Tolerate memory UEs during dump extraction.

Change-Id: I0dc57ec047beb47b557b816162d619a5b2a54108
RTC: 64619
Reviewed-on: http://gfw160.austin.ibm.com:8080/gerrit/4600
Tested-by: Jenkins Server
Reviewed-by: ADAM R. MUHLE <armuhle@us.ibm.com>
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>
Reviewed-by: A. Patrick Williams III <iawillia@us.ibm.com>

1 files changed, 118 insertions, 0 deletions

diff --git a/src/kernel/machchk.C b/src/kernel/machchk.C
new file mode 100644
index 000000000..746c77c83
--- /dev/null
+++ b/src/kernel/machchk.C
@@ -0,0 +1,118 @@
+/* IBM_PROLOG_BEGIN_TAG                                                   */
+/* This is an automatically generated prolog.                             */
+/*                                                                        */
+/* $Source: src/kernel/machchk.C $                                        */
+/*                                                                        */
+/* IBM CONFIDENTIAL                                                       */
+/*                                                                        */
+/* COPYRIGHT International Business Machines Corp. 2013                   */
+/*                                                                        */
+/* p1                                                                     */
+/*                                                                        */
+/* Object Code Only (OCO) source materials                                */
+/* Licensed Internal Code Source Materials                                */
+/* IBM HostBoot Licensed Internal Code                                    */
+/*                                                                        */
+/* The source code for this program is not published or otherwise         */
+/* divested of its trade secrets, irrespective of what has been           */
+/* deposited with the U.S. Copyright Office.                              */
+/*                                                                        */
+/* Origin: 30                                                             */
+/*                                                                        */
+/* IBM_PROLOG_END_TAG                                                     */
+#include <kernel/machchk.H>
+#include <kernel/console.H>
+#include <kernel/vmmmgr.H>
+#include <sys/mmio.h>
+
+namespace Kernel
+{
+namespace MachineCheck
+{
+
+bool handleLoadUE(task_t* t)
+{
+    bool handled = false;
+
+    static const uint32_t LDX_INSTR_MASK        = 0xFC0007FE;
+    static const uint32_t LDX_INSTR             = 0x7C00002A;
+    static const uint32_t LDX_RA_MASK           = 0x001F0000;
+    static const uint32_t LDX_RB_MASK           = 0x0000F800;
+    static const uint32_t LDX_RT_MASK           = 0x03E00000;
+
+    do
+    {
+        //Get instruction that caused the SUE
+        uint64_t physInstAddr = VmmManager::findKernelAddress(
+                reinterpret_cast<uint64_t>(t->context.nip));
+        uint32_t* instruction = reinterpret_cast<uint32_t*>(physInstAddr);
+
+        if((*instruction & LDX_INSTR_MASK) != LDX_INSTR)
+        {
+            //Not an LDX instruction, unhandled exception
+            printk("MachineCheck::handleUE: Instruction 0x%.8x not handled.\n",
+                   *instruction);
+            break;
+        }
+
+        uint64_t ueMagicValue = 0x0;
+
+        // If task is tolerating UEs, replace with "Dead Data".
+        if (t->tolerate_ue)
+        {
+            ueMagicValue = MM_UE_MAGIC_VALUE;
+        }
+        // Otherwise, check for specific MMIO addresses.
+        else
+        {
+            //Compute the accessed address
+            uint32_t rA = (*instruction & LDX_RA_MASK) >> 16;
+            uint32_t rB = (*instruction & LDX_RB_MASK) >> 11;
+
+            uint64_t vaddr = 0;
+            if(rA != 0)
+            {
+                vaddr = t->context.gprs[rA] +
+                t->context.gprs[rB];
+            }
+            else
+            {
+                vaddr = t->context.gprs[rB];
+            }
+
+            uint64_t phys = VmmManager::findPhysicalAddress(vaddr);
+
+            //Check if address is in IBSCOM MMIO Range.
+            if((phys >= MMIO_IBSCOM_START) &&
+               (phys <= MMIO_IBSCOM_END))
+            {
+                ueMagicValue = MMIO_IBSCOM_UE_DETECTED;
+            }
+            else
+            {
+                printk("MachineCheck::handleUE: Unrecognized address %lx\n",
+                       phys);
+                break;
+            }
+        }
+
+        // Write pattern into result register.
+        uint32_t rT = (*instruction & LDX_RT_MASK) >> 21;
+        t->context.gprs[rT] = ueMagicValue;
+
+        // Advance to next instruction.
+        uint32_t* nextInst = reinterpret_cast<uint32_t*>(t->context.nip);
+        nextInst++;
+        t->context.nip = reinterpret_cast<void*>(nextInst);
+
+        // Successfully handled.
+        handled = true;
+
+    } while (false);
+
+    return handled;
+}
+
+
+}
+}