qemu-arm
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-arm] [RFC PATCH 02/30] arm: introduce ARM_V8_FP16 feature bit


From: Richard Henderson
Subject: Re: [Qemu-arm] [RFC PATCH 02/30] arm: introduce ARM_V8_FP16 feature bit
Date: Fri, 13 Oct 2017 13:44:07 -0700
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0

On 10/13/2017 09:24 AM, Alex Bennée wrote:
> ---
>  target/arm/cpu.h   | 1 +
>  target/arm/cpu64.c | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/target/arm/cpu.h b/target/arm/cpu.h
> index 89d49cdcb2..3a0f27c782 100644
> --- a/target/arm/cpu.h
> +++ b/target/arm/cpu.h
> @@ -1340,6 +1340,7 @@ enum arm_features {
>      ARM_FEATURE_VBAR, /* has cp15 VBAR */
>      ARM_FEATURE_M_SECURITY, /* M profile Security Extension */
>      ARM_FEATURE_JAZELLE, /* has (trivial) Jazelle implementation */
> +    ARM_FEATURE_V8_FP16, /* implements v8.2 half-precision float */
>  };
>  
>  static inline int arm_feature(CPUARMState *env, int feature)
> diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
> index 670c07ab6e..973614dfc6 100644
> --- a/target/arm/cpu64.c
> +++ b/target/arm/cpu64.c
> @@ -226,6 +226,7 @@ static void aarch64_any_initfn(Object *obj)
>      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_FP16);
>      cpu->ctr = 0x80038003; /* 32 byte I and D cacheline size, VIPT icache */
>      cpu->dcz_blocksize = 7; /*  512 bytes */
>  }
> 

Need to update linux-user/elfload.c, get_elf_hwcap as well (HWCAP_ASIMDHP).
I suppose that will be a separate patch, since we're missing 8 bits from
current linux/arch/arm64/include/uapi/asm/hwcap.h.

... and we probably need to report a kernel arm32 bug that there is no
equivalent bit defined there.

Anyway, as far as this goes,
Reviewed-by: Richard Henderson <address@hidden>


r~



reply via email to

[Prev in Thread] Current Thread [Next in Thread]