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path: root/drivers/clk/samsung/clk.c
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Diffstat (limited to 'drivers/clk/samsung/clk.c')
-rw-r--r--drivers/clk/samsung/clk.c314
1 files changed, 314 insertions, 0 deletions
diff --git a/drivers/clk/samsung/clk.c b/drivers/clk/samsung/clk.c
new file mode 100644
index 00000000000..49629c71c9e
--- /dev/null
+++ b/drivers/clk/samsung/clk.c
@@ -0,0 +1,314 @@
+/*
+ * 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/syscore_ops.h>
+#include "clk.h"
+
+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 ret;
+ 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);
+
+ if (!np)
+ return ctx;
+
+ ret = of_clk_add_provider(np, of_clk_src_onecell_get,
+ &ctx->clk_data);
+ if (ret)
+ panic("could not register clock provide\n");
+
+ return ctx;
+}
+
+/* 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
+ */
+#ifdef CONFIG_OF
+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,
+ 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);
+}
+#endif
+
+/* 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);
+}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 13:04:32 +0000