Stefan Reinauer (stefan.reinauer@coreboot.org) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/1697
-gerrit
commit 63c1148e53397d73c7c61bc5784349b6a4650d91 Author: Vincent Palatin vpalatin@chromium.org Date: Tue Aug 7 17:03:40 2012 -0700
rtc: erase CMOS memory after power failure
When a power failure happens on the RTC rail, the CMOS memory (including the RTC registers) is filled with garbage. So, we erase the full first bank (112 bytes) and we reset the RTC date to the build date.
To test, disconnect the CMOS battery to produce an RTC power failure, then boot the machine and observe the RTC date is the build date using "cat /sys/class/rtc/rtc0/date"
Change-Id: I684bb3ad5079f96825555d4ed84dc0f7914e9884 Signed-off-by: Vincent Palatin vpalatin@chromium.org --- Makefile.inc | 4 ++++ src/drivers/pc80/mc146818rtc.c | 34 ++++++++++++++++++++-------------- 2 files changed, 24 insertions(+), 14 deletions(-)
diff --git a/Makefile.inc b/Makefile.inc index 3f079cd..7d32a96 100644 --- a/Makefile.inc +++ b/Makefile.inc @@ -179,6 +179,10 @@ $(obj)/build.h: .xcompile printf "#define COREBOOT_VERSION "$(KERNELVERSION)"\n" >> $(obj)/build.ht printf "#define COREBOOT_EXTRA_VERSION "$(COREBOOT_EXTRA_VERSION)"\n" >> $(obj)/build.ht printf "#define COREBOOT_BUILD "`LANG= date`"\n" >> $(obj)/build.ht + printf "#define COREBOOT_BUILD_YEAR `LANG= date +"%-y"`\n" >> $(obj)/build.ht + printf "#define COREBOOT_BUILD_MONTH `LANG= date +"%-m"` \n" >> $(obj)/build.ht + printf "#define COREBOOT_BUILD_DAY `LANG= date +"%-d"`\n" >> $(obj)/build.ht + printf "#define COREBOOT_BUILD_WEEKDAY `LANG= date +"%-u"`\n" >> $(obj)/build.ht printf "#define COREBOOT_DMI_DATE "`LANG= date +"%m/%d/%Y"`"\n" >> $(obj)/build.ht printf "\n" >> $(obj)/build.ht printf "#define COREBOOT_COMPILER "$(shell LANG= $(CC) --version | head -n1)"\n" >> $(obj)/build.ht diff --git a/src/drivers/pc80/mc146818rtc.c b/src/drivers/pc80/mc146818rtc.c index efeb378..d832544 100644 --- a/src/drivers/pc80/mc146818rtc.c +++ b/src/drivers/pc80/mc146818rtc.c @@ -1,4 +1,5 @@ #include <stdint.h> +#include <build.h> #include <console/console.h> #include <pc80/mc146818rtc.h> #include <boot/coreboot_tables.h> @@ -79,15 +80,14 @@
static void rtc_update_cmos_date(u8 has_century) { - /* Now setup a default date of Sat 1 January 2000 */ - /* TODO: Set the time as building time? Is it reasonable? */ + /* Now setup a default date equals to the build date */ 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); + cmos_write(COREBOOT_BUILD_WEEKDAY, RTC_CLK_DAYOFWEEK); + cmos_write(COREBOOT_BUILD_DAY, RTC_CLK_DAYOFMONTH); + cmos_write(COREBOOT_BUILD_MONTH, RTC_CLK_MINUTE); + cmos_write(COREBOOT_BUILD_YEAR, RTC_CLK_YEAR); if (has_century) cmos_write(0x20, RTC_CLK_ALTCENTURY); }
@@ -129,9 +129,10 @@ static void rtc_set_checksum(int range_start, int range_end, int cks_loc)
void rtc_init(int invalid) { + int cmos_invalid = 0; + int checksum_invalid = 0; #if CONFIG_USE_OPTION_TABLE unsigned char x; - int cmos_invalid, checksum_invalid; #endif
printk(BIOS_DEBUG, "RTC Init\n"); @@ -146,17 +147,18 @@ void rtc_init(int invalid) PC_CKS_RANGE_END,PC_CKS_LOC);
#define CLEAR_CMOS 0 +#else +#define CLEAR_CMOS 1 +#endif + if (invalid || cmos_invalid || checksum_invalid) { - printk(BIOS_WARNING, "RTC:%s%s%s%s\n", - invalid?" Clear requested":"", - cmos_invalid?" Power Problem":"", - checksum_invalid?" Checksum invalid":"", - CLEAR_CMOS?" zeroing cmos":""); #if CLEAR_CMOS + int i; + cmos_write(0, 0x01); cmos_write(0, 0x03); cmos_write(0, 0x05); - for(i = 10; i < 48; i++) { + for(i = 10; i < 128; i++) { cmos_write(0, i); }
@@ -164,8 +166,12 @@ void rtc_init(int invalid) rtc_update_cmos_date(RTC_HAS_NO_ALTCENTURY); } #endif + printk(BIOS_WARNING, "RTC:%s%s%s%s\n", + invalid?" Clear requested":"", + cmos_invalid?" Power Problem":"", + checksum_invalid?" Checksum invalid":"", + CLEAR_CMOS?" zeroing cmos":""); } -#endif
/* Setup the real time clock */ cmos_write(RTC_CONTROL_DEFAULT, RTC_CONTROL);
-
Stefan Reinauer