clk: mvebu: add common clock functions for core clk and clk gating

Based on the current common functions for core clocks and clock
gating control, new common functions are joined in a single file.
Given the opportunity, names of functions and structs are unified,
and also a Kconfig entry is added.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

4 files changed, 215 insertions, 0 deletions

diff --git a/drivers/clk/mvebu/Kconfig b/drivers/clk/mvebu/Kconfig
index 57323fd15ec9..2c3cf9571ce5 100644
--- a/drivers/clk/mvebu/Kconfig
+++ b/drivers/clk/mvebu/Kconfig
@@ -6,3 +6,6 @@ config MVEBU_CLK_CPU
 
 config MVEBU_CLK_GATING
        bool
+
+config MVEBU_CLK_COMMON
+        bool
diff --git a/drivers/clk/mvebu/Makefile b/drivers/clk/mvebu/Makefile
index 58df3dc49363..21432303bb3e 100644
--- a/drivers/clk/mvebu/Makefile
+++ b/drivers/clk/mvebu/Makefile
@@ -1,3 +1,4 @@
+obj-$(CONFIG_MVEBU_CLK_COMMON)  += common.o
 obj-$(CONFIG_MVEBU_CLK_CORE)    += clk.o clk-core.o
 obj-$(CONFIG_MVEBU_CLK_CPU)     += clk-cpu.o
 obj-$(CONFIG_MVEBU_CLK_GATING)  += clk-gating-ctrl.o
diff --git a/drivers/clk/mvebu/common.c b/drivers/clk/mvebu/common.c
new file mode 100644
index 000000000000..adaa4a1821b8
--- /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);
+}
diff --git a/drivers/clk/mvebu/common.h b/drivers/clk/mvebu/common.h
new file mode 100644
index 000000000000..f968b4d9df92
--- /dev/null
+++ b/drivers/clk/mvebu/common.h
@@ -0,0 +1,48 @@
+/*
+ * 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.
+ */
+
+#ifndef __CLK_MVEBU_COMMON_H_
+#define __CLK_MVEBU_COMMON_H_
+
+#include <linux/kernel.h>
+
+struct device_node;
+
+struct coreclk_ratio {
+        int id;
+        const char *name;
+};
+
+struct coreclk_soc_desc {
+        u32 (*get_tclk_freq)(void __iomem *sar);
+        u32 (*get_cpu_freq)(void __iomem *sar);
+        void (*get_clk_ratio)(void __iomem *sar, int id, int *mult, int *div);
+        const struct coreclk_ratio *ratios;
+        int num_ratios;
+};
+
+struct clk_gating_soc_desc {
+        const char *name;
+        const char *parent;
+        int bit_idx;
+        unsigned long flags;
+};
+
+void __init mvebu_coreclk_setup(struct device_node *np,
+                                const struct coreclk_soc_desc *desc);
+
+void __init mvebu_clk_gating_setup(struct device_node *np,
+                                   const struct clk_gating_soc_desc *desc);
+
+#endif