diff mbox series

[2/2] target/arm: Remove no-longer-reachable 32-bit KVM code

Message ID 20200904154156.31943-3-peter.maydell@linaro.org
State New
Headers show
Series Remove KVM support for 32-bit Arm hosts | expand

Commit Message

Peter Maydell Sept. 4, 2020, 3:41 p.m. UTC 
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>
---
 target/arm/kvm-consts.h |   7 ---
 target/arm/kvm_arm.h    |   6 ---
 target/arm/cpu.c        | 100 ++++++++++++++++++----------------------
 target/arm/kvm.c        |   7 ---
 4 files changed, 46 insertions(+), 74 deletions(-)

Comments

Philippe Mathieu-Daudé Sept. 4, 2020, 4:01 p.m. UTC | #1 
On 9/4/20 5:41 PM, Peter Maydell wrote:
> 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>
> ---
[...]
>  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);
> +    cortex_a15_initfn(obj);
>  
> -        /* old-style VFP short-vector support */
> -        cpu->isar.mvfr0 = FIELD_DP32(cpu->isar.mvfr0, MVFR0, FPSHVEC, 1);
> +    /* 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,
> -         * since we don't correctly set (all of) the ID registers to
> -         * advertise them.
> -         */
> -        set_feature(&cpu->env, ARM_FEATURE_V8);
> -        {
> -            uint32_t t;
> +    /* We don't set these in system emulation mode for the moment,

checkpatch might warn "block comment ... separate line" :/

> +     * since we don't correctly set (all of) the ID registers to
> +     * advertise them.
> +     */
> +    set_feature(&cpu->env, ARM_FEATURE_V8);
> +    {
> +        uint32_t t;
>  
> -            t = cpu->isar.id_isar5;
> -            t = FIELD_DP32(t, ID_ISAR5, AES, 2);
> -            t = FIELD_DP32(t, ID_ISAR5, SHA1, 1);
> -            t = FIELD_DP32(t, ID_ISAR5, SHA2, 1);
> -            t = FIELD_DP32(t, ID_ISAR5, CRC32, 1);
> -            t = FIELD_DP32(t, ID_ISAR5, RDM, 1);
> -            t = FIELD_DP32(t, ID_ISAR5, VCMA, 1);
> -            cpu->isar.id_isar5 = t;
> +        t = cpu->isar.id_isar5;
> +        t = FIELD_DP32(t, ID_ISAR5, AES, 2);
> +        t = FIELD_DP32(t, ID_ISAR5, SHA1, 1);
> +        t = FIELD_DP32(t, ID_ISAR5, SHA2, 1);
> +        t = FIELD_DP32(t, ID_ISAR5, CRC32, 1);
> +        t = FIELD_DP32(t, ID_ISAR5, RDM, 1);
> +        t = FIELD_DP32(t, ID_ISAR5, VCMA, 1);
> +        cpu->isar.id_isar5 = t;
>  
> -            t = cpu->isar.id_isar6;
> -            t = FIELD_DP32(t, ID_ISAR6, JSCVT, 1);
> -            t = FIELD_DP32(t, ID_ISAR6, DP, 1);
> -            t = FIELD_DP32(t, ID_ISAR6, FHM, 1);
> -            t = FIELD_DP32(t, ID_ISAR6, SB, 1);
> -            t = FIELD_DP32(t, ID_ISAR6, SPECRES, 1);
> -            cpu->isar.id_isar6 = t;
> +        t = cpu->isar.id_isar6;
> +        t = FIELD_DP32(t, ID_ISAR6, JSCVT, 1);
> +        t = FIELD_DP32(t, ID_ISAR6, DP, 1);
> +        t = FIELD_DP32(t, ID_ISAR6, FHM, 1);
> +        t = FIELD_DP32(t, ID_ISAR6, SB, 1);
> +        t = FIELD_DP32(t, ID_ISAR6, SPECRES, 1);
> +        cpu->isar.id_isar6 = t;
>  
> -            t = cpu->isar.mvfr1;
> -            t = FIELD_DP32(t, MVFR1, FPHP, 3);     /* v8.2-FP16 */
> -            t = FIELD_DP32(t, MVFR1, SIMDHP, 2);   /* v8.2-FP16 */
> -            cpu->isar.mvfr1 = t;
> +        t = cpu->isar.mvfr1;
> +        t = FIELD_DP32(t, MVFR1, FPHP, 3);     /* v8.2-FP16 */
> +        t = FIELD_DP32(t, MVFR1, SIMDHP, 2);   /* v8.2-FP16 */
> +        cpu->isar.mvfr1 = t;
>  
> -            t = cpu->isar.mvfr2;
> -            t = FIELD_DP32(t, MVFR2, SIMDMISC, 3); /* SIMD MaxNum */
> -            t = FIELD_DP32(t, MVFR2, FPMISC, 4);   /* FP MaxNum */
> -            cpu->isar.mvfr2 = t;
> +        t = cpu->isar.mvfr2;
> +        t = FIELD_DP32(t, MVFR2, SIMDMISC, 3); /* SIMD MaxNum */
> +        t = FIELD_DP32(t, MVFR2, FPMISC, 4);   /* FP MaxNum */
> +        cpu->isar.mvfr2 = t;
>  
> -            t = cpu->isar.id_mmfr3;
> -            t = FIELD_DP32(t, ID_MMFR3, PAN, 2); /* ATS1E1 */
> -            cpu->isar.id_mmfr3 = t;
> +        t = cpu->isar.id_mmfr3;
> +        t = FIELD_DP32(t, ID_MMFR3, PAN, 2); /* ATS1E1 */
> +        cpu->isar.id_mmfr3 = t;
>  
> -            t = cpu->isar.id_mmfr4;
> -            t = FIELD_DP32(t, ID_MMFR4, HPDS, 1); /* AA32HPD */
> -            t = FIELD_DP32(t, ID_MMFR4, AC2, 1); /* ACTLR2, HACTLR2 */
> -            t = FIELD_DP32(t, ID_MMFR4, CNP, 1); /* TTCNP */
> -            t = FIELD_DP32(t, ID_MMFR4, XNX, 1); /* TTS2UXN */
> -            cpu->isar.id_mmfr4 = t;
> -        }
> -#endif
> +        t = cpu->isar.id_mmfr4;
> +        t = FIELD_DP32(t, ID_MMFR4, HPDS, 1); /* AA32HPD */
> +        t = FIELD_DP32(t, ID_MMFR4, AC2, 1); /* ACTLR2, HACTLR2 */
> +        t = FIELD_DP32(t, ID_MMFR4, CNP, 1); /* TTCNP */
> +        t = FIELD_DP32(t, ID_MMFR4, XNX, 1); /* TTS2UXN */
> +        cpu->isar.id_mmfr4 = t;
>      }
> +#endif

Scary :) This is the if {} else {} removed, OK.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

>  }
>  #endif
>  
> @@ -2269,11 +2265,7 @@ 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,
>  };
[...]
Peter Maydell Sept. 4, 2020, 4:06 p.m. UTC | #2 
On Fri, 4 Sep 2020 at 17:01, Philippe Mathieu-Daudé <philmd@redhat.com> wrote:
> Scary :) This is the if {} else {} removed, OK.

Mmm. It would be nice if there was a patch syntax for
"indent or dedent lines X to Y by N spaces", but I guess
we're several decades too late to add such things.

thanks
-- PMM
diff mbox series

Patch

diff --git a/target/arm/kvm-consts.h b/target/arm/kvm-consts.h
index aad28258a36..580f1c1fee0 100644
--- a/target/arm/kvm-consts.h
+++ b/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
 
diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
index adb38514bf2..bc178eeb84c 100644
--- a/target/arm/kvm_arm.h
+++ b/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");
diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index c179e0752da..cb1fa2a35c3 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -2099,72 +2099,68 @@  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);
+    cortex_a15_initfn(obj);
 
-        /* old-style VFP short-vector support */
-        cpu->isar.mvfr0 = FIELD_DP32(cpu->isar.mvfr0, MVFR0, FPSHVEC, 1);
+    /* 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,
-         * since we don't correctly set (all of) the ID registers to
-         * advertise them.
-         */
-        set_feature(&cpu->env, ARM_FEATURE_V8);
-        {
-            uint32_t t;
+    /* 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.
+     */
+    set_feature(&cpu->env, ARM_FEATURE_V8);
+    {
+        uint32_t t;
 
-            t = cpu->isar.id_isar5;
-            t = FIELD_DP32(t, ID_ISAR5, AES, 2);
-            t = FIELD_DP32(t, ID_ISAR5, SHA1, 1);
-            t = FIELD_DP32(t, ID_ISAR5, SHA2, 1);
-            t = FIELD_DP32(t, ID_ISAR5, CRC32, 1);
-            t = FIELD_DP32(t, ID_ISAR5, RDM, 1);
-            t = FIELD_DP32(t, ID_ISAR5, VCMA, 1);
-            cpu->isar.id_isar5 = t;
+        t = cpu->isar.id_isar5;
+        t = FIELD_DP32(t, ID_ISAR5, AES, 2);
+        t = FIELD_DP32(t, ID_ISAR5, SHA1, 1);
+        t = FIELD_DP32(t, ID_ISAR5, SHA2, 1);
+        t = FIELD_DP32(t, ID_ISAR5, CRC32, 1);
+        t = FIELD_DP32(t, ID_ISAR5, RDM, 1);
+        t = FIELD_DP32(t, ID_ISAR5, VCMA, 1);
+        cpu->isar.id_isar5 = t;
 
-            t = cpu->isar.id_isar6;
-            t = FIELD_DP32(t, ID_ISAR6, JSCVT, 1);
-            t = FIELD_DP32(t, ID_ISAR6, DP, 1);
-            t = FIELD_DP32(t, ID_ISAR6, FHM, 1);
-            t = FIELD_DP32(t, ID_ISAR6, SB, 1);
-            t = FIELD_DP32(t, ID_ISAR6, SPECRES, 1);
-            cpu->isar.id_isar6 = t;
+        t = cpu->isar.id_isar6;
+        t = FIELD_DP32(t, ID_ISAR6, JSCVT, 1);
+        t = FIELD_DP32(t, ID_ISAR6, DP, 1);
+        t = FIELD_DP32(t, ID_ISAR6, FHM, 1);
+        t = FIELD_DP32(t, ID_ISAR6, SB, 1);
+        t = FIELD_DP32(t, ID_ISAR6, SPECRES, 1);
+        cpu->isar.id_isar6 = t;
 
-            t = cpu->isar.mvfr1;
-            t = FIELD_DP32(t, MVFR1, FPHP, 3);     /* v8.2-FP16 */
-            t = FIELD_DP32(t, MVFR1, SIMDHP, 2);   /* v8.2-FP16 */
-            cpu->isar.mvfr1 = t;
+        t = cpu->isar.mvfr1;
+        t = FIELD_DP32(t, MVFR1, FPHP, 3);     /* v8.2-FP16 */
+        t = FIELD_DP32(t, MVFR1, SIMDHP, 2);   /* v8.2-FP16 */
+        cpu->isar.mvfr1 = t;
 
-            t = cpu->isar.mvfr2;
-            t = FIELD_DP32(t, MVFR2, SIMDMISC, 3); /* SIMD MaxNum */
-            t = FIELD_DP32(t, MVFR2, FPMISC, 4);   /* FP MaxNum */
-            cpu->isar.mvfr2 = t;
+        t = cpu->isar.mvfr2;
+        t = FIELD_DP32(t, MVFR2, SIMDMISC, 3); /* SIMD MaxNum */
+        t = FIELD_DP32(t, MVFR2, FPMISC, 4);   /* FP MaxNum */
+        cpu->isar.mvfr2 = t;
 
-            t = cpu->isar.id_mmfr3;
-            t = FIELD_DP32(t, ID_MMFR3, PAN, 2); /* ATS1E1 */
-            cpu->isar.id_mmfr3 = t;
+        t = cpu->isar.id_mmfr3;
+        t = FIELD_DP32(t, ID_MMFR3, PAN, 2); /* ATS1E1 */
+        cpu->isar.id_mmfr3 = t;
 
-            t = cpu->isar.id_mmfr4;
-            t = FIELD_DP32(t, ID_MMFR4, HPDS, 1); /* AA32HPD */
-            t = FIELD_DP32(t, ID_MMFR4, AC2, 1); /* ACTLR2, HACTLR2 */
-            t = FIELD_DP32(t, ID_MMFR4, CNP, 1); /* TTCNP */
-            t = FIELD_DP32(t, ID_MMFR4, XNX, 1); /* TTS2UXN */
-            cpu->isar.id_mmfr4 = t;
-        }
-#endif
+        t = cpu->isar.id_mmfr4;
+        t = FIELD_DP32(t, ID_MMFR4, HPDS, 1); /* AA32HPD */
+        t = FIELD_DP32(t, ID_MMFR4, AC2, 1); /* ACTLR2, HACTLR2 */
+        t = FIELD_DP32(t, ID_MMFR4, CNP, 1); /* TTCNP */
+        t = FIELD_DP32(t, ID_MMFR4, XNX, 1); /* TTS2UXN */
+        cpu->isar.id_mmfr4 = t;
     }
+#endif
 }
 #endif
 
@@ -2269,11 +2265,7 @@  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,
 };
 
diff --git a/target/arm/kvm.c b/target/arm/kvm.c
index 8bb7318378b..2eae73315d6 100644
--- a/target/arm/kvm.c
+++ b/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)