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[Qemu-devel] [PATCH v2 4/6] target/arm: Make 'any' CPU just an alias for 'max'

Peter Maydell posted 6 patches 7 years, 7 months ago
There is a newer version of this series
[Qemu-devel] [PATCH v2 4/6] target/arm: Make 'any' CPU just an alias for 'max'
Posted by Peter Maydell 7 years, 7 months ago 
Now we have a working '-cpu max', the linux-user-only
'any' CPU is pretty much the same thing, so implement it
that way.

For the moment we don't add any of the extra feature bits
to the system-emulation "max", because we don't set the
ID register bits we would need to to advertise those
features as present.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/cpu.c   | 50 +++++++++++++++++++++++----------------------
 target/arm/cpu64.c | 59 ++++++++++++++++++++++++++----------------------------
 2 files changed, 54 insertions(+), 55 deletions(-)

diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index e46ddcc613..c8d3da2140 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -965,9 +965,17 @@ static ObjectClass *arm_cpu_class_by_name(const char *cpu_model)
     ObjectClass *oc;
     char *typename;
     char **cpuname;
+    const char *cpunamestr;
 
     cpuname = g_strsplit(cpu_model, ",", 1);
-    typename = g_strdup_printf(ARM_CPU_TYPE_NAME("%s"), cpuname[0]);
+    cpunamestr = cpuname[0];
+#ifdef CONFIG_USER_ONLY
+    /* For backwards compatibility usermode emulation allows "-cpu any",
+     * which has the same semantics as "-cpu max".
+     */
+    cpunamestr = "max";
+#endif
+    typename = g_strdup_printf(ARM_CPU_TYPE_NAME("%s"), cpunamestr);
     oc = object_class_by_name(typename);
     g_strfreev(cpuname);
     g_free(typename);
@@ -1711,29 +1719,23 @@ static void arm_max_initfn(Object *obj)
         kvm_arm_set_cpu_features_from_host(cpu);
     } else {
         cortex_a15_initfn(obj);
-        /* In future we might add feature bits here even if the
-         * real-world A15 doesn't implement them.
-         */
-    }
-}
-#endif
-
 #ifdef CONFIG_USER_ONLY
-static void arm_any_initfn(Object *obj)
-{
-    ARMCPU *cpu = ARM_CPU(obj);
-    set_feature(&cpu->env, ARM_FEATURE_V8);
-    set_feature(&cpu->env, ARM_FEATURE_VFP4);
-    set_feature(&cpu->env, ARM_FEATURE_NEON);
-    set_feature(&cpu->env, ARM_FEATURE_THUMB2EE);
-    set_feature(&cpu->env, ARM_FEATURE_V8_AES);
-    set_feature(&cpu->env, ARM_FEATURE_V8_SHA1);
-    set_feature(&cpu->env, ARM_FEATURE_V8_SHA256);
-    set_feature(&cpu->env, ARM_FEATURE_V8_PMULL);
-    set_feature(&cpu->env, ARM_FEATURE_CRC);
-    set_feature(&cpu->env, ARM_FEATURE_V8_RDM);
-    set_feature(&cpu->env, ARM_FEATURE_V8_FCMA);
-    cpu->midr = 0xffffffff;
+        /* We don't set these in system emulation mode for the moment,
+         * since we don't correctly set the ID registers to advertise them,
+         */
+        set_feature(&cpu->env, ARM_FEATURE_V8);
+        set_feature(&cpu->env, ARM_FEATURE_VFP4);
+        set_feature(&cpu->env, ARM_FEATURE_NEON);
+        set_feature(&cpu->env, ARM_FEATURE_THUMB2EE);
+        set_feature(&cpu->env, ARM_FEATURE_V8_AES);
+        set_feature(&cpu->env, ARM_FEATURE_V8_SHA1);
+        set_feature(&cpu->env, ARM_FEATURE_V8_SHA256);
+        set_feature(&cpu->env, ARM_FEATURE_V8_PMULL);
+        set_feature(&cpu->env, ARM_FEATURE_CRC);
+        set_feature(&cpu->env, ARM_FEATURE_V8_RDM);
+        set_feature(&cpu->env, ARM_FEATURE_V8_FCMA);
+#endif
+    }
 }
 #endif
 
@@ -1789,7 +1791,7 @@ static const ARMCPUInfo arm_cpus[] = {
     { .name = "max",         .initfn = arm_max_initfn },
 #endif
 #ifdef CONFIG_USER_ONLY
-    { .name = "any",         .initfn = arm_any_initfn },
+    { .name = "any",         .initfn = arm_max_initfn },
 #endif
 #endif
     { .name = NULL }
diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
index 9042d3dfd1..3429875787 100644
--- a/target/arm/cpu64.c
+++ b/target/arm/cpu64.c
@@ -226,38 +226,38 @@ static void aarch64_max_initfn(Object *obj)
         kvm_arm_set_cpu_features_from_host(cpu);
     } else {
         aarch64_a57_initfn(obj);
-        /* In future we might add feature bits here even if the
-         * real-world A57 doesn't implement them.
+#ifdef CONFIG_USER_ONLY
+        /* We don't set these in system emulation mode for the moment,
+         * since we don't correctly set the ID registers to advertise them,
+         * and in some cases they're only available in AArch64 and not AArch32,
+         * whereas the architecture requires them to be present in both if
+         * present in either.
          */
+        set_feature(&cpu->env, ARM_FEATURE_V8);
+        set_feature(&cpu->env, ARM_FEATURE_VFP4);
+        set_feature(&cpu->env, ARM_FEATURE_NEON);
+        set_feature(&cpu->env, ARM_FEATURE_AARCH64);
+        set_feature(&cpu->env, ARM_FEATURE_V8_AES);
+        set_feature(&cpu->env, ARM_FEATURE_V8_SHA1);
+        set_feature(&cpu->env, ARM_FEATURE_V8_SHA256);
+        set_feature(&cpu->env, ARM_FEATURE_V8_SHA512);
+        set_feature(&cpu->env, ARM_FEATURE_V8_SHA3);
+        set_feature(&cpu->env, ARM_FEATURE_V8_SM3);
+        set_feature(&cpu->env, ARM_FEATURE_V8_SM4);
+        set_feature(&cpu->env, ARM_FEATURE_V8_PMULL);
+        set_feature(&cpu->env, ARM_FEATURE_CRC);
+        set_feature(&cpu->env, ARM_FEATURE_V8_RDM);
+        set_feature(&cpu->env, ARM_FEATURE_V8_FP16);
+        set_feature(&cpu->env, ARM_FEATURE_V8_FCMA);
+        /* For usermode -cpu max we can use a larger and more efficient DCZ
+         * blocksize since we don't have to follow what the hardware does.
+         */
+        cpu->ctr = 0x80038003; /* 32 byte I and D cacheline size, VIPT icache */
+        cpu->dcz_blocksize = 7; /*  512 bytes */
+#endif
     }
 }
 
-#ifdef CONFIG_USER_ONLY
-static void aarch64_any_initfn(Object *obj)
-{
-    ARMCPU *cpu = ARM_CPU(obj);
-
-    set_feature(&cpu->env, ARM_FEATURE_V8);
-    set_feature(&cpu->env, ARM_FEATURE_VFP4);
-    set_feature(&cpu->env, ARM_FEATURE_NEON);
-    set_feature(&cpu->env, ARM_FEATURE_AARCH64);
-    set_feature(&cpu->env, ARM_FEATURE_V8_AES);
-    set_feature(&cpu->env, ARM_FEATURE_V8_SHA1);
-    set_feature(&cpu->env, ARM_FEATURE_V8_SHA256);
-    set_feature(&cpu->env, ARM_FEATURE_V8_SHA512);
-    set_feature(&cpu->env, ARM_FEATURE_V8_SHA3);
-    set_feature(&cpu->env, ARM_FEATURE_V8_SM3);
-    set_feature(&cpu->env, ARM_FEATURE_V8_SM4);
-    set_feature(&cpu->env, ARM_FEATURE_V8_PMULL);
-    set_feature(&cpu->env, ARM_FEATURE_CRC);
-    set_feature(&cpu->env, ARM_FEATURE_V8_RDM);
-    set_feature(&cpu->env, ARM_FEATURE_V8_FP16);
-    set_feature(&cpu->env, ARM_FEATURE_V8_FCMA);
-    cpu->ctr = 0x80038003; /* 32 byte I and D cacheline size, VIPT icache */
-    cpu->dcz_blocksize = 7; /*  512 bytes */
-}
-#endif
-
 typedef struct ARMCPUInfo {
     const char *name;
     void (*initfn)(Object *obj);
@@ -268,9 +268,6 @@ static const ARMCPUInfo aarch64_cpus[] = {
     { .name = "cortex-a57",         .initfn = aarch64_a57_initfn },
     { .name = "cortex-a53",         .initfn = aarch64_a53_initfn },
     { .name = "max",                .initfn = aarch64_max_initfn },
-#ifdef CONFIG_USER_ONLY
-    { .name = "any",         .initfn = aarch64_any_initfn },
-#endif
     { .name = NULL }
 };
 
-- 
2.16.2
Re: [Qemu-devel] [PATCH v2 4/6] target/arm: Make 'any' CPU just an alias for 'max'
Posted by Igor Mammedov 7 years, 7 months ago 
On Tue,  6 Mar 2018 12:55:24 +0000
Peter Maydell <peter.maydell@linaro.org> wrote:

> Now we have a working '-cpu max', the linux-user-only
> 'any' CPU is pretty much the same thing, so implement it
> that way.
> 
> For the moment we don't add any of the extra feature bits
> to the system-emulation "max", because we don't set the
> ID register bits we would need to to advertise those
> features as present.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>  target/arm/cpu.c   | 50 +++++++++++++++++++++++----------------------
>  target/arm/cpu64.c | 59 ++++++++++++++++++++++++++----------------------------
>  2 files changed, 54 insertions(+), 55 deletions(-)
> 
> diff --git a/target/arm/cpu.c b/target/arm/cpu.c
> index e46ddcc613..c8d3da2140 100644
> --- a/target/arm/cpu.c
> +++ b/target/arm/cpu.c
> @@ -965,9 +965,17 @@ static ObjectClass *arm_cpu_class_by_name(const char *cpu_model)
>      ObjectClass *oc;
>      char *typename;
>      char **cpuname;
> +    const char *cpunamestr;
>  
>      cpuname = g_strsplit(cpu_model, ",", 1);
> -    typename = g_strdup_printf(ARM_CPU_TYPE_NAME("%s"), cpuname[0]);
> +    cpunamestr = cpuname[0];
> +#ifdef CONFIG_USER_ONLY
> +    /* For backwards compatibility usermode emulation allows "-cpu any",
> +     * which has the same semantics as "-cpu max".
> +     */
> +    cpunamestr = "max";
shouldn't it be
 if (!strcmp(cpuname[0], "any")) {
     cpunamestr = "max";
 }


> +#endif
> +    typename = g_strdup_printf(ARM_CPU_TYPE_NAME("%s"), cpunamestr);
>      oc = object_class_by_name(typename);
>      g_strfreev(cpuname);
>      g_free(typename);
> @@ -1711,29 +1719,23 @@ static void arm_max_initfn(Object *obj)
>          kvm_arm_set_cpu_features_from_host(cpu);
>      } else {
>          cortex_a15_initfn(obj);
> -        /* In future we might add feature bits here even if the
> -         * real-world A15 doesn't implement them.
> -         */
> -    }
> -}
> -#endif
> -
>  #ifdef CONFIG_USER_ONLY
> -static void arm_any_initfn(Object *obj)
> -{
> -    ARMCPU *cpu = ARM_CPU(obj);
> -    set_feature(&cpu->env, ARM_FEATURE_V8);
> -    set_feature(&cpu->env, ARM_FEATURE_VFP4);
> -    set_feature(&cpu->env, ARM_FEATURE_NEON);
> -    set_feature(&cpu->env, ARM_FEATURE_THUMB2EE);
> -    set_feature(&cpu->env, ARM_FEATURE_V8_AES);
> -    set_feature(&cpu->env, ARM_FEATURE_V8_SHA1);
> -    set_feature(&cpu->env, ARM_FEATURE_V8_SHA256);
> -    set_feature(&cpu->env, ARM_FEATURE_V8_PMULL);
> -    set_feature(&cpu->env, ARM_FEATURE_CRC);
> -    set_feature(&cpu->env, ARM_FEATURE_V8_RDM);
> -    set_feature(&cpu->env, ARM_FEATURE_V8_FCMA);
> -    cpu->midr = 0xffffffff;
> +        /* We don't set these in system emulation mode for the moment,
> +         * since we don't correctly set the ID registers to advertise them,
> +         */
> +        set_feature(&cpu->env, ARM_FEATURE_V8);
> +        set_feature(&cpu->env, ARM_FEATURE_VFP4);
> +        set_feature(&cpu->env, ARM_FEATURE_NEON);
> +        set_feature(&cpu->env, ARM_FEATURE_THUMB2EE);
> +        set_feature(&cpu->env, ARM_FEATURE_V8_AES);
> +        set_feature(&cpu->env, ARM_FEATURE_V8_SHA1);
> +        set_feature(&cpu->env, ARM_FEATURE_V8_SHA256);
> +        set_feature(&cpu->env, ARM_FEATURE_V8_PMULL);
> +        set_feature(&cpu->env, ARM_FEATURE_CRC);
> +        set_feature(&cpu->env, ARM_FEATURE_V8_RDM);
> +        set_feature(&cpu->env, ARM_FEATURE_V8_FCMA);
> +#endif
> +    }
>  }
>  #endif
>  
> @@ -1789,7 +1791,7 @@ static const ARMCPUInfo arm_cpus[] = {
>      { .name = "max",         .initfn = arm_max_initfn },
>  #endif
>  #ifdef CONFIG_USER_ONLY
> -    { .name = "any",         .initfn = arm_any_initfn },
> +    { .name = "any",         .initfn = arm_max_initfn },
Note,
 'any' will disappear from "-cpu help"
but that's probably fine, old users would still be able to use alias
and new ones won't even suspect about its existence and use 'max'.

[...]
Re: [Qemu-devel] [PATCH v2 4/6] target/arm: Make 'any' CPU just an alias for 'max'
Posted by Peter Maydell 7 years, 7 months ago 
On 6 March 2018 at 15:16, Igor Mammedov <imammedo@redhat.com> wrote:
> On Tue,  6 Mar 2018 12:55:24 +0000
> Peter Maydell <peter.maydell@linaro.org> wrote:
>
>> Now we have a working '-cpu max', the linux-user-only
>> 'any' CPU is pretty much the same thing, so implement it
>> that way.
>>
>> For the moment we don't add any of the extra feature bits
>> to the system-emulation "max", because we don't set the
>> ID register bits we would need to to advertise those
>> features as present.
>>
>> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>> ---
>>  target/arm/cpu.c   | 50 +++++++++++++++++++++++----------------------
>>  target/arm/cpu64.c | 59 ++++++++++++++++++++++++++----------------------------
>>  2 files changed, 54 insertions(+), 55 deletions(-)
>>
>> diff --git a/target/arm/cpu.c b/target/arm/cpu.c
>> index e46ddcc613..c8d3da2140 100644
>> --- a/target/arm/cpu.c
>> +++ b/target/arm/cpu.c
>> @@ -965,9 +965,17 @@ static ObjectClass *arm_cpu_class_by_name(const char *cpu_model)
>>      ObjectClass *oc;
>>      char *typename;
>>      char **cpuname;
>> +    const char *cpunamestr;
>>
>>      cpuname = g_strsplit(cpu_model, ",", 1);
>> -    typename = g_strdup_printf(ARM_CPU_TYPE_NAME("%s"), cpuname[0]);
>> +    cpunamestr = cpuname[0];
>> +#ifdef CONFIG_USER_ONLY
>> +    /* For backwards compatibility usermode emulation allows "-cpu any",
>> +     * which has the same semantics as "-cpu max".
>> +     */
>> +    cpunamestr = "max";
> shouldn't it be
>  if (!strcmp(cpuname[0], "any")) {
>      cpunamestr = "max";
>  }

Yes. I shuffled the code around a bit and managed to lose the
comparison...


>> @@ -1789,7 +1791,7 @@ static const ARMCPUInfo arm_cpus[] = {
>>      { .name = "max",         .initfn = arm_max_initfn },
>>  #endif
>>  #ifdef CONFIG_USER_ONLY
>> -    { .name = "any",         .initfn = arm_any_initfn },
>> +    { .name = "any",         .initfn = arm_max_initfn },
> Note,
>  'any' will disappear from "-cpu help"
> but that's probably fine, old users would still be able to use alias
> and new ones won't even suspect about its existence and use 'max'.

Yeah, I guess that's OK.

thanks
-- PMM

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