linux-kernel - [PATCH 12/37] clk: renesas: rzg2l: reduce the critical area

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Message-Id: <20230912045157.177966-13-claudiu.beznea.uj@bp.renesas.com>
Date:   Tue, 12 Sep 2023 07:51:32 +0300
From:   Claudiu <claudiu.beznea@...on.dev>
To:     geert+renesas@...der.be, mturquette@...libre.com, sboyd@...nel.org,
        robh+dt@...nel.org, krzysztof.kozlowski+dt@...aro.org,
        conor+dt@...nel.org, ulf.hansson@...aro.org,
        linus.walleij@...aro.org, gregkh@...uxfoundation.org,
        jirislaby@...nel.org, magnus.damm@...il.com,
        catalin.marinas@....com, will@...nel.org,
        prabhakar.mahadev-lad.rj@...renesas.com,
        biju.das.jz@...renesas.com, quic_bjorande@...cinc.com,
        arnd@...db.de, konrad.dybcio@...aro.org, neil.armstrong@...aro.org,
        nfraprado@...labora.com, rafal@...ecki.pl,
        wsa+renesas@...g-engineering.com
Cc:     linux-renesas-soc@...r.kernel.org, linux-clk@...r.kernel.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-mmc@...r.kernel.org, linux-gpio@...r.kernel.org,
        linux-serial@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        Claudiu Beznea <claudiu.beznea.uj@...renesas.com>
Subject: [PATCH 12/37] clk: renesas: rzg2l: reduce the critical area

From: Claudiu Beznea <claudiu.beznea.uj@...renesas.com>

spinlock in rzg2l_mod_clock_endisable() is intended to protect the accesses
to hardware register. There is no need to protect the instructions that set
temporary variable which will be then written to register. Thus limit the
spinlock only to the hardware register access.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@...renesas.com>
---
 drivers/clk/renesas/rzg2l-cpg.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/renesas/rzg2l-cpg.c b/drivers/clk/renesas/rzg2l-cpg.c
index 6c289223a4e2..d8801f88df8e 100644
--- a/drivers/clk/renesas/rzg2l-cpg.c
+++ b/drivers/clk/renesas/rzg2l-cpg.c
@@ -912,13 +912,13 @@ static int rzg2l_mod_clock_endisable(struct clk_hw *hw, bool enable)
 
 	dev_dbg(dev, "CLK_ON %u/%pC %s\n", CLK_ON_R(reg), hw->clk,
 		enable ? "ON" : "OFF");
-	spin_lock_irqsave(&priv->rmw_lock, flags);
 
 	value = bitmask << 16;
 	if (enable)
 		value |= bitmask;
-	writel(value, priv->base + CLK_ON_R(reg));
 
+	spin_lock_irqsave(&priv->rmw_lock, flags);
+	writel(value, priv->base + CLK_ON_R(reg));
 	spin_unlock_irqrestore(&priv->rmw_lock, flags);
 
 	if (!enable)
-- 
2.39.2