target/arm: Remove no-longer-reachable 32-bit KVM code

Now that 32-bit KVM host support is gone, KVM can never
be enabled unless CONFIG_AARCH64 is true, and some code
paths are no longer reachable and can be deleted.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200904154156.31943-3-peter.maydell@linaro.org

target/arm/cpu.c

@@ -2098,25 +2098,23 @@ static void cortex_a15_initfn(Object *obj)
 }
 
 #ifndef TARGET_AARCH64
-/* -cpu max: if KVM is enabled, like -cpu host (best possible with this host);
+/*
- * otherwise, a CPU with as many features enabled as our emulation supports.
+ * -cpu max: a CPU with as many features enabled as our emulation supports.
  * The version of '-cpu max' for qemu-system-aarch64 is defined in cpu64.c;
- * this only needs to handle 32 bits.
+ * this only needs to handle 32 bits, and need not care about KVM.
  */
 static void arm_max_initfn(Object *obj)
 {
     ARMCPU *cpu = ARM_CPU(obj);
 
-    if (kvm_enabled()) {
-        kvm_arm_set_cpu_features_from_host(cpu);
-    } else {
     cortex_a15_initfn(obj);
 
     /* old-style VFP short-vector support */
     cpu->isar.mvfr0 = FIELD_DP32(cpu->isar.mvfr0, MVFR0, FPSHVEC, 1);
 
 #ifdef CONFIG_USER_ONLY
-        /* We don't set these in system emulation mode for the moment,
+    /*
+     * We don't set these in system emulation mode for the moment,
      * since we don't correctly set (all of) the ID registers to
      * advertise them.
      */
@@ -2164,7 +2162,6 @@ static void arm_max_initfn(Object *obj)
     }
 #endif
 }
-}
 #endif
 
 #endif /* !defined(CONFIG_USER_ONLY) || !defined(TARGET_AARCH64) */
@@ -2267,11 +2264,7 @@ static void arm_host_initfn(Object *obj)
 
 static const TypeInfo host_arm_cpu_type_info = {
     .name = TYPE_ARM_HOST_CPU,
-#ifdef TARGET_AARCH64
     .parent = TYPE_AARCH64_CPU,
-#else
-    .parent = TYPE_ARM_CPU,
-#endif
     .instance_init = arm_host_initfn,
 };
 

target/arm/kvm-consts.h

@@ -136,16 +136,11 @@ MISMATCH_CHECK(QEMU_PSCI_RET_DISABLED, PSCI_RET_DISABLED);
  */
 #define QEMU_KVM_ARM_TARGET_NONE UINT_MAX
 
-#ifdef TARGET_AARCH64
 MISMATCH_CHECK(QEMU_KVM_ARM_TARGET_AEM_V8, KVM_ARM_TARGET_AEM_V8);
 MISMATCH_CHECK(QEMU_KVM_ARM_TARGET_FOUNDATION_V8, KVM_ARM_TARGET_FOUNDATION_V8);
 MISMATCH_CHECK(QEMU_KVM_ARM_TARGET_CORTEX_A57, KVM_ARM_TARGET_CORTEX_A57);
 MISMATCH_CHECK(QEMU_KVM_ARM_TARGET_XGENE_POTENZA, KVM_ARM_TARGET_XGENE_POTENZA);
 MISMATCH_CHECK(QEMU_KVM_ARM_TARGET_CORTEX_A53, KVM_ARM_TARGET_CORTEX_A53);
-#else
-MISMATCH_CHECK(QEMU_KVM_ARM_TARGET_CORTEX_A15, KVM_ARM_TARGET_CORTEX_A15);
-MISMATCH_CHECK(QEMU_KVM_ARM_TARGET_CORTEX_A7, KVM_ARM_TARGET_CORTEX_A7);
-#endif
 
 #define CP_REG_ARM64                   0x6000000000000000ULL
 #define CP_REG_ARM_COPROC_MASK         0x000000000FFF0000
@@ -165,7 +160,6 @@ MISMATCH_CHECK(QEMU_KVM_ARM_TARGET_CORTEX_A7, KVM_ARM_TARGET_CORTEX_A7);
 /* No kernel define but it's useful to QEMU */
 #define CP_REG_ARM64_SYSREG_CP (CP_REG_ARM64_SYSREG >> CP_REG_ARM_COPROC_SHIFT)
 
-#ifdef TARGET_AARCH64
 MISMATCH_CHECK(CP_REG_ARM64, KVM_REG_ARM64);
 MISMATCH_CHECK(CP_REG_ARM_COPROC_MASK, KVM_REG_ARM_COPROC_MASK);
 MISMATCH_CHECK(CP_REG_ARM_COPROC_SHIFT, KVM_REG_ARM_COPROC_SHIFT);
@@ -180,7 +174,6 @@ MISMATCH_CHECK(CP_REG_ARM64_SYSREG_CRM_MASK, KVM_REG_ARM64_SYSREG_CRM_MASK);
 MISMATCH_CHECK(CP_REG_ARM64_SYSREG_CRM_SHIFT, KVM_REG_ARM64_SYSREG_CRM_SHIFT);
 MISMATCH_CHECK(CP_REG_ARM64_SYSREG_OP2_MASK, KVM_REG_ARM64_SYSREG_OP2_MASK);
 MISMATCH_CHECK(CP_REG_ARM64_SYSREG_OP2_SHIFT, KVM_REG_ARM64_SYSREG_OP2_SHIFT);
-#endif
 
 #undef MISMATCH_CHECK
 

target/arm/kvm.c

@@ -918,22 +918,15 @@ int kvm_arch_process_async_events(CPUState *cs)
     return 0;
 }
 
-/* The #ifdef protections are until 32bit headers are imported and can
- * be removed once both 32 and 64 bit reach feature parity.
- */
 void kvm_arch_update_guest_debug(CPUState *cs, struct kvm_guest_debug *dbg)
 {
-#ifdef KVM_GUESTDBG_USE_SW_BP
     if (kvm_sw_breakpoints_active(cs)) {
         dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP;
     }
-#endif
-#ifdef KVM_GUESTDBG_USE_HW
     if (kvm_arm_hw_debug_active(cs)) {
         dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_HW;
         kvm_arm_copy_hw_debug_data(&dbg->arch);
     }
-#endif
 }
 
 void kvm_arch_init_irq_routing(KVMState *s)

target/arm/kvm_arm.h

@@ -406,13 +406,7 @@ static inline const char *gic_class_name(void)
 static inline const char *gicv3_class_name(void)
 {
     if (kvm_irqchip_in_kernel()) {
-#ifdef TARGET_AARCH64
         return "kvm-arm-gicv3";
-#else
-        error_report("KVM GICv3 acceleration is not supported on this "
-                     "platform");
-        exit(1);
-#endif
     } else {
         if (kvm_enabled()) {
             error_report("Userspace GICv3 is not supported with KVM");