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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/cpuidle/cpuidle-psci-domain.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/cpuidle/cpuidle-psci-domain.c')
-rw-r--r--drivers/cpuidle/cpuidle-psci-domain.c203
1 files changed, 203 insertions, 0 deletions
diff --git a/drivers/cpuidle/cpuidle-psci-domain.c b/drivers/cpuidle/cpuidle-psci-domain.c
new file mode 100644
index 0000000000..b88af1262f
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-psci-domain.c
@@ -0,0 +1,203 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PM domains for CPUs via genpd - managed by cpuidle-psci.
+ *
+ * Copyright (C) 2019 Linaro Ltd.
+ * Author: Ulf Hansson <ulf.hansson@linaro.org>
+ *
+ */
+
+#define pr_fmt(fmt) "CPUidle PSCI: " fmt
+
+#include <linux/cpu.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+#include <linux/psci.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+#include "cpuidle-psci.h"
+
+struct psci_pd_provider {
+ struct list_head link;
+ struct device_node *node;
+};
+
+static LIST_HEAD(psci_pd_providers);
+static bool psci_pd_allow_domain_state;
+
+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 (!state->data)
+ return 0;
+
+ if (!psci_pd_allow_domain_state)
+ return -EBUSY;
+
+ /* 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_init(struct device_node *np, bool use_osi)
+{
+ struct generic_pm_domain *pd;
+ struct psci_pd_provider *pd_provider;
+ struct dev_power_governor *pd_gov;
+ int ret = -ENOMEM;
+
+ pd = dt_idle_pd_alloc(np, psci_dt_parse_state_node);
+ if (!pd)
+ goto out;
+
+ pd_provider = kzalloc(sizeof(*pd_provider), GFP_KERNEL);
+ if (!pd_provider)
+ goto free_pd;
+
+ pd->flags |= GENPD_FLAG_IRQ_SAFE | GENPD_FLAG_CPU_DOMAIN;
+
+ /*
+ * Allow power off when OSI has been successfully enabled.
+ * PREEMPT_RT is not yet ready to enter domain idle states.
+ */
+ if (use_osi && !IS_ENABLED(CONFIG_PREEMPT_RT))
+ pd->power_off = psci_pd_power_off;
+ else
+ pd->flags |= GENPD_FLAG_ALWAYS_ON;
+
+ /* Use governor for CPU PM domains if it has some states to manage. */
+ pd_gov = pd->states ? &pm_domain_cpu_gov : NULL;
+
+ ret = pm_genpd_init(pd, pd_gov, false);
+ if (ret)
+ goto free_pd_prov;
+
+ 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_pd_prov:
+ kfree(pd_provider);
+free_pd:
+ dt_idle_pd_free(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_reverse(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 void psci_cpuidle_domain_sync_state(struct device *dev)
+{
+ /*
+ * All devices have now been attached/probed to the PM domain topology,
+ * hence it's fine to allow domain states to be picked.
+ */
+ psci_pd_allow_domain_state = true;
+}
+
+static const struct of_device_id psci_of_match[] = {
+ { .compatible = "arm,psci-1.0" },
+ {}
+};
+
+static int psci_cpuidle_domain_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct device_node *node;
+ bool use_osi = psci_has_osi_support();
+ int ret = 0, pd_count = 0;
+
+ if (!np)
+ return -ENODEV;
+
+ /*
+ * 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_property_present(node, "#power-domain-cells"))
+ continue;
+
+ ret = psci_pd_init(node, use_osi);
+ if (ret) {
+ of_node_put(node);
+ goto exit;
+ }
+
+ 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 = dt_idle_pd_init_topology(np);
+ if (ret)
+ goto remove_pd;
+
+ /* let's try to enable OSI. */
+ ret = psci_set_osi_mode(use_osi);
+ if (ret)
+ goto remove_pd;
+
+ pr_info("Initialized CPU PM domain topology using %s mode\n",
+ use_osi ? "OSI" : "PC");
+ return 0;
+
+remove_pd:
+ dt_idle_pd_remove_topology(np);
+ psci_pd_remove();
+exit:
+ pr_err("failed to create CPU PM domains ret=%d\n", ret);
+ return ret;
+}
+
+static struct platform_driver psci_cpuidle_domain_driver = {
+ .probe = psci_cpuidle_domain_probe,
+ .driver = {
+ .name = "psci-cpuidle-domain",
+ .of_match_table = psci_of_match,
+ .sync_state = psci_cpuidle_domain_sync_state,
+ },
+};
+
+static int __init psci_idle_init_domains(void)
+{
+ return platform_driver_register(&psci_cpuidle_domain_driver);
+}
+subsys_initcall(psci_idle_init_domains);