[PATCH v3 3/7] clk: sunxi-ng: Implement multiplier maximum

Chen-Yu Tsai wens at csie.org
Fri Jan 20 17:27:42 PST 2017


On Fri, Jan 20, 2017 at 3:29 PM, Maxime Ripard
<maxime.ripard at free-electrons.com> wrote:
> Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
> ---
>  drivers/clk/sunxi-ng/ccu_mult.c | 16 +++++++++++++---
>  drivers/clk/sunxi-ng/ccu_mult.h | 10 ++++++----
>  drivers/clk/sunxi-ng/ccu_nk.c   |  8 ++++----
>  drivers/clk/sunxi-ng/ccu_nkm.c  |  8 ++++----
>  drivers/clk/sunxi-ng/ccu_nkmp.c |  8 ++++----
>  drivers/clk/sunxi-ng/ccu_nm.c   |  4 ++--
>  6 files changed, 33 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/clk/sunxi-ng/ccu_mult.c b/drivers/clk/sunxi-ng/ccu_mult.c
> index 8b7ee7baa85b..8724c01171b1 100644
> --- a/drivers/clk/sunxi-ng/ccu_mult.c
> +++ b/drivers/clk/sunxi-ng/ccu_mult.c
> @@ -40,8 +40,13 @@ static unsigned long ccu_mult_round_rate(struct ccu_mux_internal *mux,
>         struct ccu_mult *cm = data;
>         struct _ccu_mult _cm;
>
> -       _cm.min = 1;
> -       _cm.max = 1 << cm->mult.width;
> +       _cm.min = cm->mult.min;

This particular line should probably be in a separate patch fixing
commit 2beaa601c849 ("clk: sunxi-ng: Implement minimum for multipliers")?
It kind of sticks out, and doesn't match the commit message.

> +
> +       if (cm->mult.max)
> +               _cm.max = cm->mult.max;
> +       else
> +               _cm.max = (1 << cm->mult.width) + cm->mult.offset - 1;
> +
>         ccu_mult_find_best(parent_rate, rate, &_cm);
>
>         return parent_rate * _cm.mult;
> @@ -114,7 +119,12 @@ static int ccu_mult_set_rate(struct clk_hw *hw, unsigned long rate,
>                                                 &parent_rate);
>
>         _cm.min = cm->mult.min;
> -       _cm.max = 1 << cm->mult.width;
> +
> +       if (cm->mult.max)
> +               _cm.max = cm->mult.max;
> +       else
> +               _cm.max = (1 << cm->mult.width) + cm->mult.offset - 1;

The changes look good. Thinking about this more, you might need to
adjust the default minimum to account for the offset as well? At
the moment it doesn't really affect us, as the offset is either
1 or 0, which means a minimum of 1 is equally good. But leaving
a potential error in there doesn't feel right. Said change would
be against patch 2, so

Acked-by: Chen-Yu Tsai <wens at csie.org>

for this patch once the first comment is addressed.

Regards
ChenYu

> +
>         ccu_mult_find_best(parent_rate, rate, &_cm);
>
>         spin_lock_irqsave(cm->common.lock, flags);
> diff --git a/drivers/clk/sunxi-ng/ccu_mult.h b/drivers/clk/sunxi-ng/ccu_mult.h
> index 84839641dfdf..524acddfcb2e 100644
> --- a/drivers/clk/sunxi-ng/ccu_mult.h
> +++ b/drivers/clk/sunxi-ng/ccu_mult.h
> @@ -10,24 +10,26 @@ struct ccu_mult_internal {
>         u8      shift;
>         u8      width;
>         u8      min;
> +       u8      max;
>  };
>
> -#define _SUNXI_CCU_MULT_OFFSET_MIN(_shift, _width, _offset, _min)      \
> +#define _SUNXI_CCU_MULT_OFFSET_MIN_MAX(_shift, _width, _offset, _min, _max) \
>         {                                                               \
>                 .min    = _min,                                         \
> +               .max    = _max,                                         \
>                 .offset = _offset,                                      \
>                 .shift  = _shift,                                       \
>                 .width  = _width,                                       \
>         }
>
>  #define _SUNXI_CCU_MULT_MIN(_shift, _width, _min)      \
> -       _SUNXI_CCU_MULT_OFFSET_MIN(_shift, _width, 1, _min)
> +       _SUNXI_CCU_MULT_OFFSET_MIN_MAX(_shift, _width, 1, _min, 0)
>
>  #define _SUNXI_CCU_MULT_OFFSET(_shift, _width, _offset)        \
> -       _SUNXI_CCU_MULT_OFFSET_MIN(_shift, _width, _offset, 1)
> +       _SUNXI_CCU_MULT_OFFSET_MIN_MAX(_shift, _width, _offset, 1, 0)
>
>  #define _SUNXI_CCU_MULT(_shift, _width)                \
> -       _SUNXI_CCU_MULT_OFFSET_MIN(_shift, _width, 1, 1)
> +       _SUNXI_CCU_MULT_OFFSET_MIN_MAX(_shift, _width, 1, 1, 0)
>
>  struct ccu_mult {
>         u32                     enable;
> diff --git a/drivers/clk/sunxi-ng/ccu_nk.c b/drivers/clk/sunxi-ng/ccu_nk.c
> index 90117d3ead8c..b9e9b8a9d1b4 100644
> --- a/drivers/clk/sunxi-ng/ccu_nk.c
> +++ b/drivers/clk/sunxi-ng/ccu_nk.c
> @@ -103,9 +103,9 @@ static long ccu_nk_round_rate(struct clk_hw *hw, unsigned long rate,
>                 rate *= nk->fixed_post_div;
>
>         _nk.min_n = nk->n.min;
> -       _nk.max_n = 1 << nk->n.width;
> +       _nk.max_n = nk->n.max ?: 1 << nk->n.width;
>         _nk.min_k = nk->k.min;
> -       _nk.max_k = 1 << nk->k.width;
> +       _nk.max_k = nk->k.max ?: 1 << nk->k.width;
>
>         ccu_nk_find_best(*parent_rate, rate, &_nk);
>         rate = *parent_rate * _nk.n * _nk.k;
> @@ -128,9 +128,9 @@ static int ccu_nk_set_rate(struct clk_hw *hw, unsigned long rate,
>                 rate = rate * nk->fixed_post_div;
>
>         _nk.min_n = nk->n.min;
> -       _nk.max_n = 1 << nk->n.width;
> +       _nk.max_n = nk->n.max ?: 1 << nk->n.width;
>         _nk.min_k = nk->k.min;
> -       _nk.max_k = 1 << nk->k.width;
> +       _nk.max_k = nk->k.max ?: 1 << nk->k.width;
>
>         ccu_nk_find_best(parent_rate, rate, &_nk);
>
> diff --git a/drivers/clk/sunxi-ng/ccu_nkm.c b/drivers/clk/sunxi-ng/ccu_nkm.c
> index 3caaf9d603e2..71f81e95a061 100644
> --- a/drivers/clk/sunxi-ng/ccu_nkm.c
> +++ b/drivers/clk/sunxi-ng/ccu_nkm.c
> @@ -110,9 +110,9 @@ static unsigned long ccu_nkm_round_rate(struct ccu_mux_internal *mux,
>         struct _ccu_nkm _nkm;
>
>         _nkm.min_n = nkm->n.min;
> -       _nkm.max_n = 1 << nkm->n.width;
> +       _nkm.max_n = nkm->n.max ?: 1 << nkm->n.width;
>         _nkm.min_k = nkm->k.min;
> -       _nkm.max_k = 1 << nkm->k.width;
> +       _nkm.max_k = nkm->k.max ?: 1 << nkm->k.width;
>         _nkm.min_m = 1;
>         _nkm.max_m = nkm->m.max ?: 1 << nkm->m.width;
>
> @@ -139,9 +139,9 @@ static int ccu_nkm_set_rate(struct clk_hw *hw, unsigned long rate,
>         u32 reg;
>
>         _nkm.min_n = nkm->n.min;
> -       _nkm.max_n = 1 << nkm->n.width;
> +       _nkm.max_n = nkm->n.max ?: 1 << nkm->n.width;
>         _nkm.min_k = nkm->k.min;
> -       _nkm.max_k = 1 << nkm->k.width;
> +       _nkm.max_k = nkm->k.max ?: 1 << nkm->k.width;
>         _nkm.min_m = 1;
>         _nkm.max_m = nkm->m.max ?: 1 << nkm->m.width;
>
> diff --git a/drivers/clk/sunxi-ng/ccu_nkmp.c b/drivers/clk/sunxi-ng/ccu_nkmp.c
> index da2bba02b845..a2b40a000157 100644
> --- a/drivers/clk/sunxi-ng/ccu_nkmp.c
> +++ b/drivers/clk/sunxi-ng/ccu_nkmp.c
> @@ -117,9 +117,9 @@ static long ccu_nkmp_round_rate(struct clk_hw *hw, unsigned long rate,
>         struct _ccu_nkmp _nkmp;
>
>         _nkmp.min_n = nkmp->n.min;
> -       _nkmp.max_n = 1 << nkmp->n.width;
> +       _nkmp.max_n = nkmp->n.max ?: 1 << nkmp->n.width;
>         _nkmp.min_k = nkmp->k.min;
> -       _nkmp.max_k = 1 << nkmp->k.width;
> +       _nkmp.max_k = nkmp->k.max ?: 1 << nkmp->k.width;
>         _nkmp.min_m = 1;
>         _nkmp.max_m = nkmp->m.max ?: 1 << nkmp->m.width;
>         _nkmp.min_p = 1;
> @@ -139,9 +139,9 @@ static int ccu_nkmp_set_rate(struct clk_hw *hw, unsigned long rate,
>         u32 reg;
>
>         _nkmp.min_n = 1;
> -       _nkmp.max_n = 1 << nkmp->n.width;
> +       _nkmp.max_n = nkmp->n.max ?: 1 << nkmp->n.width;
>         _nkmp.min_k = 1;
> -       _nkmp.max_k = 1 << nkmp->k.width;
> +       _nkmp.max_k = nkmp->k.max ?: 1 << nkmp->k.width;
>         _nkmp.min_m = 1;
>         _nkmp.max_m = nkmp->m.max ?: 1 << nkmp->m.width;
>         _nkmp.min_p = 1;
> diff --git a/drivers/clk/sunxi-ng/ccu_nm.c b/drivers/clk/sunxi-ng/ccu_nm.c
> index 158d74e0215f..af71b1909cd9 100644
> --- a/drivers/clk/sunxi-ng/ccu_nm.c
> +++ b/drivers/clk/sunxi-ng/ccu_nm.c
> @@ -100,7 +100,7 @@ static long ccu_nm_round_rate(struct clk_hw *hw, unsigned long rate,
>         struct _ccu_nm _nm;
>
>         _nm.min_n = nm->n.min;
> -       _nm.max_n = 1 << nm->n.width;
> +       _nm.max_n = nm->n.max ?: 1 << nm->n.width;
>         _nm.min_m = 1;
>         _nm.max_m = nm->m.max ?: 1 << nm->m.width;
>
> @@ -123,7 +123,7 @@ static int ccu_nm_set_rate(struct clk_hw *hw, unsigned long rate,
>                 ccu_frac_helper_disable(&nm->common, &nm->frac);
>
>         _nm.min_n = 1;
> -       _nm.max_n = 1 << nm->n.width;
> +       _nm.max_n = nm->n.max ?: 1 << nm->n.width;
>         _nm.min_m = 1;
>         _nm.max_m = nm->m.max ?: 1 << nm->m.width;
>
> --
> git-series 0.8.11



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