soc: samsung: Move power-domain driver to the genpd dir

To simplify with maintenance let's move the samsung power-domain driver to
the new genpd directory. Going forward, patches are intended to be managed
through a separate git tree, according to MAINTAINERS.

Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: Alim Akhtar <alim.akhtar@samsung.com>
Cc: <linux-samsung-soc@vger.kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

3 files changed, 169 insertions, 0 deletions

diff --git a/drivers/genpd/Makefile b/drivers/genpd/Makefile
index c178421e0cbc..1cf0ff26a44f 100644
--- a/drivers/genpd/Makefile
+++ b/drivers/genpd/Makefile
@@ -7,3 +7,4 @@ obj-y					+= mediatek/
 obj-y					+= qcom/
 obj-y					+= renesas/
 obj-y					+= rockchip/
+obj-y					+= samsung/
diff --git a/drivers/genpd/samsung/Makefile b/drivers/genpd/samsung/Makefile
new file mode 100644
index 000000000000..397aa5908c1d
--- /dev/null
+++ b/drivers/genpd/samsung/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_EXYNOS_PM_DOMAINS)		+= exynos-pm-domains.o
diff --git a/drivers/genpd/samsung/exynos-pm-domains.c b/drivers/genpd/samsung/exynos-pm-domains.c
new file mode 100644
index 000000000000..d07f3c9d6903
--- /dev/null
+++ b/drivers/genpd/samsung/exynos-pm-domains.c
@@ -0,0 +1,166 @@
+// 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/slab.h>
+#include <linux/pm_domain.h>
+#include <linux/delay.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.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);