clk: renesas: move drivers to renesas directory

This is part of an ongoing process to migrate from ARCH_SHMOBILE to
ARCH_RENESAS the motivation for which being that RENESAS seems to be a more
appropriate name than SHMOBILE for the majority of Renesas ARM based SoCs.

Along with the above mentioned Kconfig changes it seems appropriate
to also rename directories that only hold drivers for such SoCs.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

1 files changed, 329 insertions, 0 deletions

diff --git a/drivers/clk/renesas/clk-mstp.c b/drivers/clk/renesas/clk-mstp.c
new file mode 100644
index 000000000000..3b09716ebda2
--- /dev/null
+++ b/drivers/clk/renesas/clk-mstp.c
@@ -0,0 +1,329 @@
+/*
+ * R-Car MSTP clocks
+ *
+ * Copyright (C) 2013 Ideas On Board SPRL
+ * Copyright (C) 2015 Glider bvba
+ *
+ * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/shmobile.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/pm_clock.h>
+#include <linux/pm_domain.h>
+#include <linux/spinlock.h>
+
+/*
+ * MSTP clocks. We can't use standard gate clocks as we need to poll on the
+ * status register when enabling the clock.
+ */
+
+#define MSTP_MAX_CLOCKS		32
+
+/**
+ * struct mstp_clock_group - MSTP gating clocks group
+ *
+ * @data: clocks in this group
+ * @smstpcr: module stop control register
+ * @mstpsr: module stop status register (optional)
+ * @lock: protects writes to SMSTPCR
+ */
+struct mstp_clock_group {
+	struct clk_onecell_data data;
+	void __iomem *smstpcr;
+	void __iomem *mstpsr;
+	spinlock_t lock;
+};
+
+/**
+ * struct mstp_clock - MSTP gating clock
+ * @hw: handle between common and hardware-specific interfaces
+ * @bit_index: control bit index
+ * @group: MSTP clocks group
+ */
+struct mstp_clock {
+	struct clk_hw hw;
+	u32 bit_index;
+	struct mstp_clock_group *group;
+};
+
+#define to_mstp_clock(_hw) container_of(_hw, struct mstp_clock, hw)
+
+static int cpg_mstp_clock_endisable(struct clk_hw *hw, bool enable)
+{
+	struct mstp_clock *clock = to_mstp_clock(hw);
+	struct mstp_clock_group *group = clock->group;
+	u32 bitmask = BIT(clock->bit_index);
+	unsigned long flags;
+	unsigned int i;
+	u32 value;
+
+	spin_lock_irqsave(&group->lock, flags);
+
+	value = clk_readl(group->smstpcr);
+	if (enable)
+		value &= ~bitmask;
+	else
+		value |= bitmask;
+	clk_writel(value, group->smstpcr);
+
+	spin_unlock_irqrestore(&group->lock, flags);
+
+	if (!enable || !group->mstpsr)
+		return 0;
+
+	for (i = 1000; i > 0; --i) {
+		if (!(clk_readl(group->mstpsr) & bitmask))
+			break;
+		cpu_relax();
+	}
+
+	if (!i) {
+		pr_err("%s: failed to enable %p[%d]\n", __func__,
+		       group->smstpcr, clock->bit_index);
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static int cpg_mstp_clock_enable(struct clk_hw *hw)
+{
+	return cpg_mstp_clock_endisable(hw, true);
+}
+
+static void cpg_mstp_clock_disable(struct clk_hw *hw)
+{
+	cpg_mstp_clock_endisable(hw, false);
+}
+
+static int cpg_mstp_clock_is_enabled(struct clk_hw *hw)
+{
+	struct mstp_clock *clock = to_mstp_clock(hw);
+	struct mstp_clock_group *group = clock->group;
+	u32 value;
+
+	if (group->mstpsr)
+		value = clk_readl(group->mstpsr);
+	else
+		value = clk_readl(group->smstpcr);
+
+	return !(value & BIT(clock->bit_index));
+}
+
+static const struct clk_ops cpg_mstp_clock_ops = {
+	.enable = cpg_mstp_clock_enable,
+	.disable = cpg_mstp_clock_disable,
+	.is_enabled = cpg_mstp_clock_is_enabled,
+};
+
+static struct clk * __init
+cpg_mstp_clock_register(const char *name, const char *parent_name,
+			unsigned int index, struct mstp_clock_group *group)
+{
+	struct clk_init_data init;
+	struct mstp_clock *clock;
+	struct clk *clk;
+
+	clock = kzalloc(sizeof(*clock), GFP_KERNEL);
+	if (!clock) {
+		pr_err("%s: failed to allocate MSTP clock.\n", __func__);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	init.name = name;
+	init.ops = &cpg_mstp_clock_ops;
+	init.flags = CLK_IS_BASIC | CLK_SET_RATE_PARENT;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+
+	clock->bit_index = index;
+	clock->group = group;
+	clock->hw.init = &init;
+
+	clk = clk_register(NULL, &clock->hw);
+
+	if (IS_ERR(clk))
+		kfree(clock);
+
+	return clk;
+}
+
+static void __init cpg_mstp_clocks_init(struct device_node *np)
+{
+	struct mstp_clock_group *group;
+	const char *idxname;
+	struct clk **clks;
+	unsigned int i;
+
+	group = kzalloc(sizeof(*group), GFP_KERNEL);
+	clks = kmalloc(MSTP_MAX_CLOCKS * sizeof(*clks), GFP_KERNEL);
+	if (group == NULL || clks == NULL) {
+		kfree(group);
+		kfree(clks);
+		pr_err("%s: failed to allocate group\n", __func__);
+		return;
+	}
+
+	spin_lock_init(&group->lock);
+	group->data.clks = clks;
+
+	group->smstpcr = of_iomap(np, 0);
+	group->mstpsr = of_iomap(np, 1);
+
+	if (group->smstpcr == NULL) {
+		pr_err("%s: failed to remap SMSTPCR\n", __func__);
+		kfree(group);
+		kfree(clks);
+		return;
+	}
+
+	for (i = 0; i < MSTP_MAX_CLOCKS; ++i)
+		clks[i] = ERR_PTR(-ENOENT);
+
+	if (of_find_property(np, "clock-indices", &i))
+		idxname = "clock-indices";
+	else
+		idxname = "renesas,clock-indices";
+
+	for (i = 0; i < MSTP_MAX_CLOCKS; ++i) {
+		const char *parent_name;
+		const char *name;
+		u32 clkidx;
+		int ret;
+
+		/* Skip clocks with no name. */
+		ret = of_property_read_string_index(np, "clock-output-names",
+						    i, &name);
+		if (ret < 0 || strlen(name) == 0)
+			continue;
+
+		parent_name = of_clk_get_parent_name(np, i);
+		ret = of_property_read_u32_index(np, idxname, i, &clkidx);
+		if (parent_name == NULL || ret < 0)
+			break;
+
+		if (clkidx >= MSTP_MAX_CLOCKS) {
+			pr_err("%s: invalid clock %s %s index %u\n",
+			       __func__, np->name, name, clkidx);
+			continue;
+		}
+
+		clks[clkidx] = cpg_mstp_clock_register(name, parent_name,
+						       clkidx, group);
+		if (!IS_ERR(clks[clkidx])) {
+			group->data.clk_num = max(group->data.clk_num,
+						  clkidx + 1);
+			/*
+			 * Register a clkdev to let board code retrieve the
+			 * clock by name and register aliases for non-DT
+			 * devices.
+			 *
+			 * FIXME: Remove this when all devices that require a
+			 * clock will be instantiated from DT.
+			 */
+			clk_register_clkdev(clks[clkidx], name, NULL);
+		} else {
+			pr_err("%s: failed to register %s %s clock (%ld)\n",
+			       __func__, np->name, name, PTR_ERR(clks[clkidx]));
+		}
+	}
+
+	of_clk_add_provider(np, of_clk_src_onecell_get, &group->data);
+}
+CLK_OF_DECLARE(cpg_mstp_clks, "renesas,cpg-mstp-clocks", cpg_mstp_clocks_init);
+
+
+#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
+int cpg_mstp_attach_dev(struct generic_pm_domain *domain, struct device *dev)
+{
+	struct device_node *np = dev->of_node;
+	struct of_phandle_args clkspec;
+	struct clk *clk;
+	int i = 0;
+	int error;
+
+	while (!of_parse_phandle_with_args(np, "clocks", "#clock-cells", i,
+					   &clkspec)) {
+		if (of_device_is_compatible(clkspec.np,
+					    "renesas,cpg-mstp-clocks"))
+			goto found;
+
+		/* BSC on r8a73a4/sh73a0 uses zb_clk instead of an mstp clock */
+		if (!strcmp(clkspec.np->name, "zb_clk"))
+			goto found;
+
+		of_node_put(clkspec.np);
+		i++;
+	}
+
+	return 0;
+
+found:
+	clk = of_clk_get_from_provider(&clkspec);
+	of_node_put(clkspec.np);
+
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	error = pm_clk_create(dev);
+	if (error) {
+		dev_err(dev, "pm_clk_create failed %d\n", error);
+		goto fail_put;
+	}
+
+	error = pm_clk_add_clk(dev, clk);
+	if (error) {
+		dev_err(dev, "pm_clk_add_clk %pC failed %d\n", clk, error);
+		goto fail_destroy;
+	}
+
+	return 0;
+
+fail_destroy:
+	pm_clk_destroy(dev);
+fail_put:
+	clk_put(clk);
+	return error;
+}
+
+void cpg_mstp_detach_dev(struct generic_pm_domain *domain, struct device *dev)
+{
+	if (!list_empty(&dev->power.subsys_data->clock_list))
+		pm_clk_destroy(dev);
+}
+
+void __init cpg_mstp_add_clk_domain(struct device_node *np)
+{
+	struct generic_pm_domain *pd;
+	u32 ncells;
+
+	if (of_property_read_u32(np, "#power-domain-cells", &ncells)) {
+		pr_warn("%s lacks #power-domain-cells\n", np->full_name);
+		return;
+	}
+
+	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
+	if (!pd)
+		return;
+
+	pd->name = np->name;
+
+	pd->flags = GENPD_FLAG_PM_CLK;
+	pm_genpd_init(pd, &simple_qos_governor, false);
+	pd->attach_dev = cpg_mstp_attach_dev;
+	pd->detach_dev = cpg_mstp_detach_dev;
+
+	of_genpd_add_provider_simple(np, pd);
+}
+#endif /* !CONFIG_PM_GENERIC_DOMAINS_OF */