1 files changed, 108 insertions, 0 deletions
diff --git a/drivers/clk/imx/clk-cpu.c b/drivers/clk/imx/clk-cpu.c
new file mode 100644
index 000000000..cb6ca4cf0
--- /dev/null
+++ b/drivers/clk/imx/clk-cpu.c
@@ -0,0 +1,108 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2014 Lucas Stach <l.stach@pengutronix.de>, Pengutronix
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include "clk.h"
+
+struct clk_cpu {
+	struct clk_hw	hw;
+	struct clk	*div;
+	struct clk	*mux;
+	struct clk	*pll;
+	struct clk	*step;
+};
+
+static inline struct clk_cpu *to_clk_cpu(struct clk_hw *hw)
+{
+	return container_of(hw, struct clk_cpu, hw);
+}
+
+static unsigned long clk_cpu_recalc_rate(struct clk_hw *hw,
+					 unsigned long parent_rate)
+{
+	struct clk_cpu *cpu = to_clk_cpu(hw);
+
+	return clk_get_rate(cpu->div);
+}
+
+static long clk_cpu_round_rate(struct clk_hw *hw, unsigned long rate,
+			       unsigned long *prate)
+{
+	struct clk_cpu *cpu = to_clk_cpu(hw);
+
+	return clk_round_rate(cpu->pll, rate);
+}
+
+static int clk_cpu_set_rate(struct clk_hw *hw, unsigned long rate,
+			    unsigned long parent_rate)
+{
+	struct clk_cpu *cpu = to_clk_cpu(hw);
+	int ret;
+
+	/* switch to PLL bypass clock */
+	ret = clk_set_parent(cpu->mux, cpu->step);
+	if (ret)
+		return ret;
+
+	/* reprogram PLL */
+	ret = clk_set_rate(cpu->pll, rate);
+	if (ret) {
+		clk_set_parent(cpu->mux, cpu->pll);
+		return ret;
+	}
+	/* switch back to PLL clock */
+	clk_set_parent(cpu->mux, cpu->pll);
+
+	/* Ensure the divider is what we expect */
+	clk_set_rate(cpu->div, rate);
+
+	return 0;
+}
+
+static const struct clk_ops clk_cpu_ops = {
+	.recalc_rate	= clk_cpu_recalc_rate,
+	.round_rate	= clk_cpu_round_rate,
+	.set_rate	= clk_cpu_set_rate,
+};
+
+struct clk_hw *imx_clk_hw_cpu(const char *name, const char *parent_name,
+		struct clk *div, struct clk *mux, struct clk *pll,
+		struct clk *step)
+{
+	struct clk_cpu *cpu;
+	struct clk_hw *hw;
+	struct clk_init_data init;
+	int ret;
+
+	cpu = kzalloc(sizeof(*cpu), GFP_KERNEL);
+	if (!cpu)
+		return ERR_PTR(-ENOMEM);
+
+	cpu->div = div;
+	cpu->mux = mux;
+	cpu->pll = pll;
+	cpu->step = step;
+
+	init.name = name;
+	init.ops = &clk_cpu_ops;
+	init.flags = CLK_IS_CRITICAL;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+
+	cpu->hw.init = &init;
+	hw = &cpu->hw;
+
+	ret = clk_hw_register(NULL, hw);
+	if (ret) {
+		kfree(cpu);
+		return ERR_PTR(ret);
+	}
+
+	return hw;
+}
+EXPORT_SYMBOL_GPL(imx_clk_hw_cpu);