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-rw-r--r--drivers/pmdomain/arm/Kconfig37
-rw-r--r--drivers/pmdomain/arm/Makefile1
-rw-r--r--drivers/pmdomain/arm/scpi_pm_domain.c157
3 files changed, 195 insertions, 0 deletions
diff --git a/drivers/pmdomain/arm/Kconfig b/drivers/pmdomain/arm/Kconfig
new file mode 100644
index 0000000000..efa139c34e
--- /dev/null
+++ b/drivers/pmdomain/arm/Kconfig
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config ARM_SCMI_PERF_DOMAIN
+ tristate "SCMI performance domain driver"
+ depends on ARM_SCMI_PROTOCOL || (COMPILE_TEST && OF)
+ default y
+ select PM_GENERIC_DOMAINS if PM
+ help
+ This enables support for the SCMI performance domains which can be
+ enabled or disabled via the SCP firmware.
+
+ This driver can also be built as a module. If so, the module will be
+ called scmi_perf_domain.
+
+config ARM_SCMI_POWER_DOMAIN
+ tristate "SCMI power domain driver"
+ depends on ARM_SCMI_PROTOCOL || (COMPILE_TEST && OF)
+ default y
+ select PM_GENERIC_DOMAINS if PM
+ help
+ This enables support for the SCMI power domains which can be
+ enabled or disabled via the SCP firmware
+
+ This driver can also be built as a module. If so, the module
+ will be called scmi_pm_domain. Note this may needed early in boot
+ before rootfs may be available.
+
+config ARM_SCPI_POWER_DOMAIN
+ tristate "SCPI power domain driver"
+ depends on ARM_SCPI_PROTOCOL || (COMPILE_TEST && OF)
+ default y
+ select PM_GENERIC_DOMAINS if PM
+ help
+ This enables support for the SCPI power domains which can be
+ enabled or disabled via the SCP firmware
+
+ This driver can also be built as a module. If so, the module will be
+ called scpi_pm_domain.
diff --git a/drivers/pmdomain/arm/Makefile b/drivers/pmdomain/arm/Makefile
index cfcb1f6cdd..502fe4d0a8 100644
--- a/drivers/pmdomain/arm/Makefile
+++ b/drivers/pmdomain/arm/Makefile
@@ -2,3 +2,4 @@
obj-$(CONFIG_ARM_SCMI_PERF_DOMAIN) += scmi_perf_domain.o
obj-$(CONFIG_ARM_SCMI_POWER_DOMAIN) += scmi_pm_domain.o
+obj-$(CONFIG_ARM_SCPI_POWER_DOMAIN) += scpi_pm_domain.o
diff --git a/drivers/pmdomain/arm/scpi_pm_domain.c b/drivers/pmdomain/arm/scpi_pm_domain.c
new file mode 100644
index 0000000000..2231e6dd20
--- /dev/null
+++ b/drivers/pmdomain/arm/scpi_pm_domain.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SCPI Generic power domain support.
+ *
+ * Copyright (C) 2016 ARM Ltd.
+ */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/scpi_protocol.h>
+
+struct scpi_pm_domain {
+ struct generic_pm_domain genpd;
+ struct scpi_ops *ops;
+ u32 domain;
+};
+
+/*
+ * These device power state values are not well-defined in the specification.
+ * In case, different implementations use different values, we can make these
+ * specific to compatibles rather than getting these values from device tree.
+ */
+enum scpi_power_domain_state {
+ SCPI_PD_STATE_ON = 0,
+ SCPI_PD_STATE_OFF = 3,
+};
+
+#define to_scpi_pd(gpd) container_of(gpd, struct scpi_pm_domain, genpd)
+
+static int scpi_pd_power(struct scpi_pm_domain *pd, bool power_on)
+{
+ int ret;
+ enum scpi_power_domain_state state;
+
+ if (power_on)
+ state = SCPI_PD_STATE_ON;
+ else
+ state = SCPI_PD_STATE_OFF;
+
+ ret = pd->ops->device_set_power_state(pd->domain, state);
+ if (ret)
+ return ret;
+
+ return !(state == pd->ops->device_get_power_state(pd->domain));
+}
+
+static int scpi_pd_power_on(struct generic_pm_domain *domain)
+{
+ struct scpi_pm_domain *pd = to_scpi_pd(domain);
+
+ return scpi_pd_power(pd, true);
+}
+
+static int scpi_pd_power_off(struct generic_pm_domain *domain)
+{
+ struct scpi_pm_domain *pd = to_scpi_pd(domain);
+
+ return scpi_pd_power(pd, false);
+}
+
+static int scpi_pm_domain_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct scpi_pm_domain *scpi_pd;
+ struct genpd_onecell_data *scpi_pd_data;
+ struct generic_pm_domain **domains;
+ struct scpi_ops *scpi_ops;
+ int ret, num_domains, i;
+
+ scpi_ops = get_scpi_ops();
+ if (!scpi_ops)
+ return -EPROBE_DEFER;
+
+ if (!np) {
+ dev_err(dev, "device tree node not found\n");
+ return -ENODEV;
+ }
+
+ if (!scpi_ops->device_set_power_state ||
+ !scpi_ops->device_get_power_state) {
+ dev_err(dev, "power domains not supported in the firmware\n");
+ return -ENODEV;
+ }
+
+ ret = of_property_read_u32(np, "num-domains", &num_domains);
+ if (ret) {
+ dev_err(dev, "number of domains not found\n");
+ return -EINVAL;
+ }
+
+ scpi_pd = devm_kcalloc(dev, num_domains, sizeof(*scpi_pd), GFP_KERNEL);
+ if (!scpi_pd)
+ return -ENOMEM;
+
+ scpi_pd_data = devm_kzalloc(dev, sizeof(*scpi_pd_data), GFP_KERNEL);
+ if (!scpi_pd_data)
+ return -ENOMEM;
+
+ domains = devm_kcalloc(dev, num_domains, sizeof(*domains), GFP_KERNEL);
+ if (!domains)
+ return -ENOMEM;
+
+ for (i = 0; i < num_domains; i++, scpi_pd++) {
+ domains[i] = &scpi_pd->genpd;
+
+ scpi_pd->domain = i;
+ scpi_pd->ops = scpi_ops;
+ scpi_pd->genpd.name = devm_kasprintf(dev, GFP_KERNEL,
+ "%pOFn.%d", np, i);
+ if (!scpi_pd->genpd.name) {
+ dev_err(dev, "Failed to allocate genpd name:%pOFn.%d\n",
+ np, i);
+ continue;
+ }
+ scpi_pd->genpd.power_off = scpi_pd_power_off;
+ scpi_pd->genpd.power_on = scpi_pd_power_on;
+
+ /*
+ * Treat all power domains as off at boot.
+ *
+ * The SCP firmware itself may have switched on some domains,
+ * but for reference counting purpose, keep it this way.
+ */
+ pm_genpd_init(&scpi_pd->genpd, NULL, true);
+ }
+
+ scpi_pd_data->domains = domains;
+ scpi_pd_data->num_domains = num_domains;
+
+ of_genpd_add_provider_onecell(np, scpi_pd_data);
+
+ return 0;
+}
+
+static const struct of_device_id scpi_power_domain_ids[] = {
+ { .compatible = "arm,scpi-power-domains", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, scpi_power_domain_ids);
+
+static struct platform_driver scpi_power_domain_driver = {
+ .driver = {
+ .name = "scpi_power_domain",
+ .of_match_table = scpi_power_domain_ids,
+ },
+ .probe = scpi_pm_domain_probe,
+};
+module_platform_driver(scpi_power_domain_driver);
+
+MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
+MODULE_DESCRIPTION("ARM SCPI power domain driver");
+MODULE_LICENSE("GPL v2");