From: Ranjani Vaidyanathan <ra5478@freescale.com>
Date: Mon, 7 May 2012 19:28:49 +0000 (-0500)
Subject: ENGR00209621 MX6-Fixed random CON_ACK stall
X-Git-Tag: v3.0.35-fsl~1008
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=891a84da4672cb5b06823901ebfed7b2e7cae3ab;p=karo-tx-linux.git

ENGR00209621 MX6-Fixed random CON_ACK stall

DLL ON/OFF code randomly hangs waiting for the CON_ACK bit
to be set when a CON_REQ is asserted.
Fix this by adding a delay after the MMDC automatic power savings
mode is disabled.

Signed-off-by: Ranjani Vaidyanathan <ra5478@freescale.com>
---

diff --git a/arch/arm/mach-mx6/mx6_ddr_freq.S b/arch/arm/mach-mx6/mx6_ddr_freq.S
index 80600dd0163b..fbaa44df8cdc 100644
--- a/arch/arm/mach-mx6/mx6_ddr_freq.S
+++ b/arch/arm/mach-mx6/mx6_ddr_freq.S
@@ -389,6 +389,19 @@ ddr_freq_change:
 	bic    r0, r0, #0xff00
 	str    r0, [r5, #0x4]
 
+/* Delay for a while */
+	ldr      r1, =4
+delay1:
+	ldr      r2, =0
+cont1:
+	ldr      r0, [r5, r2]
+	add     r2, r2, #4
+	cmp    r2, #16
+	bne     cont1
+	sub     r1, r1, #1
+	cmp    r1, #0
+	bgt     delay1
+
 	/* set CON_REG */
 	ldr     r0, =0x8000
 	str     r0, [r5, #0x1C]