Initial import

1 files changed, 420 insertions, 0 deletions

diff --git a/drivers/clk/samsung/clk.c b/drivers/clk/samsung/clk.c
new file mode 100644
index 000000000..9e1f88c04
--- /dev/null
+++ b/drivers/clk/samsung/clk.c
@@ -0,0 +1,420 @@
+/*
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ * Copyright (c) 2013 Linaro Ltd.
+ * Author: Thomas Abraham <thomas.ab@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This file includes utility functions to register clocks to common
+ * clock framework for Samsung platforms.
+*/
+
+#include <linux/of_address.h>
+#include <linux/syscore_ops.h>
+
+#include "clk.h"
+
+static LIST_HEAD(clock_reg_cache_list);
+
+void samsung_clk_save(void __iomem *base,
+				    struct samsung_clk_reg_dump *rd,
+				    unsigned int num_regs)
+{
+	for (; num_regs > 0; --num_regs, ++rd)
+		rd->value = readl(base + rd->offset);
+}
+
+void samsung_clk_restore(void __iomem *base,
+				      const struct samsung_clk_reg_dump *rd,
+				      unsigned int num_regs)
+{
+	for (; num_regs > 0; --num_regs, ++rd)
+		writel(rd->value, base + rd->offset);
+}
+
+struct samsung_clk_reg_dump *samsung_clk_alloc_reg_dump(
+						const unsigned long *rdump,
+						unsigned long nr_rdump)
+{
+	struct samsung_clk_reg_dump *rd;
+	unsigned int i;
+
+	rd = kcalloc(nr_rdump, sizeof(*rd), GFP_KERNEL);
+	if (!rd)
+		return NULL;
+
+	for (i = 0; i < nr_rdump; ++i)
+		rd[i].offset = rdump[i];
+
+	return rd;
+}
+
+/* setup the essentials required to support clock lookup using ccf */
+struct samsung_clk_provider *__init samsung_clk_init(struct device_node *np,
+			void __iomem *base, unsigned long nr_clks)
+{
+	struct samsung_clk_provider *ctx;
+	struct clk **clk_table;
+	int i;
+
+	ctx = kzalloc(sizeof(struct samsung_clk_provider), GFP_KERNEL);
+	if (!ctx)
+		panic("could not allocate clock provider context.\n");
+
+	clk_table = kcalloc(nr_clks, sizeof(struct clk *), GFP_KERNEL);
+	if (!clk_table)
+		panic("could not allocate clock lookup table\n");
+
+	for (i = 0; i < nr_clks; ++i)
+		clk_table[i] = ERR_PTR(-ENOENT);
+
+	ctx->reg_base = base;
+	ctx->clk_data.clks = clk_table;
+	ctx->clk_data.clk_num = nr_clks;
+	spin_lock_init(&ctx->lock);
+
+	return ctx;
+}
+
+void __init samsung_clk_of_add_provider(struct device_node *np,
+				struct samsung_clk_provider *ctx)
+{
+	if (np) {
+		if (of_clk_add_provider(np, of_clk_src_onecell_get,
+					&ctx->clk_data))
+			panic("could not register clk provider\n");
+	}
+}
+
+/* add a clock instance to the clock lookup table used for dt based lookup */
+void samsung_clk_add_lookup(struct samsung_clk_provider *ctx, struct clk *clk,
+				unsigned int id)
+{
+	if (ctx->clk_data.clks && id)
+		ctx->clk_data.clks[id] = clk;
+}
+
+/* register a list of aliases */
+void __init samsung_clk_register_alias(struct samsung_clk_provider *ctx,
+				struct samsung_clock_alias *list,
+				unsigned int nr_clk)
+{
+	struct clk *clk;
+	unsigned int idx, ret;
+
+	if (!ctx->clk_data.clks) {
+		pr_err("%s: clock table missing\n", __func__);
+		return;
+	}
+
+	for (idx = 0; idx < nr_clk; idx++, list++) {
+		if (!list->id) {
+			pr_err("%s: clock id missing for index %d\n", __func__,
+				idx);
+			continue;
+		}
+
+		clk = ctx->clk_data.clks[list->id];
+		if (!clk) {
+			pr_err("%s: failed to find clock %d\n", __func__,
+				list->id);
+			continue;
+		}
+
+		ret = clk_register_clkdev(clk, list->alias, list->dev_name);
+		if (ret)
+			pr_err("%s: failed to register lookup %s\n",
+					__func__, list->alias);
+	}
+}
+
+/* register a list of fixed clocks */
+void __init samsung_clk_register_fixed_rate(struct samsung_clk_provider *ctx,
+		struct samsung_fixed_rate_clock *list, unsigned int nr_clk)
+{
+	struct clk *clk;
+	unsigned int idx, ret;
+
+	for (idx = 0; idx < nr_clk; idx++, list++) {
+		clk = clk_register_fixed_rate(NULL, list->name,
+			list->parent_name, list->flags, list->fixed_rate);
+		if (IS_ERR(clk)) {
+			pr_err("%s: failed to register clock %s\n", __func__,
+				list->name);
+			continue;
+		}
+
+		samsung_clk_add_lookup(ctx, clk, list->id);
+
+		/*
+		 * Unconditionally add a clock lookup for the fixed rate clocks.
+		 * There are not many of these on any of Samsung platforms.
+		 */
+		ret = clk_register_clkdev(clk, list->name, NULL);
+		if (ret)
+			pr_err("%s: failed to register clock lookup for %s",
+				__func__, list->name);
+	}
+}
+
+/* register a list of fixed factor clocks */
+void __init samsung_clk_register_fixed_factor(struct samsung_clk_provider *ctx,
+		struct samsung_fixed_factor_clock *list, unsigned int nr_clk)
+{
+	struct clk *clk;
+	unsigned int idx;
+
+	for (idx = 0; idx < nr_clk; idx++, list++) {
+		clk = clk_register_fixed_factor(NULL, list->name,
+			list->parent_name, list->flags, list->mult, list->div);
+		if (IS_ERR(clk)) {
+			pr_err("%s: failed to register clock %s\n", __func__,
+				list->name);
+			continue;
+		}
+
+		samsung_clk_add_lookup(ctx, clk, list->id);
+	}
+}
+
+/* register a list of mux clocks */
+void __init samsung_clk_register_mux(struct samsung_clk_provider *ctx,
+				struct samsung_mux_clock *list,
+				unsigned int nr_clk)
+{
+	struct clk *clk;
+	unsigned int idx, ret;
+
+	for (idx = 0; idx < nr_clk; idx++, list++) {
+		clk = clk_register_mux(NULL, list->name, list->parent_names,
+			list->num_parents, list->flags,
+			ctx->reg_base + list->offset,
+			list->shift, list->width, list->mux_flags, &ctx->lock);
+		if (IS_ERR(clk)) {
+			pr_err("%s: failed to register clock %s\n", __func__,
+				list->name);
+			continue;
+		}
+
+		samsung_clk_add_lookup(ctx, clk, list->id);
+
+		/* register a clock lookup only if a clock alias is specified */
+		if (list->alias) {
+			ret = clk_register_clkdev(clk, list->alias,
+						list->dev_name);
+			if (ret)
+				pr_err("%s: failed to register lookup %s\n",
+						__func__, list->alias);
+		}
+	}
+}
+
+/* register a list of div clocks */
+void __init samsung_clk_register_div(struct samsung_clk_provider *ctx,
+				struct samsung_div_clock *list,
+				unsigned int nr_clk)
+{
+	struct clk *clk;
+	unsigned int idx, ret;
+
+	for (idx = 0; idx < nr_clk; idx++, list++) {
+		if (list->table)
+			clk = clk_register_divider_table(NULL, list->name,
+				list->parent_name, list->flags,
+				ctx->reg_base + list->offset,
+				list->shift, list->width, list->div_flags,
+				list->table, &ctx->lock);
+		else
+			clk = clk_register_divider(NULL, list->name,
+				list->parent_name, list->flags,
+				ctx->reg_base + list->offset, list->shift,
+				list->width, list->div_flags, &ctx->lock);
+		if (IS_ERR(clk)) {
+			pr_err("%s: failed to register clock %s\n", __func__,
+				list->name);
+			continue;
+		}
+
+		samsung_clk_add_lookup(ctx, clk, list->id);
+
+		/* register a clock lookup only if a clock alias is specified */
+		if (list->alias) {
+			ret = clk_register_clkdev(clk, list->alias,
+						list->dev_name);
+			if (ret)
+				pr_err("%s: failed to register lookup %s\n",
+						__func__, list->alias);
+		}
+	}
+}
+
+/* register a list of gate clocks */
+void __init samsung_clk_register_gate(struct samsung_clk_provider *ctx,
+				struct samsung_gate_clock *list,
+				unsigned int nr_clk)
+{
+	struct clk *clk;
+	unsigned int idx, ret;
+
+	for (idx = 0; idx < nr_clk; idx++, list++) {
+		clk = clk_register_gate(NULL, list->name, list->parent_name,
+				list->flags, ctx->reg_base + list->offset,
+				list->bit_idx, list->gate_flags, &ctx->lock);
+		if (IS_ERR(clk)) {
+			pr_err("%s: failed to register clock %s\n", __func__,
+				list->name);
+			continue;
+		}
+
+		/* register a clock lookup only if a clock alias is specified */
+		if (list->alias) {
+			ret = clk_register_clkdev(clk, list->alias,
+							list->dev_name);
+			if (ret)
+				pr_err("%s: failed to register lookup %s\n",
+					__func__, list->alias);
+		}
+
+		samsung_clk_add_lookup(ctx, clk, list->id);
+	}
+}
+
+/*
+ * obtain the clock speed of all external fixed clock sources from device
+ * tree and register it
+ */
+void __init samsung_clk_of_register_fixed_ext(struct samsung_clk_provider *ctx,
+			struct samsung_fixed_rate_clock *fixed_rate_clk,
+			unsigned int nr_fixed_rate_clk,
+			const struct of_device_id *clk_matches)
+{
+	const struct of_device_id *match;
+	struct device_node *clk_np;
+	u32 freq;
+
+	for_each_matching_node_and_match(clk_np, clk_matches, &match) {
+		if (of_property_read_u32(clk_np, "clock-frequency", &freq))
+			continue;
+		fixed_rate_clk[(unsigned long)match->data].fixed_rate = freq;
+	}
+	samsung_clk_register_fixed_rate(ctx, fixed_rate_clk, nr_fixed_rate_clk);
+}
+
+/* utility function to get the rate of a specified clock */
+unsigned long _get_rate(const char *clk_name)
+{
+	struct clk *clk;
+
+	clk = __clk_lookup(clk_name);
+	if (!clk) {
+		pr_err("%s: could not find clock %s\n", __func__, clk_name);
+		return 0;
+	}
+
+	return clk_get_rate(clk);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int samsung_clk_suspend(void)
+{
+	struct samsung_clock_reg_cache *reg_cache;
+
+	list_for_each_entry(reg_cache, &clock_reg_cache_list, node)
+		samsung_clk_save(reg_cache->reg_base, reg_cache->rdump,
+				reg_cache->rd_num);
+	return 0;
+}
+
+static void samsung_clk_resume(void)
+{
+	struct samsung_clock_reg_cache *reg_cache;
+
+	list_for_each_entry(reg_cache, &clock_reg_cache_list, node)
+		samsung_clk_restore(reg_cache->reg_base, reg_cache->rdump,
+				reg_cache->rd_num);
+}
+
+static struct syscore_ops samsung_clk_syscore_ops = {
+	.suspend = samsung_clk_suspend,
+	.resume = samsung_clk_resume,
+};
+
+static void samsung_clk_sleep_init(void __iomem *reg_base,
+		const unsigned long *rdump,
+		unsigned long nr_rdump)
+{
+	struct samsung_clock_reg_cache *reg_cache;
+
+	reg_cache = kzalloc(sizeof(struct samsung_clock_reg_cache),
+			GFP_KERNEL);
+	if (!reg_cache)
+		panic("could not allocate register reg_cache.\n");
+	reg_cache->rdump = samsung_clk_alloc_reg_dump(rdump, nr_rdump);
+
+	if (!reg_cache->rdump)
+		panic("could not allocate register dump storage.\n");
+
+	if (list_empty(&clock_reg_cache_list))
+		register_syscore_ops(&samsung_clk_syscore_ops);
+
+	reg_cache->reg_base = reg_base;
+	reg_cache->rd_num = nr_rdump;
+	list_add_tail(&reg_cache->node, &clock_reg_cache_list);
+}
+
+#else
+static void samsung_clk_sleep_init(void __iomem *reg_base,
+		const unsigned long *rdump,
+		unsigned long nr_rdump) {}
+#endif
+
+/*
+ * Common function which registers plls, muxes, dividers and gates
+ * for each CMU. It also add CMU register list to register cache.
+ */
+struct samsung_clk_provider * __init samsung_cmu_register_one(
+			struct device_node *np,
+			struct samsung_cmu_info *cmu)
+{
+	void __iomem *reg_base;
+	struct samsung_clk_provider *ctx;
+
+	reg_base = of_iomap(np, 0);
+	if (!reg_base) {
+		panic("%s: failed to map registers\n", __func__);
+		return NULL;
+	}
+
+	ctx = samsung_clk_init(np, reg_base, cmu->nr_clk_ids);
+	if (!ctx) {
+		panic("%s: unable to alllocate ctx\n", __func__);
+		return ctx;
+	}
+
+	if (cmu->pll_clks)
+		samsung_clk_register_pll(ctx, cmu->pll_clks, cmu->nr_pll_clks,
+			reg_base);
+	if (cmu->mux_clks)
+		samsung_clk_register_mux(ctx, cmu->mux_clks,
+			cmu->nr_mux_clks);
+	if (cmu->div_clks)
+		samsung_clk_register_div(ctx, cmu->div_clks, cmu->nr_div_clks);
+	if (cmu->gate_clks)
+		samsung_clk_register_gate(ctx, cmu->gate_clks,
+			cmu->nr_gate_clks);
+	if (cmu->fixed_clks)
+		samsung_clk_register_fixed_rate(ctx, cmu->fixed_clks,
+			cmu->nr_fixed_clks);
+	if (cmu->fixed_factor_clks)
+		samsung_clk_register_fixed_factor(ctx, cmu->fixed_factor_clks,
+			cmu->nr_fixed_factor_clks);
+	if (cmu->clk_regs)
+		samsung_clk_sleep_init(reg_base, cmu->clk_regs,
+			cmu->nr_clk_regs);
+
+	samsung_clk_of_add_provider(np, ctx);
+
+	return ctx;
+}