linux-kernel - [PATCH v2 1/4] clk: Compute masks for fractional

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Date:   Sun,  2 Apr 2023 11:42:04 +0200
From:   Christophe JAILLET <christophe.jaillet@...adoo.fr>
To:     mturquette@...libre.com, sboyd@...nel.org, abelvesa@...nel.org,
        peng.fan@....com, shawnguo@...nel.org, s.hauer@...gutronix.de,
        kernel@...gutronix.de, festevam@...il.com, linux-imx@....com,
        heiko@...ech.de
Cc:     linux-clk@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-rockchip@...ts.infradead.org, linux-kernel@...r.kernel.org,
        kernel-janitors@...r.kernel.org,
        Christophe JAILLET <christophe.jaillet@...adoo.fr>
Subject: [PATCH v2 1/4] clk: Compute masks for fractional_divider clk when needed.

There is no real need to pre-compute mmask and nmask when handling
fractional_divider clk.

They can be computed when needed.

Signed-off-by: Christophe JAILLET <christophe.jaillet@...adoo.fr>
---
 drivers/clk/clk-fractional-divider.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/clk-fractional-divider.c b/drivers/clk/clk-fractional-divider.c
index 6affe3565025..479297763e70 100644
--- a/drivers/clk/clk-fractional-divider.c
+++ b/drivers/clk/clk-fractional-divider.c
@@ -71,6 +71,7 @@ static void clk_fd_get_div(struct clk_hw *hw, struct u32_fract *fract)
 	struct clk_fractional_divider *fd = to_clk_fd(hw);
 	unsigned long flags = 0;
 	unsigned long m, n;
+	u32 mmask, nmask;
 	u32 val;
 
 	if (fd->lock)
@@ -85,8 +86,11 @@ static void clk_fd_get_div(struct clk_hw *hw, struct u32_fract *fract)
 	else
 		__release(fd->lock);
 
-	m = (val & fd->mmask) >> fd->mshift;
-	n = (val & fd->nmask) >> fd->nshift;
+	mmask = GENMASK(fd->mwidth - 1, 0) << fd->mshift;
+	nmask = GENMASK(fd->nwidth - 1, 0) << fd->nshift;
+
+	m = (val & mmask) >> fd->mshift;
+	n = (val & nmask) >> fd->nshift;
 
 	if (fd->flags & CLK_FRAC_DIVIDER_ZERO_BASED) {
 		m++;
@@ -166,6 +170,7 @@ static int clk_fd_set_rate(struct clk_hw *hw, unsigned long rate,
 	struct clk_fractional_divider *fd = to_clk_fd(hw);
 	unsigned long flags = 0;
 	unsigned long m, n;
+	u32 mmask, nmask;
 	u32 val;
 
 	rational_best_approximation(rate, parent_rate,
@@ -182,8 +187,11 @@ static int clk_fd_set_rate(struct clk_hw *hw, unsigned long rate,
 	else
 		__acquire(fd->lock);
 
+	mmask = GENMASK(fd->mwidth - 1, 0) << fd->mshift;
+	nmask = GENMASK(fd->nwidth - 1, 0) << fd->nshift;
+
 	val = clk_fd_readl(fd);
-	val &= ~(fd->mmask | fd->nmask);
+	val &= ~(mmask | nmask);
 	val |= (m << fd->mshift) | (n << fd->nshift);
 	clk_fd_writel(fd, val);
 
@@ -260,10 +268,8 @@ struct clk_hw *clk_hw_register_fractional_divider(struct device *dev,
 	fd->reg = reg;
 	fd->mshift = mshift;
 	fd->mwidth = mwidth;
-	fd->mmask = GENMASK(mwidth - 1, 0) << mshift;
 	fd->nshift = nshift;
 	fd->nwidth = nwidth;
-	fd->nmask = GENMASK(nwidth - 1, 0) << nshift;
 	fd->flags = clk_divider_flags;
 	fd->lock = lock;
 	fd->hw.init = &init;
-- 
2.34.1