Use new scratch reg for hb_done and set early in IPL

This is to support using the scratch register for the power off
message.  I moved to a new scratch register since we were sharing
with a SBE scratch reg that was needed early in HB IPL.
NOTE! This will have a co-req with an FSP track so we'll need to
coordinate.

CMVC-Coreq: 917527
Change-Id: I5f81f15126d6ad8d2c9459c5afe730554256c037
RTC: 95818
Reviewed-on: http://gfw160.aus.stglabs.ibm.com:8080/gerrit/9220
Tested-by: Jenkins Server
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>
Reviewed-by: MIKE J. JONES <mjjones@us.ibm.com>
Reviewed-by: A. Patrick Williams III <iawillia@us.ibm.com>

6 files changed, 41 insertions, 19 deletions

diff --git a/src/include/kernel/misc.H b/src/include/kernel/misc.H
index a7e40356d..19427c399 100644
--- a/src/include/kernel/misc.H
+++ b/src/include/kernel/misc.H
@@ -50,6 +50,21 @@ namespace KernelMisc
     /** @brief master host boot instance number (node) */
     extern uint64_t g_masterHBInstance;
 
+    /** @brief Indicate whether HB is running or not */
+    enum HbRunning
+    {
+        HB_RUNNING = 0,
+        HB_SHUTDOWN = 1,
+    };
+
+    /** @fn setHbScratchStatus
+     *  @brief Set scratch register indicating HB running status
+     *
+     *  @param i_status Indicates whether to say HB is running or shutdown
+     *  @return void
+     */
+    void setHbScratchStatus(enum HbRunning i_status);
+
     /** @fn in_kernel_mode
      *  @brief Determine if the code is currently in kernel mode or not.
      *
diff --git a/src/include/sys/mmio.h b/src/include/sys/mmio.h
index d536b281b..29f560bd6 100644
--- a/src/include/sys/mmio.h
+++ b/src/include/sys/mmio.h
@@ -5,7 +5,7 @@
 /*                                                                        */
 /* IBM CONFIDENTIAL                                                       */
 /*                                                                        */
-/* COPYRIGHT International Business Machines Corp. 2010,2013              */
+/* COPYRIGHT International Business Machines Corp. 2010,2014              */
 /*                                                                        */
 /* p1                                                                     */
 /*                                                                        */
@@ -86,8 +86,9 @@ enum MMIO_Scratch_Register
     MMIO_SCRATCH_PNOR_MODE = 0x8,
         /** Thread2 Scratch Register - Unused */
     MMIO_SCRATCH_ISTEP_MODE = 0x10,
-        /** Thread3 Scratch Register - Unused */
-    MMIO_SCRATCH_RSVD_T3 = 0x18,
+        /** Thread3 Scratch Register - Identifies if Hostboot is active after
+         *                             host_start_payload. */
+    MMIO_SCRATCH_HOSTBOOT_ACTIVE = 0x18,
         /** Thread4 Scratch Register - Unused */
     MMIO_SCRATCH_RSVD_T4 = 0x20,
         /** Thread5 Scratch Register - Unused (unit tests may modify) */
@@ -95,9 +96,6 @@ enum MMIO_Scratch_Register
         /** Thread6 Scratch Register - Identifies where hostboot currently
                                        resides and how large the space is */
     MMIO_SCRATCH_MEMORY_STATE = 0x30,
-        /** Thread7 Scratch Register - Identifies if Hostboot is active after
-         *                             host_start_payload. */
-    MMIO_SCRATCH_HOSTBOOT_ACTIVE = 0x38,
         /** Thread7 Scratch Register - Set be SBE for reduced-threads support
          *                             for AVPs.  */
     MMIO_SCRATCH_AVP_THREADS = 0x38,
diff --git a/src/kernel/kernel.C b/src/kernel/kernel.C
index 1f5770280..291e95553 100644
--- a/src/kernel/kernel.C
+++ b/src/kernel/kernel.C
@@ -34,6 +34,7 @@
 #include <kernel/timemgr.H>
 #include <sys/vfs.h>
 #include <kernel/deferred.H>
+#include <kernel/misc.H>
 
 #include <stdlib.h>
 
@@ -66,6 +67,9 @@ int main()
     kernel.memBootstrap();
     kernel.cpuBootstrap();
 
+    // Let FSP/BMC know that Hostboot is now running
+    KernelMisc::setHbScratchStatus(KernelMisc::HB_RUNNING);
+
     kernel.inittaskBootstrap();
 
     // Ready to let the other CPUs go.
diff --git a/src/kernel/misc.C b/src/kernel/misc.C
index cba6a152c..4588518d2 100644
--- a/src/kernel/misc.C
+++ b/src/kernel/misc.C
@@ -220,12 +220,26 @@ namespace KernelMisc
             // First indicate to the FSP that we're done by clearing out the
             // "hostboot_done" register.  We need to do this since this is the
             // power off path.
-            updateScratchReg(MMIO_SCRATCH_HOSTBOOT_ACTIVE,0);
+            setHbScratchStatus(HB_SHUTDOWN);
 
             terminateExecuteTI();
         }
     }
 
+    void setHbScratchStatus(enum HbRunning i_status)
+    {
+        if(i_status == HB_RUNNING)
+        {
+            const char * hostboot_string = "hostboot";
+            updateScratchReg(MMIO_SCRATCH_HOSTBOOT_ACTIVE,
+                        *reinterpret_cast<const uint64_t*>(hostboot_string));
+        }
+        else
+        {
+            updateScratchReg(MMIO_SCRATCH_HOSTBOOT_ACTIVE,0);
+        }
+    }
+
     void WinkleCore::masterPreWork()
     {
         printk("Winkle threads - ");
@@ -290,9 +304,7 @@ namespace KernelMisc
                          kernel_hbDescriptor.kernelMemoryState);
 
         // Set scratch register to indicate Hostboot is [still] active.
-        const char * hostboot_string = "hostboot";
-        updateScratchReg(MMIO_SCRATCH_HOSTBOOT_ACTIVE,
-                         *reinterpret_cast<const uint64_t*>(hostboot_string));
+        setHbScratchStatus(HB_RUNNING);
 
         // Restore caller of cpu_master_winkle().
         iv_caller->state = TASK_STATE_RUNNING;
@@ -393,9 +405,7 @@ namespace KernelMisc
                          kernel_hbDescriptor.kernelMemoryState);
 
         // Set scratch register to indicate Hostboot is [still] active.
-        const char * hostboot_string = "hostboot";
-        updateScratchReg(MMIO_SCRATCH_HOSTBOOT_ACTIVE,
-                         *reinterpret_cast<const uint64_t*>(hostboot_string));
+        setHbScratchStatus(HB_RUNNING);
 
         // Restore caller of cpu_all_winkle().
         iv_caller->state = TASK_STATE_RUNNING;
diff --git a/src/kernel/shutdown.S b/src/kernel/shutdown.S
index bee5f0086..119a89868 100644
--- a/src/kernel/shutdown.S
+++ b/src/kernel/shutdown.S
@@ -142,7 +142,7 @@ kernel_shutdown_ea0_1_mode:
     isync
 2:
     ;// Clear "Hostboot active" scratch register.
-    li r3, (0x40 + 0x38) ;// See sys/mmio.h
+    li r3, (0x40 + 0x18) ;// See sys/mmio.h
     mtspr SPRC, r3
     li r3, 0x0
     mtspr SPRD, r3
diff --git a/src/usr/hwpf/hwp/start_payload/start_payload.C b/src/usr/hwpf/hwp/start_payload/start_payload.C
index 5ee237b88..fcbef580f 100644
--- a/src/usr/hwpf/hwp/start_payload/start_payload.C
+++ b/src/usr/hwpf/hwp/start_payload/start_payload.C
@@ -506,11 +506,6 @@ errlHndl_t callShutdown ( uint64_t i_masterInstance,
             break;
         }
 
-        // Set scratch register to indicate Hostboot is [still] active.
-        const char * hostboot_string = "hostboot";
-        mmio_scratch_write(MMIO_SCRATCH_HOSTBOOT_ACTIVE,
-                           *reinterpret_cast<const uint64_t*>(hostboot_string));
-
         // Get Target Service, and the system target.
         TargetService& tS = targetService();
         TARGETING::Target* sys = NULL;