[PATCH] clk: add table lookup to mux
Mike Turquette
mturquette at linaro.org
Tue Mar 19 17:33:09 EDT 2013
Quoting Peter De Schrijver (2013-03-12 11:42:23)
> 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>
Do you actually need arbitrary masks instead of a continuous bitfield?
Or does this change just make it easier for you to convert existing
data?
Thanks,
Mike
>
> --
> 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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