SCOM Restore: Handle case of old HB and new STOP API case.

Commit addresses a situation where STOP API is new and HB is
old. It detects the siutation and retains legacy behavior.
This situation can arise if PHYP tries to use SCOM restore
changes of STOP API with older fipsdriver or OPAL does the
same on older HB binaries.
Key_Cronus_Test=PM_REGRESS

Change-Id: Iaaa866169904a47e10c79ae4894d2eedccfafe53
Reviewed-on: http://rchgit01.rchland.ibm.com/gerrit1/62610
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: Hostboot CI <hostboot-ci+hostboot@us.ibm.com>
Tested-by: Cronus HW CI <cronushw-ci+hostboot@us.ibm.com>
Reviewed-by: RANGANATHPRASAD G. BRAHMASAMUDRA <prasadbgr@in.ibm.com>
Reviewed-by: AMIT J. TENDOLKAR <amit.tendolkar@in.ibm.com>
Reviewed-by: Gregory S. Still <stillgs@us.ibm.com>
Reviewed-on: http://rchgit01.rchland.ibm.com/gerrit1/62614
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP HW <op-hw-jenkins+hostboot@us.ibm.com>
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Reviewed-by: Christian R. Geddes <crgeddes@us.ibm.com>

src/import/chips/p9/procedures/utils/stopreg/p9_stop_api.C

@@ -32,6 +32,8 @@
 // *HWP Team        :  PM
 // *HWP Level       :  2
 // *HWP Consumed by :  HB:HYP
+
+// *INDENT-OFF*
 #ifdef PPC_HYP
     #include <HvPlicModule.H>
 #endif
@@ -69,6 +71,8 @@ const StopSprReg_t g_sprRegister[] =
 };
 
 const uint32_t MAX_SPR_SUPPORTED =  10;
+const uint32_t LEGACY_CORE_SCOM_SUPPORTED   =   15;
+const uint32_t LEGACY_QUAD_SCOM_SUPPORTED   =   63;
 
 //-----------------------------------------------------------------------------
 
@@ -835,12 +839,24 @@ StopReturnCode_t p9_stop_save_scom( void* const   i_pImage,
             l_maxScomRestoreEntry   =
                 *(uint32_t*)((uint8_t*)i_pImage + CPMR_HOMER_OFFSET + CPMR_MAX_SCOM_REST_PER_CORE_BYTE);
             pScomEntry              =   CORE_ID_SCOM_START(i_pImage, chipletId )
-                                        cacheEntry              =   false;
+            cacheEntry              =   false;
+
+            if( !l_maxScomRestoreEntry )
+            {
+                //Old HB and new STOP API case. Retain legacy Number
+                l_maxScomRestoreEntry   =  SWIZZLE_4_BYTE(LEGACY_CORE_SCOM_SUPPORTED);
+            }
         }
         else
         {
             l_maxScomRestoreEntry   =
                 *(uint32_t*)((uint8_t*)i_pImage + QPMR_HOMER_OFFSET + QPMR_QUAD_MAX_SCOM_ENTRY_BYTE);
+
+            if( !l_maxScomRestoreEntry )
+            {
+                // Incase of a bad HOMER header initialization, fall back on legacy number.
+                l_maxScomRestoreEntry   =  SWIZZLE_4_BYTE(LEGACY_QUAD_SCOM_SUPPORTED);
+            }
             // chiplet is a cache. let us find start address of cache section
             // associated with given chiplet. A cache section associated with
             // given chiplet is split in to L2, L3 and EQ area.
@@ -891,13 +907,16 @@ StopReturnCode_t p9_stop_save_scom( void* const   i_pImage,
                 break;
         }
 
+
         if(( imageVer > LEGACY_SCOM_RESTORE_VER ) && ( cacheEntry ) )
         {
             //STOP API migrated to newer algorithm for creation of entries
+
             pScomEntry  =   CACHE_SCOM_ADDR(i_pImage,
                                             chipletId,
                                             l_maxScomRestoreEntry )
-                            entryLimit  =   l_maxScomRestoreEntry;
+
+            entryLimit  =   l_maxScomRestoreEntry;
         }
 
         if(( !pScomEntry ) || ( l_rc ) )