Add logic to check uninitialized RTC value in PcRtc driver in MdeModulePkg.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@5281 6f19259b-4bc3-4df7-8a09-765794883524

2 files changed, 96 insertions, 56 deletions

diff --git a/MdeModulePkg/Universal/PcatRealTimeClockRuntimeDxe/PcRtc.c b/MdeModulePkg/Universal/PcatRealTimeClockRuntimeDxe/PcRtc.c
index c9bf401e1c..057c0407b2 100644
--- a/MdeModulePkg/Universal/PcatRealTimeClockRuntimeDxe/PcRtc.c
+++ b/MdeModulePkg/Universal/PcatRealTimeClockRuntimeDxe/PcRtc.c
@@ -165,16 +165,12 @@ Returns:
   Time.Month  = RtcRead (RTC_ADDRESS_MONTH);

   Time.Year   = RtcRead (RTC_ADDRESS_YEAR);

 

-  ConvertRtcTimeToEfiTime (&Time, RegisterB);

-

   if (RtcTestCenturyRegister () == EFI_SUCCESS) {

-    Century = BcdToDecimal8 ((UINT8) (RtcRead (RTC_ADDRESS_CENTURY) & 0x7f));

+    Century = (UINT8) (RtcRead (RTC_ADDRESS_CENTURY) & 0x7f);

   } else {

-    Century = BcdToDecimal8 (RtcRead (RTC_ADDRESS_CENTURY));

+    Century = RtcRead (RTC_ADDRESS_CENTURY);

   }

 

-  Time.Year = (UINT16) (Century * 100 + Time.Year);

-

   //

   // Set RTC configuration after get original time

   // The value of bit AIE should be reserved.

@@ -186,13 +182,18 @@ Returns:
   //

   //BugBug: the EfiAtRuntime should be encapsulated in EfiAcquireLock or

   //        provide a new instance for EfiAcquireLock, say, RtEfiAcquireLock

+  //

   if (!EfiAtRuntime ()) {

   EfiReleaseLock (&Global->RtcLock);

   }

+ 

   //

   // Validate time fields

   //

-  Status = RtcTimeFieldsValid (&Time);

+  Status = ConvertRtcTimeToEfiTime (&Time, Century, RegisterB);

+  if (!EFI_ERROR (Status)) {

+    Status = RtcTimeFieldsValid (&Time);

+  }

   if (EFI_ERROR (Status)) {

     Time.Second = RTC_INIT_SECOND;

     Time.Minute = RTC_INIT_MINUTE;

@@ -295,16 +296,12 @@ Routine Description:
   Time->Month   = RtcRead (RTC_ADDRESS_MONTH);

   Time->Year    = RtcRead (RTC_ADDRESS_YEAR);

 

-  ConvertRtcTimeToEfiTime (Time, RegisterB);

-

   if (RtcTestCenturyRegister () == EFI_SUCCESS) {

-    Century = BcdToDecimal8 ((UINT8) (RtcRead (RTC_ADDRESS_CENTURY) & 0x7f));

+    Century = (UINT8) (RtcRead (RTC_ADDRESS_CENTURY) & 0x7f);

   } else {

-    Century = BcdToDecimal8 (RtcRead (RTC_ADDRESS_CENTURY));

+    Century = RtcRead (RTC_ADDRESS_CENTURY);

   }

 

-  Time->Year = (UINT16) (Century * 100 + Time->Year);

-

   //

   // Release RTC Lock.

   //

@@ -322,7 +319,10 @@ Routine Description:
   //

   // Make sure all field values are in correct range

   //

-  Status = RtcTimeFieldsValid (Time);

+  Status = ConvertRtcTimeToEfiTime (Time, Century, RegisterB);

+  if (!EFI_ERROR (Status)) {

+    Status = RtcTimeFieldsValid (Time);

+  }

   if (EFI_ERROR (Status)) {

     return EFI_DEVICE_ERROR;

   }

@@ -539,16 +539,12 @@ Returns:
     Time->Year    = RtcRead (RTC_ADDRESS_YEAR);

   }

 

-  ConvertRtcTimeToEfiTime (Time, RegisterB);

-

   if (RtcTestCenturyRegister () == EFI_SUCCESS) {

-    Century = BcdToDecimal8 ((UINT8) (RtcRead (RTC_ADDRESS_CENTURY) & 0x7f));

+    Century = (UINT8) (RtcRead (RTC_ADDRESS_CENTURY) & 0x7f);

   } else {

-    Century = BcdToDecimal8 (RtcRead (RTC_ADDRESS_CENTURY));

+    Century = RtcRead (RTC_ADDRESS_CENTURY);

   }

 

-  Time->Year = (UINT16) (Century * 100 + Time->Year);

-

   //

   // Release RTC Lock.

   //

@@ -560,7 +556,10 @@ Returns:
   //

   // Make sure all field values are in correct range

   //

-  Status = RtcTimeFieldsValid (Time);

+  Status = ConvertRtcTimeToEfiTime (Time, Century, RegisterB);

+  if (!EFI_ERROR (Status)) {

+    Status = RtcTimeFieldsValid (Time);

+  }

   if (EFI_ERROR (Status)) {

     return EFI_DEVICE_ERROR;

   }

@@ -719,23 +718,52 @@ Returns:
   return EFI_DEVICE_ERROR;

 }

 

-VOID

-ConvertRtcTimeToEfiTime (

-  IN EFI_TIME       *Time,

-  IN RTC_REGISTER_B RegisterB

+/**

+  Checks an 8-bit BCD value, and converts to an 8-bit value if valid.

+

+  This function checks the 8-bit BCD value specified by Value.

+  If valid, the function converts it to an 8-bit value and returns it.

+  Otherwise, return 0xff.

+

+  @param  Value The 8-bit BCD value to check and convert

+

+  @return The 8-bit value converted.

+          0xff if Value is invalid.

+

+**/

+UINT8

+CheckAndConvertBcd8ToDecimal8 (

+  IN  UINT8  Value

   )

-/*++

+{

+  if ((Value < 0xa0) && ((Value & 0xf) < 0xa)) {

+    return BcdToDecimal8 (Value);

+  }

 

-Routine Description:

+  return 0xff;

+}

 

-  Arguments:

+/**

+  Converts time read from RTC to EFI_TIME format defined by UEFI spec.

 

+  This function converts raw time data read from RTC to the EFI_TIME format

+  defined by UEFI spec.

+  If data mode of RTC is BCD, then converts it to decimal,

+  If RTC is in 12-hour format, then converts it to 24-hour format.

 

+  @param   Time       On input, the time data read from RTC to convert

+                      On output, the time converted to UEFI format

+  @param   Century    Value of century read from RTC.

+  @param   RegisterB  Value of Register B of RTC, indicating data mode

+                      and hour format.

 

-Returns:

---*/

-// GC_TODO:    Time - add argument and description to function comment

-// GC_TODO:    RegisterB - add argument and description to function comment

+**/

+EFI_STATUS

+ConvertRtcTimeToEfiTime (

+  IN OUT EFI_TIME        *Time,

+  IN     UINT8           Century,

+  IN     RTC_REGISTER_B  RegisterB

+  )

 {

   BOOLEAN PM;

 

@@ -748,13 +776,23 @@ Returns:
   Time->Hour = (UINT8) (Time->Hour & 0x7f);

 

   if (RegisterB.Bits.DM == 0) {

-    Time->Year    = BcdToDecimal8 ((UINT8) Time->Year);

-    Time->Month   = BcdToDecimal8 (Time->Month);

-    Time->Day     = BcdToDecimal8 (Time->Day);

-    Time->Hour    = BcdToDecimal8 (Time->Hour);

-    Time->Minute  = BcdToDecimal8 (Time->Minute);

-    Time->Second  = BcdToDecimal8 (Time->Second);

+    Time->Year    = CheckAndConvertBcd8ToDecimal8 ((UINT8) Time->Year);

+    Time->Month   = CheckAndConvertBcd8ToDecimal8 (Time->Month);

+    Time->Day     = CheckAndConvertBcd8ToDecimal8 (Time->Day);

+    Time->Hour    = CheckAndConvertBcd8ToDecimal8 (Time->Hour);

+    Time->Minute  = CheckAndConvertBcd8ToDecimal8 (Time->Minute);

+    Time->Second  = CheckAndConvertBcd8ToDecimal8 (Time->Second);

+    Century       = CheckAndConvertBcd8ToDecimal8 (Century);

+  }

+

+  if (Time->Year == 0xff || Time->Month == 0xff || Time->Day == 0xff ||

+      Time->Hour == 0xff || Time->Minute == 0xff || Time->Second == 0xff ||

+      Century == 0xff) {

+    return EFI_INVALID_PARAMETER;

   }

+

+  Time->Year = (UINT16) (Century * 100 + Time->Year);

+

   //

   // If time is in 12 hour format, convert it to 24 hour format

   //

@@ -771,6 +809,8 @@ Returns:
   Time->Nanosecond  = 0;

   Time->TimeZone    = EFI_UNSPECIFIED_TIMEZONE;

   Time->Daylight    = 0;

+

+  return EFI_SUCCESS;

 }

 

 EFI_STATUS

diff --git a/MdeModulePkg/Universal/PcatRealTimeClockRuntimeDxe/PcRtc.h b/MdeModulePkg/Universal/PcatRealTimeClockRuntimeDxe/PcRtc.h
index c44731a2f8..b0c526ff67 100644
--- a/MdeModulePkg/Universal/PcatRealTimeClockRuntimeDxe/PcRtc.h
+++ b/MdeModulePkg/Universal/PcatRealTimeClockRuntimeDxe/PcRtc.h
@@ -398,27 +398,27 @@ Returns:
 --*/

 ;

 

-VOID

-ConvertRtcTimeToEfiTime (

-  IN EFI_TIME       *Time,

-  IN RTC_REGISTER_B RegisterB

-  )

-/*++

+/**

+  Converts time read from RTC to EFI_TIME format defined by UEFI spec.

 

-Routine Description:

+  This function converts raw time data read from RTC to the EFI_TIME format

+  defined by UEFI spec.

+  If data mode of RTC is BCD, then converts it to decimal,

+  If RTC is in 12-hour format, then converts it to 24-hour format.

 

-  GC_TODO: Add function description

-

-Arguments:

+  @param   Time       On input, the time data read from RTC to convert

+                      On output, the time converted to UEFI format

+  @param   Century    Value of century read from RTC.

+  @param   RegisterB  Value of Register B of RTC, indicating data mode

+                      and hour format.

 

-  Time      - GC_TODO: add argument description

-  RegisterB - GC_TODO: add argument description

-

-Returns:

-

-  GC_TODO: add return values

-

---*/

+**/

+EFI_STATUS

+ConvertRtcTimeToEfiTime (

+  IN OUT EFI_TIME        *Time,

+  IN     UINT8           Century,

+  IN     RTC_REGISTER_B  RegisterB

+  )

 ;

 

 EFI_STATUS