Linux-libre 4.2-gnu

1 files changed, 156 insertions, 0 deletions

diff --git a/drivers/clk/hisilicon/clkdivider-hi6220.c b/drivers/clk/hisilicon/clkdivider-hi6220.c
new file mode 100644
index 000000000..113eee8ed
--- /dev/null
+++ b/drivers/clk/hisilicon/clkdivider-hi6220.c
@@ -0,0 +1,156 @@
+/*
+ * Hisilicon hi6220 SoC divider clock driver
+ *
+ * Copyright (c) 2015 Hisilicon Limited.
+ *
+ * Author: Bintian Wang <bintian.wang@huawei.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/spinlock.h>
+
+#define div_mask(width)	((1 << (width)) - 1)
+
+/**
+ * struct hi6220_clk_divider - divider clock for hi6220
+ *
+ * @hw:		handle between common and hardware-specific interfaces
+ * @reg:	register containing divider
+ * @shift:	shift to the divider bit field
+ * @width:	width of the divider bit field
+ * @mask:	mask for setting divider rate
+ * @table:	the div table that the divider supports
+ * @lock:	register lock
+ */
+struct hi6220_clk_divider {
+	struct clk_hw	hw;
+	void __iomem	*reg;
+	u8		shift;
+	u8		width;
+	u32		mask;
+	const struct clk_div_table *table;
+	spinlock_t	*lock;
+};
+
+#define to_hi6220_clk_divider(_hw)	\
+	container_of(_hw, struct hi6220_clk_divider, hw)
+
+static unsigned long hi6220_clkdiv_recalc_rate(struct clk_hw *hw,
+					unsigned long parent_rate)
+{
+	unsigned int val;
+	struct hi6220_clk_divider *dclk = to_hi6220_clk_divider(hw);
+
+	val = readl_relaxed(dclk->reg) >> dclk->shift;
+	val &= div_mask(dclk->width);
+
+	return divider_recalc_rate(hw, parent_rate, val, dclk->table,
+				   CLK_DIVIDER_ROUND_CLOSEST);
+}
+
+static long hi6220_clkdiv_round_rate(struct clk_hw *hw, unsigned long rate,
+					unsigned long *prate)
+{
+	struct hi6220_clk_divider *dclk = to_hi6220_clk_divider(hw);
+
+	return divider_round_rate(hw, rate, prate, dclk->table,
+				  dclk->width, CLK_DIVIDER_ROUND_CLOSEST);
+}
+
+static int hi6220_clkdiv_set_rate(struct clk_hw *hw, unsigned long rate,
+					unsigned long parent_rate)
+{
+	int value;
+	unsigned long flags = 0;
+	u32 data;
+	struct hi6220_clk_divider *dclk = to_hi6220_clk_divider(hw);
+
+	value = divider_get_val(rate, parent_rate, dclk->table,
+				dclk->width, CLK_DIVIDER_ROUND_CLOSEST);
+
+	if (dclk->lock)
+		spin_lock_irqsave(dclk->lock, flags);
+
+	data = readl_relaxed(dclk->reg);
+	data &= ~(div_mask(dclk->width) << dclk->shift);
+	data |= value << dclk->shift;
+	data |= dclk->mask;
+
+	writel_relaxed(data, dclk->reg);
+
+	if (dclk->lock)
+		spin_unlock_irqrestore(dclk->lock, flags);
+
+	return 0;
+}
+
+static const struct clk_ops hi6220_clkdiv_ops = {
+	.recalc_rate = hi6220_clkdiv_recalc_rate,
+	.round_rate = hi6220_clkdiv_round_rate,
+	.set_rate = hi6220_clkdiv_set_rate,
+};
+
+struct clk *hi6220_register_clkdiv(struct device *dev, const char *name,
+	const char *parent_name, unsigned long flags, void __iomem *reg,
+	u8 shift, u8 width, u32 mask_bit, spinlock_t *lock)
+{
+	struct hi6220_clk_divider *div;
+	struct clk *clk;
+	struct clk_init_data init;
+	struct clk_div_table *table;
+	u32 max_div, min_div;
+	int i;
+
+	/* allocate the divider */
+	div = kzalloc(sizeof(*div), GFP_KERNEL);
+	if (!div)
+		return ERR_PTR(-ENOMEM);
+
+	/* Init the divider table */
+	max_div = div_mask(width) + 1;
+	min_div = 1;
+
+	table = kcalloc(max_div + 1, sizeof(*table), GFP_KERNEL);
+	if (!table) {
+		kfree(div);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	for (i = 0; i < max_div; i++) {
+		table[i].div = min_div + i;
+		table[i].val = table[i].div - 1;
+	}
+
+	init.name = name;
+	init.ops = &hi6220_clkdiv_ops;
+	init.flags = flags;
+	init.parent_names = parent_name ? &parent_name : NULL;
+	init.num_parents = parent_name ? 1 : 0;
+
+	/* struct hi6220_clk_divider assignments */
+	div->reg = reg;
+	div->shift = shift;
+	div->width = width;
+	div->mask = mask_bit ? BIT(mask_bit) : 0;
+	div->lock = lock;
+	div->hw.init = &init;
+	div->table = table;
+
+	/* register the clock */
+	clk = clk_register(dev, &div->hw);
+	if (IS_ERR(clk)) {
+		kfree(table);
+		kfree(div);
+	}
+
+	return clk;
+}