On Wed, Nov 9, 2016 at 1:23 AM, Maxime Ripard
<maxime.rip...@free-electrons.com> wrote:
It'd be better if you mentioned what clock needs this.
> Signed-off-by: Maxime Ripard <maxime.rip...@free-electrons.com>
> ---
> drivers/clk/sunxi-ng/ccu_nkm.c | 17 ++++++++++++++---
> drivers/clk/sunxi-ng/ccu_nkm.h | 2 ++
> 2 files changed, 16 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/clk/sunxi-ng/ccu_nkm.c b/drivers/clk/sunxi-ng/ccu_nkm.c
> index 9b840a47a94d..fd3c6a9d987c 100644
> --- a/drivers/clk/sunxi-ng/ccu_nkm.c
> +++ b/drivers/clk/sunxi-ng/ccu_nkm.c
> @@ -75,7 +75,7 @@ static unsigned long ccu_nkm_recalc_rate(struct clk_hw *hw,
> unsigned long parent_rate)
> {
> struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
> - unsigned long n, m, k;
> + unsigned long rate, n, m, k;
> u32 reg;
>
> reg = readl(nkm->common.base + nkm->common.reg);
> @@ -89,7 +89,11 @@ static unsigned long ccu_nkm_recalc_rate(struct clk_hw *hw,
> m = reg >> nkm->m.shift;
> m &= (1 << nkm->m.width) - 1;
>
> - return parent_rate * (n + 1) * (k + 1) / (m + 1);
> + rate = parent_rate * (n + 1) * (k + 1) / (m + 1);
> + if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
> + rate /= nkm->fixed_post_div;
> +
> + return rate;
> }
>
> static unsigned long ccu_nkm_round_rate(struct ccu_mux_internal *mux,
> @@ -100,6 +104,9 @@ static unsigned long ccu_nkm_round_rate(struct
> ccu_mux_internal *mux,
> struct ccu_nkm *nkm = data;
> struct _ccu_nkm _nkm;
>
> + if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
> + rate *= nkm->fixed_post_div;
> +
> _nkm.min_n = nkm->n.min;
> _nkm.max_n = 1 << nkm->n.width;
> _nkm.min_k = nkm->k.min;
> @@ -109,7 +116,11 @@ static unsigned long ccu_nkm_round_rate(struct
> ccu_mux_internal *mux,
>
> ccu_nkm_find_best(parent_rate, rate, &_nkm);
>
> - return parent_rate * _nkm.n * _nkm.k / _nkm.m;
> + rate = parent_rate * _nkm.n * _nkm.k / _nkm.m;
> + if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
> + rate = rate / nkm->fixed_post_div;
> +
> + return rate;
> }
>
You also need to handle this in the set_rate callback. You might need
to read back
the parent index value to determine if the post divider applies, as
this clock supports
a mux. Or don't support mux + post-div, and leave a TODO note.
ChenYu
> static int ccu_nkm_determine_rate(struct clk_hw *hw,
> diff --git a/drivers/clk/sunxi-ng/ccu_nkm.h b/drivers/clk/sunxi-ng/ccu_nkm.h
> index 34580894f4d1..0f1dbca25719 100644
> --- a/drivers/clk/sunxi-ng/ccu_nkm.h
> +++ b/drivers/clk/sunxi-ng/ccu_nkm.h
> @@ -32,6 +32,8 @@ struct ccu_nkm {
> struct ccu_mult_internal n;
> struct ccu_mult_internal k;
> struct ccu_div_internal m;
> +
> + unsigned int fixed_post_div;
> struct ccu_mux_internal mux;
>
> struct ccu_common common;
> --
> git-series 0.8.11
