From b73a19e1609d0f705cbab8014ca17aefe89e4c76 Mon Sep 17 00:00:00 2001
From: Yuri Tikhonov <yur@emcraft.com>
Date: Thu, 20 Mar 2008 17:56:04 +0300
Subject: [PATCH] LWMON5: POST RTC fix

Modify the RTC API to provide one a status for the time reported by
the rtc_get() function:
  0 - a reliable time is guaranteed,
< 0 - a reliable time isn't guaranteed (power fault, clock issues,
      and so on).

The RTC chip drivers are responsible for providing this info if the
corresponding chip supports such functionality. If not - always
report that the time is reliable.

The POST RTC test was modified to detect the RTC faults utilizing
this new rtc_get() feature.

Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
---
 board/bmw/m48t59y.c         |  4 +++-
 board/cray/L1/L1.c          |  4 ++--
 board/etin/debris/phantom.c |  4 +++-
 board/mousse/m48t59y.c      |  4 +++-
 cpu/s3c44b0/cpu.c           |  4 +++-
 drivers/rtc/bfin_rtc.c      |  6 ++++--
 drivers/rtc/ds12887.c       |  4 +++-
 drivers/rtc/ds1302.c        |  6 +++++-
 drivers/rtc/ds1306.c        |  8 ++++++--
 drivers/rtc/ds1307.c        |  6 +++++-
 drivers/rtc/ds1337.c        |  6 +++++-
 drivers/rtc/ds1374.c        | 11 ++++++++---
 drivers/rtc/ds1556.c        |  3 ++-
 drivers/rtc/ds164x.c        |  4 +++-
 drivers/rtc/ds174x.c        |  4 +++-
 drivers/rtc/ds3231.c        |  6 +++++-
 drivers/rtc/isl1208.c       |  6 +++++-
 drivers/rtc/m41t11.c        |  7 ++++++-
 drivers/rtc/m41t60.c        |  6 ++++--
 drivers/rtc/m41t62.c        |  4 +++-
 drivers/rtc/m48t35ax.c      |  4 +++-
 drivers/rtc/max6900.c       |  4 +++-
 drivers/rtc/mc146818.c      |  4 +++-
 drivers/rtc/mcfrtc.c        |  4 +++-
 drivers/rtc/mk48t59.c       |  4 +++-
 drivers/rtc/mpc5xxx.c       |  4 +++-
 drivers/rtc/mpc8xx.c        |  4 +++-
 drivers/rtc/pcf8563.c       |  6 +++++-
 drivers/rtc/rs5c372.c       |  8 ++++----
 drivers/rtc/rx8025.c        | 17 +++++++++++++----
 drivers/rtc/s3c24x0_rtc.c   |  4 +++-
 drivers/rtc/x1205.c         |  4 +++-
 include/rtc.h               |  2 +-
 post/drivers/rtc.c          | 15 +++++++++++++++
 34 files changed, 146 insertions(+), 45 deletions(-)

diff --git a/board/bmw/m48t59y.c b/board/bmw/m48t59y.c
index d72c861a13..a1a85d0fc9 100644
--- a/board/bmw/m48t59y.c
+++ b/board/bmw/m48t59y.c
@@ -278,7 +278,7 @@ void m48_watchdog_arm(int usec)
 /*
  * U-Boot RTC support.
  */
-void
+int
 rtc_get( struct rtc_time *tmp )
 {
 	m48_tod_get(&tmp->tm_year,
@@ -295,6 +295,8 @@ rtc_get( struct rtc_time *tmp )
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec );
 #endif
+
+	return 0;
 }
 
 void
diff --git a/board/cray/L1/L1.c b/board/cray/L1/L1.c
index a0fac7fe5a..5264bafd4b 100644
--- a/board/cray/L1/L1.c
+++ b/board/cray/L1/L1.c
@@ -170,9 +170,9 @@ long int initdram (int board_type)
 
 /* ------------------------------------------------------------------------- */
 /* stubs so we can print dates w/o any nvram RTC.*/
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
-	return;
+	return 0;
 }
 void rtc_set (struct rtc_time *tmp)
 {
diff --git a/board/etin/debris/phantom.c b/board/etin/debris/phantom.c
index 18ab5005ef..263da6b7c9 100644
--- a/board/etin/debris/phantom.c
+++ b/board/etin/debris/phantom.c
@@ -182,7 +182,7 @@ static int get_century_flag(void)
 	return flag;
 }
 
-void rtc_get( struct rtc_time *tmp)
+int rtc_get( struct rtc_time *tmp)
 {
 	if (phantom_flag < 0)
 		phantom_flag = get_phantom_flag();
@@ -250,6 +250,8 @@ void rtc_get( struct rtc_time *tmp)
 		tmp->tm_yday = 0;
 		tmp->tm_isdst= 0;
 	}
+
+	return 0;
 }
 
 void rtc_set( struct rtc_time *tmp )
diff --git a/board/mousse/m48t59y.c b/board/mousse/m48t59y.c
index 37a6244198..2c1e6cf8b7 100644
--- a/board/mousse/m48t59y.c
+++ b/board/mousse/m48t59y.c
@@ -278,7 +278,7 @@ void m48_watchdog_arm(int usec)
 /*
  * U-Boot RTC support.
  */
-void
+int
 rtc_get( struct rtc_time *tmp )
 {
 	m48_tod_get(&tmp->tm_year,
@@ -295,6 +295,8 @@ rtc_get( struct rtc_time *tmp )
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec );
 #endif
+
+	return 0;
 }
 
 void
diff --git a/cpu/s3c44b0/cpu.c b/cpu/s3c44b0/cpu.c
index 5d50b3cea0..eae6adbc0b 100644
--- a/cpu/s3c44b0/cpu.c
+++ b/cpu/s3c44b0/cpu.c
@@ -155,7 +155,7 @@ int dcache_status (void)
 	#define HEX2BCD(x) ((((x) / 10) << 4) + (x) % 10)
 #endif
 
-void rtc_get (struct rtc_time* tm)
+int rtc_get (struct rtc_time* tm)
 {
 	RTCCON |= 1;
 	tm->tm_year  = BCD2HEX(BCDYEAR);
@@ -184,6 +184,8 @@ void rtc_get (struct rtc_time* tm)
 		tm->tm_year += 1900;
 	else
 		tm->tm_year += 2000;
+
+	return 0;
 }
 
 void rtc_set (struct rtc_time* tm)
diff --git a/drivers/rtc/bfin_rtc.c b/drivers/rtc/bfin_rtc.c
index 5755a20bc5..ce4f1711dc 100644
--- a/drivers/rtc/bfin_rtc.c
+++ b/drivers/rtc/bfin_rtc.c
@@ -85,7 +85,7 @@ void rtc_set(struct rtc_time *tmp)
 }
 
 /* Read the time from the RTC_STAT. time_in_seconds is seconds since Jan 1970 */
-void rtc_get(struct rtc_time *tmp)
+int rtc_get(struct rtc_time *tmp)
 {
 	uint32_t cur_rtc_stat;
 	int time_in_sec;
@@ -95,7 +95,7 @@ void rtc_get(struct rtc_time *tmp)
 
 	if (tmp == NULL) {
 		puts("Error getting the date/time\n");
-		return;
+		return -1;
 	}
 
 	wait_for_complete();
@@ -112,6 +112,8 @@ void rtc_get(struct rtc_time *tmp)
 	/* Calculate the total number of seconds since epoch */
 	time_in_sec = (tm_sec) + MIN_TO_SECS(tm_min) + HRS_TO_SECS(tm_hr) + DAYS_TO_SECS(tm_day);
 	to_tm(time_in_sec, tmp);
+
+	return 0;
 }
 
 #endif
diff --git a/drivers/rtc/ds12887.c b/drivers/rtc/ds12887.c
index 84fecf0194..57a446d305 100644
--- a/drivers/rtc/ds12887.c
+++ b/drivers/rtc/ds12887.c
@@ -88,7 +88,7 @@ static unsigned char bin2bcd (unsigned int n)
 
 /* ------------------------------------------------------------------------- */
 
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
 	uchar sec, min, hour, mday, wday, mon, year;
 
@@ -150,6 +150,8 @@ else
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
 #endif
+
+	return 0;
 }
 
 void rtc_set (struct rtc_time *tmp)
diff --git a/drivers/rtc/ds1302.c b/drivers/rtc/ds1302.c
index 55af1302d5..3a856c840a 100644
--- a/drivers/rtc/ds1302.c
+++ b/drivers/rtc/ds1302.c
@@ -253,9 +253,10 @@ rtc_reset(void)
 	/* TODO */
 }
 
-void
+int
 rtc_get(struct rtc_time *tmp)
 {
+	int rel = 0;
 	struct ds1302_st bbclk;
 
 	if(!ds1302_initted) rtc_init();
@@ -265,6 +266,7 @@ rtc_get(struct rtc_time *tmp)
 	if (bbclk.CH) {
 		printf("ds1302: rtc_get: Clock was halted, clock probably "
 			"corrupt\n");
+		rel = -1;
 	}
 
 	tmp->tm_sec=10*bbclk.sec10+bbclk.sec;
@@ -281,6 +283,8 @@ rtc_get(struct rtc_time *tmp)
 	DPRINTF("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec );
+
+	return rel;
 }
 
 void
diff --git a/drivers/rtc/ds1306.c b/drivers/rtc/ds1306.c
index 89e433dabd..1c8ac7f292 100644
--- a/drivers/rtc/ds1306.c
+++ b/drivers/rtc/ds1306.c
@@ -91,7 +91,7 @@ static void init_spi (void);
 /* ------------------------------------------------------------------------- */
 
 /* read clock time from DS1306 and return it in *tmp */
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
 	volatile immap_t *immap = (immap_t *) CFG_IMMR;
 	unsigned char spi_byte;	/* Data Byte */
@@ -141,6 +141,8 @@ void rtc_get (struct rtc_time *tmp)
 	debug ("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 	       tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 	       tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return 0;
 }
 
 /* ------------------------------------------------------------------------- */
@@ -304,7 +306,7 @@ static unsigned char rtc_read (unsigned char reg);
 static void rtc_write (unsigned char reg, unsigned char val);
 
 /* read clock time from DS1306 and return it in *tmp */
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
 	unsigned char sec, min, hour, mday, wday, mon, year;
 
@@ -349,6 +351,8 @@ void rtc_get (struct rtc_time *tmp)
 	debug ("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 	       tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 	       tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return 0;
 }
 
 /* ------------------------------------------------------------------------- */
diff --git a/drivers/rtc/ds1307.c b/drivers/rtc/ds1307.c
index c882d7989a..b20f193b41 100644
--- a/drivers/rtc/ds1307.c
+++ b/drivers/rtc/ds1307.c
@@ -83,8 +83,9 @@ static unsigned bcd2bin (uchar c);
 /*
  * Get the current time from the RTC
  */
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
+	int rel = 0;
 	uchar sec, min, hour, mday, wday, mon, year;
 
 	sec = rtc_read (RTC_SEC_REG_ADDR);
@@ -104,6 +105,7 @@ void rtc_get (struct rtc_time *tmp)
 		/* clear the CH flag */
 		rtc_write (RTC_SEC_REG_ADDR,
 			   rtc_read (RTC_SEC_REG_ADDR) & ~RTC_SEC_BIT_CH);
+		rel = -1;
 	}
 
 	tmp->tm_sec  = bcd2bin (sec & 0x7F);
@@ -119,6 +121,8 @@ void rtc_get (struct rtc_time *tmp)
 	DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return rel;
 }
 
 
diff --git a/drivers/rtc/ds1337.c b/drivers/rtc/ds1337.c
index c636ac5948..50ab44690c 100644
--- a/drivers/rtc/ds1337.c
+++ b/drivers/rtc/ds1337.c
@@ -84,8 +84,9 @@ static unsigned bcd2bin (uchar c);
 /*
  * Get the current time from the RTC
  */
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
+	int rel = 0;
 	uchar sec, min, hour, mday, wday, mon_cent, year, control, status;
 
 	control = rtc_read (RTC_CTL_REG_ADDR);
@@ -107,6 +108,7 @@ void rtc_get (struct rtc_time *tmp)
 		/* clear the OSF flag */
 		rtc_write (RTC_STAT_REG_ADDR,
 			   rtc_read (RTC_STAT_REG_ADDR) & ~RTC_STAT_BIT_OSF);
+		rel = -1;
 	}
 
 	tmp->tm_sec  = bcd2bin (sec & 0x7F);
@@ -122,6 +124,8 @@ void rtc_get (struct rtc_time *tmp)
 	DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return rel;
 }
 
 
diff --git a/drivers/rtc/ds1374.c b/drivers/rtc/ds1374.c
index e773dd9261..f6bb2965a4 100644
--- a/drivers/rtc/ds1374.c
+++ b/drivers/rtc/ds1374.c
@@ -107,8 +107,8 @@ static void rtc_write_raw (uchar reg, uchar val);
 /*
  * Get the current time from the RTC
  */
-void rtc_get (struct rtc_time *tm){
-
+int rtc_get (struct rtc_time *tm){
+	int rel = 0;
 	unsigned long time1, time2;
 	unsigned int limit;
 	unsigned char tmp;
@@ -138,18 +138,23 @@ void rtc_get (struct rtc_time *tm){
 
 	if (time1 != time2) {
 		printf("can't get consistent time from rtc chip\n");
+		rel = -1;
 	}
 
 	DEBUGR ("Get RTC s since 1.1.1970: %d\n", time1);
 
 	to_tm(time1, tm); /* To Gregorian Date */
 
-	if (rtc_read(RTC_SR_ADDR) & RTC_SR_BIT_OSF)
+	if (rtc_read(RTC_SR_ADDR) & RTC_SR_BIT_OSF) {
 		printf ("### Warning: RTC oscillator has stopped\n");
+		rel = -1;
+	}
 
 	DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday,
 		tm->tm_hour, tm->tm_min, tm->tm_sec);
+
+	return rel;
 }
 
 /*
diff --git a/drivers/rtc/ds1556.c b/drivers/rtc/ds1556.c
index 4365cfb981..2c496f510f 100644
--- a/drivers/rtc/ds1556.c
+++ b/drivers/rtc/ds1556.c
@@ -69,7 +69,7 @@ static unsigned bcd2bin(uchar c);
 
 /* ------------------------------------------------------------------------- */
 
-void rtc_get( struct rtc_time *tmp )
+int rtc_get( struct rtc_time *tmp )
 {
 	uchar sec, min, hour;
 	uchar mday, wday, mon, year;
@@ -118,6 +118,7 @@ void rtc_get( struct rtc_time *tmp )
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec );
 #endif
+	return 0;
 }
 
 void rtc_set( struct rtc_time *tmp )
diff --git a/drivers/rtc/ds164x.c b/drivers/rtc/ds164x.c
index bff22b9a05..5943f8711d 100644
--- a/drivers/rtc/ds164x.c
+++ b/drivers/rtc/ds164x.c
@@ -70,7 +70,7 @@ static unsigned bcd2bin(uchar c);
 
 /* ------------------------------------------------------------------------- */
 
-void rtc_get( struct rtc_time *tmp )
+int rtc_get( struct rtc_time *tmp )
 {
 	uchar sec, min, hour;
 	uchar mday, wday, mon, year;
@@ -115,6 +115,8 @@ void rtc_get( struct rtc_time *tmp )
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec );
 #endif
+
+	return 0;
 }
 
 void rtc_set( struct rtc_time *tmp )
diff --git a/drivers/rtc/ds174x.c b/drivers/rtc/ds174x.c
index 5f85a68170..81a9cb3d39 100644
--- a/drivers/rtc/ds174x.c
+++ b/drivers/rtc/ds174x.c
@@ -65,7 +65,7 @@ static unsigned bcd2bin(uchar c);
 
 /* ------------------------------------------------------------------------- */
 
-void rtc_get( struct rtc_time *tmp )
+int rtc_get( struct rtc_time *tmp )
 {
 	uchar sec, min, hour;
 	uchar mday, wday, mon, year;
@@ -142,6 +142,8 @@ void rtc_set( struct rtc_time *tmp )
 
 	/* unlock clock registers after read */
 	rtc_write( RTC_CONTROLA, ( reg_a  & ~RTC_CA_WRITE ));
+
+	return 0;
 }
 
 void rtc_reset (void)
diff --git a/drivers/rtc/ds3231.c b/drivers/rtc/ds3231.c
index fe11b869f5..95cb186348 100644
--- a/drivers/rtc/ds3231.c
+++ b/drivers/rtc/ds3231.c
@@ -86,8 +86,9 @@ static unsigned bcd2bin (uchar c);
 /*
  * Get the current time from the RTC
  */
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
+	int rel = 0;
 	uchar sec, min, hour, mday, wday, mon_cent, year, control, status;
 
 	control = rtc_read (RTC_CTL_REG_ADDR);
@@ -109,6 +110,7 @@ void rtc_get (struct rtc_time *tmp)
 		/* clear the OSF flag */
 		rtc_write (RTC_STAT_REG_ADDR,
 			   rtc_read (RTC_STAT_REG_ADDR) & ~RTC_STAT_BIT_OSF);
+		rel = -1;
 	}
 
 	tmp->tm_sec  = bcd2bin (sec & 0x7F);
@@ -124,6 +126,8 @@ void rtc_get (struct rtc_time *tmp)
 	DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return rel;
 }
 
 
diff --git a/drivers/rtc/isl1208.c b/drivers/rtc/isl1208.c
index d87280229c..3d46fd0653 100644
--- a/drivers/rtc/isl1208.c
+++ b/drivers/rtc/isl1208.c
@@ -73,8 +73,9 @@ static unsigned bcd2bin (uchar c);
  * Get the current time from the RTC
  */
 
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
+	int rel = 0;
 	uchar sec, min, hour, mday, wday, mon, year, status;
 
 	status = rtc_read (RTC_STAT_REG_ADDR);
@@ -94,6 +95,7 @@ void rtc_get (struct rtc_time *tmp)
 		printf ("### Warning: RTC oscillator has stopped\n");
 		rtc_write(RTC_STAT_REG_ADDR,
 			rtc_read(RTC_STAT_REG_ADDR) &~ (RTC_STAT_BIT_BAT|RTC_STAT_BIT_RTCF));
+		rel = -1;
 	}
 
 	tmp->tm_sec  = bcd2bin (sec & 0x7F);
@@ -109,6 +111,8 @@ void rtc_get (struct rtc_time *tmp)
 	DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return rel;
 }
 
 /*
diff --git a/drivers/rtc/m41t11.c b/drivers/rtc/m41t11.c
index 81da33a31e..fce00d9353 100644
--- a/drivers/rtc/m41t11.c
+++ b/drivers/rtc/m41t11.c
@@ -96,14 +96,16 @@ static unsigned char bin2bcd (unsigned int n)
 
 #define M41T11_STORAGE_SZ  (64-REG_CNT)
 
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
+	int rel = 0;
 	uchar data[RTC_REG_CNT];
 
 	i2c_read(CFG_I2C_RTC_ADDR, RTC_SEC_ADDR, 1, data, RTC_REG_CNT);
 
 	if( data[RTC_SEC_ADDR] & 0x80 ){
 		printf( "m41t11 RTC Clock stopped!!!\n" );
+		rel = -1;
 	}
 	tmp->tm_sec  = bcd2bin (data[RTC_SEC_ADDR]  & 0x7F);
 	tmp->tm_min  = bcd2bin (data[RTC_MIN_ADDR]  & 0x7F);
@@ -120,6 +122,7 @@ void rtc_get (struct rtc_time *tmp)
 		i2c_read(CFG_I2C_RTC_ADDR, M41T11_YEAR_DATA, 1, &cent, M41T11_YEAR_SIZE);
 		if( !(data[RTC_HOUR_ADDR] & 0x80) ){
 			printf( "m41t11 RTC: cann't keep track of years without CEB set\n" );
+			rel = -1;
 		}
 		if( (cent & 0x1) != ((data[RTC_HOUR_ADDR]&0x40)>>7) ){
 			/*century flip store off new year*/
@@ -136,6 +139,8 @@ void rtc_get (struct rtc_time *tmp)
 	debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return rel;
 }
 
 void rtc_set (struct rtc_time *tmp)
diff --git a/drivers/rtc/m41t60.c b/drivers/rtc/m41t60.c
index 7c80143e68..8a32ea0748 100644
--- a/drivers/rtc/m41t60.c
+++ b/drivers/rtc/m41t60.c
@@ -170,12 +170,12 @@ static uchar *rtc_validate(void)
 	return data;
 }
 
-void rtc_get(struct rtc_time *tmp)
+int rtc_get(struct rtc_time *tmp)
 {
 	uchar const *const data = rtc_validate();
 
 	if (!data)
-		return;
+		return -1;
 
 	tmp->tm_sec = bcd2bin(data[RTC_SEC] & 0x7F);
 	tmp->tm_min = bcd2bin(data[RTC_MIN] & 0x7F);
@@ -190,6 +190,8 @@ void rtc_get(struct rtc_time *tmp)
 	debug("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 	      tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 	      tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return 0;
 }
 
 void rtc_set(struct rtc_time *tmp)
diff --git a/drivers/rtc/m41t62.c b/drivers/rtc/m41t62.c
index 2bdca3bdf3..cf2a9574a9 100644
--- a/drivers/rtc/m41t62.c
+++ b/drivers/rtc/m41t62.c
@@ -64,7 +64,7 @@
 #define M41T62_FEATURE_HT	(1 << 0)
 #define M41T62_FEATURE_BL	(1 << 1)
 
-void rtc_get(struct rtc_time *tm)
+int rtc_get(struct rtc_time *tm)
 {
 	u8 buf[M41T62_DATETIME_REG_SIZE];
 
@@ -92,6 +92,8 @@ void rtc_get(struct rtc_time *tm)
 	      __FUNCTION__,
 	      tm->tm_sec, tm->tm_min, tm->tm_hour,
 	      tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
+
+	return 0;
 }
 
 void rtc_set(struct rtc_time *tm)
diff --git a/drivers/rtc/m48t35ax.c b/drivers/rtc/m48t35ax.c
index 0a0ffa8aac..be29279d03 100644
--- a/drivers/rtc/m48t35ax.c
+++ b/drivers/rtc/m48t35ax.c
@@ -42,7 +42,7 @@ static unsigned bcd2bin(uchar c);
 
 /* ------------------------------------------------------------------------- */
 
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
 	uchar sec, min, hour, cent_day, date, month, year;
 	uchar ccr;			/* Clock control register */
@@ -83,6 +83,8 @@ void rtc_get (struct rtc_time *tmp)
 	debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return 0;
 }
 
 void rtc_set (struct rtc_time *tmp)
diff --git a/drivers/rtc/max6900.c b/drivers/rtc/max6900.c
index c75a8e04c2..e9979f227d 100644
--- a/drivers/rtc/max6900.c
+++ b/drivers/rtc/max6900.c
@@ -63,7 +63,7 @@ static unsigned char bin2bcd (unsigned int n)
 
 /* ------------------------------------------------------------------------- */
 
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
 	uchar sec, min, hour, mday, wday, mon, cent, year;
 	int retry = 1;
@@ -103,6 +103,8 @@ void rtc_get (struct rtc_time *tmp)
 	debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return 0;
 }
 
 void rtc_set (struct rtc_time *tmp)
diff --git a/drivers/rtc/mc146818.c b/drivers/rtc/mc146818.c
index ab377ed73e..70f7017a3f 100644
--- a/drivers/rtc/mc146818.c
+++ b/drivers/rtc/mc146818.c
@@ -57,7 +57,7 @@ static unsigned bcd2bin(uchar c);
 
 /* ------------------------------------------------------------------------- */
 
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
 	uchar sec, min, hour, mday, wday, mon, year;
   /* here check if rtc can be accessed */
@@ -101,6 +101,8 @@ void rtc_get (struct rtc_time *tmp)
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
 #endif
+
+	return 0;
 }
 
 void rtc_set (struct rtc_time *tmp)
diff --git a/drivers/rtc/mcfrtc.c b/drivers/rtc/mcfrtc.c
index 27386e586a..d235d10f28 100644
--- a/drivers/rtc/mcfrtc.c
+++ b/drivers/rtc/mcfrtc.c
@@ -39,7 +39,7 @@
 #define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
 #define	STARTOFTIME		1970
 
-void rtc_get(struct rtc_time *tmp)
+int rtc_get(struct rtc_time *tmp)
 {
 	volatile rtc_t *rtc = (rtc_t *) (CFG_MCFRTC_BASE);
 
@@ -64,6 +64,8 @@ void rtc_get(struct rtc_time *tmp)
 	       tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 	       tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
 #endif
+
+	return 0;
 }
 
 void rtc_set(struct rtc_time *tmp)
diff --git a/drivers/rtc/mk48t59.c b/drivers/rtc/mk48t59.c
index bacdb5b70b..59813998ed 100644
--- a/drivers/rtc/mk48t59.c
+++ b/drivers/rtc/mk48t59.c
@@ -135,7 +135,7 @@ void nvram_write(short dest, const void *src, size_t count)
 
 /* ------------------------------------------------------------------------- */
 
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
 	uchar save_ctrl_a;
 	uchar sec, min, hour, mday, wday, mon, year;
@@ -183,6 +183,8 @@ void rtc_get (struct rtc_time *tmp)
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
 #endif
+
+	return 0;
 }
 
 void rtc_set (struct rtc_time *tmp)
diff --git a/drivers/rtc/mpc5xxx.c b/drivers/rtc/mpc5xxx.c
index 216386aba0..a6555f5eb6 100644
--- a/drivers/rtc/mpc5xxx.c
+++ b/drivers/rtc/mpc5xxx.c
@@ -55,7 +55,7 @@ typedef struct rtc5200 {
 /*****************************************************************************
  * get time
  *****************************************************************************/
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
 	RTC5200	*rtc = (RTC5200 *) (CFG_MBAR+0x800);
 	ulong time, date, time2;
@@ -81,6 +81,8 @@ void rtc_get (struct rtc_time *tmp)
 	debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return 0;
 }
 
 /*****************************************************************************
diff --git a/drivers/rtc/mpc8xx.c b/drivers/rtc/mpc8xx.c
index 8d10c0e465..057547bc3c 100644
--- a/drivers/rtc/mpc8xx.c
+++ b/drivers/rtc/mpc8xx.c
@@ -35,7 +35,7 @@
 
 /* ------------------------------------------------------------------------- */
 
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
 	volatile immap_t *immr = (immap_t *)CFG_IMMR;
 	ulong tim;
@@ -47,6 +47,8 @@ void rtc_get (struct rtc_time *tmp)
 	debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return 0;
 }
 
 void rtc_set (struct rtc_time *tmp)
diff --git a/drivers/rtc/pcf8563.c b/drivers/rtc/pcf8563.c
index 2d73d5d7ef..c384975f35 100644
--- a/drivers/rtc/pcf8563.c
+++ b/drivers/rtc/pcf8563.c
@@ -41,8 +41,9 @@ static unsigned bcd2bin(uchar c);
 
 /* ------------------------------------------------------------------------- */
 
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
+	int rel = 0;
 	uchar sec, min, hour, mday, wday, mon_cent, year;
 
 	sec	= rtc_read (0x02);
@@ -65,6 +66,7 @@ void rtc_get (struct rtc_time *tmp)
 
 	if (sec & 0x80) {
 		puts ("### Warning: RTC Low Voltage - date/time not reliable\n");
+		rel = -1;
 	}
 
 	tmp->tm_sec  = bcd2bin (sec  & 0x7F);
@@ -80,6 +82,8 @@ void rtc_get (struct rtc_time *tmp)
 	debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return rel;
 }
 
 void rtc_set (struct rtc_time *tmp)
diff --git a/drivers/rtc/rs5c372.c b/drivers/rtc/rs5c372.c
index 3d1346eaa7..1c9b752429 100644
--- a/drivers/rtc/rs5c372.c
+++ b/drivers/rtc/rs5c372.c
@@ -166,7 +166,7 @@ rs5c372_convert_to_time(struct rtc_time *dt, unsigned char *buf)
 /*
  * Get the current time from the RTC
  */
-void
+int
 rtc_get (struct rtc_time *tmp)
 {
 	unsigned char buf[RS5C372_RAM_SIZE];
@@ -176,7 +176,7 @@ rtc_get (struct rtc_time *tmp)
 		rs5c372_enable();
 
 	if (!setup_done)
-		return;
+		return -1;
 
 	memset(buf, 0, sizeof(buf));
 
@@ -184,12 +184,12 @@ rtc_get (struct rtc_time *tmp)
 	ret = rs5c372_readram(buf, RS5C372_RAM_SIZE);
 	if (ret != 0) {
 		printf("%s: failed\n", __FUNCTION__);
-		return;
+		return -1;
 	}
 
 	rs5c372_convert_to_time(tmp, buf);
 
-	return;
+	return 0;
 }
 
 /*
diff --git a/drivers/rtc/rx8025.c b/drivers/rtc/rx8025.c
index 9122f12fc0..64eafe5c37 100644
--- a/drivers/rtc/rx8025.c
+++ b/drivers/rtc/rx8025.c
@@ -96,8 +96,9 @@ static unsigned bcd2bin (uchar c);
 /*
  * Get the current time from the RTC
  */
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
+	int rel = 0;
 	uchar sec, min, hour, mday, wday, mon, year, ctl2;
 	uchar buf[16];
 
@@ -118,14 +119,20 @@ void rtc_get (struct rtc_time *tmp)
 
 	/* dump status */
 	ctl2 = rtc_read(RTC_CTL2_REG_ADDR);
-	if (ctl2 & RTC_CTL2_BIT_PON)
+	if (ctl2 & RTC_CTL2_BIT_PON) {
 		printf("RTC: power-on detected\n");
+		rel = -1;
+	}
 
-	if (ctl2 & RTC_CTL2_BIT_VDET)
+	if (ctl2 & RTC_CTL2_BIT_VDET) {
 		printf("RTC: voltage drop detected\n");
+		rel = -1;
+	}
 
-	if (!(ctl2 & RTC_CTL2_BIT_XST))
+	if (!(ctl2 & RTC_CTL2_BIT_XST)) {
 		printf("RTC: oscillator stop detected\n");
+		rel = -1;
+	}
 
 	tmp->tm_sec  = bcd2bin (sec & 0x7F);
 	tmp->tm_min  = bcd2bin (min & 0x7F);
@@ -140,6 +147,8 @@ void rtc_get (struct rtc_time *tmp)
 	DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+	return rel;
 }
 
 /*
diff --git a/drivers/rtc/s3c24x0_rtc.c b/drivers/rtc/s3c24x0_rtc.c
index 7f8b4fad0d..358aef751c 100644
--- a/drivers/rtc/s3c24x0_rtc.c
+++ b/drivers/rtc/s3c24x0_rtc.c
@@ -70,7 +70,7 @@ static unsigned char bin2bcd (unsigned int n)
 
 /* ------------------------------------------------------------------------- */
 
-void rtc_get (struct rtc_time *tmp)
+int rtc_get (struct rtc_time *tmp)
 {
 	S3C24X0_RTC * const rtc = S3C24X0_GetBase_RTC();
 	uchar sec, min, hour, mday, wday, mon, year;
@@ -131,6 +131,8 @@ void rtc_get (struct rtc_time *tmp)
 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
 #endif
+
+	return 0;
 }
 
 void rtc_set (struct rtc_time *tmp)
diff --git a/drivers/rtc/x1205.c b/drivers/rtc/x1205.c
index 319f0512ca..0e1813917f 100644
--- a/drivers/rtc/x1205.c
+++ b/drivers/rtc/x1205.c
@@ -104,7 +104,7 @@ static void rtc_write(int reg, u8 val)
  * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch
  * Epoch is initialized as 2000. Time is set to UTC.
  */
-void rtc_get(struct rtc_time *tm)
+int rtc_get(struct rtc_time *tm)
 {
 	u8 buf[8];
 
@@ -130,6 +130,8 @@ void rtc_get(struct rtc_time *tm)
 	      __FUNCTION__,
 	      tm->tm_sec, tm->tm_min, tm->tm_hour,
 	      tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
+
+	return 0;
 }
 
 void rtc_set(struct rtc_time *tm)
diff --git a/include/rtc.h b/include/rtc.h
index 15f3571d76..2995144a0d 100644
--- a/include/rtc.h
+++ b/include/rtc.h
@@ -52,7 +52,7 @@ struct rtc_time {
 	int tm_isdst;
 };
 
-void rtc_get (struct rtc_time *);
+int rtc_get (struct rtc_time *);
 void rtc_set (struct rtc_time *);
 void rtc_reset (void);
 
diff --git a/post/drivers/rtc.c b/post/drivers/rtc.c
index 7d4f9b88ee..e3da5e64ce 100644
--- a/post/drivers/rtc.c
+++ b/post/drivers/rtc.c
@@ -28,6 +28,8 @@
  *
  * The Real Time Clock (RTC) operation is verified by this test.
  * The following features are verified:
+ *   o) RTC Power Fault
+ *	This is verified by analyzing the rtc_get() return status.
  *   o) Time uniformity
  *      This is verified by reading RTC in polling within
  *      a short period of time.
@@ -96,6 +98,10 @@ int rtc_post_test (int flags)
 	unsigned int ynl = 1999;
 	unsigned int yl = 2000;
 	unsigned int skipped = 0;
+	int reliable;
+
+	/* Time reliability */
+	reliable = rtc_get (&svtm);
 
 	/* Time uniformity */
 	if (rtc_post_skip (&diff) != 0) {
@@ -176,6 +182,15 @@ int rtc_post_test (int flags)
 	}
 	rtc_post_restore (&svtm, skipped);
 
+	/* If come here, then RTC operates correcty, check the correctness
+	 * of the time it reports.
+	 */
+	if (reliable < 0) {
+		post_log ("RTC Time is not reliable! Power fault? \n");
+
+		return -1;
+	}
+
 	return 0;
 }
 
-- 
2.39.5