1 files changed, 151 insertions, 0 deletions
diff --git a/drivers/clk/mmp/clk-apbc.c b/drivers/clk/mmp/clk-apbc.c
new file mode 100644
index 000000000..fb294ada0
--- /dev/null
+++ b/drivers/clk/mmp/clk-apbc.c
@@ -0,0 +1,151 @@
+/*
+ * mmp APB clock operation source file
+ *
+ * Copyright (C) 2012 Marvell
+ * Chao Xie <xiechao.mail@gmail.com>
+ *
+ * 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/io.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+
+#include "clk.h"
+
+/* Common APB clock register bit definitions */
+#define APBC_APBCLK	(1 << 0)  /* APB Bus Clock Enable */
+#define APBC_FNCLK	(1 << 1)  /* Functional Clock Enable */
+#define APBC_RST	(1 << 2)  /* Reset Generation */
+#define APBC_POWER	(1 << 7)  /* Reset Generation */
+
+#define to_clk_apbc(hw) container_of(hw, struct clk_apbc, hw)
+struct clk_apbc {
+	struct clk_hw		hw;
+	void __iomem		*base;
+	unsigned int		delay;
+	unsigned int		flags;
+	spinlock_t		*lock;
+};
+
+static int clk_apbc_prepare(struct clk_hw *hw)
+{
+	struct clk_apbc *apbc = to_clk_apbc(hw);
+	unsigned int data;
+	unsigned long flags = 0;
+
+	/*
+	 * It may share same register as MUX clock,
+	 * and it will impact FNCLK enable. Spinlock is needed
+	 */
+	if (apbc->lock)
+		spin_lock_irqsave(apbc->lock, flags);
+
+	data = readl_relaxed(apbc->base);
+	if (apbc->flags & APBC_POWER_CTRL)
+		data |= APBC_POWER;
+	data |= APBC_FNCLK;
+	writel_relaxed(data, apbc->base);
+
+	if (apbc->lock)
+		spin_unlock_irqrestore(apbc->lock, flags);
+
+	udelay(apbc->delay);
+
+	if (apbc->lock)
+		spin_lock_irqsave(apbc->lock, flags);
+
+	data = readl_relaxed(apbc->base);
+	data |= APBC_APBCLK;
+	writel_relaxed(data, apbc->base);
+
+	if (apbc->lock)
+		spin_unlock_irqrestore(apbc->lock, flags);
+
+	udelay(apbc->delay);
+
+	if (!(apbc->flags & APBC_NO_BUS_CTRL)) {
+		if (apbc->lock)
+			spin_lock_irqsave(apbc->lock, flags);
+
+		data = readl_relaxed(apbc->base);
+		data &= ~APBC_RST;
+		writel_relaxed(data, apbc->base);
+
+		if (apbc->lock)
+			spin_unlock_irqrestore(apbc->lock, flags);
+	}
+
+	return 0;
+}
+
+static void clk_apbc_unprepare(struct clk_hw *hw)
+{
+	struct clk_apbc *apbc = to_clk_apbc(hw);
+	unsigned long data;
+	unsigned long flags = 0;
+
+	if (apbc->lock)
+		spin_lock_irqsave(apbc->lock, flags);
+
+	data = readl_relaxed(apbc->base);
+	if (apbc->flags & APBC_POWER_CTRL)
+		data &= ~APBC_POWER;
+	data &= ~APBC_FNCLK;
+	writel_relaxed(data, apbc->base);
+
+	if (apbc->lock)
+		spin_unlock_irqrestore(apbc->lock, flags);
+
+	udelay(10);
+
+	if (apbc->lock)
+		spin_lock_irqsave(apbc->lock, flags);
+
+	data = readl_relaxed(apbc->base);
+	data &= ~APBC_APBCLK;
+	writel_relaxed(data, apbc->base);
+
+	if (apbc->lock)
+		spin_unlock_irqrestore(apbc->lock, flags);
+}
+
+static const struct clk_ops clk_apbc_ops = {
+	.prepare = clk_apbc_prepare,
+	.unprepare = clk_apbc_unprepare,
+};
+
+struct clk *mmp_clk_register_apbc(const char *name, const char *parent_name,
+		void __iomem *base, unsigned int delay,
+		unsigned int apbc_flags, spinlock_t *lock)
+{
+	struct clk_apbc *apbc;
+	struct clk *clk;
+	struct clk_init_data init;
+
+	apbc = kzalloc(sizeof(*apbc), GFP_KERNEL);
+	if (!apbc)
+		return NULL;
+
+	init.name = name;
+	init.ops = &clk_apbc_ops;
+	init.flags = CLK_SET_RATE_PARENT;
+	init.parent_names = (parent_name ? &parent_name : NULL);
+	init.num_parents = (parent_name ? 1 : 0);
+
+	apbc->base = base;
+	apbc->delay = delay;
+	apbc->flags = apbc_flags;
+	apbc->lock = lock;
+	apbc->hw.init = &init;
+
+	clk = clk_register(NULL, &apbc->hw);
+	if (IS_ERR(clk))
+		kfree(apbc);
+
+	return clk;
+}