[PATCH 0/2] Table lookup for mux clock type

[PATCH 0/2] Table lookup for mux clock type

[Peter De Schrijver]

This patchset adds a table lookup feature to the mux clock type. This will
be used by the forthcoming Tegra114 clock implementation. Also instead of
a fixed field width, a mask is used. This is because Tegra114 has some muxes
where the parent selector is spread over several bitfields. The second patch
adapts the tegra periph clock implementation which uses struct clk_mux
directly.

Peter De Schrijver (2):
  clk: add table lookup to mux
  clk: tegra: adapt tegra periph clk to mux table/mask

 drivers/clk/clk-mux.c        |   51 ++++++++++++++++++++++++++++++++---------
 drivers/clk/tegra/clk.h      |   27 +++++++++++++++------
 include/linux/clk-private.h  |    3 +-
 include/linux/clk-provider.h |    9 ++++++-
 4 files changed, 69 insertions(+), 21 deletions(-)

-- 
1.7.7.rc0.72.g4b5ea.dirty

[PATCH 1/2] clk: add table lookup to mux

[Peter De Schrijver]

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.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
---
 drivers/clk/clk-mux.c        |   51 ++++++++++++++++++++++++++++++++---------
 include/linux/clk-private.h  |    3 +-
 include/linux/clk-provider.h |    9 ++++++-
 3 files changed, 50 insertions(+), 13 deletions(-)

diff --git a/drivers/clk/clk-mux.c b/drivers/clk/clk-mux.c
index 508c032..2c98744 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 +43,17 @@ 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;
+		if (i == num_parents)
+			return -EINVAL;
+	}
 
 	if (val && (mux->flags & CLK_MUX_INDEX_BIT))
 		val = ffs(val) - 1;
@@ -50,7 +61,7 @@ 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 +73,22 @@ 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];
+
+	else {
+		if (mux->flags & CLK_MUX_INDEX_BIT)
+			index = (1 << ffs(index));
 
-	if (mux->flags & CLK_MUX_INDEX_ONE)
-		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 +104,10 @@ 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 +129,10 @@ 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 +142,15 @@ 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/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 4989b8a..87a59ff 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
  *
-- 
1.7.7.rc0.72.g4b5ea.dirty

[PATCH 2/2] clk: tegra: adapt tegra periph clk to mux table/mask

[Peter De Schrijver]

The tegra peripheral clock type uses struct clk_mux directly, so it needs to
be updated to handle the new mask and table fields. Also the macros need
to be updated

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
---
 drivers/clk/tegra/clk.h |   27 +++++++++++++++++++--------
 1 files changed, 19 insertions(+), 8 deletions(-)

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
  *
-- 
1.7.7.rc0.72.g4b5ea.dirty

Re: [PATCH 2/2] clk: tegra: adapt tegra periph clk to mux table/mask

[Stephen Warren]

On 01/28/2013 08:54 AM, Peter De Schrijver wrote:
> The tegra peripheral clock type uses struct clk_mux directly, so it needs to
> be updated to handle the new mask and table fields. Also the macros need
> to be updated

Just a quick note on patch dependencies here:

Patch 1/2 can presumably be taken through the clk tree whenever Mike is
OK with it.

Patch 2/2 depends on patches in the Tegra tree for 3.9. Since patch 2/2
is useful mostly for the Tegra114 clock driver, and I don't imagine that
will get posted/merged in time for 3.9, it's probably easiest to just
take patch 2/2 for 3.10 along with the Tegra114 clock driver. Also, I
imagine there won't be any more clk/Tegra tree dependencies in 3.10, so
patch 2/2 and the Tegra114 clk driver patches can likely go through the
clk tree itself for 3.10.

Re: [PATCH 2/2] clk: tegra: adapt tegra periph clk to mux table/mask

[Peter De Schrijver]

On Mon, Jan 28, 2013 at 05:49:53PM +0100, Stephen Warren wrote:
> On 01/28/2013 08:54 AM, Peter De Schrijver wrote:
> > The tegra peripheral clock type uses struct clk_mux directly, so it needs to
> > be updated to handle the new mask and table fields. Also the macros need
> > to be updated
> 
> Just a quick note on patch dependencies here:
> 
> Patch 1/2 can presumably be taken through the clk tree whenever Mike is
> OK with it.
> 
> Patch 2/2 depends on patches in the Tegra tree for 3.9. Since patch 2/2
> is useful mostly for the Tegra114 clock driver, and I don't imagine that
> will get posted/merged in time for 3.9, it's probably easiest to just
> take patch 2/2 for 3.10 along with the Tegra114 clock driver. Also, I
> imagine there won't be any more clk/Tegra tree dependencies in 3.10, so
> patch 2/2 and the Tegra114 clk driver patches can likely go through the
> clk tree itself for 3.10.

No. Because 1/2 changes struct clk_mux and the tegra peripheral clock type 
uses struct clk_mux directly, 2/2 needs to be applied together with 1/2, even
if the new functionality is not yet used.

Cheers,

Peter.

Re: [PATCH 2/2] clk: tegra: adapt tegra periph clk to mux table/mask

[Stephen Warren]

On 01/29/2013 02:51 AM, Peter De Schrijver wrote:
> On Mon, Jan 28, 2013 at 05:49:53PM +0100, Stephen Warren wrote:
>> On 01/28/2013 08:54 AM, Peter De Schrijver wrote:
>>> The tegra peripheral clock type uses struct clk_mux directly, so it needs to
>>> be updated to handle the new mask and table fields. Also the macros need
>>> to be updated
>>
>> Just a quick note on patch dependencies here:
>>
>> Patch 1/2 can presumably be taken through the clk tree whenever Mike is
>> OK with it.
>>
>> Patch 2/2 depends on patches in the Tegra tree for 3.9. Since patch 2/2
>> is useful mostly for the Tegra114 clock driver, and I don't imagine that
>> will get posted/merged in time for 3.9, it's probably easiest to just
>> take patch 2/2 for 3.10 along with the Tegra114 clock driver. Also, I
>> imagine there won't be any more clk/Tegra tree dependencies in 3.10, so
>> patch 2/2 and the Tegra114 clk driver patches can likely go through the
>> clk tree itself for 3.10.
> 
> No. Because 1/2 changes struct clk_mux and the tegra peripheral clock type 
> uses struct clk_mux directly, 2/2 needs to be applied together with 1/2, even
> if the new functionality is not yet used.

Oh, then they can't be two separate patches then, or "git bisect" won't
work. I guess it's best to wait for 3.10 for this:-(