Linux-ARM-MSM Archive on lore.kernel.org
 help / color / Atom feed
From: Ulf Hansson <ulf.hansson@linaro.org>
To: Sudeep Holla <sudeep.holla@arm.com>,
	Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>,
	Mark Rutland <mark.rutland@arm.com>,
	linux-arm-kernel@lists.infradead.org
Cc: "Rafael J . Wysocki" <rjw@rjwysocki.net>,
	Daniel Lezcano <daniel.lezcano@linaro.org>,
	"Raju P . L . S . S . S . N" <rplsssn@codeaurora.org>,
	Amit Kucheria <amit.kucheria@linaro.org>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	Stephen Boyd <sboyd@kernel.org>,
	Niklas Cassel <niklas.cassel@linaro.org>,
	Tony Lindgren <tony@atomide.com>,
	Kevin Hilman <khilman@kernel.org>,
	Lina Iyer <ilina@codeaurora.org>,
	Viresh Kumar <viresh.kumar@linaro.org>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Geert Uytterhoeven <geert+renesas@glider.be>,
	Souvik Chakravarty <souvik.chakravarty@arm.com>,
	linux-pm@vger.kernel.org, linux-arm-msm@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Ulf Hansson <ulf.hansson@linaro.org>,
	Lina Iyer <lina.iyer@linaro.org>
Subject: [PATCH 09/18] drivers: firmware: psci: Add support for PM domains using genpd
Date: Mon, 13 May 2019 21:22:51 +0200
Message-ID: <20190513192300.653-10-ulf.hansson@linaro.org> (raw)
In-Reply-To: <20190513192300.653-1-ulf.hansson@linaro.org>

When the hierarchical CPU topology layout is used in DT, we need to setup
the corresponding PM domain data structures, as to allow a CPU and a group
of CPUs to be power managed accordingly. Let's enable this by deploying
support through the genpd interface.

Additionally, when the OS initiated mode is supported by the PSCI FW, let's
also parse the domain idle states DT bindings as to make genpd responsible
for the state selection, when the states are compatible with
"domain-idle-state". Otherwise, when only Platform Coordinated mode is
supported, we rely solely on the state selection to be managed through the
regular cpuidle framework.

If the initialization of the PM domain data structures succeeds and the OS
initiated mode is supported, we try to switch to it. In case it fails,
let's fall back into a degraded mode, rather than bailing out and returning
an error code.

Due to that the OS initiated mode may become enabled, we need to adjust to
maintain backwards compatibility for a kernel started through a kexec call.
Do this by explicitly switch to Platform Coordinated mode during boot.

Finally, the actual initialization of the PM domain data structures, is
done via calling the new shared function, psci_dt_init_pm_domains().
However, this is implemented by subsequent changes.

Co-developed-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---

Changes:
	- Simplify code setting domain_state at power off.
	- Use the genpd ->free_state() callback to manage freeing of states.
	- Fixup a bogus while loop.

---
 drivers/firmware/psci/Makefile         |   2 +-
 drivers/firmware/psci/psci.c           |   7 +-
 drivers/firmware/psci/psci.h           |   5 +
 drivers/firmware/psci/psci_pm_domain.c | 268 +++++++++++++++++++++++++
 4 files changed, 280 insertions(+), 2 deletions(-)
 create mode 100644 drivers/firmware/psci/psci_pm_domain.c

diff --git a/drivers/firmware/psci/Makefile b/drivers/firmware/psci/Makefile
index 1956b882470f..ff300f1fec86 100644
--- a/drivers/firmware/psci/Makefile
+++ b/drivers/firmware/psci/Makefile
@@ -1,4 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0
 #
-obj-$(CONFIG_ARM_PSCI_FW)	+= psci.o
+obj-$(CONFIG_ARM_PSCI_FW)	+= psci.o psci_pm_domain.o
 obj-$(CONFIG_ARM_PSCI_CHECKER)	+= psci_checker.o
diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
index 0e91d864e346..bfef300b7ebe 100644
--- a/drivers/firmware/psci/psci.c
+++ b/drivers/firmware/psci/psci.c
@@ -721,9 +721,14 @@ static int __init psci_1_0_init(struct device_node *np)
 	if (err)
 		return err;
 
-	if (psci_has_osi_support())
+	if (psci_has_osi_support()) {
 		pr_info("OSI mode supported.\n");
 
+		/* Make sure we default to PC mode. */
+		invoke_psci_fn(PSCI_1_0_FN_SET_SUSPEND_MODE,
+			       PSCI_1_0_SUSPEND_MODE_PC, 0, 0);
+	}
+
 	return 0;
 }
 
diff --git a/drivers/firmware/psci/psci.h b/drivers/firmware/psci/psci.h
index f2277c3ad405..00d2e3dcef49 100644
--- a/drivers/firmware/psci/psci.h
+++ b/drivers/firmware/psci/psci.h
@@ -11,6 +11,11 @@ bool psci_has_osi_support(void);
 #ifdef CONFIG_CPU_IDLE
 void psci_set_domain_state(u32 state);
 int psci_dt_parse_state_node(struct device_node *np, u32 *state);
+#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
+int psci_dt_init_pm_domains(struct device_node *np);
+#else
+static inline int psci_dt_init_pm_domains(struct device_node *np) { return 0; }
+#endif
 #endif
 
 #endif /* __PSCI_H */
diff --git a/drivers/firmware/psci/psci_pm_domain.c b/drivers/firmware/psci/psci_pm_domain.c
new file mode 100644
index 000000000000..3c6ca846caf4
--- /dev/null
+++ b/drivers/firmware/psci/psci_pm_domain.c
@@ -0,0 +1,268 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PM domains for CPUs via genpd - managed by PSCI.
+ *
+ * Copyright (C) 2019 Linaro Ltd.
+ * Author: Ulf Hansson <ulf.hansson@linaro.org>
+ *
+ */
+
+#define pr_fmt(fmt) "psci: " fmt
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/pm_domain.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+#include "psci.h"
+
+#if defined(CONFIG_CPU_IDLE) && defined(CONFIG_PM_GENERIC_DOMAINS_OF)
+
+struct psci_pd_provider {
+	struct list_head link;
+	struct device_node *node;
+};
+
+static LIST_HEAD(psci_pd_providers);
+static bool osi_mode_enabled;
+
+static int psci_pd_power_off(struct generic_pm_domain *pd)
+{
+	struct genpd_power_state *state = &pd->states[pd->state_idx];
+	u32 *pd_state;
+
+	/* If we have failed to enable OSI mode, then abort power off. */
+	if (psci_has_osi_support() && !osi_mode_enabled)
+		return -EBUSY;
+
+	if (!state->data)
+		return 0;
+
+	/* When OSI mode is enabled, set the corresponding domain state. */
+	pd_state = state->data;
+	psci_set_domain_state(*pd_state);
+
+	return 0;
+}
+
+static int psci_pd_parse_state_nodes(struct genpd_power_state *states,
+				int state_count)
+{
+	int i, ret;
+	u32 psci_state, *psci_state_buf;
+
+	for (i = 0; i < state_count; i++) {
+		ret = psci_dt_parse_state_node(to_of_node(states[i].fwnode),
+					&psci_state);
+		if (ret)
+			goto free_state;
+
+		psci_state_buf = kmalloc(sizeof(u32), GFP_KERNEL);
+		if (!psci_state_buf) {
+			ret = -ENOMEM;
+			goto free_state;
+		}
+		*psci_state_buf = psci_state;
+		states[i].data = psci_state_buf;
+	}
+
+	return 0;
+
+free_state:
+	i--;
+	for (; i >= 0; i--)
+		kfree(states[i].data);
+	return ret;
+}
+
+static int psci_pd_parse_states(struct device_node *np,
+			struct genpd_power_state **states, int *state_count)
+{
+	int ret;
+
+	/* Parse the domain idle states. */
+	ret = of_genpd_parse_idle_states(np, states, state_count);
+	if (ret)
+		return ret;
+
+	/* Fill out the PSCI specifics for each found state. */
+	ret = psci_pd_parse_state_nodes(*states, *state_count);
+	if (ret)
+		kfree(*states);
+
+	return ret;
+}
+
+static void psci_pd_free_states(struct genpd_power_state *states,
+				unsigned int state_count)
+{
+	int i;
+
+	for (i = 0; i < state_count; i++)
+		kfree(states[i].data);
+	kfree(states);
+}
+
+static int psci_pd_init(struct device_node *np)
+{
+	struct generic_pm_domain *pd;
+	struct psci_pd_provider *pd_provider;
+	struct dev_power_governor *pd_gov;
+	struct genpd_power_state *states = NULL;
+	int ret = -ENOMEM, state_count = 0;
+
+	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
+	if (!pd)
+		goto out;
+
+	pd_provider = kzalloc(sizeof(*pd_provider), GFP_KERNEL);
+	if (!pd_provider)
+		goto free_pd;
+
+	pd->name = kasprintf(GFP_KERNEL, "%pOF", np);
+	if (!pd->name)
+		goto free_pd_prov;
+
+	/*
+	 * For OSI mode, parse the domain idle states and let genpd manage the
+	 * state selection for those being compatible with "domain-idle-state".
+	 */
+	if (psci_has_osi_support()) {
+		ret = psci_pd_parse_states(np, &states, &state_count);
+		if (ret)
+			goto free_name;
+		pd->free_states = psci_pd_free_states;
+	}
+
+	pd->name = kbasename(pd->name);
+	pd->power_off = psci_pd_power_off;
+	pd->states = states;
+	pd->state_count = state_count;
+	pd->flags |= GENPD_FLAG_IRQ_SAFE | GENPD_FLAG_CPU_DOMAIN;
+
+	/* Use governor for CPU PM domains if it has some states to manage. */
+	pd_gov = state_count > 0 ? &pm_domain_cpu_gov : NULL;
+
+	ret = pm_genpd_init(pd, pd_gov, false);
+	if (ret) {
+		psci_pd_free_states(states, state_count);
+		goto free_name;
+	}
+
+	ret = of_genpd_add_provider_simple(np, pd);
+	if (ret)
+		goto remove_pd;
+
+	pd_provider->node = of_node_get(np);
+	list_add(&pd_provider->link, &psci_pd_providers);
+
+	pr_debug("init PM domain %s\n", pd->name);
+	return 0;
+
+remove_pd:
+	pm_genpd_remove(pd);
+free_name:
+	kfree(pd->name);
+free_pd_prov:
+	kfree(pd_provider);
+free_pd:
+	kfree(pd);
+out:
+	pr_err("failed to init PM domain ret=%d %pOF\n", ret, np);
+	return ret;
+}
+
+static void psci_pd_remove(void)
+{
+	struct psci_pd_provider *pd_provider, *it;
+	struct generic_pm_domain *genpd;
+
+	list_for_each_entry_safe(pd_provider, it, &psci_pd_providers, link) {
+		of_genpd_del_provider(pd_provider->node);
+
+		genpd = of_genpd_remove_last(pd_provider->node);
+		if (!IS_ERR(genpd))
+			kfree(genpd);
+
+		of_node_put(pd_provider->node);
+		list_del(&pd_provider->link);
+		kfree(pd_provider);
+	}
+}
+
+static int psci_pd_init_topology(struct device_node *np)
+{
+	struct device_node *node;
+	struct of_phandle_args child, parent;
+	int ret;
+
+	for_each_child_of_node(np, node) {
+		if (of_parse_phandle_with_args(node, "power-domains",
+					"#power-domain-cells", 0, &parent))
+			continue;
+
+		child.np = node;
+		child.args_count = 0;
+
+		ret = of_genpd_add_subdomain(&parent, &child);
+		of_node_put(parent.np);
+		if (ret) {
+			of_node_put(node);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+int psci_dt_init_pm_domains(struct device_node *np)
+{
+	struct device_node *node;
+	int ret, pd_count = 0;
+
+	/*
+	 * Parse child nodes for the "#power-domain-cells" property and
+	 * initialize a genpd/genpd-of-provider pair when it's found.
+	 */
+	for_each_child_of_node(np, node) {
+		if (!of_find_property(node, "#power-domain-cells", NULL))
+			continue;
+
+		ret = psci_pd_init(node);
+		if (ret)
+			goto put_node;
+
+		pd_count++;
+	}
+
+	/* Bail out if not using the hierarchical CPU topology. */
+	if (!pd_count)
+		return 0;
+
+	/* Link genpd masters/subdomains to model the CPU topology. */
+	ret = psci_pd_init_topology(np);
+	if (ret)
+		goto remove_pd;
+
+	/* Try to enable OSI mode if supported. */
+	if (psci_has_osi_support()) {
+		ret = psci_set_osi_mode();
+		if (ret)
+			pr_warn("failed to enable OSI mode: %d\n", ret);
+		else
+			osi_mode_enabled = true;
+	}
+
+	pr_info("Initialized CPU PM domain topology\n");
+	return pd_count;
+
+put_node:
+	of_node_put(node);
+remove_pd:
+	if (pd_count)
+		psci_pd_remove();
+	pr_err("failed to create CPU PM domains ret=%d\n", ret);
+	return ret;
+}
+#endif
-- 
2.17.1


  parent reply index

Thread overview: 68+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-13 19:22 [PATCH 00/18] ARM/ARM64: Support hierarchical CPU arrangement for PSCI Ulf Hansson
2019-05-13 19:22 ` [PATCH 01/18] dt: psci: Update DT bindings to support hierarchical PSCI states Ulf Hansson
2019-07-19 11:29   ` Lorenzo Pieralisi
2019-05-13 19:22 ` [PATCH 02/18] of: base: Add of_get_cpu_state_node() to get idle states for a CPU node Ulf Hansson
2019-05-13 19:22 ` [PATCH 03/18] cpuidle: dt: Support hierarchical CPU idle states Ulf Hansson
2019-05-13 19:22 ` [PATCH 04/18] ARM/ARM64: cpuidle: Let back-end init ops take the driver as input Ulf Hansson
2019-06-07 15:00   ` Sudeep Holla
2019-06-10 10:20     ` Ulf Hansson
2019-05-13 19:22 ` [PATCH 05/18] drivers: firmware: psci: Simplify state node parsing Ulf Hansson
2019-06-07 15:01   ` Sudeep Holla
2019-05-13 19:22 ` [PATCH 06/18] drivers: firmware: psci: Support hierarchical CPU idle states Ulf Hansson
2019-06-07 15:03   ` Sudeep Holla
2019-05-13 19:22 ` [PATCH 07/18] drivers: firmware: psci: Prepare to use OS initiated suspend mode Ulf Hansson
2019-06-07 15:17   ` Sudeep Holla
2019-06-10 10:21     ` Ulf Hansson
2019-06-10 10:42       ` Sudeep Holla
2019-07-16 14:53   ` Sudeep Holla
2019-05-13 19:22 ` [PATCH 08/18] drivers: firmware: psci: Prepare to support PM domains Ulf Hansson
2019-06-07 15:21   ` Sudeep Holla
2019-05-13 19:22 ` Ulf Hansson [this message]
2019-06-07 15:27   ` [PATCH 09/18] drivers: firmware: psci: Add support for PM domains using genpd Sudeep Holla
2019-06-10 10:21     ` Ulf Hansson
2019-06-10 10:59       ` Sudeep Holla
2019-07-16 15:05   ` Sudeep Holla
2019-07-18 11:04     ` Ulf Hansson
2019-07-18 13:19       ` Sudeep Holla
2019-07-18 17:57         ` Lina Iyer
2019-07-19  9:45           ` Sudeep Holla
2019-05-13 19:22 ` [PATCH 10/18] drivers: firmware: psci: Add hierarchical domain idle states converter Ulf Hansson
2019-07-09 15:31   ` Lorenzo Pieralisi
2019-07-16  8:45     ` Ulf Hansson
2019-07-16 14:51       ` Lorenzo Pieralisi
2019-07-18 11:43         ` Ulf Hansson
2019-07-18 13:36           ` Lorenzo Pieralisi
2019-05-13 19:22 ` [PATCH 11/18] drivers: firmware: psci: Introduce psci_dt_topology_init() Ulf Hansson
2019-05-13 19:22 ` [PATCH 12/18] drivers: firmware: psci: Add a helper to attach a CPU to its PM domain Ulf Hansson
2019-05-13 19:22 ` [PATCH 13/18] drivers: firmware: psci: Attach the CPU's device " Ulf Hansson
2019-05-13 19:22 ` [PATCH 14/18] drivers: firmware: psci: Manage runtime PM in the idle path for CPUs Ulf Hansson
2019-07-16 15:53   ` Lorenzo Pieralisi
2019-07-18 10:35     ` Ulf Hansson
2019-07-18 13:30       ` Lorenzo Pieralisi
2019-07-18 16:54         ` Ulf Hansson
2019-07-18 17:41           ` Lina Iyer
2019-07-18 21:49             ` Ulf Hansson
2019-07-19 10:02               ` Lorenzo Pieralisi
2019-05-13 19:22 ` [PATCH 15/18] drivers: firmware: psci: Support CPU hotplug for the hierarchical model Ulf Hansson
2019-06-07 15:31   ` Sudeep Holla
2019-06-10 10:21     ` Ulf Hansson
2019-06-10 11:02       ` Sudeep Holla
2019-05-13 19:22 ` [PATCH 16/18] arm64: kernel: Respect the hierarchical CPU topology in DT for PSCI Ulf Hansson
2019-05-13 19:22 ` [PATCH 17/18] arm64: dts: Convert to the hierarchical CPU topology layout for MSM8916 Ulf Hansson
2019-07-16 14:47   ` Sudeep Holla
2019-07-16 20:36     ` Lina Iyer
2019-07-17 17:18       ` Sudeep Holla
2019-05-13 19:23 ` [PATCH 18/18] arm64: dts: hikey: Convert to the hierarchical CPU topology layout Ulf Hansson
2019-07-16 14:47   ` Sudeep Holla
2019-07-18 10:48     ` Ulf Hansson
2019-07-18 13:11       ` Sudeep Holla
2019-05-14  8:08 ` [PATCH 00/18] ARM/ARM64: Support hierarchical CPU arrangement for PSCI Rafael J. Wysocki
2019-05-14  8:58   ` Ulf Hansson
2019-06-07 15:42     ` Sudeep Holla
2019-06-07 19:34       ` Bjorn Andersson
2019-06-10 10:32         ` Sudeep Holla
2019-06-10 15:54           ` Ulf Hansson
2019-06-10 17:16             ` Lorenzo Pieralisi
2019-06-10 18:57               ` Ulf Hansson
2019-06-18 11:56                 ` Ulf Hansson
2019-06-07 11:19 ` Ulf Hansson

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190513192300.653-10-ulf.hansson@linaro.org \
    --to=ulf.hansson@linaro.org \
    --cc=Lorenzo.Pieralisi@arm.com \
    --cc=amit.kucheria@linaro.org \
    --cc=bjorn.andersson@linaro.org \
    --cc=daniel.lezcano@linaro.org \
    --cc=geert+renesas@glider.be \
    --cc=ilina@codeaurora.org \
    --cc=khilman@kernel.org \
    --cc=lina.iyer@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-arm-msm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=niklas.cassel@linaro.org \
    --cc=rjw@rjwysocki.net \
    --cc=rplsssn@codeaurora.org \
    --cc=sboyd@kernel.org \
    --cc=souvik.chakravarty@arm.com \
    --cc=sudeep.holla@arm.com \
    --cc=tony@atomide.com \
    --cc=vincent.guittot@linaro.org \
    --cc=viresh.kumar@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-ARM-MSM Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-arm-msm/0 linux-arm-msm/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-arm-msm linux-arm-msm/ https://lore.kernel.org/linux-arm-msm \
		linux-arm-msm@vger.kernel.org
	public-inbox-index linux-arm-msm

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-arm-msm


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git