diff options
Diffstat (limited to 'drivers/clk/sunxi-ng/ccu_nkm.c')
-rw-r--r-- | drivers/clk/sunxi-ng/ccu_nkm.c | 44 |
1 files changed, 43 insertions, 1 deletions
diff --git a/drivers/clk/sunxi-ng/ccu_nkm.c b/drivers/clk/sunxi-ng/ccu_nkm.c index f267142e58b3..2f60f3c33e30 100644 --- a/drivers/clk/sunxi-ng/ccu_nkm.c +++ b/drivers/clk/sunxi-ng/ccu_nkm.c @@ -16,6 +16,45 @@ struct _ccu_nkm { unsigned long m, min_m, max_m; }; +static unsigned long ccu_nkm_find_best_with_parent_adj(struct clk_hw *parent_hw, + unsigned long *parent, unsigned long rate, + struct _ccu_nkm *nkm) +{ + unsigned long best_rate = 0, best_parent_rate = *parent, tmp_parent = *parent; + unsigned long best_n = 0, best_k = 0, best_m = 0; + unsigned long _n, _k, _m; + + for (_k = nkm->min_k; _k <= nkm->max_k; _k++) { + for (_n = nkm->min_n; _n <= nkm->max_n; _n++) { + for (_m = nkm->min_m; _m <= nkm->max_m; _m++) { + unsigned long tmp_rate; + + tmp_parent = clk_hw_round_rate(parent_hw, rate * _m / (_n * _k)); + + tmp_rate = tmp_parent * _n * _k / _m; + if (tmp_rate > rate) + continue; + + if ((rate - tmp_rate) < (rate - best_rate)) { + best_rate = tmp_rate; + best_parent_rate = tmp_parent; + best_n = _n; + best_k = _k; + best_m = _m; + } + } + } + } + + nkm->n = best_n; + nkm->k = best_k; + nkm->m = best_m; + + *parent = best_parent_rate; + + return best_rate; +} + static unsigned long ccu_nkm_find_best(unsigned long parent, unsigned long rate, struct _ccu_nkm *nkm) { @@ -124,7 +163,10 @@ static unsigned long ccu_nkm_round_rate(struct ccu_mux_internal *mux, if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV) rate *= nkm->fixed_post_div; - rate = ccu_nkm_find_best(*parent_rate, rate, &_nkm); + if (!clk_hw_can_set_rate_parent(&nkm->common.hw)) + rate = ccu_nkm_find_best(*parent_rate, rate, &_nkm); + else + rate = ccu_nkm_find_best_with_parent_adj(parent_hw, parent_rate, rate, &_nkm); if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV) rate /= nkm->fixed_post_div; |