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Message-Id: <20221231173055.42384-1-samuel@sholland.org>
Date:   Sat, 31 Dec 2022 11:30:55 -0600
From:   Samuel Holland <samuel@...lland.org>
To:     Chen-Yu Tsai <wens@...e.org>,
        Jernej Skrabec <jernej.skrabec@...il.com>
Cc:     Samuel Holland <samuel@...lland.org>,
        Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>,
        linux-arm-kernel@...ts.infradead.org, linux-clk@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-sunxi@...ts.linux.dev
Subject: [PATCH v2] clk: sunxi-ng: Avoid computing the rate twice

The ccu_*_find_best() functions already compute a best_rate at the same
time as the other factors. Return this value so the caller does not need
to duplicate the computation.

Signed-off-by: Samuel Holland <samuel@...lland.org>
---

Changes in v2:
 - Apply the same change also to nk, nkm, nkmp, and nm
 - Update the commit message

 drivers/clk/sunxi-ng/ccu_mp.c   | 11 ++++++-----
 drivers/clk/sunxi-ng/ccu_nk.c   |  9 +++++----
 drivers/clk/sunxi-ng/ccu_nkm.c  | 10 +++++-----
 drivers/clk/sunxi-ng/ccu_nkmp.c | 10 +++++-----
 drivers/clk/sunxi-ng/ccu_nm.c   |  9 +++++----
 5 files changed, 26 insertions(+), 23 deletions(-)

diff --git a/drivers/clk/sunxi-ng/ccu_mp.c b/drivers/clk/sunxi-ng/ccu_mp.c
index 57cf2d615148..cc94a694cb67 100644
--- a/drivers/clk/sunxi-ng/ccu_mp.c
+++ b/drivers/clk/sunxi-ng/ccu_mp.c
@@ -10,9 +10,9 @@
 #include "ccu_gate.h"
 #include "ccu_mp.h"
 
-static void ccu_mp_find_best(unsigned long parent, unsigned long rate,
-			     unsigned int max_m, unsigned int max_p,
-			     unsigned int *m, unsigned int *p)
+static unsigned long ccu_mp_find_best(unsigned long parent, unsigned long rate,
+				      unsigned int max_m, unsigned int max_p,
+				      unsigned int *m, unsigned int *p)
 {
 	unsigned long best_rate = 0;
 	unsigned int best_m = 0, best_p = 0;
@@ -35,6 +35,8 @@ static void ccu_mp_find_best(unsigned long parent, unsigned long rate,
 
 	*m = best_m;
 	*p = best_p;
+
+	return best_rate;
 }
 
 static unsigned long ccu_mp_find_best_with_parent_adj(struct clk_hw *hw,
@@ -109,8 +111,7 @@ static unsigned long ccu_mp_round_rate(struct ccu_mux_internal *mux,
 	max_p = cmp->p.max ?: 1 << ((1 << cmp->p.width) - 1);
 
 	if (!clk_hw_can_set_rate_parent(&cmp->common.hw)) {
-		ccu_mp_find_best(*parent_rate, rate, max_m, max_p, &m, &p);
-		rate = *parent_rate / p / m;
+		rate = ccu_mp_find_best(*parent_rate, rate, max_m, max_p, &m, &p);
 	} else {
 		rate = ccu_mp_find_best_with_parent_adj(hw, parent_rate, rate,
 							max_m, max_p);
diff --git a/drivers/clk/sunxi-ng/ccu_nk.c b/drivers/clk/sunxi-ng/ccu_nk.c
index c4fb82af97e8..8aa35d5804f3 100644
--- a/drivers/clk/sunxi-ng/ccu_nk.c
+++ b/drivers/clk/sunxi-ng/ccu_nk.c
@@ -15,8 +15,8 @@ struct _ccu_nk {
 	unsigned long	k, min_k, max_k;
 };
 
-static void ccu_nk_find_best(unsigned long parent, unsigned long rate,
-			     struct _ccu_nk *nk)
+static unsigned long ccu_nk_find_best(unsigned long parent, unsigned long rate,
+				      struct _ccu_nk *nk)
 {
 	unsigned long best_rate = 0;
 	unsigned int best_k = 0, best_n = 0;
@@ -39,6 +39,8 @@ static void ccu_nk_find_best(unsigned long parent, unsigned long rate,
 
 	nk->k = best_k;
 	nk->n = best_n;
+
+	return best_rate;
 }
 
 static void ccu_nk_disable(struct clk_hw *hw)
@@ -104,8 +106,7 @@ static long ccu_nk_round_rate(struct clk_hw *hw, unsigned long rate,
 	_nk.min_k = nk->k.min ?: 1;
 	_nk.max_k = nk->k.max ?: 1 << nk->k.width;
 
-	ccu_nk_find_best(*parent_rate, rate, &_nk);
-	rate = *parent_rate * _nk.n * _nk.k;
+	rate = ccu_nk_find_best(*parent_rate, rate, &_nk);
 
 	if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV)
 		rate = rate / nk->fixed_post_div;
diff --git a/drivers/clk/sunxi-ng/ccu_nkm.c b/drivers/clk/sunxi-ng/ccu_nkm.c
index 67da2c189b53..a0978a50edae 100644
--- a/drivers/clk/sunxi-ng/ccu_nkm.c
+++ b/drivers/clk/sunxi-ng/ccu_nkm.c
@@ -16,8 +16,8 @@ struct _ccu_nkm {
 	unsigned long	m, min_m, max_m;
 };
 
-static void ccu_nkm_find_best(unsigned long parent, unsigned long rate,
-			      struct _ccu_nkm *nkm)
+static unsigned long ccu_nkm_find_best(unsigned long parent, unsigned long rate,
+				       struct _ccu_nkm *nkm)
 {
 	unsigned long best_rate = 0;
 	unsigned long best_n = 0, best_k = 0, best_m = 0;
@@ -45,6 +45,8 @@ static void ccu_nkm_find_best(unsigned long parent, unsigned long rate,
 	nkm->n = best_n;
 	nkm->k = best_k;
 	nkm->m = best_m;
+
+	return best_rate;
 }
 
 static void ccu_nkm_disable(struct clk_hw *hw)
@@ -122,9 +124,7 @@ 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;
 
-	ccu_nkm_find_best(*parent_rate, rate, &_nkm);
-
-	rate = *parent_rate * _nkm.n * _nkm.k / _nkm.m;
+	rate = ccu_nkm_find_best(*parent_rate, rate, &_nkm);
 
 	if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
 		rate /= nkm->fixed_post_div;
diff --git a/drivers/clk/sunxi-ng/ccu_nkmp.c b/drivers/clk/sunxi-ng/ccu_nkmp.c
index 39413cb0985c..99359a06892d 100644
--- a/drivers/clk/sunxi-ng/ccu_nkmp.c
+++ b/drivers/clk/sunxi-ng/ccu_nkmp.c
@@ -29,8 +29,8 @@ static unsigned long ccu_nkmp_calc_rate(unsigned long parent,
 	return rate;
 }
 
-static void ccu_nkmp_find_best(unsigned long parent, unsigned long rate,
-			       struct _ccu_nkmp *nkmp)
+static unsigned long ccu_nkmp_find_best(unsigned long parent, unsigned long rate,
+					struct _ccu_nkmp *nkmp)
 {
 	unsigned long best_rate = 0;
 	unsigned long best_n = 0, best_k = 0, best_m = 0, best_p = 0;
@@ -65,6 +65,8 @@ static void ccu_nkmp_find_best(unsigned long parent, unsigned long rate,
 	nkmp->k = best_k;
 	nkmp->m = best_m;
 	nkmp->p = best_p;
+
+	return best_rate;
 }
 
 static void ccu_nkmp_disable(struct clk_hw *hw)
@@ -150,10 +152,8 @@ static long ccu_nkmp_round_rate(struct clk_hw *hw, unsigned long rate,
 	_nkmp.min_p = 1;
 	_nkmp.max_p = nkmp->p.max ?: 1 << ((1 << nkmp->p.width) - 1);
 
-	ccu_nkmp_find_best(*parent_rate, rate, &_nkmp);
+	rate = ccu_nkmp_find_best(*parent_rate, rate, &_nkmp);
 
-	rate = ccu_nkmp_calc_rate(*parent_rate, _nkmp.n, _nkmp.k,
-				  _nkmp.m, _nkmp.p);
 	if (nkmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
 		rate = rate / nkmp->fixed_post_div;
 
diff --git a/drivers/clk/sunxi-ng/ccu_nm.c b/drivers/clk/sunxi-ng/ccu_nm.c
index 9ca9257f4426..c1fd11542c45 100644
--- a/drivers/clk/sunxi-ng/ccu_nm.c
+++ b/drivers/clk/sunxi-ng/ccu_nm.c
@@ -27,8 +27,8 @@ static unsigned long ccu_nm_calc_rate(unsigned long parent,
 	return rate;
 }
 
-static void ccu_nm_find_best(unsigned long parent, unsigned long rate,
-			     struct _ccu_nm *nm)
+static unsigned long ccu_nm_find_best(unsigned long parent, unsigned long rate,
+				      struct _ccu_nm *nm)
 {
 	unsigned long best_rate = 0;
 	unsigned long best_n = 0, best_m = 0;
@@ -52,6 +52,8 @@ static void ccu_nm_find_best(unsigned long parent, unsigned long rate,
 
 	nm->n = best_n;
 	nm->m = best_m;
+
+	return best_rate;
 }
 
 static void ccu_nm_disable(struct clk_hw *hw)
@@ -157,8 +159,7 @@ 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;
 
-	ccu_nm_find_best(*parent_rate, rate, &_nm);
-	rate = ccu_nm_calc_rate(*parent_rate, _nm.n, _nm.m);
+	rate = ccu_nm_find_best(*parent_rate, rate, &_nm);
 
 	if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV)
 		rate /= nm->fixed_post_div;
-- 
2.37.4

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