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path: root/drivers/clk/mvebu/common.c
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-rw-r--r--drivers/clk/mvebu/common.c163
1 files changed, 163 insertions, 0 deletions
diff --git a/drivers/clk/mvebu/common.c b/drivers/clk/mvebu/common.c
new file mode 100644
index 0000000..adaa4a1
--- /dev/null
+++ b/drivers/clk/mvebu/common.c
@@ -0,0 +1,163 @@
+/*
+ * Marvell EBU SoC common clock handling
+ *
+ * Copyright (C) 2012 Marvell
+ *
+ * Gregory CLEMENT <gregory.clement@free-electrons.com>
+ * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
+ * Andrew Lunn <andrew@lunn.ch>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#include "common.h"
+
+/*
+ * Core Clocks
+ */
+
+static struct clk_onecell_data clk_data;
+
+void __init mvebu_coreclk_setup(struct device_node *np,
+ const struct coreclk_soc_desc *desc)
+{
+ const char *tclk_name = "tclk";
+ const char *cpuclk_name = "cpuclk";
+ void __iomem *base;
+ unsigned long rate;
+ int n;
+
+ base = of_iomap(np, 0);
+ if (WARN_ON(!base))
+ return;
+
+ /* Allocate struct for TCLK, cpu clk, and core ratio clocks */
+ clk_data.clk_num = 2 + desc->num_ratios;
+ clk_data.clks = kzalloc(clk_data.clk_num * sizeof(struct clk *),
+ GFP_KERNEL);
+ if (WARN_ON(!clk_data.clks))
+ return;
+
+ /* Register TCLK */
+ of_property_read_string_index(np, "clock-output-names", 0,
+ &tclk_name);
+ rate = desc->get_tclk_freq(base);
+ clk_data.clks[0] = clk_register_fixed_rate(NULL, tclk_name, NULL,
+ CLK_IS_ROOT, rate);
+ WARN_ON(IS_ERR(clk_data.clks[0]));
+
+ /* Register CPU clock */
+ of_property_read_string_index(np, "clock-output-names", 1,
+ &cpuclk_name);
+ rate = desc->get_cpu_freq(base);
+ clk_data.clks[1] = clk_register_fixed_rate(NULL, cpuclk_name, NULL,
+ CLK_IS_ROOT, rate);
+ WARN_ON(IS_ERR(clk_data.clks[1]));
+
+ /* Register fixed-factor clocks derived from CPU clock */
+ for (n = 0; n < desc->num_ratios; n++) {
+ const char *rclk_name = desc->ratios[n].name;
+ int mult, div;
+
+ of_property_read_string_index(np, "clock-output-names",
+ 2+n, &rclk_name);
+ desc->get_clk_ratio(base, desc->ratios[n].id, &mult, &div);
+ clk_data.clks[2+n] = clk_register_fixed_factor(NULL, rclk_name,
+ cpuclk_name, 0, mult, div);
+ WARN_ON(IS_ERR(clk_data.clks[2+n]));
+ };
+
+ /* SAR register isn't needed anymore */
+ iounmap(base);
+
+ of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
+}
+
+/*
+ * Clock Gating Control
+ */
+
+struct clk_gating_ctrl {
+ spinlock_t lock;
+ struct clk **gates;
+ int num_gates;
+};
+
+#define to_clk_gate(_hw) container_of(_hw, struct clk_gate, hw)
+
+static struct clk *clk_gating_get_src(
+ struct of_phandle_args *clkspec, void *data)
+{
+ struct clk_gating_ctrl *ctrl = (struct clk_gating_ctrl *)data;
+ int n;
+
+ if (clkspec->args_count < 1)
+ return ERR_PTR(-EINVAL);
+
+ for (n = 0; n < ctrl->num_gates; n++) {
+ struct clk_gate *gate =
+ to_clk_gate(__clk_get_hw(ctrl->gates[n]));
+ if (clkspec->args[0] == gate->bit_idx)
+ return ctrl->gates[n];
+ }
+ return ERR_PTR(-ENODEV);
+}
+
+void __init mvebu_clk_gating_setup(struct device_node *np,
+ const struct clk_gating_soc_desc *desc)
+{
+ struct clk_gating_ctrl *ctrl;
+ struct clk *clk;
+ void __iomem *base;
+ const char *default_parent = NULL;
+ int n;
+
+ base = of_iomap(np, 0);
+ if (WARN_ON(!base))
+ return;
+
+ clk = of_clk_get(np, 0);
+ if (!IS_ERR(clk)) {
+ default_parent = __clk_get_name(clk);
+ clk_put(clk);
+ }
+
+ ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
+ if (WARN_ON(!ctrl))
+ return;
+
+ spin_lock_init(&ctrl->lock);
+
+ /* Count, allocate, and register clock gates */
+ for (n = 0; desc[n].name;)
+ n++;
+
+ ctrl->num_gates = n;
+ ctrl->gates = kzalloc(ctrl->num_gates * sizeof(struct clk *),
+ GFP_KERNEL);
+ if (WARN_ON(!ctrl->gates)) {
+ kfree(ctrl);
+ return;
+ }
+
+ for (n = 0; n < ctrl->num_gates; n++) {
+ const char *parent =
+ (desc[n].parent) ? desc[n].parent : default_parent;
+ ctrl->gates[n] = clk_register_gate(NULL, desc[n].name, parent,
+ desc[n].flags, base, desc[n].bit_idx,
+ 0, &ctrl->lock);
+ WARN_ON(IS_ERR(ctrl->gates[n]));
+ }
+
+ of_clk_add_provider(np, clk_gating_get_src, ctrl);
+}