clk: ux500: Adapt PRCMU and PRCC clocks for common clk

First version of common clock implementation of PRCMU clocks
and PRCC clocks for ux500 platforms.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

1 files changed, 238 insertions, 0 deletions

diff --git a/drivers/clk/ux500/clk-prcmu.c b/drivers/clk/ux500/clk-prcmu.c
new file mode 100644
index 00000000000..1d779ad1216
--- /dev/null
+++ b/drivers/clk/ux500/clk-prcmu.c
@@ -0,0 +1,238 @@
+/*
+ * PRCMU clock implementation for ux500 platform.
+ *
+ * Copyright (C) 2012 ST-Ericsson SA
+ * Author: Ulf Hansson <ulf.hansson@linaro.org>
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clk-private.h>
+#include <linux/mfd/dbx500-prcmu.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include "clk.h"
+
+#define to_clk_prcmu(_hw) container_of(_hw, struct clk_prcmu, hw)
+
+struct clk_prcmu {
+	struct clk_hw hw;
+	u8 cg_sel;
+	int is_enabled;
+};
+
+/* PRCMU clock operations. */
+
+static int clk_prcmu_prepare(struct clk_hw *hw)
+{
+	struct clk_prcmu *clk = to_clk_prcmu(hw);
+	return prcmu_request_clock(clk->cg_sel, true);
+}
+
+static void clk_prcmu_unprepare(struct clk_hw *hw)
+{
+	struct clk_prcmu *clk = to_clk_prcmu(hw);
+	if (prcmu_request_clock(clk->cg_sel, false))
+		pr_err("clk_prcmu: %s failed to disable %s.\n", __func__,
+			hw->init->name);
+}
+
+static int clk_prcmu_enable(struct clk_hw *hw)
+{
+	struct clk_prcmu *clk = to_clk_prcmu(hw);
+	clk->is_enabled = 1;
+	return 0;
+}
+
+static void clk_prcmu_disable(struct clk_hw *hw)
+{
+	struct clk_prcmu *clk = to_clk_prcmu(hw);
+	clk->is_enabled = 0;
+}
+
+static int clk_prcmu_is_enabled(struct clk_hw *hw)
+{
+	struct clk_prcmu *clk = to_clk_prcmu(hw);
+	return clk->is_enabled;
+}
+
+static unsigned long clk_prcmu_recalc_rate(struct clk_hw *hw,
+					   unsigned long parent_rate)
+{
+	struct clk_prcmu *clk = to_clk_prcmu(hw);
+	return prcmu_clock_rate(clk->cg_sel);
+}
+
+static long clk_prcmu_round_rate(struct clk_hw *hw, unsigned long rate,
+				 unsigned long *parent_rate)
+{
+	struct clk_prcmu *clk = to_clk_prcmu(hw);
+	return prcmu_round_clock_rate(clk->cg_sel, rate);
+}
+
+static int clk_prcmu_set_rate(struct clk_hw *hw, unsigned long rate,
+			      unsigned long parent_rate)
+{
+	struct clk_prcmu *clk = to_clk_prcmu(hw);
+	return prcmu_set_clock_rate(clk->cg_sel, rate);
+}
+
+static int request_ape_opp100(bool enable)
+{
+	static int reqs;
+	int err = 0;
+
+	if (enable) {
+		if (!reqs)
+			err = prcmu_qos_add_requirement(PRCMU_QOS_APE_OPP,
+							"clock", 100);
+		if (!err)
+			reqs++;
+	} else {
+		reqs--;
+		if (!reqs)
+			prcmu_qos_remove_requirement(PRCMU_QOS_APE_OPP,
+						"clock");
+	}
+	return err;
+}
+
+static int clk_prcmu_opp_prepare(struct clk_hw *hw)
+{
+	int err;
+	struct clk_prcmu *clk = to_clk_prcmu(hw);
+
+	err = request_ape_opp100(true);
+	if (err) {
+		pr_err("clk_prcmu: %s failed to request APE OPP100 for %s.\n",
+			__func__, hw->init->name);
+		return err;
+	}
+
+	err = prcmu_request_clock(clk->cg_sel, true);
+	if (err)
+		request_ape_opp100(false);
+
+	return err;
+}
+
+static void clk_prcmu_opp_unprepare(struct clk_hw *hw)
+{
+	struct clk_prcmu *clk = to_clk_prcmu(hw);
+
+	if (prcmu_request_clock(clk->cg_sel, false))
+		goto out_error;
+	if (request_ape_opp100(false))
+		goto out_error;
+	return;
+
+out_error:
+	pr_err("clk_prcmu: %s failed to disable %s.\n", __func__,
+		hw->init->name);
+}
+
+static struct clk_ops clk_prcmu_scalable_ops = {
+	.prepare = clk_prcmu_prepare,
+	.unprepare = clk_prcmu_unprepare,
+	.enable = clk_prcmu_enable,
+	.disable = clk_prcmu_disable,
+	.is_enabled = clk_prcmu_is_enabled,
+	.recalc_rate = clk_prcmu_recalc_rate,
+	.round_rate = clk_prcmu_round_rate,
+	.set_rate = clk_prcmu_set_rate,
+};
+
+static struct clk_ops clk_prcmu_gate_ops = {
+	.prepare = clk_prcmu_prepare,
+	.unprepare = clk_prcmu_unprepare,
+	.enable = clk_prcmu_enable,
+	.disable = clk_prcmu_disable,
+	.is_enabled = clk_prcmu_is_enabled,
+	.recalc_rate = clk_prcmu_recalc_rate,
+};
+
+static struct clk_ops clk_prcmu_opp_gate_ops = {
+	.prepare = clk_prcmu_opp_prepare,
+	.unprepare = clk_prcmu_opp_unprepare,
+	.enable = clk_prcmu_enable,
+	.disable = clk_prcmu_disable,
+	.is_enabled = clk_prcmu_is_enabled,
+	.recalc_rate = clk_prcmu_recalc_rate,
+};
+
+static struct clk *clk_reg_prcmu(const char *name,
+				 const char *parent_name,
+				 u8 cg_sel,
+				 unsigned long rate,
+				 unsigned long flags,
+				 struct clk_ops *clk_prcmu_ops)
+{
+	struct clk_prcmu *clk;
+	struct clk_init_data clk_prcmu_init;
+	struct clk *clk_reg;
+
+	if (!name) {
+		pr_err("clk_prcmu: %s invalid arguments passed\n", __func__);
+		return ERR_PTR(-EINVAL);
+	}
+
+	clk = kzalloc(sizeof(struct clk_prcmu), GFP_KERNEL);
+	if (!clk) {
+		pr_err("clk_prcmu: %s could not allocate clk\n", __func__);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	clk->cg_sel = cg_sel;
+	clk->is_enabled = 1;
+	/* "rate" can be used for changing the initial frequency */
+	if (rate)
+		prcmu_set_clock_rate(cg_sel, rate);
+
+	clk_prcmu_init.name = name;
+	clk_prcmu_init.ops = clk_prcmu_ops;
+	clk_prcmu_init.flags = flags;
+	clk_prcmu_init.parent_names = (parent_name ? &parent_name : NULL);
+	clk_prcmu_init.num_parents = (parent_name ? 1 : 0);
+	clk->hw.init = &clk_prcmu_init;
+
+	clk_reg = clk_register(NULL, &clk->hw);
+	if (IS_ERR_OR_NULL(clk_reg))
+		goto free_clk;
+
+	return clk_reg;
+
+free_clk:
+	kfree(clk);
+	pr_err("clk_prcmu: %s failed to register clk\n", __func__);
+	return ERR_PTR(-ENOMEM);
+}
+
+struct clk *clk_reg_prcmu_scalable(const char *name,
+				   const char *parent_name,
+				   u8 cg_sel,
+				   unsigned long rate,
+				   unsigned long flags)
+{
+	return clk_reg_prcmu(name, parent_name, cg_sel, rate, flags,
+			&clk_prcmu_scalable_ops);
+}
+
+struct clk *clk_reg_prcmu_gate(const char *name,
+			       const char *parent_name,
+			       u8 cg_sel,
+			       unsigned long flags)
+{
+	return clk_reg_prcmu(name, parent_name, cg_sel, 0, flags,
+			&clk_prcmu_gate_ops);
+}
+
+struct clk *clk_reg_prcmu_opp_gate(const char *name,
+				   const char *parent_name,
+				   u8 cg_sel,
+				   unsigned long flags)
+{
+	return clk_reg_prcmu(name, parent_name, cg_sel, 0, flags,
+			&clk_prcmu_opp_gate_ops);
+}