From: Shawn Guo <shawn.guo@linaro.org>
Date: Wed, 30 Oct 2013 07:12:55 +0000 (+0800)
Subject: ARM: imx: add sleep for pllv3 relock
X-Git-Tag: firefly_0821_release~176^2~4691^2~32^2~4
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=322503a15740bd9383bb4ed452e5dd5a40598170;p=firefly-linux-kernel-4.4.55.git

ARM: imx: add sleep for pllv3 relock

The pllv3 relock time varies in the range of 50us ~ 500us, depending on
the specific PLL type, e.g. 50us for ARM PLL and 450us for Audio/Video
PLL.  Let's add a usleep_range() call instead of doing busy wait during
relock.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
---

diff --git a/arch/arm/mach-imx/clk-pllv3.c b/arch/arm/mach-imx/clk-pllv3.c
index f6640b6a7b31..c9ca19184420 100644
--- a/arch/arm/mach-imx/clk-pllv3.c
+++ b/arch/arm/mach-imx/clk-pllv3.c
@@ -12,6 +12,7 @@
 
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
+#include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/jiffies.h>
@@ -66,6 +67,7 @@ static int clk_pllv3_prepare(struct clk_hw *hw)
 			break;
 		if (time_after(jiffies, timeout))
 			break;
+		usleep_range(50, 500);
 	} while (1);
 
 	if (readl_relaxed(pll->base) & BM_PLL_LOCK)