On Sun, Nov 13, 2016 at 11:48 AM, Chen-Yu Tsai <w...@csie.org> wrote:
> 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.
Was thinking pre-dividers... sorry. Please ignore the second parent
index part.
ChenYu
>
> 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
