[PATCH] clk: add table lookup to mux

Peter De Schrijver pdeschrijver at nvidia.com
Tue Mar 12 14:42:23 EDT 2013


Add a table lookup feature to the mux clock. Also allow arbitrary masks
instead of the width. This will be used by some clocks on Tegra114. Also
adapt the tegra periph clk because it uses struct clk_mux directly.

Signed-off-by: Peter De Schrijver <pdeschrijver at nvidia.com>

--
Mike,

This is the same patch I posted before which implements a table lookup
feature for the mux clock. I squashed both the changes to clk-mux.c and
tegra/clk.h together in order to make the patch bisectable.

Thanks,

Peter.
---
 drivers/clk/clk-mux.c        |   50 ++++++++++++++++++++++++++++++++----------
 drivers/clk/tegra/clk.h      |   27 ++++++++++++++++-------
 include/linux/clk-private.h  |    3 ++-
 include/linux/clk-provider.h |    9 +++++++-
 4 files changed, 68 insertions(+), 21 deletions(-)

diff --git a/drivers/clk/clk-mux.c b/drivers/clk/clk-mux.c
index 508c032..25b1734 100644
--- a/drivers/clk/clk-mux.c
+++ b/drivers/clk/clk-mux.c
@@ -32,6 +32,7 @@
 static u8 clk_mux_get_parent(struct clk_hw *hw)
 {
 	struct clk_mux *mux = to_clk_mux(hw);
+	int num_parents = __clk_get_num_parents(hw->clk);
 	u32 val;
 
 	/*
@@ -42,7 +43,16 @@ static u8 clk_mux_get_parent(struct clk_hw *hw)
 	 * val = 0x4 really means "bit 2, index starts at bit 0"
 	 */
 	val = readl(mux->reg) >> mux->shift;
-	val &= (1 << mux->width) - 1;
+	val &= mux->mask;
+
+	if (mux->table) {
+		int i;
+
+		for (i = 0; i < num_parents; i++)
+			if (mux->table[i] == val)
+				return i;
+		return -EINVAL;
+	}
 
 	if (val && (mux->flags & CLK_MUX_INDEX_BIT))
 		val = ffs(val) - 1;
@@ -50,7 +60,7 @@ static u8 clk_mux_get_parent(struct clk_hw *hw)
 	if (val && (mux->flags & CLK_MUX_INDEX_ONE))
 		val--;
 
-	if (val >= __clk_get_num_parents(hw->clk))
+	if (val >= num_parents)
 		return -EINVAL;
 
 	return val;
@@ -62,17 +72,22 @@ static int clk_mux_set_parent(struct clk_hw *hw, u8 index)
 	u32 val;
 	unsigned long flags = 0;
 
-	if (mux->flags & CLK_MUX_INDEX_BIT)
-		index = (1 << ffs(index));
+	if (mux->table)
+		index = mux->table[index];
 
-	if (mux->flags & CLK_MUX_INDEX_ONE)
-		index++;
+	else {
+		if (mux->flags & CLK_MUX_INDEX_BIT)
+			index = (1 << ffs(index));
+
+		if (mux->flags & CLK_MUX_INDEX_ONE)
+			index++;
+	}
 
 	if (mux->lock)
 		spin_lock_irqsave(mux->lock, flags);
 
 	val = readl(mux->reg);
-	val &= ~(((1 << mux->width) - 1) << mux->shift);
+	val &= ~(mux->mask << mux->shift);
 	val |= index << mux->shift;
 	writel(val, mux->reg);
 
@@ -88,10 +103,10 @@ const struct clk_ops clk_mux_ops = {
 };
 EXPORT_SYMBOL_GPL(clk_mux_ops);
 
-struct clk *clk_register_mux(struct device *dev, const char *name,
+struct clk *clk_register_mux_table(struct device *dev, const char *name,
 		const char **parent_names, u8 num_parents, unsigned long flags,
-		void __iomem *reg, u8 shift, u8 width,
-		u8 clk_mux_flags, spinlock_t *lock)
+		void __iomem *reg, u8 shift, u32 mask,
+		u8 clk_mux_flags, u32 *table, spinlock_t *lock)
 {
 	struct clk_mux *mux;
 	struct clk *clk;
@@ -113,9 +128,10 @@ struct clk *clk_register_mux(struct device *dev, const char *name,
 	/* struct clk_mux assignments */
 	mux->reg = reg;
 	mux->shift = shift;
-	mux->width = width;
+	mux->mask = mask;
 	mux->flags = clk_mux_flags;
 	mux->lock = lock;
+	mux->table = table;
 	mux->hw.init = &init;
 
 	clk = clk_register(dev, &mux->hw);
@@ -125,3 +141,15 @@ struct clk *clk_register_mux(struct device *dev, const char *name,
 
 	return clk;
 }
+
+struct clk *clk_register_mux(struct device *dev, const char *name,
+		const char **parent_names, u8 num_parents, unsigned long flags,
+		void __iomem *reg, u8 shift, u8 width,
+		u8 clk_mux_flags, spinlock_t *lock)
+{
+	u32 mask = BIT(width) - 1;
+
+	return clk_register_mux_table(dev, name, parent_names, num_parents,
+				      flags, reg, shift, mask, clk_mux_flags,
+				      NULL, lock);
+}
diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
index 0744731..a09d7dc 100644
--- a/drivers/clk/tegra/clk.h
+++ b/drivers/clk/tegra/clk.h
@@ -355,15 +355,16 @@ struct clk *tegra_clk_register_periph_nodiv(const char *name,
 		struct tegra_clk_periph *periph, void __iomem *clk_base,
 		u32 offset);
 
-#define TEGRA_CLK_PERIPH(_mux_shift, _mux_width, _mux_flags,		\
+#define TEGRA_CLK_PERIPH(_mux_shift, _mux_mask, _mux_flags,		\
 			 _div_shift, _div_width, _div_frac_width,	\
 			 _div_flags, _clk_num, _enb_refcnt, _regs,	\
-			 _gate_flags)					\
+			 _gate_flags, _table)				\
 	{								\
 		.mux = {						\
 			.flags = _mux_flags,				\
 			.shift = _mux_shift,				\
-			.width = _mux_width,				\
+			.mask = _mux_mask,				\
+			.table = _table,				\
 		},							\
 		.divider = {						\
 			.flags = _div_flags,				\
@@ -393,26 +394,36 @@ struct tegra_periph_init_data {
 	const char *dev_id;
 };
 
-#define TEGRA_INIT_DATA(_name, _con_id, _dev_id, _parent_names, _offset, \
-			_mux_shift, _mux_width, _mux_flags, _div_shift,	\
+#define TEGRA_INIT_DATA_TABLE(_name, _con_id, _dev_id, _parent_names, _offset,\
+			_mux_shift, _mux_mask, _mux_flags, _div_shift,	\
 			_div_width, _div_frac_width, _div_flags, _regs,	\
-			_clk_num, _enb_refcnt, _gate_flags, _clk_id)	\
+			_clk_num, _enb_refcnt, _gate_flags, _clk_id, _table) \
 	{								\
 		.name = _name,						\
 		.clk_id = _clk_id,					\
 		.parent_names = _parent_names,				\
 		.num_parents = ARRAY_SIZE(_parent_names),		\
-		.periph = TEGRA_CLK_PERIPH(_mux_shift, _mux_width,	\
+		.periph = TEGRA_CLK_PERIPH(_mux_shift, _mux_mask,	\
 					   _mux_flags, _div_shift,	\
 					   _div_width, _div_frac_width,	\
 					   _div_flags, _clk_num,	\
 					   _enb_refcnt, _regs,		\
-					   _gate_flags),		\
+					   _gate_flags, _table),	\
 		.offset = _offset,					\
 		.con_id = _con_id,					\
 		.dev_id = _dev_id,					\
 	}
 
+#define TEGRA_INIT_DATA(_name, _con_id, _dev_id, _parent_names, _offset,\
+			_mux_shift, _mux_width, _mux_flags, _div_shift,	\
+			_div_width, _div_frac_width, _div_flags, _regs,	\
+			_clk_num, _enb_refcnt, _gate_flags, _clk_id)	\
+	TEGRA_INIT_DATA_TABLE(_name, _con_id, _dev_id, _parent_names, _offset,\
+			_mux_shift, BIT(_mux_width) - 1, _mux_flags,	\
+			_div_shift, _div_width, _div_frac_width, _div_flags, \
+			_regs, _clk_num, _enb_refcnt, _gate_flags, _clk_id,\
+			NULL)
+
 /**
  * struct clk_super_mux - super clock
  *
diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h
index 9c7f580..53d39c2 100644
--- a/include/linux/clk-private.h
+++ b/include/linux/clk-private.h
@@ -144,12 +144,13 @@ struct clk {
 
 #define DEFINE_CLK_MUX(_name, _parent_names, _parents, _flags,	\
 				_reg, _shift, _width,		\
-				_mux_flags, _lock)		\
+				_mux_flags, _table, _lock)	\
 	static struct clk _name;				\
 	static struct clk_mux _name##_hw = {			\
 		.hw = {						\
 			.clk = &_name,				\
 		},						\
+		.table = _table,				\
 		.reg = _reg,					\
 		.shift = _shift,				\
 		.width = _width,				\
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 7f197d7..fc435bb 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -287,8 +287,9 @@ struct clk *clk_register_divider_table(struct device *dev, const char *name,
 struct clk_mux {
 	struct clk_hw	hw;
 	void __iomem	*reg;
+	u32		*table;
+	u32		mask;
 	u8		shift;
-	u8		width;
 	u8		flags;
 	spinlock_t	*lock;
 };
@@ -297,11 +298,17 @@ struct clk_mux {
 #define CLK_MUX_INDEX_BIT		BIT(1)
 
 extern const struct clk_ops clk_mux_ops;
+
 struct clk *clk_register_mux(struct device *dev, const char *name,
 		const char **parent_names, u8 num_parents, unsigned long flags,
 		void __iomem *reg, u8 shift, u8 width,
 		u8 clk_mux_flags, spinlock_t *lock);
 
+struct clk *clk_register_mux_table(struct device *dev, const char *name,
+		const char **parent_names, u8 num_parents, unsigned long flags,
+		void __iomem *reg, u8 shift, u32 mask,
+		u8 clk_mux_flags, u32 *table, spinlock_t *lock);
+
 /**
  * struct clk_fixed_factor - fixed multiplier and divider clock
  *
-- 
1.7.10.4




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