Re: [Qemu-devel] [PATCH 1/5] target-arm: Add ARM CPU feature parsing

[Igor Mammedov <imammedo@redhat.com>]

On Mon, 19 Jan 2015 16:30:17 -0600
Greg Bellows <greg.bellows@linaro.org> wrote:

> Adds a CPU feature parsing function and assigns to the CPU class.  The only
> feature added was "-aarch64" which disabled the AArch64 execution state on a
> 64-bit ARM CPU.
> 
> Also adds stripping of features from CPU model string in acquiring the ARM CPU
> by name.
> 
> Signed-off-by: Greg Bellows <greg.bellows@linaro.org>
> ---
>  target-arm/cpu.c | 45 ++++++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 44 insertions(+), 1 deletion(-)
> 
> diff --git a/target-arm/cpu.c b/target-arm/cpu.c
> index 285947f..f327dd7 100644
> --- a/target-arm/cpu.c
> +++ b/target-arm/cpu.c
> @@ -514,13 +514,17 @@ static ObjectClass *arm_cpu_class_by_name(const char *cpu_model)
>  {
>      ObjectClass *oc;
>      char *typename;
> +    char *cpuname;
>  
>      if (!cpu_model) {
>          return NULL;
>      }
>  
> -    typename = g_strdup_printf("%s-" TYPE_ARM_CPU, cpu_model);
> +    cpuname = g_strdup(cpu_model);
> +    cpuname = strtok(cpuname, ",");
> +    typename = g_strdup_printf("%s-" TYPE_ARM_CPU, cpuname);
>      oc = object_class_by_name(typename);
> +    g_free(cpuname);
>      g_free(typename);
>      if (!oc || !object_class_dynamic_cast(oc, TYPE_ARM_CPU) ||
>          object_class_is_abstract(oc)) {
> @@ -1163,6 +1167,44 @@ static Property arm_cpu_properties[] = {
>      DEFINE_PROP_END_OF_LIST()
>  };
>  
> +static void arm_cpu_parse_features(CPUState *cs, char *features,
> +                                   Error **errp)
> +{
> +    ARMCPU *cpu = ARM_CPU(cs);
> +    char *featurestr;
> +
> +    featurestr = features ? strtok(features, ",") : NULL;
> +    while (featurestr) {
> +        if (featurestr[0] == '-') {
...
> +        } else if (featurestr[0] == '+') {
Please do not use legacy +-feature format and support only foo=val format.
Other targets have it only for to being able support legacy setups
which use +- format.

> +            /* Everything else is a bad format */
> +            error_setg(errp, "CPU property string '%s' not in format "
> +                             "(+feature|-feature|feature=xyz)", featurestr);


> +            return;
> +        }
> +        featurestr = strtok(NULL, ",");
> +    }
> +}
> +
>  static void arm_cpu_class_init(ObjectClass *oc, void *data)
>  {
>      ARMCPUClass *acc = ARM_CPU_CLASS(oc);
> @@ -1183,6 +1225,7 @@ static void arm_cpu_class_init(ObjectClass *oc, void *data)
>      cc->set_pc = arm_cpu_set_pc;
>      cc->gdb_read_register = arm_cpu_gdb_read_register;
>      cc->gdb_write_register = arm_cpu_gdb_write_register;
> +    cc->parse_features = arm_cpu_parse_features;
>  #ifdef CONFIG_USER_ONLY
>      cc->handle_mmu_fault = arm_cpu_handle_mmu_fault;
>  #else