From a5f35d63f2ec0f95162da924d346922d5888aa38 Mon Sep 17 00:00:00 2001
From: Bo Shen <voice.shen@atmel.com>
Date: Fri, 24 Oct 2014 16:13:25 +0800
Subject: [PATCH] ARM: atmel: spl: make initialization more stable
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We need to make sure the main clock ready field in MCFR is set
after switch to main crystal oscillator.

Signed-off-by: Bo Shen <voice.shen@atmel.com>
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
---
 arch/arm/cpu/at91-common/spl.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm/cpu/at91-common/spl.c b/arch/arm/cpu/at91-common/spl.c
index 674a47061e..57fb04106d 100644
--- a/arch/arm/cpu/at91-common/spl.c
+++ b/arch/arm/cpu/at91-common/spl.c
@@ -50,6 +50,10 @@ static void switch_to_main_crystal_osc(void)
 	while (!(readl(&pmc->sr) & AT91_PMC_IXR_MOSCSELS))
 		;
 
+	/* Wait until MAINRDY field is set to make sure main clock is stable */
+	while (!(readl(&pmc->mcfr) & AT91_PMC_MAINRDY))
+		;
+
 	tmp = readl(&pmc->mor);
 	tmp &= ~AT91_PMC_MOR_MOSCRCEN;
 	tmp &= ~AT91_PMC_MOR_KEY(0xff);
-- 
2.39.5