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From: Alexandre Belloni <alexandre.belloni@free-electrons.com>
To: Nicolas Ferre <nicolas.ferre@atmel.com>,
	Boris Brezillon <boris.brezillon@free-electrons.com>,
	Stephen Boyd <sboyd@codeaurora.org>
Cc: Michael Turquette <mturquette@baylibre.com>,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org,
	Alexandre Belloni <alexandre.belloni@free-electrons.com>
Subject: [PATCH v3 3/5] clk: at91: sckc: optimize boot time
Date: Tue, 20 Sep 2016 22:58:31 +0200	[thread overview]
Message-ID: <20160920205833.19638-4-alexandre.belloni@free-electrons.com> (raw)
In-Reply-To: <20160920205833.19638-1-alexandre.belloni@free-electrons.com>

Assume that if the oscillator is enabled (OSC32EN bit is present), the
delay has already elapsed as the bootloader probably waited for the
oscillator to settle. This could waste up to 1.2s.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 drivers/clk/at91/sckc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/at91/sckc.c b/drivers/clk/at91/sckc.c
index 60d8225715a2..b1265f2cdae7 100644
--- a/drivers/clk/at91/sckc.c
+++ b/drivers/clk/at91/sckc.c
@@ -69,7 +69,7 @@ static int clk_slow_osc_prepare(struct clk_hw *hw)
 	void __iomem *sckcr = osc->sckcr;
 	u32 tmp = readl(sckcr);
 
-	if (tmp & AT91_SCKC_OSC32BYP)
+	if (tmp & (AT91_SCKC_OSC32BYP | AT91_SCKC_OSC32EN))
 		return 0;
 
 	writel(tmp | AT91_SCKC_OSC32EN, sckcr);
-- 
2.9.3

WARNING: multiple messages have this Message-ID (diff)
From: alexandre.belloni@free-electrons.com (Alexandre Belloni)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v3 3/5] clk: at91: sckc: optimize boot time
Date: Tue, 20 Sep 2016 22:58:31 +0200	[thread overview]
Message-ID: <20160920205833.19638-4-alexandre.belloni@free-electrons.com> (raw)
In-Reply-To: <20160920205833.19638-1-alexandre.belloni@free-electrons.com>

Assume that if the oscillator is enabled (OSC32EN bit is present), the
delay has already elapsed as the bootloader probably waited for the
oscillator to settle. This could waste up to 1.2s.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 drivers/clk/at91/sckc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/at91/sckc.c b/drivers/clk/at91/sckc.c
index 60d8225715a2..b1265f2cdae7 100644
--- a/drivers/clk/at91/sckc.c
+++ b/drivers/clk/at91/sckc.c
@@ -69,7 +69,7 @@ static int clk_slow_osc_prepare(struct clk_hw *hw)
 	void __iomem *sckcr = osc->sckcr;
 	u32 tmp = readl(sckcr);
 
-	if (tmp & AT91_SCKC_OSC32BYP)
+	if (tmp & (AT91_SCKC_OSC32BYP | AT91_SCKC_OSC32EN))
 		return 0;
 
 	writel(tmp | AT91_SCKC_OSC32EN, sckcr);
-- 
2.9.3

  parent reply	other threads:[~2016-09-20 20:59 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-09-20 20:58 [PATCH v3 0/5] AT91: sckc improvements Alexandre Belloni
2016-09-20 20:58 ` Alexandre Belloni
2016-09-20 20:58 ` [PATCH v3 1/5] clk: at91: move slow clock controller clocks to sckc.c Alexandre Belloni
2016-09-20 20:58   ` Alexandre Belloni
2016-09-21  0:02   ` Stephen Boyd
2016-09-21  0:02     ` Stephen Boyd
2016-09-21  8:03     ` Alexandre Belloni
2016-09-21  8:03       ` Alexandre Belloni
2016-09-20 20:58 ` [PATCH v3 2/5] clk: at91: Add sama5d4 sckc support Alexandre Belloni
2016-09-20 20:58   ` Alexandre Belloni
2016-09-21  0:04   ` Stephen Boyd
2016-09-21  0:04     ` Stephen Boyd
2016-09-20 20:58 ` Alexandre Belloni [this message]
2016-09-20 20:58   ` [PATCH v3 3/5] clk: at91: sckc: optimize boot time Alexandre Belloni
2016-09-21  0:04   ` Stephen Boyd
2016-09-21  0:04     ` Stephen Boyd
2016-09-20 20:58 ` [PATCH v3 4/5] ARM: dts: at91: sama5d4: use proper sckc compatible Alexandre Belloni
2016-09-20 20:58   ` Alexandre Belloni
2016-09-20 20:58 ` [PATCH v3 5/5] ARM: dts: at91: sama5d2: use correct " Alexandre Belloni
2016-09-20 20:58   ` Alexandre Belloni

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