[PATCH v2] clk: meson: pll: adjust timeout in meson_clk_pll_wait_lock()

From: Heiner Kallweit <hkallweit1@gmail.com>
To: Neil Armstrong <narmstrong@baylibre.com>,
	Jerome Brunet <jbrunet@baylibre.com>,
	Michael Turquette <mturquette@baylibre.com>,
	Stephen Boyd <sboyd@kernel.org>,
	Kevin Hilman <khilman@baylibre.com>,
	Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: "open list:ARM/Amlogic Meson..."
	<linux-amlogic@lists.infradead.org>,
	linux-clk@vger.kernel.org,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>
Subject: [PATCH v2] clk: meson: pll: adjust timeout in meson_clk_pll_wait_lock()
Date: Mon, 29 Aug 2022 20:52:59 +0200	[thread overview]
Message-ID: <a801afc0-a8f2-a0a4-0f2b-a7201351d563@gmail.com> (raw)

Currently we loop over meson_parm_read() up to 24mln times.
This results in a unpredictable timeout period. In my case
it's over 5s on a S905X4-based system. Make the timeout
period predictable and set it to 100ms.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v2:
- remove an unrelated change
---
 drivers/clk/meson/clk-pll.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/meson/clk-pll.c b/drivers/clk/meson/clk-pll.c
index daa025b6d..53b8e17e4 100644
--- a/drivers/clk/meson/clk-pll.c
+++ b/drivers/clk/meson/clk-pll.c
@@ -277,15 +277,15 @@ static int meson_clk_pll_wait_lock(struct clk_hw *hw)
 {
 	struct clk_regmap *clk = to_clk_regmap(hw);
 	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
-	int delay = 24000000;
+	int delay = 5000;
 
 	do {
-		/* Is the clock locked now ? */
+		/* Is the clock locked now ? Time out after 100ms. */
 		if (meson_parm_read(clk->map, &pll->l))
 			return 0;
 
-		delay--;
-	} while (delay > 0);
+		udelay(20);
+	} while (--delay);
 
 	return -ETIMEDOUT;
 }
-- 
2.37.2

