Clone a tag rather than SeaBIOS stable branch HEAD

[coreboot.git] / payloads / libpayload / drivers / nvram.c

diff --git a/payloads/libpayload/drivers/nvram.c b/payloads/libpayload/drivers/nvram.c
index 9196d80b86983e2276e017f5e67a1447537236de..86ff6704256bc00a0b46e66649d1f800c89031b2 100644 (file)
--- a/payloads/libpayload/drivers/nvram.c
+++ b/payloads/libpayload/drivers/nvram.c
@@ -39,7 +39,7 @@
  * http://bochs.sourceforge.net/techspec/CMOS-reference.txt
  * http://www.bioscentral.com/misc/cmosmap.htm
  */
-
+#include <libpayload-config.h>
 #include <libpayload.h>
 
 
@@ -68,7 +68,7 @@
 
 /**
  * Read a byte from the specified NVRAM address.
- * 
+ *
  * @param addr The NVRAM address to read a byte from.
  * @return The byte at the given NVRAM address.
  */
@@ -82,7 +82,7 @@ u8 nvram_read(u8 addr)
 
 /**
  * Write a byte to the specified NVRAM address.
- * 
+ *
  * @param val The byte to write to NVRAM.
  * @param addr The NVRAM address to write to.
  */
@@ -93,3 +93,43 @@ void nvram_write(u8 val, u8 addr)
        outb(addr, rtc_port);
        outb(val, rtc_port + 1);
 }
+
+/**
+ * Return 1 if the NVRAM is currently updating and a 0 otherwise
+ * @return A 1 if the NVRAM is updating and 0 otherwise
+ */
+
+int nvram_updating(void)
+{
+       return (nvram_read(NVRAM_RTC_FREQ_SELECT) & NVRAM_RTC_UIP) ? 1 : 0;
+}
+
+/**
+ * Get the current time and date from the RTC
+ *
+ * @param time A pointer to a broken-down time structure
+ */
+void rtc_read_clock(struct tm *time)
+{
+       memset(time, 0, sizeof(*time));
+
+       while(nvram_updating());
+
+       time->tm_mon = bcd2dec(nvram_read(NVRAM_RTC_MONTH)) - 1;
+       time->tm_sec = bcd2dec(nvram_read(NVRAM_RTC_SECONDS));
+       time->tm_min = bcd2dec(nvram_read(NVRAM_RTC_MINUTES));
+       time->tm_mday = bcd2dec(nvram_read(NVRAM_RTC_DAY));
+       time->tm_hour = bcd2dec(nvram_read(NVRAM_RTC_HOURS));
+
+       /* Instead of finding the century register,
+          we just make an assumption that if the year value is
+          less then 80, then it is 2000+
+       */
+
+       time->tm_year = bcd2dec(nvram_read(NVRAM_RTC_YEAR));
+
+       if (time->tm_year < 80)
+               time->tm_year += 100;
+}
+
+