arm: Add support for the dc {civac, cvac, cvau, ivac} instr

This patch adds support for decoding and executing the following ARMv8
cache maintenance instructions by Virtual Address:
* dc civac: Clean and Invalidate by Virtual Address to the Point
            of Coherency
* dc cvac: Clean by Virtual Address to the Point of Coherency
* dc cvau: Clean by Virtual Address to the Point of Unification
* dc ivac: Invalidate by Virtual Addrsess to the Point of Coherency

Change-Id: I58cabda37f9636105fda1b1e84a0a04965fb5670
Reviewed-by: Sudhanshu Jha <sudhanshu.jha@arm.com>
Reviewed-by: Stephan Diestelhorst <stephan.diestelhorst@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5060
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
diff --git a/src/arch/arm/insts/mem64.hh b/src/arch/arm/insts/mem64.hh
index 933d345..7ad2f52 100644
--- a/src/arch/arm/insts/mem64.hh
+++ b/src/arch/arm/insts/mem64.hh
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011-2013 ARM Limited
+ * Copyright (c) 2011-2013,2017 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
@@ -52,9 +52,9 @@
     uint64_t imm;
 
     SysDC64(const char *mnem, ExtMachInst _machInst, OpClass __opClass,
-            IntRegIndex _base, IntRegIndex _dest, uint64_t _imm)
-        : ArmStaticInst(mnem, _machInst, __opClass), base(_base), dest(_dest),
-        imm(_imm)
+            IntRegIndex _base, MiscRegIndex miscReg, uint64_t _imm)
+        : ArmStaticInst(mnem, _machInst, __opClass), base(_base),
+          dest((IntRegIndex)miscReg), imm(_imm)
     {}
     std::string generateDisassembly(Addr pc, const SymbolTable *symtab) const;
 };
diff --git a/src/arch/arm/isa/formats/aarch64.isa b/src/arch/arm/isa/formats/aarch64.isa
index d640caf..0179f2f 100644
--- a/src/arch/arm/isa/formats/aarch64.isa
+++ b/src/arch/arm/isa/formats/aarch64.isa
@@ -350,6 +350,7 @@
                     if (read) {
                         if ((miscReg == MISCREG_DC_CIVAC_Xt) ||
                             (miscReg == MISCREG_DC_CVAC_Xt) ||
+                            (miscReg == MISCREG_DC_IVAC_Xt)  ||
                             (miscReg == MISCREG_DC_ZVA_Xt)) {
                             return new Unknown64(machInst);
                         }
@@ -365,16 +366,26 @@
                                 return new MsrNZCV64(machInst, (IntRegIndex) miscReg, rt);
                         }
                         uint32_t iss = msrMrs64IssBuild(read, op0, op1, crn, crm, op2, rt);
-                        if (miscReg == MISCREG_DC_ZVA_Xt && !read)
-                            return new Dczva(machInst, rt, (IntRegIndex) miscReg, iss);
-
                         if (read) {
                             StaticInstPtr si = new Mrs64(machInst, rt, miscReg, iss);
                             if (miscRegInfo[miscReg][MISCREG_UNVERIFIABLE])
                                 si->setFlag(StaticInst::IsUnverifiable);
                             return si;
                         } else {
-                            return new Msr64(machInst, miscReg, rt, iss);
+                            switch (miscReg) {
+                              case MISCREG_DC_ZVA_Xt:
+                                return new Dczva(machInst, rt, miscReg, iss);
+                              case MISCREG_DC_CVAU_Xt:
+                                return new Dccvau(machInst, rt, miscReg, iss);
+                              case MISCREG_DC_CVAC_Xt:
+                                return new Dccvac(machInst, rt, miscReg, iss);
+                              case MISCREG_DC_CIVAC_Xt:
+                                return new Dccivac(machInst, rt, miscReg, iss);
+                              case MISCREG_DC_IVAC_Xt:
+                                return new Dcivac(machInst, rt, miscReg, iss);
+                              default:
+                                return new Msr64(machInst, miscReg, rt, iss);
+                            }
                         }
                     } else if (miscRegInfo[miscReg][MISCREG_WARN_NOT_FAIL]) {
                         std::string full_mnem = csprintf("%s %s",
diff --git a/src/arch/arm/isa/insts/data64.isa b/src/arch/arm/isa/insts/data64.isa
index 887130f..41e36d3 100644
--- a/src/arch/arm/isa/insts/data64.isa
+++ b/src/arch/arm/isa/insts/data64.isa
@@ -1,6 +1,6 @@
 // -*- mode:c++ -*-
 
-// Copyright (c) 2011-2013, 2016 ARM Limited
+// Copyright (c) 2011-2013, 2016-2017 ARM Limited
 // All rights reserved
 //
 // The license below extends only to copyright in the software and shall
@@ -317,7 +317,8 @@
             if (flat_idx == MISCREG_DAIF ||
                 flat_idx == MISCREG_DC_ZVA_Xt ||
                 flat_idx == MISCREG_DC_CVAC_Xt ||
-                flat_idx == MISCREG_DC_CIVAC_Xt
+                flat_idx == MISCREG_DC_CIVAC_Xt ||
+                flat_idx == MISCREG_DC_IVAC_Xt
                 )
                 return std::make_shared<UndefinedInstruction>(
                                     machInst, 0, EC_TRAPPED_MSR_MRS_64,
@@ -427,6 +428,117 @@
     exec_output += Store64CompleteAcc.subst(msrDCZVAIop);
 
 
+    msrdccvau_ea_code = '''
+        MiscRegIndex flat_idx = (MiscRegIndex) xc->tcBase()->flattenRegId(
+                                   RegId(MiscRegClass, dest)).index();
+        CPSR cpsr = Cpsr;
+        ExceptionLevel el = (ExceptionLevel) (uint8_t) cpsr.el;
+    '''
+
+    msrdccvau_ea_code += msrMrs64EnabledCheckCode % ('Write', 'false')
+    msrdccvau_ea_code += '''
+           Request::Flags memAccessFlags = Request::CLEAN | Request::DST_POU |
+              ArmISA::TLB::MustBeOne;
+           EA = XBase;
+           System *sys = xc->tcBase()->getSystemPtr();
+           Addr op_size = sys->cacheLineSize();
+           EA &= ~(op_size - 1);
+    '''
+
+    msrDCCVAUIop = InstObjParams("dc cvau", "Dccvau", "SysDC64",
+                { "ea_code" : msrdccvau_ea_code,
+                  "memacc_code" : ";", "use_uops" : 0,
+                  "op_wb" : ";", "fa_code" : ";"}, ['IsStore', 'IsMemRef']);
+    header_output += DCStore64Declare.subst(msrDCCVAUIop);
+    decoder_output += DCStore64Constructor.subst(msrDCCVAUIop);
+    exec_output += DCStore64Execute.subst(msrDCCVAUIop);
+    exec_output += DCStore64InitiateAcc.subst(msrDCCVAUIop);
+    exec_output += Store64CompleteAcc.subst(msrDCCVAUIop);
+
+
+    msrdccvac_ea_code = '''
+        MiscRegIndex flat_idx = (MiscRegIndex) xc->tcBase()->flattenRegId(
+            RegId(MiscRegClass, dest)).index();
+        CPSR cpsr = Cpsr;
+        ExceptionLevel el = (ExceptionLevel) (uint8_t) cpsr.el;
+    '''
+
+    msrdccvac_ea_code += msrMrs64EnabledCheckCode % ('Write', 'false')
+    msrdccvac_ea_code += '''
+           Request::Flags memAccessFlags = Request::CLEAN | Request::DST_POC |
+              ArmISA::TLB::MustBeOne;
+           EA = XBase;
+           System *sys = xc->tcBase()->getSystemPtr();
+           Addr op_size = sys->cacheLineSize();
+           EA &= ~(op_size - 1);
+    '''
+
+    msrDCCVACIop = InstObjParams("dc cvac", "Dccvac", "SysDC64",
+                { "ea_code" : msrdccvac_ea_code,
+                  "memacc_code" : ";", "use_uops" : 0,
+                  "op_wb" : ";", "fa_code" : ";"}, ['IsStore', 'IsMemRef']);
+    header_output += DCStore64Declare.subst(msrDCCVACIop);
+    decoder_output += DCStore64Constructor.subst(msrDCCVACIop);
+    exec_output += DCStore64Execute.subst(msrDCCVACIop);
+    exec_output += DCStore64InitiateAcc.subst(msrDCCVACIop);
+    exec_output += Store64CompleteAcc.subst(msrDCCVACIop);
+
+
+    msrdccivac_ea_code = '''
+        MiscRegIndex flat_idx = (MiscRegIndex) xc->tcBase()->flattenRegId(
+                                   RegId(MiscRegClass, dest)).index();
+        CPSR cpsr = Cpsr;
+        ExceptionLevel el = (ExceptionLevel) (uint8_t) cpsr.el;
+    '''
+
+    msrdccivac_ea_code += msrMrs64EnabledCheckCode % ('Write', 'false')
+    msrdccivac_ea_code += '''
+           Request::Flags memAccessFlags = Request::CLEAN |
+              Request::INVALIDATE | Request::DST_POC | ArmISA::TLB::MustBeOne;
+           EA = XBase;
+           System *sys = xc->tcBase()->getSystemPtr();
+           Addr op_size = sys->cacheLineSize();
+           EA &= ~(op_size - 1);
+    '''
+
+    msrDCCIVACIop = InstObjParams("dc civac", "Dccivac", "SysDC64",
+                { "ea_code" : msrdccivac_ea_code,
+                  "memacc_code" : ";", "use_uops" : 0,
+                  "op_wb" : ";", "fa_code" : ";"}, ['IsStore', 'IsMemRef']);
+    header_output += DCStore64Declare.subst(msrDCCIVACIop);
+    decoder_output += DCStore64Constructor.subst(msrDCCIVACIop);
+    exec_output += DCStore64Execute.subst(msrDCCIVACIop);
+    exec_output += DCStore64InitiateAcc.subst(msrDCCIVACIop);
+    exec_output += Store64CompleteAcc.subst(msrDCCIVACIop);
+
+
+    msrdcivac_ea_code = '''
+        MiscRegIndex flat_idx = (MiscRegIndex) xc->tcBase()->flattenRegId(
+                                   RegId(MiscRegClass, dest)).index();
+        CPSR cpsr = Cpsr;
+        ExceptionLevel el = (ExceptionLevel) (uint8_t) cpsr.el;
+    '''
+
+    msrdcivac_ea_code += msrMrs64EnabledCheckCode % ('Write', 'false')
+    msrdcivac_ea_code += '''
+           Request::Flags memAccessFlags = Request::INVALIDATE |
+              Request::DST_POC | ArmISA::TLB::MustBeOne;
+           EA = XBase;
+           System *sys = xc->tcBase()->getSystemPtr();
+           Addr op_size = sys->cacheLineSize();
+           EA &= ~(op_size - 1);
+    '''
+
+    msrDCIVACIop = InstObjParams("dc ivac", "Dcivac", "SysDC64",
+                { "ea_code" : msrdcivac_ea_code,
+                  "memacc_code" : ";", "use_uops" : 0,
+                  "op_wb" : ";", "fa_code" : ";"}, ['IsStore', 'IsMemRef']);
+    header_output += DCStore64Declare.subst(msrDCIVACIop);
+    decoder_output += DCStore64Constructor.subst(msrDCIVACIop);
+    exec_output += DCStore64Execute.subst(msrDCIVACIop);
+    exec_output += DCStore64InitiateAcc.subst(msrDCIVACIop);
+    exec_output += Store64CompleteAcc.subst(msrDCIVACIop);
+
 
     buildDataXImmInst("msrSP", '''
         if (!canWriteAArch64SysReg(
diff --git a/src/arch/arm/isa/templates/mem64.isa b/src/arch/arm/isa/templates/mem64.isa
index ff41148..a44a3cd 100644
--- a/src/arch/arm/isa/templates/mem64.isa
+++ b/src/arch/arm/isa/templates/mem64.isa
@@ -1,6 +1,6 @@
 // -*- mode:c++ -*-
 
-// Copyright (c) 2011-2014 ARM Limited
+// Copyright (c) 2011-2014, 2017 ARM Limited
 // All rights reserved
 //
 // The license below extends only to copyright in the software and shall
@@ -256,7 +256,8 @@
       public:
 
         /// Constructor.
-        %(class_name)s(ExtMachInst machInst, IntRegIndex _base, IntRegIndex _dest, uint64_t _imm);
+        %(class_name)s(ExtMachInst machInst, IntRegIndex _base,
+                       MiscRegIndex _dest, uint64_t _imm);
 
         Fault execute(ExecContext *, Trace::InstRecord *) const;
         Fault initiateAcc(ExecContext *, Trace::InstRecord *) const;
@@ -270,9 +271,10 @@
 }};
 
 def template DCStore64Constructor {{
-    %(class_name)s::%(class_name)s(ExtMachInst machInst, IntRegIndex _base, IntRegIndex _dest, uint64_t _imm)
+    %(class_name)s::%(class_name)s(ExtMachInst machInst, IntRegIndex _base,
+                                   MiscRegIndex _dest, uint64_t _imm)
          : %(base_class)s("%(mnemonic)s", machInst, %(op_class)s,
-                 (IntRegIndex)_base, _dest, _imm)
+                          _base, _dest, _imm)
     {
         %(constructor)s;
         assert(!%(use_uops)d);