Commit 088cefca authored by Frank Oltmanns's avatar Frank Oltmanns Committed by Chen-Yu Tsai
Browse files

clk: sunxi-ng: nkm: Support finding closest rate 



When finding the best rate for a NKM clock, consider rates that are
higher than the requested rate, if the CCU_FEATURE_CLOSEST_RATE flag is
set by using the helper function ccu_is_better_rate().

Accommodate ccu_mux_helper_determine_rate to this change.

Acked-by: default avatarMaxime Ripard <mripard@kernel.org>
Reviewed-by: default avatarJernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: default avatarFrank Oltmanns <frank@oltmanns.dev>
Link: https://lore.kernel.org/r/20230807-pll-mipi_set_rate_parent-v6-7-f173239a4b59@oltmanns.dev


Signed-off-by: default avatarChen-Yu Tsai <wens@csie.org>
parent c0380d14

drivers/clk/sunxi-ng/ccu_mux.c

+1 −1
Original line number Diff line number Diff line
@@ -139,7 +139,7 @@ int ccu_mux_helper_determine_rate(struct ccu_common *common, 
			goto out;

		}



		if ((req->rate - tmp_rate) < (req->rate - best_rate)) {

		if (ccu_is_better_rate(common, req->rate, tmp_rate, best_rate)) {

			best_rate = tmp_rate;

			best_parent_rate = parent_rate;

			best_parent = parent;

drivers/clk/sunxi-ng/ccu_nkm.c

+9 −11
Original line number Diff line number Diff line
@@ -16,7 +16,8 @@ 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,

static unsigned long ccu_nkm_find_best_with_parent_adj(struct ccu_common *common,

						       struct clk_hw *parent_hw,

						       unsigned long *parent, unsigned long rate,

						       struct _ccu_nkm *nkm)

{
@@ -32,10 +33,8 @@ static unsigned long ccu_nkm_find_best_with_parent_adj(struct clk_hw *parent_hw, 
				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)) {

				if (ccu_is_better_rate(common, rate, tmp_rate, best_rate)) {

					best_rate = tmp_rate;

					best_parent_rate = tmp_parent;

					best_n = _n;
@@ -56,7 +55,7 @@ static unsigned long ccu_nkm_find_best_with_parent_adj(struct clk_hw *parent_hw, 
}



static unsigned long ccu_nkm_find_best(unsigned long parent, unsigned long rate,

				       struct _ccu_nkm *nkm)

				       struct _ccu_nkm *nkm, struct ccu_common *common)

{

	unsigned long best_rate = 0;

	unsigned long best_n = 0, best_k = 0, best_m = 0;
@@ -69,9 +68,7 @@ static unsigned long ccu_nkm_find_best(unsigned long parent, unsigned long rate, 


				tmp_rate = parent * _n * _k / _m;



				if (tmp_rate > rate)

					continue;

				if ((rate - tmp_rate) < (rate - best_rate)) {

				if (ccu_is_better_rate(common, rate, tmp_rate, best_rate)) {

					best_rate = tmp_rate;

					best_n = _n;

					best_k = _k;
@@ -164,9 +161,10 @@ static unsigned long ccu_nkm_round_rate(struct ccu_mux_internal *mux, 
		rate *= nkm->fixed_post_div;



	if (!clk_hw_can_set_rate_parent(&nkm->common.hw))

		rate = ccu_nkm_find_best(*parent_rate, rate, &_nkm);

		rate = ccu_nkm_find_best(*parent_rate, rate, &_nkm, &nkm->common);

	else

		rate = ccu_nkm_find_best_with_parent_adj(parent_hw, parent_rate, rate, &_nkm);

		rate = ccu_nkm_find_best_with_parent_adj(&nkm->common, parent_hw, parent_rate, rate,

							 &_nkm);



	if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)

		rate /= nkm->fixed_post_div;
@@ -201,7 +199,7 @@ static int ccu_nkm_set_rate(struct clk_hw *hw, unsigned long rate, 
	_nkm.min_m = 1;

	_nkm.max_m = nkm->m.max ?: 1 << nkm->m.width;



	ccu_nkm_find_best(parent_rate, rate, &_nkm);

	ccu_nkm_find_best(parent_rate, rate, &_nkm, &nkm->common);



	spin_lock_irqsave(nkm->common.lock, flags);