From 766dccbad9f6334f931a45195ed57a14cc997273 Mon Sep 17 00:00:00 2001
From: "Edgar E. Iglesias" <edgar.iglesias@xilinx.com>
Date: Thu, 15 Feb 2018 12:41:31 -0500
Subject: [PATCH] target-arm: Add VPIDR_EL2

Backports commit 731de9e60074620aa7d565f01f989adacd493514 from qemu
---
 qemu/target-arm/cpu.h    |  1 +
 qemu/target-arm/helper.c | 36 ++++++++++++++++++++++++++++++++++--
 2 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/qemu/target-arm/cpu.h b/qemu/target-arm/cpu.h
index 1fae1ab5..7b3a2774 100644
--- a/qemu/target-arm/cpu.h
+++ b/qemu/target-arm/cpu.h
@@ -389,6 +389,7 @@ typedef struct CPUARMState {
          */
         uint64_t c15_ccnt;
         uint64_t pmccfiltr_el0; /* Performance Monitor Filter Register */
+        uint64_t vpidr_el2; /* Virtualization Processor ID Register */
     } cp15;
 
     struct {
diff --git a/qemu/target-arm/helper.c b/qemu/target-arm/helper.c
index 3163e5b3..2f56376d 100644
--- a/qemu/target-arm/helper.c
+++ b/qemu/target-arm/helper.c
@@ -2136,6 +2136,18 @@ static const ARMCPRegInfo strongarm_cp_reginfo[] = {
     REGINFO_SENTINEL
 };
 
+static uint64_t midr_read(CPUARMState *env, const ARMCPRegInfo *ri)
+{
+    ARMCPU *cpu = arm_env_get_cpu(env);
+    unsigned int cur_el = arm_current_el(env);
+    bool secure = arm_is_secure(env);
+
+    if (arm_feature(&cpu->env, ARM_FEATURE_EL2) && !secure && cur_el == 1) {
+        return env->cp15.vpidr_el2;
+    }
+    return raw_read(env, ri);
+}
+
 static uint64_t mpidr_read(CPUARMState *env, const ARMCPRegInfo *ri)
 {
     ARMCPU *cpu = ARM_CPU(env->uc, arm_env_get_cpu(env));
@@ -3561,6 +3573,15 @@ void register_cp_regs_for_features(ARMCPU *cpu)
         define_arm_cp_regs(cpu, v8_cp_reginfo);
     }
     if (arm_feature(env, ARM_FEATURE_EL2)) {
+        ARMCPRegInfo vpidr_regs[] = {
+            { "VPIDR", 15,0,0, 0,4,0, ARM_CP_STATE_AA32, 0,
+              PL2_RW, 0, NULL, cpu->midr, offsetof(CPUARMState, cp15.vpidr_el2), {0, 0},
+              access_el3_aa32ns },
+            { "VPIDR_EL2", 0,0,0, 3,4,0, ARM_CP_STATE_AA64, 0,
+              PL2_RW, 0, NULL, cpu->midr, offsetof(CPUARMState, cp15.vpidr_el2) },
+            REGINFO_SENTINEL
+        };
+        define_arm_cp_regs(cpu, vpidr_regs);
         define_arm_cp_regs(cpu, el2_cp_reginfo);
         /* RVBAR_EL2 is only implemented if EL2 is the highest EL */
         if (!arm_feature(env, ARM_FEATURE_EL3)) {
@@ -3575,6 +3596,16 @@ void register_cp_regs_for_features(ARMCPU *cpu)
          * register the no_el2 reginfos.
          */
         if (arm_feature(env, ARM_FEATURE_EL3)) {
+            /* When EL3 exists but not EL2, VPIDR takes the value
+             * of MIDR_EL1.
+             */
+            ARMCPRegInfo vpidr_regs[] = {
+                { "VPIDR_EL2", 0,0,0, 3,4,0, ARM_CP_STATE_BOTH, ARM_CP_CONST,
+                  PL2_RW, 0, NULL, cpu->midr, offsetof(CPUARMState, cp15.vpidr_el2), {0, 0},
+                  access_el3_aa32ns_aa64any },
+                REGINFO_SENTINEL
+            };
+            define_arm_cp_regs(cpu, vpidr_regs);
             define_arm_cp_regs(cpu, el3_no_el2_cp_reginfo);
         }
     }
@@ -3649,7 +3680,7 @@ void register_cp_regs_for_features(ARMCPU *cpu)
              */
             { "MIDR", 15,0,0, 0,0,CP_ANY, 0,
               ARM_CP_OVERRIDE, PL1_R, 0, NULL, cpu->midr, offsetof(CPUARMState, cp15.c0_cpuid), {0, 0},
-              NULL, NULL,arm_cp_write_ignore, NULL,raw_write, },
+              NULL, midr_read, arm_cp_write_ignore, NULL, raw_write, },
             /* crn = 0 op1 = 0 crm = 3..7 : currently unassigned; we RAZ. */
             { "DUMMY",
               15,0,3, 0,0,CP_ANY, 0,
@@ -3670,7 +3701,8 @@ void register_cp_regs_for_features(ARMCPU *cpu)
         };
         ARMCPRegInfo id_v8_midr_cp_reginfo[] = {
             { "MIDR_EL1", 0,0,0, 3,0,0, ARM_CP_STATE_BOTH,
-              ARM_CP_CONST, PL1_R, 0, NULL, cpu->midr },
+              ARM_CP_NO_RAW, PL1_R, 0, NULL, cpu->midr, offsetof(CPUARMState, cp15.c0_cpuid), {0, 0},
+              NULL, midr_read },
             /* crn = 0 op1 = 0 crm = 0 op2 = 4,7 : AArch32 aliases of MIDR */
             { "MIDR", 15,0,0, 0,0,4, 0, ARM_CP_ALIAS | ARM_CP_CONST,
               PL1_R, 0, NULL, cpu->midr },