Restore Timebase on Master Core Threads 1-3 after Sleep/Winkle

Change-Id: I329dd64345f2474cb0dad628ccc2244d85be86c2
CQ: SW429364
Reviewed-on: http://rchgit01.rchland.ibm.com/gerrit1/63147
Reviewed-by: ILYA SMIRNOV <ismirno@us.ibm.com>
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Reviewed-by: Prachi Gupta <pragupta@us.ibm.com>
Reviewed-by: Christian R. Geddes <crgeddes@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: Daniel M. Crowell <dcrowell@us.ibm.com>

src/include/kernel/cpu.H

@@ -104,6 +104,9 @@ struct cpu_t
     /** Sequence ID of CPU initialization. */
     uint64_t cpu_start_seqid;
 
+    /** Timebase Restore Value (used during core wakeup) */
+    uint64_t cpu_restore_tb;
+
     /** Stack of WorkItems to be executed during doorbell wakeup */
     Util::Lockfree::Stack<KernelWorkItem> doorbell_actions;
 };

src/include/kernel/doorbell.H

@@ -56,6 +56,13 @@ void send_doorbell_wakeup(uint64_t i_pir);
  */
 void send_doorbell_ipc(uint64_t i_pir);
 
+/** Send a doorbell and also restore the thread's timebase
+ *
+ * @param i_pir - PIR to send doorbell to wakeup
+ * @param i_tb  - Timebase value to restore during wakeup
+ */
+void send_doorbell_restore_tb(uint64_t i_pir, uint64_t i_tb);
+
 enum
 {
     _DOORBELL_MSG_TYPE = 0x0000000028000000, /// Comes from the ISA.

src/include/kernel/workitem.H

@@ -53,6 +53,18 @@ class CpuWakeupDoorbellWorkItem : public KernelWorkItem
         ~CpuWakeupDoorbellWorkItem() = default;
 };
 
+//A work item to be created/executed during a Master CPU
+// wakeup scenario, it will also restore the timebase
+// on the threads being woken up
+class CpuTbRestoreDoorbellWorkItem : public KernelWorkItem
+{
+    public:
+        //Implement operator() function
+        void operator() (void);
+
+        //No data to clean up, use default destructor
+        ~CpuTbRestoreDoorbellWorkItem() = default;
+};
 
 #endif
 

src/kernel/cpumgr.C

@@ -253,6 +253,7 @@ void CpuManager::startCPU(ssize_t i)
         cpu->idle_task = TaskManager::createIdleTask();
         cpu->idle_task->cpu = cpu;
         cpu->periodic_count = 0;
+        cpu->cpu_restore_tb = 0;
 
         // Call TimeManager setup for a CPU.
         TimeManager::init_cpu(cpu);

src/kernel/doorbell.C

@@ -79,6 +79,20 @@ void send_doorbell_wakeup(uint64_t i_pir)
     doorbell_send(i_pir);
 }
 
+void send_doorbell_restore_tb(uint64_t i_pir, uint64_t i_tb)
+{
+    cpu_t *l_cpu = CpuManager::getCpu(i_pir);
+    l_cpu->cpu_restore_tb = i_tb;
+
+    printkd("send_doorbell_restore_tb to pir: %lx\n", i_pir);
+    //Create WorkItem and put on the stack to be executed during doorbell
+    // execution
+    KernelWorkItem* l_work = new CpuTbRestoreDoorbellWorkItem();
+    l_cpu->doorbell_actions.push(l_work);
+    //Send doorbell to wakeup core/thread
+    doorbell_send(i_pir);
+}
+
 void send_doorbell_ipc(uint64_t i_pir)
 {
     printk("send_doorbell_ipc to pir: %lx\n", i_pir);

src/kernel/misc.C

@@ -348,7 +348,7 @@ namespace KernelMisc
                 // NOTE: The deferred work container verifies master core
                 // threads 1-3 wake up so a direct doorbell can be sent. For
                 // threads on other cores send_doorbell_wakeup() is used.
-                doorbell_send(l_pir + i);
+                send_doorbell_restore_tb(l_pir + i, iv_timebase);
             }
         }
 
@@ -358,7 +358,6 @@ namespace KernelMisc
         {
             cpu->scheduler->setNextRunnable();
         }
-
     }
 
     void WinkleCore::masterPostWork()
@@ -465,7 +464,6 @@ namespace KernelMisc
         {
             cpu->scheduler->setNextRunnable();
         }
-
     }
 
     void WinkleAll::masterPostWork()

src/kernel/workitem.C

@@ -27,6 +27,7 @@
 #include <kernel/workitem.H>
 #include <kernel/console.H>
 #include <kernel/intmsghandler.H>
+#include <kernel/cpumgr.H>
 
 //Define the desired behavior for a CPU core/thread
 // wakeup scenario
@@ -40,3 +41,17 @@ void CpuWakeupDoorbellWorkItem::operator() (void)
     InterruptMsgHdlr::sendThreadWakeupMsg(pir);
     return;
 }
+
+void CpuTbRestoreDoorbellWorkItem::operator() (void)
+{
+    size_t pir = getPIR();
+    cpu_t *l_cpu = CpuManager::getCpu(pir);
+
+    uint64_t l_restore_tb = l_cpu->cpu_restore_tb;
+    printkd("pir:%ld tb:0x%0x\n", pir, l_restore_tb);
+    if (l_restore_tb > getTB())
+    {
+        setTB(l_restore_tb);
+    }
+    return;
+}