Unverified Commit a5ebc336 authored by Jernej Skrabec's avatar Jernej Skrabec Committed by Maxime Ripard
Browse files

clk: sunxi-ng: Use u64 for calculation of nkmp rate 



When parent rate is 24MHz and multiplier N >= 180, intermediate clock
rate doesn't fit in 32 bit variable anymore.

Because of that, introduce function for calculating clock rate which
uses 64 bit variable for intermediate result.

Acked-by: default avatarMaxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: default avatarJernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: default avatarMaxime Ripard <maxime.ripard@bootlin.com>
parent d897ef56

drivers/clk/sunxi-ng/ccu_nkmp.c

+18 −3
Original line number Diff line number Diff line
@@ -20,6 +20,18 @@ struct _ccu_nkmp { 
	unsigned long	p, min_p, max_p;

};



static unsigned long ccu_nkmp_calc_rate(unsigned long parent,

					unsigned long n, unsigned long k,

					unsigned long m, unsigned long p)

{

	u64 rate = parent;



	rate *= n * k;

	do_div(rate, m * p);



	return rate;

}



static void ccu_nkmp_find_best(unsigned long parent, unsigned long rate,

			       struct _ccu_nkmp *nkmp)

{
@@ -33,7 +45,9 @@ static void ccu_nkmp_find_best(unsigned long parent, unsigned long rate, 
				for (_p = nkmp->min_p; _p <= nkmp->max_p; _p <<= 1) {

					unsigned long tmp_rate;



					tmp_rate = parent * _n * _k / (_m * _p);

					tmp_rate = ccu_nkmp_calc_rate(parent,

								      _n, _k,

								      _m, _p);



					if (tmp_rate > rate)

						continue;
@@ -107,7 +121,7 @@ static unsigned long ccu_nkmp_recalc_rate(struct clk_hw *hw, 
	p = reg >> nkmp->p.shift;

	p &= (1 << nkmp->p.width) - 1;



	return (parent_rate * n * k >> p) / m;

	return ccu_nkmp_calc_rate(parent_rate, n, k, m, 1 << p);

}



static long ccu_nkmp_round_rate(struct clk_hw *hw, unsigned long rate,
@@ -127,7 +141,8 @@ static long ccu_nkmp_round_rate(struct clk_hw *hw, unsigned long rate, 


	ccu_nkmp_find_best(*parent_rate, rate, &_nkmp);



	return *parent_rate * _nkmp.n * _nkmp.k / (_nkmp.m * _nkmp.p);

	return ccu_nkmp_calc_rate(*parent_rate, _nkmp.n, _nkmp.k,

				  _nkmp.m, _nkmp.p);

}



static int ccu_nkmp_set_rate(struct clk_hw *hw, unsigned long rate,

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