
+ if (of_stdout)
+ console_pd = of_parse_phandle(of_stdout, "power-domains", 0);
+
+ /* PM domain containing Coresight-ETM */
+ np = of_find_compatible_node(NULL, NULL, "arm,coresight-etm3x");
+ if (np) {
+ debug_pd = of_parse_phandle(np, "power-domains", 0);
+ of_node_put(np);
+ }
+}
+
+static void __init put_special_pds(void)
+{
+ unsigned int i;
+
+ for (i = 0; i < num_cpu_pds; i++)
+ of_node_put(cpu_pds[i]);
+ of_node_put(console_pd);
+ of_node_put(debug_pd);
+}
+
+static bool __init pd_contains_cpu(const struct device_node *pd)
+{
+ unsigned int i;
+
+ for (i = 0; i < num_cpu_pds; i++)
+ if (pd == cpu_pds[i])
+ return true;
+
+ return false;
+}
+
+static void __init rmobile_setup_pm_domain(struct device_node *np,
+ struct rmobile_pm_domain *pd)
+{
+ const char *name = pd->genpd.name;
+
+ if (pd_contains_cpu(np)) {
+ pr_debug("PM domain %s contains CPU\n", name);
+ pd->gov = &pm_domain_always_on_gov;
+ pd->suspend = rmobile_pd_suspend_cpu;
+ } else if (np == console_pd) {
+ pr_debug("PM domain %s contains serial console\n", name);
+ pd->gov = &pm_domain_always_on_gov;
+ pd->suspend = rmobile_pd_suspend_console;
+ } else if (np == debug_pd) {
+ pr_debug("PM domain %s contains Coresight-ETM\n", name);
+ pd->gov = &pm_domain_always_on_gov;
+ pd->suspend = rmobile_pd_suspend_debug;
+ }
+
+ 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)
+ 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("%s cannot map reg 0\n", np->full_name);
+ continue;
+ }
+
+ pmd = of_get_child_by_name(np, "pm-domains");
+ if (!pmd) {
+ pr_warn("%s lacks pm-domains node\n", np->full_name);
+ 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);
+
+#endif /* !CONFIG_ARCH_SHMOBILE_LEGACY */
diff --git a/arch/arm/mach-shmobile/pm-rmobile.h b/arch/arm/mach-shmobile/pm-rmobile.h
index 0602130..5321978 100644
--- a/arch/arm/mach-shmobile/pm-rmobile.h
+++ b/arch/arm/mach-shmobile/pm-rmobile.h
@@ -37,7 +37,7 @@ struct pm_domain_device {
struct platform_device *pdev;
};
-#ifdef CONFIG_PM_RMOBILE
+#if defined(CONFIG_PM_RMOBILE) && defined(CONFIG_ARCH_SHMOBILE_LEGACY)
extern void rmobile_init_domains(struct rmobile_pm_domain domains[], int num);
extern void rmobile_add_device_to_domain_td(const char *domain_name,
struct platform_device *pdev,
--
2.1.4
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