arch-arm: Init AArch64 ID registers in SE mode

One of the auxv vector's flag is the HWCAP, whose bits match the content
of several arm ID registers.  This patch factors out AArch64 ID
registers init into a separate method and creates the symmetric AArch32
ID register init as well, so that we get a meaningful auxiliary vector
in SE mode.

Change-Id: I52bdb31b67508c4447558ebd7ca743733a69280e
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/13064
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

2 files changed, 42 insertions, 21 deletions

diff --git a/src/arch/arm/isa.cc b/src/arch/arm/isa.cc
index 9a4fb2805..6063607f0 100644
--- a/src/arch/arm/isa.cc
+++ b/src/arch/arm/isa.cc
@@ -84,12 +84,12 @@ ISA::ISA(Params *p)
         haveLPAE = system->haveLPAE();
         haveVirtualization = system->haveVirtualization();
         haveLargeAsid64 = system->haveLargeAsid64();
-        physAddrRange64 = system->physAddrRange64();
+        physAddrRange = system->physAddrRange();
     } else {
         highestELIs64 = true; // ArmSystem::highestELIs64 does the same
         haveSecurity = haveLPAE = haveVirtualization = false;
         haveLargeAsid64 = false;
-        physAddrRange64 = 32;  // dummy value
+        physAddrRange = 32;  // dummy value
     }
 
     initializeMiscRegMetadata();
@@ -114,22 +114,13 @@ ISA::clear()
     SCTLR sctlr_rst = miscRegs[MISCREG_SCTLR_RST];
     memset(miscRegs, 0, sizeof(miscRegs));
 
-    // Initialize configurable default values
-    miscRegs[MISCREG_MIDR] = p->midr;
-    miscRegs[MISCREG_MIDR_EL1] = p->midr;
-    miscRegs[MISCREG_VPIDR] = p->midr;
+    initID32(p);
 
-    miscRegs[MISCREG_ID_ISAR0] = p->id_isar0;
-    miscRegs[MISCREG_ID_ISAR1] = p->id_isar1;
-    miscRegs[MISCREG_ID_ISAR2] = p->id_isar2;
-    miscRegs[MISCREG_ID_ISAR3] = p->id_isar3;
-    miscRegs[MISCREG_ID_ISAR4] = p->id_isar4;
-    miscRegs[MISCREG_ID_ISAR5] = p->id_isar5;
-
-    miscRegs[MISCREG_ID_MMFR0] = p->id_mmfr0;
-    miscRegs[MISCREG_ID_MMFR1] = p->id_mmfr1;
-    miscRegs[MISCREG_ID_MMFR2] = p->id_mmfr2;
-    miscRegs[MISCREG_ID_MMFR3] = p->id_mmfr3;
+    // We always initialize AArch64 ID registers even
+    // if we are in AArch32. This is done since if we
+    // are in SE mode we don't know if our ArmProcess is
+    // AArch32 or AArch64
+    initID64(p);
 
     if (FullSystem && system->highestELIs64()) {
         // Initialize AArch64 state
@@ -290,7 +281,32 @@ ISA::clear64(const ArmISAParams *p)
         // Always non-secure
         miscRegs[MISCREG_SCR_EL3] = 1;
     }
+}
+
+void
+ISA::initID32(const ArmISAParams *p)
+{
+    // Initialize configurable default values
+    miscRegs[MISCREG_MIDR] = p->midr;
+    miscRegs[MISCREG_MIDR_EL1] = p->midr;
+    miscRegs[MISCREG_VPIDR] = p->midr;
 
+    miscRegs[MISCREG_ID_ISAR0] = p->id_isar0;
+    miscRegs[MISCREG_ID_ISAR1] = p->id_isar1;
+    miscRegs[MISCREG_ID_ISAR2] = p->id_isar2;
+    miscRegs[MISCREG_ID_ISAR3] = p->id_isar3;
+    miscRegs[MISCREG_ID_ISAR4] = p->id_isar4;
+    miscRegs[MISCREG_ID_ISAR5] = p->id_isar5;
+
+    miscRegs[MISCREG_ID_MMFR0] = p->id_mmfr0;
+    miscRegs[MISCREG_ID_MMFR1] = p->id_mmfr1;
+    miscRegs[MISCREG_ID_MMFR2] = p->id_mmfr2;
+    miscRegs[MISCREG_ID_MMFR3] = p->id_mmfr3;
+}
+
+void
+ISA::initID64(const ArmISAParams *p)
+{
     // Initialize configurable id registers
     miscRegs[MISCREG_ID_AA64AFR0_EL1] = p->id_aa64afr0_el1;
     miscRegs[MISCREG_ID_AA64AFR1_EL1] = p->id_aa64afr1_el1;
@@ -326,7 +342,7 @@ ISA::clear64(const ArmISAParams *p)
     // Physical address size
     miscRegs[MISCREG_ID_AA64MMFR0_EL1] = insertBits(
         miscRegs[MISCREG_ID_AA64MMFR0_EL1], 3, 0,
-        encodePhysAddrRange64(physAddrRange64));
+        encodePhysAddrRange64(physAddrRange));
 }
 
 void
diff --git a/src/arch/arm/isa.hh b/src/arch/arm/isa.hh
index 7b39682f9..ae35d704c 100644
--- a/src/arch/arm/isa.hh
+++ b/src/arch/arm/isa.hh
@@ -88,7 +88,7 @@ namespace ArmISA
         bool haveLPAE;
         bool haveVirtualization;
         bool haveLargeAsid64;
-        uint8_t physAddrRange64;
+        uint8_t physAddrRange;
 
         /**
          * If true, accesses to IMPLEMENTATION DEFINED registers are treated
@@ -409,8 +409,13 @@ namespace ArmISA
 
       public:
         void clear();
+
+      protected:
         void clear64(const ArmISAParams *p);
+        void initID32(const ArmISAParams *p);
+        void initID64(const ArmISAParams *p);
 
+      public:
         MiscReg readMiscRegNoEffect(int misc_reg) const;
         MiscReg readMiscReg(int misc_reg, ThreadContext *tc);
         void setMiscRegNoEffect(int misc_reg, const MiscReg &val);
@@ -642,7 +647,7 @@ namespace ArmISA
             SERIALIZE_SCALAR(haveLPAE);
             SERIALIZE_SCALAR(haveVirtualization);
             SERIALIZE_SCALAR(haveLargeAsid64);
-            SERIALIZE_SCALAR(physAddrRange64);
+            SERIALIZE_SCALAR(physAddrRange);
         }
         void unserialize(CheckpointIn &cp)
         {
@@ -656,7 +661,7 @@ namespace ArmISA
             UNSERIALIZE_SCALAR(haveLPAE);
             UNSERIALIZE_SCALAR(haveVirtualization);
             UNSERIALIZE_SCALAR(haveLargeAsid64);
-            UNSERIALIZE_SCALAR(physAddrRange64);
+            UNSERIALIZE_SCALAR(physAddrRange);
         }
 
         void startup(ThreadContext *tc);