[Linaro-uefi,linaro-uefi,v5,44/44] D03: enhance RTC lock acquiring

diff --git a/Platforms/Hisilicon/D03/Include/Library/CpldD03.h b/Platforms/Hisilicon/D03/Include/Library/CpldD03.h
index 78aec2f..456bf4b 100644
--- a/Platforms/Hisilicon/D03/Include/Library/CpldD03.h
+++ b/Platforms/Hisilicon/D03/Include/Library/CpldD03.h
@@ -17,5 +17,9 @@ 
 #define __CPLD_D03_H__
 
 #define CPLD_BIOSINDICATE_FLAG  0x09
+#define CPLD_I2C_SWITCH_FLAG    0x17
+#define CPU_GET_I2C_CONTROL     BIT2
+#define BMC_I2C_STATUS          BIT3
+
 
 #endif
diff --git a/Platforms/Hisilicon/D03/Library/DS3231RealTimeClockLib/DS3231RealTimeClockLib.c b/Platforms/Hisilicon/D03/Library/DS3231RealTimeClockLib/DS3231RealTimeClockLib.c
index fa63027..3d4a624 100644
--- a/Platforms/Hisilicon/D03/Library/DS3231RealTimeClockLib/DS3231RealTimeClockLib.c
+++ b/Platforms/Hisilicon/D03/Library/DS3231RealTimeClockLib/DS3231RealTimeClockLib.c
@@ -38,6 +38,7 @@ 
 #include <Protocol/RealTimeClock.h>
 #include <Library/I2CLib.h>
 #include "DS3231RealTimeClock.h"
+#include <Library/CpldD03.h>
 #include <Library/CpldIoLib.h>
 
 extern I2C_DEVICE gDS3231RtcDevice;
@@ -56,6 +57,48 @@  IdentifyDS3231 (
 }
 
 EFI_STATUS
+SwitchRtcI2cChannelAndLock(VOID)
+{
+  UINT8   Temp;
+  UINT8   Count;
+
+  for (Count = 0; Count < 20; Count++){
+    Temp = ReadCpldReg(CPLD_I2C_SWITCH_FLAG);
+
+    if ((Temp & BMC_I2C_STATUS) != 0){
+      //The I2C channel is shared with BMC,
+      //and we need some time to get the idle status,
+      //we only switch I2C channel to RTC when it is not busy
+      MicroSecondDelay(30000);
+
+      continue;
+    }
+
+    Temp = ReadCpldReg(CPLD_I2C_SWITCH_FLAG);
+    Temp = Temp | CPU_GET_I2C_CONTROL;
+    WriteCpldReg(CPLD_I2C_SWITCH_FLAG, Temp);
+    //This is empirical value,give cpld some time to make sure the
+    //value is wrote in
+    MicroSecondDelay(2);
+    Temp = ReadCpldReg(CPLD_I2C_SWITCH_FLAG);
+
+    if ((Temp & CPU_GET_I2C_CONTROL) == CPU_GET_I2C_CONTROL){
+      return EFI_SUCCESS;
+    }
+    //There need 30ms to keep consistent with the previous loops if the CPU failed
+    //to get control of I2C
+    MicroSecondDelay(30000);
+  }
+
+  Temp = ReadCpldReg(CPLD_I2C_SWITCH_FLAG);
+  Temp = Temp & ~CPU_GET_I2C_CONTROL;
+  WriteCpldReg(CPLD_I2C_SWITCH_FLAG, Temp);
+
+  return EFI_NOT_READY;
+}
+
+
+EFI_STATUS
 InitializeDS3231 (
   VOID
   )
@@ -136,19 +179,17 @@  LibGetTime (
     return EFI_INVALID_PARAMETER;
   }
 
-
-
-  Temp = ReadCpldReg(0x17);
-  while( (Temp & BIT3) != 0)
-  {
-      Temp = ReadCpldReg(0x17);
+  Status = SwitchRtcI2cChannelAndLock();
+  if(EFI_ERROR (Status)) {
+    return Status;
   }
-  WriteCpldReg(0x17,0x4);
+
   // Initialize the hardware if not already done
   if (!mDS3231Initialized) {
     Status = InitializeDS3231 ();
     if (EFI_ERROR (Status)) {
-      return EFI_NOT_READY;
+      Status = EFI_NOT_READY;
+      goto GExit;
     }
   }
 
@@ -175,7 +216,8 @@  LibGetTime (
 
   BaseHour = 0;
   if((Temp&0x30) == 0x30){
-    return EFI_DEVICE_ERROR;
+    Status = EFI_DEVICE_ERROR;
+    goto GExit;
   }else if(Temp&0x20){
     BaseHour = 20;
   }else if(Temp&0x10){
@@ -196,11 +238,15 @@  LibGetTime (
   Time->TimeZone    = EFI_UNSPECIFIED_TIMEZONE;
 
   if((EFI_ERROR(Status)) || (!IsTimeValid(Time)) || ((Time->Year - BaseYear) > 99)) {
-    return EFI_DEVICE_ERROR;
+    Status = EFI_UNSUPPORTED;
   }
 
-  WriteCpldReg(0x17,0x0);
-  return EFI_SUCCESS;
+GExit:
+  Temp = ReadCpldReg(CPLD_I2C_SWITCH_FLAG);
+  Temp = Temp & ~CPU_GET_I2C_CONTROL;
+  WriteCpldReg(CPLD_I2C_SWITCH_FLAG, Temp);
+
+  return Status;
 
 }
 
@@ -234,13 +280,10 @@  LibSetTime (
     return EFI_INVALID_PARAMETER;
   }
 
-
-  Temp = ReadCpldReg(0x17);
-  while( (Temp & BIT3) != 0)
-  {
-      Temp = ReadCpldReg(0x17);
+  Status = SwitchRtcI2cChannelAndLock();
+  if(EFI_ERROR (Status)) {
+    return Status;
   }
-  WriteCpldReg(0x17,0x4);
 
   // Initialize the hardware if not already done
   if (!mDS3231Initialized) {
@@ -313,7 +356,9 @@  LibSetTime (
 
   EXIT:
 
-  WriteCpldReg(0x17,0x0);
+  Temp = ReadCpldReg(CPLD_I2C_SWITCH_FLAG);
+  Temp = Temp & ~CPU_GET_I2C_CONTROL;
+  WriteCpldReg(CPLD_I2C_SWITCH_FLAG, Temp);
 
   return Status;
 }
diff --git a/Platforms/Hisilicon/D03/Library/DS3231RealTimeClockLib/DS3231RealTimeClockLib.inf b/Platforms/Hisilicon/D03/Library/DS3231RealTimeClockLib/DS3231RealTimeClockLib.inf
index 8121f37..ae1b9b8 100644
--- a/Platforms/Hisilicon/D03/Library/DS3231RealTimeClockLib/DS3231RealTimeClockLib.inf
+++ b/Platforms/Hisilicon/D03/Library/DS3231RealTimeClockLib/DS3231RealTimeClockLib.inf
@@ -30,6 +30,7 @@ 
   MdePkg/MdePkg.dec
   EmbeddedPkg/EmbeddedPkg.dec
   OpenPlatformPkg/OpenPlatformPkg.dec
+  OpenPlatformPkg/Platforms/Hisilicon/D03/D03.dec
   OpenPlatformPkg/Chips/Hisilicon/HisiPkg.dec
 
 [LibraryClasses]
@@ -41,6 +42,7 @@ 
   TimerLib
 # Use EFiAtRuntime to check stage
   UefiRuntimeLib
+  CpldIoLib
   EfiTimeBaseLib
 
 [Pcd]