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Diffstat (limited to 'drivers/pmdomain/samsung/exynos-pm-domains.c')
-rw-r--r--drivers/pmdomain/samsung/exynos-pm-domains.c167
1 files changed, 167 insertions, 0 deletions
diff --git a/drivers/pmdomain/samsung/exynos-pm-domains.c b/drivers/pmdomain/samsung/exynos-pm-domains.c
new file mode 100644
index 0000000000..9b502e8751
--- /dev/null
+++ b/drivers/pmdomain/samsung/exynos-pm-domains.c
@@ -0,0 +1,167 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Exynos Generic power domain support.
+//
+// Copyright (c) 2012 Samsung Electronics Co., Ltd.
+// http://www.samsung.com
+//
+// Implementation of Exynos specific power domain control which is used in
+// conjunction with runtime-pm. Support for both device-tree and non-device-tree
+// based power domain support is included.
+
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/pm_domain.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/pm_runtime.h>
+
+struct exynos_pm_domain_config {
+ /* Value for LOCAL_PWR_CFG and STATUS fields for each domain */
+ u32 local_pwr_cfg;
+};
+
+/*
+ * Exynos specific wrapper around the generic power domain
+ */
+struct exynos_pm_domain {
+ void __iomem *base;
+ struct generic_pm_domain pd;
+ u32 local_pwr_cfg;
+};
+
+static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
+{
+ struct exynos_pm_domain *pd;
+ void __iomem *base;
+ u32 timeout, pwr;
+ char *op;
+
+ pd = container_of(domain, struct exynos_pm_domain, pd);
+ base = pd->base;
+
+ pwr = power_on ? pd->local_pwr_cfg : 0;
+ writel_relaxed(pwr, base);
+
+ /* Wait max 1ms */
+ timeout = 10;
+
+ while ((readl_relaxed(base + 0x4) & pd->local_pwr_cfg) != pwr) {
+ if (!timeout) {
+ op = (power_on) ? "enable" : "disable";
+ pr_err("Power domain %s %s failed\n", domain->name, op);
+ return -ETIMEDOUT;
+ }
+ timeout--;
+ cpu_relax();
+ usleep_range(80, 100);
+ }
+
+ return 0;
+}
+
+static int exynos_pd_power_on(struct generic_pm_domain *domain)
+{
+ return exynos_pd_power(domain, true);
+}
+
+static int exynos_pd_power_off(struct generic_pm_domain *domain)
+{
+ return exynos_pd_power(domain, false);
+}
+
+static const struct exynos_pm_domain_config exynos4210_cfg = {
+ .local_pwr_cfg = 0x7,
+};
+
+static const struct exynos_pm_domain_config exynos5433_cfg = {
+ .local_pwr_cfg = 0xf,
+};
+
+static const struct of_device_id exynos_pm_domain_of_match[] = {
+ {
+ .compatible = "samsung,exynos4210-pd",
+ .data = &exynos4210_cfg,
+ }, {
+ .compatible = "samsung,exynos5433-pd",
+ .data = &exynos5433_cfg,
+ },
+ { },
+};
+
+static const char *exynos_get_domain_name(struct device_node *node)
+{
+ const char *name;
+
+ if (of_property_read_string(node, "label", &name) < 0)
+ name = kbasename(node->full_name);
+ return kstrdup_const(name, GFP_KERNEL);
+}
+
+static int exynos_pd_probe(struct platform_device *pdev)
+{
+ const struct exynos_pm_domain_config *pm_domain_cfg;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct of_phandle_args child, parent;
+ struct exynos_pm_domain *pd;
+ int on, ret;
+
+ pm_domain_cfg = of_device_get_match_data(dev);
+ pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
+ if (!pd)
+ return -ENOMEM;
+
+ pd->pd.name = exynos_get_domain_name(np);
+ if (!pd->pd.name)
+ return -ENOMEM;
+
+ pd->base = of_iomap(np, 0);
+ if (!pd->base) {
+ kfree_const(pd->pd.name);
+ return -ENODEV;
+ }
+
+ pd->pd.power_off = exynos_pd_power_off;
+ pd->pd.power_on = exynos_pd_power_on;
+ pd->local_pwr_cfg = pm_domain_cfg->local_pwr_cfg;
+
+ on = readl_relaxed(pd->base + 0x4) & pd->local_pwr_cfg;
+
+ pm_genpd_init(&pd->pd, NULL, !on);
+ ret = of_genpd_add_provider_simple(np, &pd->pd);
+
+ if (ret == 0 && of_parse_phandle_with_args(np, "power-domains",
+ "#power-domain-cells", 0, &parent) == 0) {
+ child.np = np;
+ child.args_count = 0;
+
+ if (of_genpd_add_subdomain(&parent, &child))
+ pr_warn("%pOF failed to add subdomain: %pOF\n",
+ parent.np, child.np);
+ else
+ pr_info("%pOF has as child subdomain: %pOF.\n",
+ parent.np, child.np);
+ }
+
+ pm_runtime_enable(dev);
+ return ret;
+}
+
+static struct platform_driver exynos_pd_driver = {
+ .probe = exynos_pd_probe,
+ .driver = {
+ .name = "exynos-pd",
+ .of_match_table = exynos_pm_domain_of_match,
+ .suppress_bind_attrs = true,
+ }
+};
+
+static __init int exynos4_pm_init_power_domain(void)
+{
+ return platform_driver_register(&exynos_pd_driver);
+}
+core_initcall(exynos4_pm_init_power_domain);