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path: root/drivers/clk/ux500/clk-prcmu.c
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-rw-r--r--drivers/clk/ux500/clk-prcmu.c252
1 files changed, 252 insertions, 0 deletions
diff --git a/drivers/clk/ux500/clk-prcmu.c b/drivers/clk/ux500/clk-prcmu.c
new file mode 100644
index 000000000000..930cdfeb47ab
--- /dev/null
+++ b/drivers/clk/ux500/clk-prcmu.c
@@ -0,0 +1,252 @@
+/*
+ * 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_rate_ops = {
+ .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_rate(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_rate_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);
+}