ARM: Add limited CP14 support.

New kernels attempt to read CP14 what debug architecture is available.
These changes add the debug registers and return that none is currently
available.

2 files changed, 47 insertions, 2 deletions

diff --git a/src/arch/arm/isa/formats/misc.isa b/src/arch/arm/isa/formats/misc.isa
index 54482864a..3865cffe2 100644
--- a/src/arch/arm/isa/formats/misc.isa
+++ b/src/arch/arm/isa/formats/misc.isa
@@ -1,6 +1,6 @@
 // -*- mode:c++ -*-
 
-// Copyright (c) 2010 ARM Limited
+// Copyright (c) 2010-2012 ARM Limited
 // All rights reserved
 //
 // The license below extends only to copyright in the software and shall
@@ -85,6 +85,49 @@ let {{
     '''
     decoder_output = '''
     StaticInstPtr
+    decodeMcrMrc14(ExtMachInst machInst)
+    {
+        const uint32_t opc1 = bits(machInst, 23, 21);
+        const uint32_t crn = bits(machInst, 19, 16);
+        const uint32_t opc2 = bits(machInst, 7, 5);
+        const uint32_t crm = bits(machInst, 3, 0);
+        const MiscRegIndex miscReg = decodeCP14Reg(crn, opc1, crm, opc2);
+        const IntRegIndex rt = (IntRegIndex)(uint32_t)bits(machInst, 15, 12);
+
+        const bool isRead = bits(machInst, 20);
+
+        switch (miscReg) {
+          case MISCREG_NOP:
+            return new NopInst(machInst);
+          case NUM_MISCREGS:
+            return new FailUnimplemented(
+                    csprintf("miscreg crn:%d opc1:%d crm:%d opc2:%d %s unknown",
+                    crn, opc1, crm, opc2, isRead ? "read" : "write").c_str(),
+                    machInst);
+          default:
+            if (isRead) {
+                return new Mrc14(machInst, rt, (IntRegIndex)miscReg);
+            } else {
+                return new Mcr14(machInst, (IntRegIndex)miscReg, rt);
+            }
+        }
+    }
+    '''
+}};
+
+def format McrMrc14() {{
+    decode_block = '''
+    return decodeMcrMrc14(machInst);
+    '''
+}};
+
+let {{
+    header_output = '''
+    StaticInstPtr
+    decodeMcrMrc15(ExtMachInst machInst);
+    '''
+    decoder_output = '''
+    StaticInstPtr
     decodeMcrMrc15(ExtMachInst machInst)
     {
         const uint32_t opc1 = bits(machInst, 23, 21);
diff --git a/src/arch/arm/isa/formats/uncond.isa b/src/arch/arm/isa/formats/uncond.isa
index 0ef113607..4a18a55bb 100644
--- a/src/arch/arm/isa/formats/uncond.isa
+++ b/src/arch/arm/isa/formats/uncond.isa
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 ARM Limited
+// Copyright (c) 2010-2012 ARM Limited
 // All rights reserved
 //
 // The license below extends only to copyright in the software and shall
@@ -269,6 +269,8 @@ def format ArmUnconditional() {{
                 if (bits(op1, 4) == 0) {
                     if (CPNUM == 0xa || CPNUM == 0xb) {
                         return decodeShortFpTransfer(machInst);
+                    } else if (CPNUM == 0xe) {
+                        return decodeMcrMrc14(machInst);
                     } else if (CPNUM == 0xf) {
                         return decodeMcrMrc15(machInst);
                     }