[coreboot] Patch set updated for coreboot: 41b3dd0 RTC: Add a routine to check if the CMOS date is valid
Zheng Bao (zheng.bao@amd.com)
gerrit at coreboot.org
Thu Aug 2 08:46:34 CEST 2012
Zheng Bao (zheng.bao at amd.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/1389
-gerrit
commit 41b3dd08ffc03c4b434cad25256b03bfb89a0107
Author: zbao <fishbaozi at gmail.com>
Date: Thu Aug 2 16:30:23 2012 +0800
RTC: Add a routine to check if the CMOS date is valid
If the CMOS is cleared or someone writes some random date/time
on purpose, the CMOS date register has a invalid date. This will
hurts some OS, like Windows 7, which hangs at MS logo forever.
When we detect that, we need to write a reasonable date in CMOS.
Change-Id: Ic1c7a2d60e711265686441c77bdf7891a7efb42e
Signed-off-by: Zheng Bao <zheng.bao at amd.com>
Signed-off-by: zbao <fishbaozi at gmail.com>
---
src/drivers/pc80/mc146818rtc.c | 42 +++++++++++++++++++++++++++++++++------
src/include/pc80/mc146818rtc.h | 5 ++++
2 files changed, 40 insertions(+), 7 deletions(-)
diff --git a/src/drivers/pc80/mc146818rtc.c b/src/drivers/pc80/mc146818rtc.c
index 99d670d..60cd14c 100644
--- a/src/drivers/pc80/mc146818rtc.c
+++ b/src/drivers/pc80/mc146818rtc.c
@@ -148,13 +148,13 @@ void rtc_init(int invalid)
if (cmos_invalid) {
/* Now setup a default date of Sat 1 January 2000 */
- cmos_write(0, 0x00); /* seconds */
- cmos_write(0, 0x02); /* minutes */
- cmos_write(1, 0x04); /* hours */
- cmos_write(7, 0x06); /* day of week */
- cmos_write(1, 0x07); /* day of month */
- cmos_write(1, 0x08); /* month */
- cmos_write(0, 0x09); /* year */
+ cmos_write(0, RTC_CLK_SECOND);
+ cmos_write(0, RTC_CLK_MINUTE);
+ cmos_write(1, RTC_CLK_HOUR);
+ cmos_write(7, RTC_CLK_DAYOFWEEK);
+ cmos_write(1, RTC_CLK_DAYOFMONTH);
+ cmos_write(1, RTC_CLK_MINUTE);
+ cmos_write(0, RTC_CLK_YEAR);
}
#endif
}
@@ -338,3 +338,31 @@ int set_option(const char *name, void *value)
return 0;
}
#endif /* CONFIG_USE_OPTION_TABLE */
+
+/*
+ * If the CMOS is cleared, the rtc_reg has the invalid date. That
+ * hurts some OSes. Even if we don't set USE_OPTION_TABLE, we need
+ * to make sure the date is valid.
+ */
+void rtc_check_update_coms_date(u8 has_century)
+{
+ u8 year, century;
+
+ /* Note: We need to check if the hardware supports RTC_CLK_ALTCENTURY. */
+ century = has_century ? cmos_read(RTC_CLK_ALTCENTURY) : 0;
+ year = cmos_read(RTC_CLK_YEAR);
+
+ /* TODO: If century is 0xFF, 100% that the cmos is cleared.
+ * Other than that, so far rtc_year is the only entry to check if the date is valid. */
+ if (century > 0x99 || year > 0x99) { /* Invalid date */
+ /* Now setup a default date of Sat 1 January 2000 */
+ cmos_write(0, RTC_CLK_SECOND);
+ cmos_write(0, RTC_CLK_MINUTE);
+ cmos_write(1, RTC_CLK_HOUR);
+ cmos_write(7, RTC_CLK_DAYOFWEEK);
+ cmos_write(1, RTC_CLK_DAYOFMONTH);
+ cmos_write(1, RTC_CLK_MINUTE);
+ cmos_write(0, RTC_CLK_YEAR);
+ has_century ? cmos_write(0x20, RTC_CLK_ALTCENTURY) : NULL;
+ }
+}
diff --git a/src/include/pc80/mc146818rtc.h b/src/include/pc80/mc146818rtc.h
index 9f18ba4..58b307e 100644
--- a/src/include/pc80/mc146818rtc.h
+++ b/src/include/pc80/mc146818rtc.h
@@ -87,6 +87,10 @@
#define RTC_CLK_DAYOFMONTH 7
#define RTC_CLK_MONTH 8
#define RTC_CLK_YEAR 9
+#define RTC_CLK_ALTCENTURY 0x32
+
+#define RTC_HAS_ALTCENTURY 1
+#define RTC_HAS_NO_ALTCENTURY 0
/* On PCs, the checksum is built only over bytes 16..45 */
#define PC_CKS_RANGE_START 16
@@ -136,6 +140,7 @@ static inline void cmos_write32(u8 offset, u32 value)
#if !defined(__ROMCC__)
void rtc_init(int invalid);
+void rtc_check_update_coms_date(u8 has_century);
#if CONFIG_USE_OPTION_TABLE
int set_option(const char *name, void *val);
int get_option(void *dest, const char *name);
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