diff mbox series

[v2,06/28] clk: renesas: rzg2l: remove critical area

Message ID 20230929053915.1530607-7-claudiu.beznea@bp.renesas.com
State New
Headers show
Series Add new Renesas RZ/G3S SoC and RZ/G3S SMARC EVK | expand

Commit Message

Claudiu Sept. 29, 2023, 5:38 a.m. UTC 
From: Claudiu Beznea <claudiu.beznea.uj@bp.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. With this only
one write to one clock register is executed thus locking/unlocking rmw_lock
is removed.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
---

Changes in v2:
- removed also the spinlock
- s/reduce/remove in patch title

 drivers/clk/renesas/rzg2l-cpg.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

Comments

Geert Uytterhoeven Oct. 4, 2023, 8:11 a.m. UTC | #1 
On Fri, Sep 29, 2023 at 7:39 AM Claudiu <claudiu.beznea@tuxon.dev> wrote:
> From: Claudiu Beznea <claudiu.beznea.uj@bp.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. With this only
> one write to one clock register is executed thus locking/unlocking rmw_lock
> is removed.
>
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
> ---
>
> Changes in v2:
> - removed also the spinlock
> - s/reduce/remove in patch title

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
i.e. will queue in renesas-clk-for-v6.7.

Gr{oetje,eeting}s,

                        Geert
diff mbox series

Patch

diff --git a/drivers/clk/renesas/rzg2l-cpg.c b/drivers/clk/renesas/rzg2l-cpg.c
index f411e428196c..d936832e098f 100644
--- a/drivers/clk/renesas/rzg2l-cpg.c
+++ b/drivers/clk/renesas/rzg2l-cpg.c
@@ -895,7 +895,6 @@  static int rzg2l_mod_clock_endisable(struct clk_hw *hw, bool enable)
 	struct rzg2l_cpg_priv *priv = clock->priv;
 	unsigned int reg = clock->off;
 	struct device *dev = priv->dev;
-	unsigned long flags;
 	u32 bitmask = BIT(clock->bit);
 	u32 value;
 	int error;
@@ -907,14 +906,12 @@  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_unlock_irqrestore(&priv->rmw_lock, flags);
+	writel(value, priv->base + CLK_ON_R(reg));
 
 	if (!enable)
 		return 0;