target-arm: Add VTTBR_EL2

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1442135278-25281-4-git-send-email-edgar.iglesias@gmail.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
diff --git a/target-arm/cpu.h b/target-arm/cpu.h
index f91b793..96b8f2a 100644
--- a/target-arm/cpu.h
+++ b/target-arm/cpu.h
@@ -222,6 +222,7 @@
             };
             uint64_t ttbr1_el[4];
         };
+        uint64_t vttbr_el2; /* Virtualization Translation Table Base.  */
         /* MMU translation table base control. */
         TCR tcr_el[4];
         TCR vtcr_el2; /* Virtualization Translation Control.  */
diff --git a/target-arm/helper.c b/target-arm/helper.c
index b250ed0..d84f3c9 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -2213,6 +2213,20 @@
     raw_write(env, ri, value);
 }
 
+static void vttbr_write(CPUARMState *env, const ARMCPRegInfo *ri,
+                        uint64_t value)
+{
+    ARMCPU *cpu = arm_env_get_cpu(env);
+    CPUState *cs = CPU(cpu);
+
+    /* Accesses to VTTBR may change the VMID so we must flush the TLB.  */
+    if (raw_read(env, ri) != value) {
+        tlb_flush_by_mmuidx(cs, ARMMMUIdx_S12NSE1, ARMMMUIdx_S12NSE0,
+                            ARMMMUIdx_S2NS, -1);
+        raw_write(env, ri, value);
+    }
+}
+
 static const ARMCPRegInfo vmsa_pmsa_cp_reginfo[] = {
     { .name = "DFSR", .cp = 15, .crn = 5, .crm = 0, .opc1 = 0, .opc2 = 0,
       .access = PL1_RW, .type = ARM_CP_ALIAS,
@@ -3144,6 +3158,13 @@
       .opc0 = 3, .opc1 = 4, .crn = 2, .crm = 1, .opc2 = 2,
       .access = PL2_RW, .accessfn = access_el3_aa32ns_aa64any,
       .type = ARM_CP_CONST, .resetvalue = 0 },
+    { .name = "VTTBR", .state = ARM_CP_STATE_AA32,
+      .cp = 15, .opc1 = 6, .crm = 2,
+      .access = PL2_RW, .accessfn = access_el3_aa32ns,
+      .type = ARM_CP_CONST | ARM_CP_64BIT, .resetvalue = 0 },
+    { .name = "VTTBR_EL2", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 4, .crn = 2, .crm = 1, .opc2 = 0,
+      .access = PL2_RW, .type = ARM_CP_CONST, .resetvalue = 0 },
     { .name = "SCTLR_EL2", .state = ARM_CP_STATE_BOTH,
       .opc0 = 3, .opc1 = 4, .crn = 1, .crm = 0, .opc2 = 0,
       .access = PL2_RW, .type = ARM_CP_CONST, .resetvalue = 0 },
@@ -3286,6 +3307,16 @@
       .opc0 = 3, .opc1 = 4, .crn = 2, .crm = 1, .opc2 = 2,
       .access = PL2_RW, .type = ARM_CP_ALIAS,
       .fieldoffset = offsetof(CPUARMState, cp15.vtcr_el2) },
+    { .name = "VTTBR", .state = ARM_CP_STATE_AA32,
+      .cp = 15, .opc1 = 6, .crm = 2,
+      .type = ARM_CP_64BIT | ARM_CP_ALIAS,
+      .access = PL2_RW, .accessfn = access_el3_aa32ns,
+      .fieldoffset = offsetof(CPUARMState, cp15.vttbr_el2),
+      .writefn = vttbr_write },
+    { .name = "VTTBR_EL2", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 4, .crn = 2, .crm = 1, .opc2 = 0,
+      .access = PL2_RW, .writefn = vttbr_write,
+      .fieldoffset = offsetof(CPUARMState, cp15.vttbr_el2) },
     { .name = "SCTLR_EL2", .state = ARM_CP_STATE_BOTH,
       .opc0 = 3, .opc1 = 4, .crn = 1, .crm = 0, .opc2 = 0,
       .access = PL2_RW, .raw_writefn = raw_write, .writefn = sctlr_write,
@@ -5791,8 +5822,7 @@
                                    int ttbrn)
 {
     if (mmu_idx == ARMMMUIdx_S2NS) {
-        /* TODO: return VTTBR_EL2 */
-        g_assert_not_reached();
+        return env->cp15.vttbr_el2;
     }
     if (ttbrn == 0) {
         return env->cp15.ttbr0_el[regime_el(env, mmu_idx)];