Commit c0380d14 authored by Frank Oltmanns's avatar Frank Oltmanns Committed by Chen-Yu Tsai
Browse files

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



Use the helper function ccu_is_better_rate() to determine the rate that
is closest to the requested rate, thereby supporting rates that are
higher than the requested rate if the clock uses the
CCU_FEATURE_CLOSEST_RATE.

Add the macro SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK_MIN_MAX_CLOSEST which
sets CCU_FEATURE_CLOSEST_RATE.

To avoid code duplication, add the macros
SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK_MIN_MAX_FEAT that allows selecting
arbitrary features and use it in the original
SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK_MIN_MAX as well as the newly introduced
SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK_MIN_MAX_CLOSEST macros.

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-v6-6-f173239a4b59@oltmanns.dev


Signed-off-by: default avatarChen-Yu Tsai <wens@csie.org>
parent e373315d

drivers/clk/sunxi-ng/ccu_nm.c

+5 −8
Original line number Diff line number Diff line
@@ -27,8 +27,8 @@ static unsigned long ccu_nm_calc_rate(unsigned long parent, 
	return rate;

}



static unsigned long ccu_nm_find_best(unsigned long parent, unsigned long rate,

				      struct _ccu_nm *nm)

static unsigned long ccu_nm_find_best(struct ccu_common *common, unsigned long parent,

				      unsigned long rate, struct _ccu_nm *nm)

{

	unsigned long best_rate = 0;

	unsigned long best_n = 0, best_m = 0;
@@ -39,10 +39,7 @@ static unsigned long ccu_nm_find_best(unsigned long parent, unsigned long rate, 
			unsigned long tmp_rate = ccu_nm_calc_rate(parent,

								  _n, _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_m = _m;
@@ -159,7 +156,7 @@ static long ccu_nm_round_rate(struct clk_hw *hw, unsigned long rate, 
	_nm.min_m = 1;

	_nm.max_m = nm->m.max ?: 1 << nm->m.width;



	rate = ccu_nm_find_best(*parent_rate, rate, &_nm);

	rate = ccu_nm_find_best(&nm->common, *parent_rate, rate, &_nm);



	if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV)

		rate /= nm->fixed_post_div;
@@ -210,7 +207,7 @@ static int ccu_nm_set_rate(struct clk_hw *hw, unsigned long rate, 
					   &_nm.m, &_nm.n);

	} else {

		ccu_sdm_helper_disable(&nm->common, &nm->sdm);

		ccu_nm_find_best(parent_rate, rate, &_nm);

		ccu_nm_find_best(&nm->common, parent_rate, rate, &_nm);

	}



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

drivers/clk/sunxi-ng/ccu_nm.h

+45 −3
Original line number Diff line number Diff line
@@ -108,7 +108,7 @@ struct ccu_nm { 
		},							\

	}



#define SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK_MIN_MAX(_struct, _name,	\

#define SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK_MIN_MAX_FEAT(_struct, _name,	\

						 _parent, _reg,		\

						 _min_rate, _max_rate,	\

						 _nshift, _nwidth,	\
@@ -116,7 +116,8 @@ struct ccu_nm { 
						 _frac_en, _frac_sel,	\

						 _frac_rate_0,		\

						 _frac_rate_1,		\

						 _gate, _lock, _flags)	\

						 _gate, _lock, _flags,	\

						 _features)		\

	struct ccu_nm _struct = {					\

		.enable		= _gate,				\

		.lock		= _lock,				\
@@ -129,7 +130,7 @@ struct ccu_nm { 
		.max_rate	= _max_rate,				\

		.common		= {					\

			.reg		= _reg,				\

			.features	= CCU_FEATURE_FRACTIONAL,	\

			.features	= _features,			\

			.hw.init	= CLK_HW_INIT(_name,		\

						      _parent,		\

						      &ccu_nm_ops,	\
@@ -137,6 +138,47 @@ struct ccu_nm { 
		},							\

	}



#define SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK_MIN_MAX(_struct, _name,	\

						 _parent, _reg,		\

						 _min_rate, _max_rate,	\

						 _nshift, _nwidth,	\

						 _mshift, _mwidth,	\

						 _frac_en, _frac_sel,	\

						 _frac_rate_0,		\

						 _frac_rate_1,		\

						 _gate, _lock, _flags)	\

	SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK_MIN_MAX_FEAT(_struct, _name,	\

						_parent, _reg,		\

						_min_rate, _max_rate,	\

						_nshift, _nwidth,	\

						_mshift, _mwidth,	\

						_frac_en, _frac_sel,	\

						_frac_rate_0,		\

						_frac_rate_1,		\

						_gate, _lock, _flags,	\

						CCU_FEATURE_FRACTIONAL)



#define SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK_MIN_MAX_CLOSEST(_struct, _name, \

						 _parent, _reg,		\

						 _min_rate, _max_rate,	\

						 _nshift, _nwidth,	\

						 _mshift, _mwidth,	\

						 _frac_en, _frac_sel,	\

						 _frac_rate_0,		\

						 _frac_rate_1,		\

						 _gate, _lock, _flags)	\

	SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK_MIN_MAX_FEAT(_struct, _name,	\

						_parent, _reg,		\

						_min_rate, _max_rate,	\

						_nshift, _nwidth,	\

						_mshift, _mwidth,	\

						_frac_en, _frac_sel,	\

						_frac_rate_0,		\

						_frac_rate_1,		\

						_gate, _lock, _flags,	\

						CCU_FEATURE_FRACTIONAL |\

						CCU_FEATURE_CLOSEST_RATE)



#define SUNXI_CCU_NM_WITH_GATE_LOCK(_struct, _name, _parent, _reg,	\

				    _nshift, _nwidth,			\

				    _mshift, _mwidth,			\