This patch hooks up the support for device power domain provided by
SCPI using the Linux generic power domain infrastructure.
Cc: "Rafael J. Wysocki" <r...@rjwysocki.net>
Cc: Kevin Hilman <khil...@kernel.org>
Cc: Ulf Hansson <ulf.hans...@linaro.org>
Cc: linux...@vger.kernel.org
Signed-off-by: Sudeep Holla <sudeep.ho...@arm.com>
---
drivers/firmware/Kconfig | 8 +++
drivers/firmware/Makefile | 1 +
drivers/firmware/scpi_pd.c | 152 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 161 insertions(+)
create mode 100644 drivers/firmware/scpi_pd.c
Hi,
Since most of the power controller drivers are place in drivers/soc/<soc_name>,
I am not sure where to put this SCPI power domain code as it can be used
on multiple SoC. I have placed it in drivers/firmware temporarily for
review. Please suggest the most apt place to put this driver.
Regards,
Sudeep
diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
index 41abdc54815e..80c963c60f13 100644
--- a/drivers/firmware/Kconfig
+++ b/drivers/firmware/Kconfig
@@ -27,6 +27,14 @@ config ARM_SCPI_PROTOCOL
This protocol library provides interface for all the client drivers
making use of the features offered by the SCP.
+config ARM_SCPI_POWER_DOMAIN
+ tristate "SCPI power domain driver"
+ depends on (ARM_SCPI_PROTOCOL && PM) || COMPILE_TEST
+ select PM_GENERIC_DOMAINS_OF
+ help
+ This enables support for the SCPI power domains which can be
+ enabled or disabled via the SCP firmware
+
config EDD
tristate "BIOS Enhanced Disk Drive calls determine boot disk"
depends on X86
diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile
index 474bada56fcd..24f7fe8e3fc3 100644
--- a/drivers/firmware/Makefile
+++ b/drivers/firmware/Makefile
@@ -3,6 +3,7 @@
#
obj-$(CONFIG_ARM_PSCI_FW) += psci.o
obj-$(CONFIG_ARM_SCPI_PROTOCOL) += arm_scpi.o
+obj-$(CONFIG_ARM_SCPI_POWER_DOMAIN) += scpi_pd.o
obj-$(CONFIG_DMI) += dmi_scan.o
obj-$(CONFIG_DMI_SYSFS) += dmi-sysfs.o
obj-$(CONFIG_EDD) += edd.o
diff --git a/drivers/firmware/scpi_pd.c b/drivers/firmware/scpi_pd.c
new file mode 100644
index 000000000000..fb24631d2b2e
--- /dev/null
+++ b/drivers/firmware/scpi_pd.c
@@ -0,0 +1,152 @@
+/*
+ * SCPI Generic power domain support.
+ *
+ * Copyright (C) 2016 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_platform.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;
+ char name[20];
+};
+
+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;
+ }
+
+ 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;
+ sprintf(scpi_pd->name, "%s.%d", np->name, i);
+ scpi_pd->genpd.name = scpi_pd->name;
+ 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.ho...@arm.com>");
+MODULE_DESCRIPTION("ARM SCPI power domain driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4
