From da57bddb827ff0da2eb8da33b7081ff56d9dea2d Mon Sep 17 00:00:00 2001
From: Justin Waters <justin.waters@timesys.com>
Date: Wed, 19 Dec 2012 11:13:24 -0500
Subject: vybrid: Fix hardware clock drift

We must enable the external 32kHz oscillator in order to work
around a known clock drift issue with the internal 32kHz oscillator.

This fixes the Linux kernel system clock drift.

Signed-off-by: Anthony Huereca <B04178@freescale.com>
Signed-off-by: Jiri Kotzian <B36968@freescale.com>
Signed-off-by: Justin Waters <justin.waters@timesys.com>
---
 board/freescale/vybrid/vybrid.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

(limited to 'board')

diff --git a/board/freescale/vybrid/vybrid.c b/board/freescale/vybrid/vybrid.c
index a1507e170b..c9b423888f 100644
--- a/board/freescale/vybrid/vybrid.c
+++ b/board/freescale/vybrid/vybrid.c
@@ -30,6 +30,7 @@
 #include <asm/errno.h>
 #include <asm/arch/sys_proto.h>
 #include <asm/arch/crm_regs.h>
+#include <asm/arch/scsc_regs.h>
 #include <i2c.h>
 #include <mmc.h>
 #include <fsl_esdhc.h>
@@ -512,9 +513,23 @@ int board_early_init_f(void)
 
 int board_init(void)
 {
+	u32 temp;
+	struct vybrid_scsc_reg *scsc = (struct vybrid_scsc_reg *)SCSCM_BASE_ADDR;
+
 	/* address of boot parameters */
 	gd->bd->bi_boot_params = CONFIG_SYS_SDRAM_BASE + 0x100;
 
+	/*
+	 * Enable external 32K Oscillator
+	 *
+	 * The internal clock experiences significant drift
+         * so we must use the external oscillator in order
+	 * to maintain correct time in the hwclock
+	 */
+	temp = __raw_readl(&scsc->sosc_ctr);
+	temp |= VYBRID_SCSC_SICR_CTR_SOSC_EN;
+	__raw_writel(temp, &scsc->sosc_ctr);
+
 	return 0;
 }
 
-- 
cgit v1.2.3