From: Lokesh Vutla <lokeshvutla@ti.com>
Date: Sat, 16 Mar 2013 06:16:41 +0000 (+0530)
Subject: memory: emif: Fix the lpmode timeout calculation
X-Git-Tag: accepted/tizen/common/20141203.182822~2439^2~75
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=0a5f19cf303ea9cc9bf89a42960a69db4ea3c35b;p=platform%2Fkernel%2Flinux-arm64.git

memory: emif: Fix the lpmode timeout calculation

The driver tries to round up the specified timeout cycles to
the next power of 2 value. This should be done defore updating
timeout variable.
Correcting this here.

Reported-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/memory/emif.c b/drivers/memory/emif.c
index ecbc1a9..897c39a 100644
--- a/drivers/memory/emif.c
+++ b/drivers/memory/emif.c
@@ -728,13 +728,17 @@ static u32 get_pwr_mgmt_ctrl(u32 freq, struct emif_data *emif, u32 ip_rev)
 	/* Timeout based on DDR frequency */
 	timeout = freq >= freq_threshold ? timeout_perf : timeout_pwr;
 
-	/* The value to be set in register is "log2(timeout) - 3" */
+	/*
+	 * The value to be set in register is "log2(timeout) - 3"
+	 * if timeout < 16 load 0 in register
+	 * if timeout is not a power of 2, round to next highest power of 2
+	 */
 	if (timeout < 16) {
 		timeout = 0;
 	} else {
-		timeout = __fls(timeout) - 3;
 		if (timeout & (timeout - 1))
-			timeout++;
+			timeout <<= 1;
+		timeout = __fls(timeout) - 3;
 	}
 
 	switch (lpmode) {