1 files changed, 596 insertions, 0 deletions
diff --git a/drivers/clk/shmobile/renesas-cpg-mssr.c b/drivers/clk/shmobile/renesas-cpg-mssr.c
new file mode 100644
index 000000000000..9a4d888164bb
--- /dev/null
+++ b/drivers/clk/shmobile/renesas-cpg-mssr.c
@@ -0,0 +1,596 @@
+/*
+ * Renesas Clock Pulse Generator / Module Standby and Software Reset
+ *
+ * Copyright (C) 2015 Glider bvba
+ *
+ * Based on clk-mstp.c, clk-rcar-gen2.c, and clk-rcar-gen3.c
+ *
+ * Copyright (C) 2013 Ideas On Board SPRL
+ * Copyright (C) 2015 Renesas Electronics Corp.
+ *
+ * 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/device.h>
+#include <linux/init.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_clock.h>
+#include <linux/pm_domain.h>
+#include <linux/slab.h>
+
+#include <dt-bindings/clock/renesas-cpg-mssr.h>
+
+#include "renesas-cpg-mssr.h"
+#include "clk-div6.h"
+
+#ifdef DEBUG
+#define WARN_DEBUG(x)	do { } while (0)
+#else
+#define WARN_DEBUG(x)	WARN_ON(x)
+#endif
+
+
+/*
+ * Module Standby and Software Reset register offets.
+ *
+ * If the registers exist, these are valid for SH-Mobile, R-Mobile,
+ * R-Car Gen 2, and R-Car Gen 3.
+ * These are NOT valid for R-Car Gen1 and RZ/A1!
+ */
+
+/*
+ * Module Stop Status Register offsets
+ */
+
+static const u16 mstpsr[] = {
+	0x030, 0x038, 0x040, 0x048, 0x04C, 0x03C, 0x1C0, 0x1C4,
+	0x9A0, 0x9A4, 0x9A8, 0x9AC,
+};
+
+#define	MSTPSR(i)	mstpsr[i]
+
+
+/*
+ * System Module Stop Control Register offsets
+ */
+
+static const u16 smstpcr[] = {
+	0x130, 0x134, 0x138, 0x13C, 0x140, 0x144, 0x148, 0x14C,
+	0x990, 0x994, 0x998, 0x99C,
+};
+
+#define	SMSTPCR(i)	smstpcr[i]
+
+
+/*
+ * Software Reset Register offsets
+ */
+
+static const u16 srcr[] = {
+	0x0A0, 0x0A8, 0x0B0, 0x0B8, 0x0BC, 0x0C4, 0x1C8, 0x1CC,
+	0x920, 0x924, 0x928, 0x92C,
+};
+
+#define	SRCR(i)		srcr[i]
+
+
+/* Realtime Module Stop Control Register offsets */
+#define RMSTPCR(i)	(smstpcr[i] - 0x20)
+
+/* Modem Module Stop Control Register offsets (r8a73a4) */
+#define MMSTPCR(i)	(smstpcr[i] + 0x20)
+
+/* Software Reset Clearing Register offsets */
+#define	SRSTCLR(i)	(0x940 + (i) * 4)
+
+
+/**
+ * Clock Pulse Generator / Module Standby and Software Reset Private Data
+ *
+ * @dev: CPG/MSSR device
+ * @base: CPG/MSSR register block base address
+ * @mstp_lock: protects writes to SMSTPCR
+ * @clks: Array containing all Core and Module Clocks
+ * @num_core_clks: Number of Core Clocks in clks[]
+ * @num_mod_clks: Number of Module Clocks in clks[]
+ * @last_dt_core_clk: ID of the last Core Clock exported to DT
+ */
+struct cpg_mssr_priv {
+	struct device *dev;
+	void __iomem *base;
+	spinlock_t mstp_lock;
+
+	struct clk **clks;
+	unsigned int num_core_clks;
+	unsigned int num_mod_clks;
+	unsigned int last_dt_core_clk;
+};
+
+
+/**
+ * struct mstp_clock - MSTP gating clock
+ * @hw: handle between common and hardware-specific interfaces
+ * @index: MSTP clock number
+ * @priv: CPG/MSSR private data
+ */
+struct mstp_clock {
+	struct clk_hw hw;
+	u32 index;
+	struct cpg_mssr_priv *priv;
+};
+
+#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 cpg_mssr_priv *priv = clock->priv;
+	unsigned int reg = clock->index / 32;
+	unsigned int bit = clock->index % 32;
+	struct device *dev = priv->dev;
+	u32 bitmask = BIT(bit);
+	unsigned long flags;
+	unsigned int i;
+	u32 value;
+
+	dev_dbg(dev, "MSTP %u%02u/%pC %s\n", reg, bit, hw->clk,
+		enable ? "ON" : "OFF");
+	spin_lock_irqsave(&priv->mstp_lock, flags);
+
+	value = clk_readl(priv->base + SMSTPCR(reg));
+	if (enable)
+		value &= ~bitmask;
+	else
+		value |= bitmask;
+	clk_writel(value, priv->base + SMSTPCR(reg));
+
+	spin_unlock_irqrestore(&priv->mstp_lock, flags);
+
+	if (!enable)
+		return 0;
+
+	for (i = 1000; i > 0; --i) {
+		if (!(clk_readl(priv->base + MSTPSR(reg)) &
+		      bitmask))
+			break;
+		cpu_relax();
+	}
+
+	if (!i) {
+		dev_err(dev, "Failed to enable SMSTP %p[%d]\n",
+			priv->base + SMSTPCR(reg), bit);
+		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 cpg_mssr_priv *priv = clock->priv;
+	u32 value;
+
+	value = clk_readl(priv->base + MSTPSR(clock->index / 32));
+
+	return !(value & BIT(clock->index % 32));
+}
+
+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 *cpg_mssr_clk_src_twocell_get(struct of_phandle_args *clkspec,
+					 void *data)
+{
+	unsigned int clkidx = clkspec->args[1];
+	struct cpg_mssr_priv *priv = data;
+	struct device *dev = priv->dev;
+	unsigned int idx;
+	const char *type;
+	struct clk *clk;
+
+	switch (clkspec->args[0]) {
+	case CPG_CORE:
+		type = "core";
+		if (clkidx > priv->last_dt_core_clk) {
+			dev_err(dev, "Invalid %s clock index %u\n", type,
+			       clkidx);
+			return ERR_PTR(-EINVAL);
+		}
+		clk = priv->clks[clkidx];
+		break;
+
+	case CPG_MOD:
+		type = "module";
+		idx = MOD_CLK_PACK(clkidx);
+		if (clkidx % 100 > 31 || idx >= priv->num_mod_clks) {
+			dev_err(dev, "Invalid %s clock index %u\n", type,
+				clkidx);
+			return ERR_PTR(-EINVAL);
+		}
+		clk = priv->clks[priv->num_core_clks + idx];
+		break;
+
+	default:
+		dev_err(dev, "Invalid CPG clock type %u\n", clkspec->args[0]);
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (IS_ERR(clk))
+		dev_err(dev, "Cannot get %s clock %u: %ld", type, clkidx,
+		       PTR_ERR(clk));
+	else
+		dev_dbg(dev, "clock (%u, %u) is %pC at %pCr Hz\n",
+			clkspec->args[0], clkspec->args[1], clk, clk);
+	return clk;
+}
+
+static void __init cpg_mssr_register_core_clk(const struct cpg_core_clk *core,
+					      const struct cpg_mssr_info *info,
+					      struct cpg_mssr_priv *priv)
+{
+	struct clk *clk = NULL, *parent;
+	struct device *dev = priv->dev;
+	unsigned int id = core->id;
+	const char *parent_name;
+
+	WARN_DEBUG(id >= priv->num_core_clks);
+	WARN_DEBUG(PTR_ERR(priv->clks[id]) != -ENOENT);
+
+	switch (core->type) {
+	case CLK_TYPE_IN:
+		clk = of_clk_get_by_name(priv->dev->of_node, core->name);
+		break;
+
+	case CLK_TYPE_FF:
+	case CLK_TYPE_DIV6P1:
+		WARN_DEBUG(core->parent >= priv->num_core_clks);
+		parent = priv->clks[core->parent];
+		if (IS_ERR(parent)) {
+			clk = parent;
+			goto fail;
+		}
+
+		parent_name = __clk_get_name(parent);
+		if (core->type == CLK_TYPE_FF) {
+			clk = clk_register_fixed_factor(NULL, core->name,
+							parent_name, 0,
+							core->mult, core->div);
+		} else {
+			clk = cpg_div6_register(core->name, 1, &parent_name,
+						priv->base + core->offset);
+		}
+		break;
+
+	default:
+		if (info->cpg_clk_register)
+			clk = info->cpg_clk_register(dev, core, info,
+						     priv->clks, priv->base);
+		else
+			dev_err(dev, "%s has unsupported core clock type %u\n",
+				core->name, core->type);
+		break;
+	}
+
+	if (IS_ERR_OR_NULL(clk))
+		goto fail;
+
+	dev_dbg(dev, "Core clock %pC at %pCr Hz\n", clk, clk);
+	priv->clks[id] = clk;
+	return;
+
+fail:
+	dev_err(dev, "Failed to register %s clock %s: %ld\n", "core,",
+		core->name, PTR_ERR(clk));
+}
+
+static void __init cpg_mssr_register_mod_clk(const struct mssr_mod_clk *mod,
+					     const struct cpg_mssr_info *info,
+					     struct cpg_mssr_priv *priv)
+{
+	struct mstp_clock *clock = NULL;
+	struct device *dev = priv->dev;
+	unsigned int id = mod->id;
+	struct clk_init_data init;
+	struct clk *parent, *clk;
+	const char *parent_name;
+	unsigned int i;
+
+	WARN_DEBUG(id < priv->num_core_clks);
+	WARN_DEBUG(id >= priv->num_core_clks + priv->num_mod_clks);
+	WARN_DEBUG(mod->parent >= priv->num_core_clks + priv->num_mod_clks);
+	WARN_DEBUG(PTR_ERR(priv->clks[id]) != -ENOENT);
+
+	parent = priv->clks[mod->parent];
+	if (IS_ERR(parent)) {
+		clk = parent;
+		goto fail;
+	}
+
+	clock = kzalloc(sizeof(*clock), GFP_KERNEL);
+	if (!clock) {
+		clk = ERR_PTR(-ENOMEM);
+		goto fail;
+	}
+
+	init.name = mod->name;
+	init.ops = &cpg_mstp_clock_ops;
+	init.flags = CLK_IS_BASIC | CLK_SET_RATE_PARENT;
+	for (i = 0; i < info->num_crit_mod_clks; i++)
+		if (id == info->crit_mod_clks[i]) {
+#ifdef CLK_ENABLE_HAND_OFF
+			dev_dbg(dev, "MSTP %s setting CLK_ENABLE_HAND_OFF\n",
+				mod->name);
+			init.flags |= CLK_ENABLE_HAND_OFF;
+			break;
+#else
+			dev_dbg(dev, "Ignoring MSTP %s to prevent disabling\n",
+				mod->name);
+			return;
+#endif
+		}
+
+	parent_name = __clk_get_name(parent);
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+
+	clock->index = id - priv->num_core_clks;
+	clock->priv = priv;
+	clock->hw.init = &init;
+
+	clk = clk_register(NULL, &clock->hw);
+	if (IS_ERR(clk))
+		goto fail;
+
+	dev_dbg(dev, "Module clock %pC at %pCr Hz\n", clk, clk);
+	priv->clks[id] = clk;
+	return;
+
+fail:
+	dev_err(dev, "Failed to register %s clock %s: %ld\n", "module,",
+		mod->name, PTR_ERR(clk));
+	kfree(clock);
+}
+
+
+#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
+struct cpg_mssr_clk_domain {
+	struct generic_pm_domain genpd;
+	struct device_node *np;
+	unsigned int num_core_pm_clks;
+	unsigned int core_pm_clks[0];
+};
+
+static bool cpg_mssr_is_pm_clk(const struct of_phandle_args *clkspec,
+			       struct cpg_mssr_clk_domain *pd)
+{
+	unsigned int i;
+
+	if (clkspec->np != pd->np || clkspec->args_count != 2)
+		return false;
+
+	switch (clkspec->args[0]) {
+	case CPG_CORE:
+		for (i = 0; i < pd->num_core_pm_clks; i++)
+			if (clkspec->args[1] == pd->core_pm_clks[i])
+				return true;
+		return false;
+
+	case CPG_MOD:
+		return true;
+
+	default:
+		return false;
+	}
+}
+
+static int cpg_mssr_attach_dev(struct generic_pm_domain *genpd,
+			       struct device *dev)
+{
+	struct cpg_mssr_clk_domain *pd =
+		container_of(genpd, struct cpg_mssr_clk_domain, genpd);
+	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 (cpg_mssr_is_pm_clk(&clkspec, pd))
+			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;
+}
+
+static void cpg_mssr_detach_dev(struct generic_pm_domain *genpd,
+				struct device *dev)
+{
+	if (!list_empty(&dev->power.subsys_data->clock_list))
+		pm_clk_destroy(dev);
+}
+
+static int __init cpg_mssr_add_clk_domain(struct device *dev,
+					  const unsigned int *core_pm_clks,
+					  unsigned int num_core_pm_clks)
+{
+	struct device_node *np = dev->of_node;
+	struct generic_pm_domain *genpd;
+	struct cpg_mssr_clk_domain *pd;
+	size_t pm_size = num_core_pm_clks * sizeof(core_pm_clks[0]);
+
+	pd = devm_kzalloc(dev, sizeof(*pd) + pm_size, GFP_KERNEL);
+	if (!pd)
+		return -ENOMEM;
+
+	pd->np = np;
+	pd->num_core_pm_clks = num_core_pm_clks;
+	memcpy(pd->core_pm_clks, core_pm_clks, pm_size);
+
+	genpd = &pd->genpd;
+	genpd->name = np->name;
+	genpd->flags = GENPD_FLAG_PM_CLK;
+	pm_genpd_init(genpd, &simple_qos_governor, false);
+	genpd->attach_dev = cpg_mssr_attach_dev;
+	genpd->detach_dev = cpg_mssr_detach_dev;
+
+	of_genpd_add_provider_simple(np, genpd);
+	return 0;
+}
+#else
+static inline int cpg_mssr_add_clk_domain(struct device *dev,
+					  const unsigned int *core_pm_clks,
+					  unsigned int num_core_pm_clks)
+{
+	return 0;
+}
+#endif /* !CONFIG_PM_GENERIC_DOMAINS_OF */
+
+
+static const struct of_device_id cpg_mssr_match[] = {
+#ifdef CONFIG_ARCH_R8A7795
+	{
+		.compatible = "renesas,r8a7795-cpg-mssr",
+		.data = &r8a7795_cpg_mssr_info,
+	},
+#endif
+	{ /* sentinel */ }
+};
+
+static void cpg_mssr_del_clk_provider(void *data)
+{
+	of_clk_del_provider(data);
+}
+
+static int __init cpg_mssr_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	const struct cpg_mssr_info *info;
+	struct cpg_mssr_priv *priv;
+	unsigned int nclks, i;
+	struct resource *res;
+	struct clk **clks;
+	int error;
+
+	info = of_match_node(cpg_mssr_match, np)->data;
+	if (info->init) {
+		error = info->init(dev);
+		if (error)
+			return error;
+	}
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = dev;
+	spin_lock_init(&priv->mstp_lock);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(priv->base))
+		return PTR_ERR(priv->base);
+
+	nclks = info->num_total_core_clks + info->num_hw_mod_clks;
+	clks = devm_kmalloc_array(dev, nclks, sizeof(*clks), GFP_KERNEL);
+	if (!clks)
+		return -ENOMEM;
+
+	priv->clks = clks;
+	priv->num_core_clks = info->num_total_core_clks;
+	priv->num_mod_clks = info->num_hw_mod_clks;
+	priv->last_dt_core_clk = info->last_dt_core_clk;
+
+	for (i = 0; i < nclks; i++)
+		clks[i] = ERR_PTR(-ENOENT);
+
+	for (i = 0; i < info->num_core_clks; i++)
+		cpg_mssr_register_core_clk(&info->core_clks[i], info, priv);
+
+	for (i = 0; i < info->num_mod_clks; i++)
+		cpg_mssr_register_mod_clk(&info->mod_clks[i], info, priv);
+
+	error = of_clk_add_provider(np, cpg_mssr_clk_src_twocell_get, priv);
+	if (error)
+		return error;
+
+	devm_add_action(dev, cpg_mssr_del_clk_provider, np);
+
+	error = cpg_mssr_add_clk_domain(dev, info->core_pm_clks,
+					info->num_core_pm_clks);
+	if (error)
+		return error;
+
+	return 0;
+}
+
+static struct platform_driver cpg_mssr_driver = {
+	.driver		= {
+		.name	= "renesas-cpg-mssr",
+		.of_match_table = cpg_mssr_match,
+	},
+};
+
+static int __init cpg_mssr_init(void)
+{
+	return platform_driver_probe(&cpg_mssr_driver, cpg_mssr_probe);
+}
+
+subsys_initcall(cpg_mssr_init);
+
+MODULE_DESCRIPTION("Renesas CPG/MSSR Driver");
+MODULE_LICENSE("GPL v2");